Which of the following statement(s) is/are correct concerning cell junctions? a. The major occluding junction is the tight junction or zonula occludens b. Tight junctions are usually located near the basal pole of the cell c. Desmosomes are button-like points of attachment which serve to weld together adjacent cells d. Gap junctions are a type of cell junction specialized for cell communication

Which of the following statement(s) is/are correct concerning cell junctions? a. The major occluding junction is the tight junction or zonula occludens b. Tight junctions are usually located near the basal pole of the cell c. Desmosomes are button-like points of attachment which serve to weld together adjacent cells d. Gap junctions are a type of cell junction specialized for cell communication
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Answer: a, c, d  Cell junctions are classified as occluding, anchoring, and communicating. The major occluding junction is the tight junction or zonula occludens which connects cells in epithelia and thereby allows epithelia to serve as selective permeability barriers. Tight junctions are normally located near the apical pool of the cell and form a belt that completely encircles the cell. Anchoring junctions connect the cytoskeleton of the cell to the extracellular matrix or neighboring cells. Morphologically these are adherens junctions or desmosomes. Desmosomes are button-like points of attachment with a prominent intracellular plaque that serves to weld together adjacent cells by serving as anchoring sites for intermediate filaments within the cell. The third functional type of cell junction is a gap junction which is specialized for communication. This junction mediates both electrical and chemical coupling
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Which of the following statement(s) is/are true concerning water movement across cell membranes? a. Water moves only actively through cell membrane transport proteins b. For most cells of the body, the transmembrane hydrostatic pressure is 0 c. Water distribution is determined entirely by solute distribution d. Specialized cells such as the glomerulus of the kidney actively transport water to maintain hydrostatic pressure

Description : Which of the following statement(s) is/are true concerning water movement across cell membranes? a. Water moves only actively through cell membrane transport proteins b. For most cells of ... cells such as the glomerulus of the kidney actively transport water to maintain hydrostatic pressure

Last Answer : Answer: b, c The energetics of water transport across cell membranes is simplified by the fact that water moves only passively due to gradients of hydrostatic pressure or water ... water is distributed at equilibrium. Water distribution is determined entirely by solute to solute distribution

Which of the following statement(s) is/are true concerning the cell plasma membrane? a. The plasma membrane is composed of amphipathic molecules b. The hydrophobic core of the lipid bilayer of the cell membrane contains specialized transport proteins which maintain the intracellular ionic milieu different from the extracellular fluid c. Plasma membrane proteins extend externally and bear phospholipid moieties which contribute to the cell coat d. The membrane proteins of nerve cells are highly voltage-dependent

Description : Which of the following statement(s) is/are true concerning the cell plasma membrane? a. The plasma membrane is composed of amphipathic molecules b. The hydrophobic core of the lipid bilayer of the ... contribute to the cell coat d. The membrane proteins of nerve cells are highly voltage-dependent

Last Answer : Answer: a, b, d The plasma membrane defines the boundary of the cell and serves to contain and concentrate enzymes and other macromolecule constituents. The plasma membrane is ... and bear carbohydrate moieties primarily as oligosaccharide chains that contribute to the cell coat or glycocalyx

In contrast to a patient undergoing an elective operation, which of the following statement(s) is/are true concerning a patient who has suffered a multiple trauma? a. Basal metabolic rates are similar b. The patient is highly sensitive to insulin c. Utilization of the amino acids, glutamine and alanine, is similar to their composition in skeletal muscle d. Fat and protein stores are rapidly depleted

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Last Answer : Answer: b, d The degree of hypermetabolism is generally related to the severity of injury. Patients with long-bone fractures have a 15-25% increase in metabolic rate, whereas metabolic ... in injured subjects, if unfed, severely injured patients rapidly deplete their fat and protein stores

The neurohormonal arm of the stress response is well defined. Less is known about the inflammatory arm mediated primarily by cytokines. Which of the following statement(s) is/are true concerning this arm of the surgical stress response? a. Cytokines primarily work locally via direct cell-to-cell communication b. Cytokines are never detectable in the systemic bloodstream c. Cytokines are produced only by immune cells attracted to the site of injury d. Cytokine release may stimulate the release of other cytokines leading to an important cascade of events

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Last Answer : Answer: a, d Cytokines, which are produced at the site of injury by endothelial cells and by diverse immune cells throughout the body, also occupy a pivotal position in the stress response ... act as hormones and spill over into the systemic circulation and become detectable in the bloodstream

The following statement(s) is/are true concerning cellular defense mechanisms. a. Macrophages function solely as antigen processing cells in the initial reaction to exposure to an antigen b. Macrophages may become activated and secrete cytokines c. Macrophages serve as phagocytic cells in the tissues but not within the bloodstream d. Polymorphonucleocytes (PMNS) are normally present in only small numbers within the tissue and enter an area of infection through diapedesis

Description : The following statement(s) is/are true concerning cellular defense mechanisms. a. Macrophages function solely as antigen processing cells in the initial reaction to exposure to an antigen b. Macrophages ... in only small numbers within the tissue and enter an area of infection through diapedesis

Last Answer : Answer: b, d A wide variety of cell types serve to provide host defense at several levels. Macrophages act as the initial antigen processing cell that serves to ... through diapedesis after chemotactic stimuli are excluded by macrophages, bacterial breakdown products, and complement activation

Which of the following statement(s) is/are true concerning translation of the mRNA message to protein synthesis? a. An adaptor molecule, tRNA, recognizes specific nucleic acid bases and unites them with specific amino acids b. Covalent attachment of tRNA to amino acids is energy dependent c. The formation of a peptide bond between the growing peptide chain and the free amino acid occurs in the free cytoplasm d. Complete protein synthesis takes hours

Description : Which of the following statement(s) is/are true concerning translation of the mRNA message to protein synthesis? a. An adaptor molecule, tRNA, recognizes specific nucleic acid bases and unites them ... and the free amino acid occurs in the free cytoplasm d. Complete protein synthesis takes hours

Last Answer : Answer: a, b The synthesis of protein involves conversion from a four-letter nucleotide language to one of 20 chemically distinct amino acids. This process is referred to as ... translation and be moving down the mRNA molecules simultaneously, thus increasing the rate of protein synthesis

The complement system consists of a series of serum proteins that exist in a quiescent or very low-level state of activation in the uninfected host. Which of the following statement(s) is/are true concerning complement activation? a. The alternate (properdin) pathway of complement activation can occur directly through contact with fungal or bacterial cell wall compounds b. Complement component fragments may serve to decrease vascular permeability c. Excessive complement activation can produce deleterious effects d. Fragments of certain complement components serve as chemoattractants to additional cellular components of the host defense mechanism

Description : The complement system consists of a series of serum proteins that exist in a quiescent or very low-level state of activation in the uninfected host. Which of the following ... certain complement components serve as chemoattractants to additional cellular components of the host defense mechanism

Last Answer : Answer: a, c, d Complement activation can occur through either classic or alternate (properdin) pathways, both of which eventuate in deposition of terminal complement pathway components on the ... and release of lysosomal enzymes that can directly damage certain target tissues, such as the lung

Which of the following statements(s) is/are true concerning human energy requirement? a. In normal subjects, less than 5% of basal energy requirement is spent on cardiac output and the work of breathing b. Mechanical ventilation can decrease the energy expenditure for normal respiration c. For a 70 kg male, average resting energy consumption is almost 1500 kcal/day d. Similar increases in energy expenditures are associated with elective surgery and trauma or thermal injury

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Last Answer : Answer: a, c Basal energy requirements are measured with the subject at rest when no external work is being done; the energy is used mainly for transport and synthetic work within cells. A ... average-sized adult who sustains a major burn rarely may require more than 3500 kcal/day for maintenance

Infectious disease transmission during blood transfusions is of clinical significance to surgeons and of major importance to patients contemplating surgery potentially associated with the need for blood administration. Which of the following statement(s) is/are true concerning the transmission of infectious disease during blood transfusions? a. Post-transfusion hepatitis is usually due to hepatitis B b. Hepatitis and HIV transmission is greatest with the administration of pooled plasma products such as serum albumin c. The most important cause of post-transfusion disease in immunosuppressed patients is CMV infection d. The risk of HIV transmission in blood transfusions is significantly less than the risk of hepatitis transmission

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The initiation of a humoral immune response involves a complex interaction of the antigen, cells and intercellular messengers. Which of the following statement(s) concerning the initiation of the humoral immune response is/are correct? a. Helper T lymphocytes stimulate B lymphocytes through secretion of cytokines such as interleukin 4 and 6 b. A number of cells can aid in presenting the antigen to the helper T cell including B lymphocytes and macrophages c. All antigens require coordinated efforts of the various cellular components of the immune system d. An antigen must be a living microorganism

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Cell regulation can be thought of as the effector side of cell communication. Most commonly cell regulation occurs by means of extracellular chemical messengers. Which of the following statement(s) is/are true concerning these messengers? a. Paracrine regulation involves a messenger which is produced and acts systemically b. The extracellular signal or stimulus is received by a receptor on or in the target cell c. Neurocrine regulation depends on a physical connection between the neuron and the target cell d. Most hormones, local mediators, and neurotransmitters readily cross the cell plasma membrane

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Last Answer : Answer: b, c Depending on how the extracellular messenger arrives, cell regulation can be classified as paracrine, endocrine, or neurocrine. In paracrine regulation, a chemical messenger ... , local mediators, and neurotransmitters are water-soluble and cannot readily cross the plasma membrane

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Description : Interleukin-6 is recognized as the cytokine primarily responsible for the alteration in hepatic protein synthesis recognized as the acute phase response. Which of the following statement(s) is/are true ... physiologic role of acute phase proteins are to reduce the systemic effects of tissue damage

Last Answer : Answer: c, d IL-6 is now recognized at the cytokine primarily responsible for the alteration in hepatic synthesis recognized as the acute phase response. Glucocorticoid hormones augment ... that generally inhibit the tissue destruction that is associated with the local initiation of inflammation

Cytokines are low-molecular-weight polypeptides exerting a wide variety of biologic effects at both local and systemic levels. Which of the following statement(s) is/are true concerning the production and actions of cytokines? a. Cytokines are produced solely by macrophages b. Cytokines act only on other cells within the same local environment c. Cytokines may have both protective and deleterious effects on the host d. Each specific cytokine is produced by a single cell type

Description : Cytokines are low-molecular-weight polypeptides exerting a wide variety of biologic effects at both local and systemic levels. Which of the following statement(s) is/are true concerning the production and ... effects on the host d. Each specific cytokine is produced by a single cell type

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Which of the following statement(s) is/are true concerning the proliferative phase of wound healing? a. The macrophage is the predominant cell type b. The pink or purple-red appearance of a wound is due to ingrowth and proliferation of endothelial cells c. Collagen, the dominant structural molecule of the wound matrix, contains two unique amino acids, hydroxyproline and hydroxylysine d. The predominant collagen type in a scar is type 3

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Last Answer : Answer: b, c The proliferative phase of wound healing begins with the formation of a provisional matrix of fibrin and fibronectin as part of the initial clot formation. Initially, the provisional ... The principal collagen type scar is type 1, with lesser amounts of type 3 collagen also present

Which of the following statement(s) is/are correct concerning the management of an open wound? a. Frequent surgical debridement is usually necessary b. Water irrigation can effectively debride most wounds c. Hydrogen peroxide is particularly useful in the management of open wounds d. A number of the newer dressing products have clearly been shown to promote wound healing compared to simple moist occlusive dressing

Description : Which of the following statement(s) is/are correct concerning the management of an open wound? a. Frequent surgical debridement is usually necessary b. Water irrigation can effectively debride ... products have clearly been shown to promote wound healing compared to simple moist occlusive dressing

Last Answer : Answer: b Although there are numerous dressing products commercially available at present, no treatment has been demonstrated to improve healing beyond that of standard treatment which adheres to basic ... healing is achieved, there has been no evidence that one product is better than another

Which of the following statements concerning perioperative nutrition is true concerning the above-described patient? a. Since the patient’s weight had been stable with no preoperative nutritional deficit, 5% dextrose intravenous solutions are adequate for the initial postoperative source of nutrition b. Preoperative immunologic status should be determined including total peripheral lymphocyte count and delayed hypersensitivity reaction to determine skin-test response to common antigens c. Routine postoperative fluid administration with intravenous 5% glucose solutions can provide the calories to meet basal energy requirements d. A jejunal feeding catheter should be placed at the time of surgery for postoperative enteral feeding

Description : Which of the following statements concerning perioperative nutrition is true concerning the above-described patient? a. Since the patient's weight had been stable with no preoperative nutritional deficit ... feeding catheter should be placed at the time of surgery for postoperative enteral feeding

Last Answer : Answer: a Most patients undergoing elective operations are adequately nourished. Unless the patient has suffered significant preoperative malnutrition, characterized by weight loss greater than ... gastrointestinal surgery, this technique would not appear indicated in the patient described above

A striking feature of living cells is a marked difference between the composition of the cytosol and the extracellular milieu. Which of the following statement(s) concerning the mechanisms of maintenance of these differences is/are true? a. The cell membrane is able to maintain a 10,000 fold gradient between the extracellular concentration of ionized calcium and the intracellular concentration b. The key to these differences is the fact that the plasma membrane is normally impermeable to sodium, potassium and calcium c. The selectivity of biologic membranes is highly consistent and seldom changes d. The selectivity of cell membranes relates only to ions and not organic compounds

Description : A striking feature of living cells is a marked difference between the composition of the cytosol and the extracellular milieu. Which of the following statement(s) concerning the mechanisms of maintenance ... d. The selectivity of cell membranes relates only to ions and not organic compounds

Last Answer : Answer: a The survival of the cell requires that cytosolic composition be maintained within narrow limits, despite the constant influx of nutrients and the simultaneous outflow of waste. A ... be altered drastically as a result of regulatory or signaling processes that occur within the cell

Which of the following statement(s) is/are true concerning the cell function of phagocytosis? a. Phagocytosis is a mechanistically distinct process of endocytosis performed by special cells to take up larger particles such as bacteria or erythrocytes b. Lymphocytes are the primary blood cell involved with this process c. The process involves a coating of the cytoplasmic surface known as clathrin d. Phagocytosis is performed only by white blood cells and tissue macrophages

Description : Which of the following statement(s) is/are true concerning the cell function of phagocytosis? a. Phagocytosis is a mechanistically distinct process of endocytosis performed by special cells to take ... known as clathrin d. Phagocytosis is performed only by white blood cells and tissue macrophages

Last Answer : Answer: a Phagocytosis is a specialized form of endocytosis by which large particles are internalized by specialized cells primarily macrophages and neutrophils. To be phagocytosed, particles ... the lumen of the thyroid follicle, thereby releasing the thyroid hormones, thyroxine triiodothyronine

Most hormone receptors are localized on the cell membrane and transduce hormone binding into altered levels of intracellular messengers. A limited number of intracellular receptors do exist. Which of the following statement(s) is/are true concerning intracellular receptors? a. The messengers or hormones must by lipophilic b. These intracellular receptors generally regulate protein synthesis c. The intracellular receptors are located entirely in the nucleus of the cell d. A heat-shock protein serves as an inhibitor protein blocking the DNA-binding domain of the steroid receptor

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Last Answer : Answer: a, d Although most hormone and other messenger receptors are extracellular, intracellular receptors have been identified. The hormone messengers involved for these receptors are primarily ... DNA-binding domain of the receptor. Activation involves the dissociation of the inhibitor protein

Which of the following statement(s) is/are correct concerning the immunoinflammatory response to shock? a. The anaphylactoxins, C3a and C5a, are products of activation of only the classical pathway of the compliment cascade b. Eicosanoids, such as prostaglandins are stored in platelets and endothelial cells and released in response to inflammatory stimuli c. Thromboxane and PGI2 have similar effects d. Platelet-activating factor can be released by both circulating and fixed tissue cells

Description : Which of the following statement(s) is/are correct concerning the immunoinflammatory response to shock? a. The anaphylactoxins, C3a and C5a, are products of activation of only the classical pathway ... effects d. Platelet-activating factor can be released by both circulating and fixed tissue cells

Last Answer : Answer: d Inflammatory mediators have recently been recognized as playing a significant role in the clinical manifestations and progression of shock and the development ... increased pulmonary vascular resistance, bronchoconstriction, peripheral vasodilatation, and increased vascular permeability

Which of the following statement(s) is/are true concerning the various types of shock? a. Traumatic shock is more commonly associated with subsequent organ injury and multiorgan failure syndrome than hemorrhagic shock b. Cardiogenic shock can be of either an intrinsic or compressive nature c. Hypodynamic septic shock is associated with a decreased mortality risk when compared with hyperdynamic septic shock d. Hypoadrenal shock usually responds quickly to resuscitation e. Neurogenic shock occurs with the absence of sympathetic activity

Description : Which of the following statement(s) is/are true concerning the various types of shock? a. Traumatic shock is more commonly associated with subsequent organ injury and multiorgan failure ... responds quickly to resuscitation e. Neurogenic shock occurs with the absence of sympathetic activity

Last Answer : Answer: a, b, d, e Classification schemes of shock based on cause have been developed for the seemingly dissimilar processes leading to circulatory collapse and the shock state. ... and pressor agents. The response to exogenous corticosteroids is usually dramatic and potentially life-saving

The following statement(s) is/are true concerning necrotizing fascitis. a. Mortality rates as high as 40% can be expected b. The infection involves only the superficial fascia, sparing the deep muscular fascia c. An impaired immune system is a common factor predisposing to this condition d. The infection is usually polymicrobial e. Necrotizing fascitis is most likely to develop in the face of impaired fascial blood supply

Description : The following statement(s) is/are true concerning necrotizing fascitis. a. Mortality rates as high as 40% can be expected b. The infection involves only the superficial fascia, sparing the deep ... e. Necrotizing fascitis is most likely to develop in the face of impaired fascial blood supply

Last Answer : Answer: a, c, d, e Necrotizing fascitis is an uncommon infection of the deep and superficial fascia that is associated with mortality as high as 40% in many series. ... fulminant and is frequently associated with cellulitis, myositis, fascitis, and bacteremia with attendant high mortality

Thrombolytic therapy has become a useful adjunct in the management of peripheral arterial occlusion. In this setting, direct intraarterial administration rather than intravenous has been advocated to decrease the risk of systemic bleeding. Which of the following true statement(s) concerning the use of thrombolytic agents for arterial occlusion is/are true? a. A standard technique involves infusing high-dose urokinase, 4000 units per minute for 1–2 hours, directly into the clot by a catheter embedded in the thrombus b. If progress is made, further fibrinolytic therapy is given at 1000 to 2000 units per minute until clot lysis has occurred c. The usual infusion time by the above-stated technique is usually in excess of 24 hours d. Successful clot lysis occurs more frequently in arterial graf

Description : Thrombolytic therapy has become a useful adjunct in the management of peripheral arterial occlusion. In this setting, direct intraarterial administration rather than intravenous has been advocated ... may be indicated for situations where complete clot evacuation cannot be accomplished surgically

Last Answer : Answer: a, b, e The most popular method for intraarterial thrombolytic therapy for arterial occlusion involves passing a guidewire through the thrombus with arteriographic guidance and ... acute arterial occlusion) or when distal vasculative is occluded and precludes appropriate inflow patency

Antithrombin III deficiency is a commonly observed hypercoaguable state. Which of the following statement(s) is/are true concerning this condition? a. A patient with this deficiency usually presents with thrombosis while on heparin or exhibits an inability to become adequately anticoagulated with heparin b. This deficiency may be either congenital or acquired c. Thrombotic episodes are related to predisposing events such as operations, childbirth, and infections d. Treatment involves acutely the administration of fresh frozen plasma followed by long-term treatment with Coumadin

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Last Answer : Answer: a, b, c, d Antithrombin III deficiency accounts for about 2% of venous thrombotic event. This deficiency has been described in patients with pulmonary embolism, mesenteric venous ... is established, fresh frozen plasma should be administered followed by long-term treatment with Coumadin

Which of the following statement(s) is/are true concerning the pulmonary response to shock? a. The acute pulmonary vascular response to shock differs markedly from that of systemic vasculature b. The pulmonary edema of ARDS occurs in the face of elevated left heart pressures c. The initial physiologic changes of ARDS involve the capillary endothelial cells and the type I pneumocyte d. Mechanisms proposed in the pathogenesis of ARDS include injury from mediators of inflammation elsewhere and from activated cellular elements e. A decrease in lung compliance may result from the loss of type I pneumocytes

Description : Which of the following statement(s) is/are true concerning the pulmonary response to shock? a. The acute pulmonary vascular response to shock differs markedly from that of systemic vasculature b. The ... elements e. A decrease in lung compliance may result from the loss of type I pneumocytes

Last Answer : Answer: c, d, e Contributing pathophysiologic processes to the pulmonary manifestations of shock include the pulmonary component of the cardiovascular response, disruption of the normal ... injury from mediators of inflammation elaborated elsewhere, and from activated cellular blood elements

Cell junctions called tight , adhering and gap junctions are found in

Description : Cell junctions called tight , adhering and gap junctions are found in

Last Answer : Cell junctions called tight , adhering and gap junctions are found in A. Neural tissue B. Muscular tissue C. Connective tissue D. Epithelium tissue

The cell junctions called tight, adhering and gap junctions are found in (a) connective tissue (b) epithelial tissue (c) neural tissue (d) muscular tissue

Description : The cell junctions called tight, adhering and gap junctions are found in (a) connective tissue (b) epithelial tissue (c) neural tissue (d) muscular tissue

Last Answer : (b) epithelial tissue

Transfusions of blood products can be associated with a number of complications including immediate and delayed hemolytic reactions; nonhemolytic reactions; infectious disease transmission; and complications of massive transfusions. Which of the following statements are true concerning complications of blood transfusions? a. Immediate hemolytic transfusion reactions are caused by major ABO blood group incompatibility b. Nonhemolytic transfusion reactions are usually due to RH incompatibility and are therefore more common in women of childbearing age c. The most common complication of massive blood transfusion is dilutional thrombocytopenia d. Routine impaired calcium supplementation is necessary during most massive transfusion episodes

Description : Transfusions of blood products can be associated with a number of complications including immediate and delayed hemolytic reactions; nonhemolytic reactions; infectious disease transmission; and ... d. Routine impaired calcium supplementation is necessary during most massive transfusion episodes

Last Answer : Answer: a, c Immediate hemolytic reactions are usually caused by blood group ABO incompatibility although they may be caused by antigens of other blood group systems ... when associated with massive transfusion during complex intraoperative procedures such as thoracoabdominal aneurysm resection

Which of the following statement(s) is/are true concerning tumor necrosis factor (TNF)? a. TNF is a product of activated macrophages secreted in response to contact with endotoxin or lipopolysaccharide, antibody complexes, or inflammatory stimuli b. The liver and gut appear to be a major source of TNF following hypoperfusion c. Circulating levels of TNF correlate well with severity of tissue injury in shock d. Recently completed clinical trials of anti-TNF antibody in septic patients shows a marked improvement in survival

Description : Which of the following statement(s) is/are true concerning tumor necrosis factor (TNF)? a. TNF is a product of activated macrophages secreted in response to contact with endotoxin or ... completed clinical trials of anti-TNF antibody in septic patients shows a marked improvement in survival

Last Answer : Answer: a, b Tumor necrosis factor (TNF), a protein product of activated macrophages, is secreted in response to contact with endotoxin or lipopolysaccharide, antibody complexes, or ... patients utilizing infusion of monoclonal antibodies to the TNF molecule have shown no overall survival benefit

Bleeding complications are frequently associated with fibrinolytic therapy. Which of the following statement(s) concerning complications of fibrinolytic therapy is/are true? a. Careful monitoring of prothrombin time and aPTT time are necessary to avoid bleeding complications b. A level of serum fibrinogen less than 100 mg/dl is associated with an increased risk of bleeding c. Recent (less than 10 days) major surgery is a contraindication to systemic but not regional fibrinolytic therapy d. A patient with a cerebrovascular event occurring less than two months ago can be treated with fibrinolytic therapy if head CT scan is normal

Description : Bleeding complications are frequently associated with fibrinolytic therapy. Which of the following statement(s) concerning complications of fibrinolytic therapy is/are true? a. Careful monitoring of prothrombin time ... months ago can be treated with fibrinolytic therapy if head CT scan is normal

Last Answer : Answer: b Fibrinolytic therapy induces a hemostatic defect through a combination of factors. Hypofibrinogenemia and fibrin degradation products inhibit fibrin polymerization and, in combination ... is considered a major relative contraindication to either regional or systemic thrombolytic therapy

A 59-year-old trauma patient has suffered multiple septic complications including severe pneumonia, intraabdominal abscess, and major wound infection. He has now developed signs of multisystem organ failure. Which of the following statement(s) is/are true concerning necessary changes to be made in his nutritional management? a. Carbohydrate load should be reduced in the face of respiratory failure b. In patients with renal failure, protein intake should be diminished c. During hemodialysis protein intake should be limited to the same extent d. In patients with hepatic failure, carbohydrate load should be increased

Description : A 59-year-old trauma patient has suffered multiple septic complications including severe pneumonia, intraabdominal abscess, and major wound infection. He has now developed signs of multisystem organ ... the same extent d. In patients with hepatic failure, carbohydrate load should be increased

Last Answer : Answer: a, b The most severe complication of sepsis is multiple system organ dysfunction syndrome, which may result in death. The development of organ failure requires changes in the ... should be provided as fat emulsion. If encephalopathy develops, protein load should also be reduced0

Which of the following statement(s) concerning intravenous nutritional support is/are true? a. Concentrations of glucose no higher than 5% should be used to avoid peripheral vein sclerosis b. A major disadvantage of the peripheral technique is limited caloric delivery c. If total parenteral nutrition is required, access to the superior vena cava via the external jugular vein is the most suitable site d. Venous thrombosis is an uncommon complication for long-term central vein catheterization

Description : Which of the following statement(s) concerning intravenous nutritional support is/are true? a. Concentrations of glucose no higher than 5% should be used to avoid peripheral vein sclerosis ... suitable site d. Venous thrombosis is an uncommon complication for long-term central vein catheterization

Last Answer : Answer: b Although peripheral access can be used for intravenous nutrition, the major disadvantage of this technique is limited caloric delivery to meet catabolic demands within tolerated fluid ... studies that use phlebography or radionucleotide venography indicate the incidence is as high as 35%

Which of the following statement(s) is/are true concerning protein/amino acid metabolism in man? a. The major source of amino acids is breakdown of circulating proteins b. The recommended daily allowance for protein may triple in critically ill patients c. Urinary nitrogen losses will approach 0 in the face of protein starvation d. Negative nitrogen balance refers to a decrease in nitrogen taken into the body versus the amount of nitrogen lost

Description : Which of the following statement(s) is/are true concerning protein/amino acid metabolism in man? a. The major source of amino acids is breakdown of circulating proteins b. The recommended daily ... balance refers to a decrease in nitrogen taken into the body versus the amount of nitrogen lost

Last Answer : Answer: b, d About 15% of the total body weight is made up of proteins, about half of which are intracellular and half extracellular. In man and other animals, dietary protein is the source of ... is exceeded by the amount of nitrogen lost in the urine, stool, skin, wounds, and fistula drainage

Fatty acids are a major energy source for the body. Which of the following statement(s) is/are true concerning the use of fatty acids as an energy source? a. Fatty acids are stored in adipocytes as triglycerides b. Hormone-sensitive lipase is present only in adipose tissue c. Fatty acids are released into the circulation traveling freely in plasma d. Approximately 25% of total nonprotein caloric needs supplied via total parenteral nutrition should be in the form of fat

Description : Fatty acids are a major energy source for the body. Which of the following statement(s) is/are true concerning the use of fatty acids as an energy source? a. Fatty acids are stored in ... 25% of total nonprotein caloric needs supplied via total parenteral nutrition should be in the form of fat

Last Answer : Answer: a, b, d In most tissues, fatty acids are readily oxidized for energy. They are especially important energy sources for the heart, liver and skeletal muscle. In ... administered to patients receiving total parenteral nutrition should comprise about 5-30% of total nonprotein caloric needs

Although TPN has major beneficial effects to the patient and specific organ systems, TPN has a downside which is related to intestinal disuse. Which of the following statement(s) is/are true concerning the effects of TPN on the GI tract? a. Patients receiving TPN have an accentuated systemic response to endotoxin challenge compared to enterally fed volunteers b. TPN can result in disruption of intestinal microflora c. In experimental models, bacterial translocation from the gut is increased d. Effects of TPN on the gut may lead to multiple organ failure

Description : Although TPN has major beneficial effects to the patient and specific organ systems, TPN has a downside which is related to intestinal disuse. Which of the following statement(s) is/are true concerning the ... from the gut is increased d. Effects of TPN on the gut may lead to multiple organ failure

Last Answer : Answer: a, b, c, d A number of studies have examined the effects of TPN on intestinal function and immunity. Although most of these studies have been done in animal models, ... the release of bacteria and/or cytokines leading to pronounced systemic responses and possibly multiple organ failure

A 17-year-old patient involved in an automobile accident is paralyzed with multiple peripheral extremity injuries. Nutritional support is instituted with a transnasal feeding catheter. Which of the following statement(s) is/are true concerning the patient’s management? a. Feeding into the stomach results in stimulation of the biliary/pancreatic axis which is probably trophic for small bowel b. Gastric secretions will dilute the feedings increasing the risk of diarrhea c. The major risk in this patient is tracheobronchial aspiration d. Placement of the feeding catheter through the pylorus into the first portion of the duodenum reduces the risk of regurgitation and aspiration

Description : A 17-year-old patient involved in an automobile accident is paralyzed with multiple peripheral extremity injuries. Nutritional support is instituted with a transnasal feeding catheter. Which of the ... pylorus into the first portion of the duodenum reduces the risk of regurgitation and aspiration

Last Answer : Answer: a, c, d The use of transnasal feeding catheters for intragastric feeding or for duodenal intubation are popular adjuncts for providing nutritional support by the enteral route. The ... the fourth portion of the duodenum reduces the risk of regurgitation and aspiration of feeding formulas

Which of the following statement(s) is/are true concerning ischemia reperfusion injury? a. During ischemia, ATP degradation results in increased plasma and intracellular levels of hypoxanthine and xanthene b. Oxygen free radicals such as the superoxide radical are involved in the expression of the proinflammatory phenotype of endothelial cells, macrophages and neutrophils c. The intracellular adhesion molecule-1 (ICAN-1) contributes to injury and disruption of the endothelial lining, with extensive capillary leak and resultant interstitial edema d. Animal models have demonstrated that passive immunization with antibodies to neutrophil adhesive complex lessen the ischemic/reperfusion microvascular injury

Description : Which of the following statement(s) is/are true concerning ischemia reperfusion injury? a. During ischemia, ATP degradation results in increased plasma and intracellular levels of ... immunization with antibodies to neutrophil adhesive complex lessen the ischemic/reperfusion microvascular injury

Last Answer : Answer: a, b, c, d During the ischemia and hypoperfusion phase, degradation of ATP stores essential to maintain cell integrity and significant loss of diffusible ... either the neutrophil adhesive complex or the endothelial selectins dramatically lessens ischemia/reperfusion microvascular injury

The following statement(s) is/are true concerning host defense mechanisms to intraabdominal infection. a. Bacterial clearance can occur via translymphatic absorption b. Phagocytic activity and bacterial killing can occur via resident phagocytic cells and an influx of PMNs c. A fibrinogen-rich inflammatory exudate is released into the peritoneal cavity, trapping large numbers of bacteria and other particulate matter d. Perforations of a bowel may be walled off but are seldom sealed by the omentum and other mobile viscera

Description : The following statement(s) is/are true concerning host defense mechanisms to intraabdominal infection. a. Bacterial clearance can occur via translymphatic absorption b. Phagocytic activity and bacterial killing can ... may be walled off but are seldom sealed by the omentum and other mobile viscera

Last Answer : Answer: a, b, c The introduction of microorganisms into the normally sterile peritoneal environment invoke several potent specialized host antimicrobial defense mechanisms. Bacterial clearance, ... the contaminated enteric contents walled off, preventing continued soilage of the peritoneal cavity

The following statement(s) is/are true concerning HIV infection. a. Initial screening with ELISA is highly sensitive but can be associated with a false positive rate of 25% b. Treatment with azidothymidine (AZD) appears to prolong survival when administered early in the disease c. Predisposition to infection in HIV infection is primarily due to reduction in the number of helper T cells d. Common infections in patients with AIDS are Pneumocystis, carinii pneumonia, CMV pneumonitis, Cryptococcus meningitis, and disseminated infection due to atypical mycobacteria

Description : The following statement(s) is/are true concerning HIV infection. a. Initial screening with ELISA is highly sensitive but can be associated with a false positive rate of 25% b. ... , carinii pneumonia, CMV pneumonitis, Cryptococcus meningitis, and disseminated infection due to atypical mycobacteria

Last Answer : Answer: b, c, d Acquired immunodeficiency syndrome (AIDS) is a syndrome caused by the human retrovirus (HIV-1) that infects T lymphocytes and causes severe immunosuppression. Individuals who ... to prolong survival when administered early in the course of disease and is considered routine therapy

Reconstitution of the epithelial barrier (epithelialization) begins within hours of the initial injury. Which of the following statement(s) is/are true concerning the process of epithelialization? a. Bacteria, protein exudate, and necrotic tissue all will compromise this process b. Epithelial cells exhibit contact proliferation c. Epithelialization occurs only from the margins of the wound d. Visible scarring can occur only when the injury extends deeper than the superficial dermis

Description : Reconstitution of the epithelial barrier (epithelialization) begins within hours of the initial injury. Which of the following statement(s) is/are true concerning the process of epithelialization? a. ... d. Visible scarring can occur only when the injury extends deeper than the superficial dermis

Last Answer : Answer: a, d The initial step of epithelialization involves epithelial cells from the basal layer of the wound edge flattening and migrating across the wound, completing wound coverage within 24- ... abrasions and burns may scar significantly. Whenever the dermis is incised, a scar will form

Which of the following statement(s) is/are true concerning the role of glutamine in total parenteral nutrition? a. Glutamine is an essential amino acid b. Glutamine appears to be of primary benefit in critical illness c. Glutamine is included in most standard TPN solutions d. Glutamine is the primary energy source for intestinal mucosal cells of the small bowel and colon

Description : Which of the following statement(s) is/are true concerning the role of glutamine in total parenteral nutrition? a. Glutamine is an essential amino acid b. Glutamine appears to be of primary ... . Glutamine is the primary energy source for intestinal mucosal cells of the small bowel and colon

Last Answer : Answer: b Glutamine is the most studied gut-specific nutrient. Glutamine has been classified as a nonessential or nutritionally dispensable amino acid since glutamine can be synthesized in adequate ... . In contrast to glutamine, short chain fatty acids are primary energy source for colonocytes

Which of the following statement(s) is/are true concerning the multiorgan failure syndrome (MOFS)? a. Changes in the splanchnic and pulmonary microcirculation are critical to the development of MOFS b. Tissue fixed microphages, including the liver Kupffer cell, have little role in the development of MOFS c. MOFS represents systemic consequences of loss of homeostatic control of local inflammation and microcirculatory hypoperfusion d. The nature of MOFS is highly dependent upon the etiology of the underlying problem

Description : Which of the following statement(s) is/are true concerning the multiorgan failure syndrome (MOFS)? a. Changes in the splanchnic and pulmonary microcirculation are critical to the development of MOFS ... d. The nature of MOFS is highly dependent upon the etiology of the underlying problem

Last Answer : Answer: a, c The nature of multiorgan failure syndrome (MOFS) is that of a diffuse cellular injury, developing systemically as a consequence of losing homeostatic control of local ... of microorganism. In noninfectious cases, the response also appears independent of the specific underlying cause

Increasing evidence has implicated gram-negative bacterial lipopolysaccharide (LPS endotoxin) as the portion of the gram-negative bacterial cell membrane responsible for many, if not all the toxic effects that occur during gram-negative bacterial sepsis. The following statement(s) is/are true concerning LPS and the host response. a. The LPS molecule can in itself cause physiologic responses similar to that seen during gram-negative bacterial sepsis b. LPS triggers host macrophages to release a variety of cytokines including TNF-a, IL-1a, and IL-1b, IL-6, and IFN-a c. Excessive cytokine production is not associated with detrimental consequences d. TNFa and IL-1b appear to be the primary mediators within the host, exerting deleterious effects on the host when excessive amounts reach the syst

Description : Increasing evidence has implicated gram-negative bacterial lipopolysaccharide (LPS endotoxin) as the portion of the gram-negative bacterial cell membrane responsible for many, if not all the ... host, exerting deleterious effects on the host when excessive amounts reach the systemic circulation

Last Answer : Answer: a, b, d The LPS molecule exerts diverse effects on the mammalian host. Immunologic responses to LPS include nonspecific polyclonal B-cell proliferation, macrophage activation and ... deleterious effects on the host only after large amounts are secreted and reach the systemic circulation

There are two properties of the cell necessary to maintain nonequilibrium cellular composition; the first is selectivity and the second is energy conversion. Which of the following statement(s) is/are true concerning energy converting transport? a. The site of energy conversion and transport in the plasma membrane involves the phospholipid component b. The Na+-K++-ATPase derives energy from hydrolysis of extracellular ATP c. In some systems, energy inherent in the transmembrane ion gradient can be used to drive transport of a second species d. Examples of species transported via secondary active transport include hydrogen ions, calcium, amino acids and glucose

Description : There are two properties of the cell necessary to maintain nonequilibrium cellular composition; the first is selectivity and the second is energy conversion. Which of the following statement(s ... transported via secondary active transport include hydrogen ions, calcium, amino acids and glucose

Last Answer : Answer: c, d The selectivity of the plasma membrane, although impressive, cannot account for the nonequilibrium composition of living cells. A cell can be maintained in a nonequilibrium state only by ... to drive the transport of a second species such as protons, calcium, amino acids, or glucose

Which of the following statement(s) is/are true concerning cell membrane receptors? a. The largest family of cell surface receptors are the G-protein-linked receptors b. Activities of the G-protein involve binding and hydrolysis of ATP c. The G protein receptor generates an intracellular messenger commonly through the use adenylate cyclase d. Tyrosine kinase receptors are considered G-protein-linked receptors

Description : Which of the following statement(s) is/are true concerning cell membrane receptors? a. The largest family of cell surface receptors are the G-protein-linked receptors b. Activities of the ... through the use adenylate cyclase d. Tyrosine kinase receptors are considered G-protein-linked receptors

Last Answer : Answer: a, c All water-soluble regulatory molecules bind to the cell surface receptor proteins. Binding of the appropriate ligand evokes an intracellular signal which usually regulates ... are adenylate cyclase, which converts ATP to cAMP, and the polyphosphoinositide-specific phospholipase C

Which of the following statement(s) is/are true concerning DNA? a. DNA is contained only in the nucleus of the cell b. DNA strands are encoded by the sequence of four bases—adenine, guanine, cytosine and uridine c. The basic unit of information of DNA is the intron, a sequence of three bases d. There are an infinite number of possible codons

Description : Which of the following statement(s) is/are true concerning DNA? a. DNA is contained only in the nucleus of the cell b. DNA strands are encoded by the sequence of four bases-adenine, guanine, cytosine ... DNA is the intron, a sequence of three bases d. There are an infinite number of possible codons

Last Answer : Answer: a The genetic blueprint of an organism is carried in the nucleus of every cell, encoded by the sequence of four bases-adenine, guanine, cytosine and thymine, which together make up ... codons. Sixty-one of these code for amino acids and three are termination signals called stop codons

The transport of proteins out of the cell is termed exocytosis. Which of the following statement(s) is/are true concerning this process? a. Secretory vesicles fuse with the plasma membrane b. The process can occur in either a constitutive or regulated process c. A regulated secretion is triggered by a stimulus, most likely a hormone or a neurotransmitter d. A decrease in cytoplasmic calcium occurs as part of the secretion process

Description : The transport of proteins out of the cell is termed exocytosis. Which of the following statement(s) is/are true concerning this process? a. Secretory vesicles fuse with the plasma membrane b. ... or a neurotransmitter d. A decrease in cytoplasmic calcium occurs as part of the secretion process

Last Answer : Answer: a, b, c Transport vesicles that bud off the Golgi network carry both material to be secreted from the cell and protein destined to become components of the plasma ... but may also involve generation of diacylglycerol or production of cyclic AMP which activate kinases or phosphatases

Which of the following statement(s) is/are correct concerning the cardiovascular response to shock? a. Changes in cardiac contractile function shift the Frank Starling curve up and down b. Venoconstriction from skeletal muscle is a significant contributor to the restoration of blood volume with shock c. Arterial vasoconstriction affects all vascular beds equally d. The total circulating blood volume is equally split between the arterial and venous system

Description : Which of the following statement(s) is/are correct concerning the cardiovascular response to shock? a. Changes in cardiac contractile function shift the Frank Starling curve up and down b. ... d. The total circulating blood volume is equally split between the arterial and venous system

Last Answer : Answer: a Central in the general cardiovascular response to shock is the action of the heart itself. The principle determinants of cardiac function in the normal heart are the volume of blood ... Blood flow to the skin is sacrificed early, followed by that to the kidneys and splanchnic viscera

A 68-year-old male who underwent a repair of an abdominal aortic aneurysm 5 days ago, develops tachycardia, tachypnea, hypotension with cool, pale, mottled cyanotic extremities. He is agitated and complains of shortness of breath. Which of the following statement(s) is/ are correct concerning his diagnosis and management? a. Myocardial ischemia secondary to preexisting coronary artery disease is most likely the underlying cause of this problem b. Invasive hemodynamic monitoring with a Swan-Gantz catheter will demonstrate a low cardiac output, a high systemic vascular resistance, and elevated cardiac filling pressures c. The use of morphine sulphate and nitrates should be part of the initial management d. The primary pharmacologic treatment involves the use of moderate doses of inotropic ag

Description : A 68-year-old male who underwent a repair of an abdominal aortic aneurysm 5 days ago, develops tachycardia, tachypnea, hypotension with cool, pale, mottled cyanotic extremities. He ... use of moderate doses of inotropic agents e. Afterload reduction with nitroprusside is absolutely contraindicated

Last Answer : Answer: a, b, d Intrinsic cardiogenic shock results from failure of the heart as an effective pump. Coronary artery disease is the most common cause of myocardial ... hemodynamic monitoring. Infusion of afterload-reducing agents can be administered in conjunction with inotropic support