Hemostasis and the cessation of bleeding require which of the following processes? A. Adherence of platelets to exposed subendothelial glycoproteins and collagen with subsequent aggregation of platelets and formation of a hemostatic plug. B. Interaction of tissue factor with factor VII circulating in the plasma. C. The production of thrombin via the coagulation cascade with conversion of fibrinogen to fibrin. D. Cross-linking of fibrin by factor XIII.

Hemostasis and the cessation of bleeding require which of the following processes? A.  Adherence of platelets to exposed subendothelial glycoproteins and collagen with subsequent aggregation of platelets and formation of a hemostatic plug. B.  Interaction of tissue factor with factor VII circulating in the plasma. C.  The production of thrombin via the coagulation cascade with conversion of fibrinogen to fibrin. D.  Cross-linking of fibrin by factor XIII.
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Answer: ABCD  DISCUSSION: Hemostasis requires the interaction of platelets with the exposed subendothelial structures at the site of injury followed by aggregation of more platelets in that area. Interactions between endothelial cell and subendothelial tissue factor with factor VII activate the coagulation cascade. The end product is large amounts of thrombin that catalyze the conversion of fibrinogen into fibrin. Fibrin thus formed is cross-linked by factor XIII to form a stable clot that incorporates the platelet plug and fibrin thrombus into a stable clot
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In contrast to adult wound healing with scar formation, which of the following are characteristic of scarless fetal skin repair? A. Matrix rich in hyaluronic acid. B. Increased inflammatory response. C. Increased production of TGF-b. D. No collagen deposition. E. Minimal angiogenesis.

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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

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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

Which of the following statements regarding transforming growth factor b (TGF-b) are true? a. TGF-b expression is autoregulated b. TGF-b enhances collagen synthesis c. TGF-b inhibits extracellular matrix production d. TGF-b may inhibit or promote cellular proliferation

Description : Which of the following statements regarding transforming growth factor b (TGF-b) are true? a. TGF-b expression is autoregulated b. TGF-b enhances collagen synthesis c. TGF-b inhibits extracellular matrix production d. TGF-b may inhibit or promote cellular proliferation

Last Answer : Answer: a, b, d TGF-b appears to be one of the key cytokines in control of tissue repair. TGF-b is strongly chemotactic for neutrophils, T cells, monocytes, and fibroblasts. ... TGF-b stimulates the proliferation of densely plated human marrow fibroblasts, but is inhibitory at high concentrations

he primary mechanism by which heparin prevents coagulation of blood is: A. Direct inhibition of prothrombin to thrombin conversion B. Facilitation of antithrombin III mediated inhibition of factor Xa and thrombin C. Activation of antithrombin III to inhibit factors IX and XI D. Inhibition of factors XIIa and XIIIa

Description : he primary mechanism by which heparin prevents coagulation of blood is: A. Direct inhibition of prothrombin to thrombin conversion B. Facilitation of antithrombin III mediated inhibition of factor Xa and ... of antithrombin III to inhibit factors IX and XI D. Inhibition of factors XIIa and XIIIa

Last Answer : B. Facilitation of antithrombin III mediated inhibition of factor Xa and thrombi

Which of the following tissues contain significant collagen useful for placing sutures to allow the prolonged tension necessary to maintain tissue approximation? a. Dermis b. Intestinal submucosa c. Muscular fascia d. Blood vessel wall

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Description : Which of the following is/are true? A. Because of its thickness, the tensile strength of a healing wound on the eyelid is much less than one on the thick skin of the back. B. By 2 days, ... strength reaches a plateau by 3 weeks. D. Wounds rarely, if ever, regain the strength of intact tissues.

Last Answer : Answer: BD DISCUSSION: Tensile strength measures load per cross-section area at rupture, whereas burst strength measures load required to break a wound, regardless of dimension. Therefore, skin wounds have ... a slower rate for more than a year. Wounds do not regain the strength of normal tissue

Which of the following statements about septic shock are true? A. A circulating myocardial depressant factor may account for the cardiac dysfunction sometimes seen with shock due to sepsis or SIRS. B. A cardiac index (CI) of 6 liters per minute per square meter of body surface, a pulmonary capillary wedge pressure of 15 mm. Hg, and a systemic vascular resistance index (SVRI) of 800 dynes-sec/(cm 5-m 2) is a hemodynamic profile consistent with septic shock. C. An increase in SvO 2 in septic patients may be explained by the finding of anatomic arteriovenous shunts. D. Results of human trials employing antimediator therapy, such as antiendotoxin antibodies, IL-1 receptor antagonist, and tumor necrosis factor (TNF) antibodies, have confirmed animal studies that demonstrate a significant im

Description : Which of the following statements about septic shock are true? A. A circulating myocardial depressant factor may account for the cardiac dysfunction sometimes seen with shock due to sepsis or ... animal studies that demonstrate a significant improvement in survival with the use of such agents.

Last Answer : Answer: AB DISCUSSION: Shock due to sepsis or SIRS frequently manifests as a hyperdynamic cardiovascular response, consisting of an elevated CI and a decreased SVR or SVRI. Occasionally, ... been encouraging thus far in human clinical trials, despite the promising results from many animal studies

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

Description : 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 ... various cellular components of the immune system d. An antigen must be a living microorganism

Last Answer : Answer: a, b Stimulation of the immune system occurs after a variety of antigen-presenting cells (B lymphocytes, macrophages, dendritic cells, and Langerhans cells) act to engulf ... polysaccharides), most antigens require coordinated efforts of the various cellular components of the immune system

Von Willebrand’s disease is a common, congenital bleeding disorder. Which of the following statement(s) is/are true concerning Von Willebrand’s disease? a. As in hemophilia, it is much more common in men b. A history of spontaneous bleeding is common c. Screening laboratory tests will include a prolonged aPTT with a normal prothrombin time d. Pre-treatment for elective surgery require administration of cryoprecipitate to achieve levels of 23–50% of normal

Description : Von Willebrand's disease is a common, congenital bleeding disorder. Which of the following statement(s) is/are true concerning Von Willebrand's disease? a. As in hemophilia, it is ... -treatment for elective surgery require administration of cryoprecipitate to achieve levels of 23-50% of normal

Last Answer : Answer: c, d Von Willebrand's factor is an adhesive protein that mediates platelet adhesion to collagen. In addition, it protects and prevents the rapid removal of factor VIII ... platelet aggregation responses to ristocetin. The most reliable source of Von Willebrand's factor is cryoprecipitate

A patient with gross fecal contamination and peritonitis from a ruptured sigmoid diverticulum has his midline wound left open to heal by secondary intention. Which of the following statement(s) describes this healing process? a. Wounds healing in this fashion have an altered sequence of healing compared to a primarily closed wound b. A bed of granulation tissue forms over exposed subcutaneous tissue c. Epithelialization is enhanced in the face of bacterial colonization d. The ability of a wound to form granulation tissue is dependent on the blood supply of the tissue

Description : A patient with gross fecal contamination and peritonitis from a ruptured sigmoid diverticulum has his midline wound left open to heal by secondary intention. Which of the following statement(s) describes this ... of a wound to form granulation tissue is dependent on the blood supply of the tissue

Last Answer : Answer: b, d Open wounds, whether they be ulcers or open surgical incisions closing by secondary intention, heal with the same sequence of inflammation, matrix deposition, epithelialization ... via bacterial and phagocytic cell products such as proteases, collagenases, elastases, and other enzymes

Which of the following statements regarding fibroblasts and their function in wound healing are true? a. IL-1 has both inhibitory and promotional effects on fibroblast growth b. TNFa stimulates fibroblast collagen synthesis c. IL-1 and TNFa have opposite effects on the healing of bone d. In human clinical trials, EGF (epithelial growth factor) has been demonstrated to accelerate epidermal regeneration in cutaneous wounds

Description : Which of the following statements regarding fibroblasts and their function in wound healing are true? a. IL-1 has both inhibitory and promotional effects on fibroblast growth b. TNFa ... EGF (epithelial growth factor) has been demonstrated to accelerate epidermal regeneration in cutaneous wounds

Last Answer : Answer: a, d IL-1 appears to be important in the process of normal wound repair. IL-1 has been shown to stimulate skin fibroblast and keratinocyte growth, as well as ... that recombinant EGF enhances keratinocyte migration. EGF is also a potent chemoattractant for granulation tissue fibroblasts

Which of the following statement(s) is/are true concerning pharmacologic agents used to accelerate wound healing? a. A number of these agents are now currently approved for use in this country b. PDGF (platelet-derived growth factor) promotes fibroblast proliferation, chemotaxis, and collagenase synthesis c. PDGF has been demonstrated in a number of clinical trials to promote healing in chronic wounds d. Growth hormone functions by promoting fibroblast proliferation and collagen synthesis

Description : Which of the following statement(s) is/are true concerning pharmacologic agents used to accelerate wound healing? a. A number of these agents are now currently approved for use in ... healing in chronic wounds d. Growth hormone functions by promoting fibroblast proliferation and collagen synthesis

Last Answer : Answer: b, c Currently there are no approved clinical agents that accelerate normal healing. Although a number of clinical trials are in progress, no agents are currently ... hormone administration significantly accelerates donor site healing, presumably due to its effects in minimizing catabolism

Which one of the following is correct? (a) Lymph = Plasma + RBC + WBC (b) Blood = Plasma + RBC + WBC + Platelets (c) Plasma = Blood – Lymphocytes (d) Serum = Blood + Fibrinogen

Description : Which one of the following is correct? (a) Lymph = Plasma + RBC + WBC (b) Blood = Plasma + RBC + WBC + Platelets (c) Plasma = Blood – Lymphocytes (d) Serum = Blood + Fibrinogen

Last Answer : (b) Blood = Plasma + RBC + WBC + Platelets

The first line of host defense is the barrier presented to the external environment. Which of the following statement(s) is/are true concerning host barriers? a. Sebaceous glands secrete chemical compounds that maintain a relatively high pH, providing effective bacterial stasis b. Within the respiratory tract, ciliary function serves to extrude microorganisms trapped within the mucus secretion layer c. The low pH within the stomach markedly decreases bacterial content of the upper gastrointestinal tract d. Gut peristalsis serves to prevent microbial adherence and invasion

Description : The first line of host defense is the barrier presented to the external environment. Which of the following statement(s) is/are true concerning host barriers? a. Sebaceous glands secrete ... of the upper gastrointestinal tract d. Gut peristalsis serves to prevent microbial adherence and invasion

Last Answer : Answer: b, c, d The skin, mucus membranes, and epithelial layers of various organs of the body constitute effective physical barriers against microbial invasion. In certain portions of the ... very low pH within the stomach and gut peristalsis both serve to prevent microbial adherence and invasion

Which of the following statements regarding endothelial cells in acute inflammation are true? a. Endothelial cells are characterized by phenotypic homogeneity b. Specific patterns of receptor expression regulate leukocyte adherence c. Endothelial cell nitric oxide generation regulates regional blood flow and leukocyte adhesion d. Endothelial cells may be capable of phagocytosis

Description : Which of the following statements regarding endothelial cells in acute inflammation are true? a. Endothelial cells are characterized by phenotypic homogeneity b. Specific patterns of receptor expression ... blood flow and leukocyte adhesion d. Endothelial cells may be capable of phagocytosis

Last Answer : Answer: b, c, d Endothelial cells are increasingly recognized to be phenotypically heterogeneous. Specific receptor molecules are expressed at various sites where they help to direct lymphocytes and ... rather, they possess the ability to direct and focus many aspects of an inflammatory event

Which of the following statement(s) is/are true concerning the management of a patient with hemophilia A undergoing an elective surgical operation? a. Concentrates of factor VIII should be given several days prior to elective surgery b. The half-life of factor VIII concentrates is less than 24 hours c. A dose of 40–50 IU/kg of factor VIII concentrate should be given prior to the planned surgical procedure d. Factor VIII concentration administration should be given for the first 24 hours after surgery but may then be stopped if no abnormal bleeding has been observed e. A new recombinant preparation of factor VIII offers the advantage of being virus-free

Description : Which of the following statement(s) is/are true concerning the management of a patient with hemophilia A undergoing an elective surgical operation? a. Concentrates of factor VIII should be given ... observed e. A new recombinant preparation of factor VIII offers the advantage of being virus-free

Last Answer : Answer: b, c, e Although the half-life of factor VIII is 2.9 days in normal individuals, the half-life of factor VIII concentrates is 9 to l8 hours. Levels of 80% to ... infection in the hemophilia population. A new recombinant preparation of factor VIII offers the advantage of being virus-free

Which of the following statement(s) is/are true concerning the physiology of the microvascular system? a. Filtration of capillary fluid into the interstitial and the subsequent reabsorption is influenced by Starling’s law of ultrafiltration b. The most important variable controlling blood to a capillary bed is the length of the vessel c. Most of the resistance to systemic blood flow occurs at the arteriolar level d. Adrenergic vasoconstriction can arrest blood flow to an entire capillary bed

Description : Which of the following statement(s) is/are true concerning the physiology of the microvascular system? a. Filtration of capillary fluid into the interstitial and the subsequent reabsorption is ... the arteriolar level d. Adrenergic vasoconstriction can arrest blood flow to an entire capillary bed

Last Answer : Answer: a, c, d Exchange of material between the vascular space and the cell of various tissues via the interstitial space is essential for organ viability and occurs at the ... contractions are potent enough that blood flow to entire capillary beds can be arrested by adrenergic vasoconstriction

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

Prostaglandins stimulate (A) Aggregation of platelets (B) Lipolysis in adipose tissue (C) Bronchodilatation (D) Gastric acid secretion

Description : Prostaglandins stimulate (A) Aggregation of platelets (B) Lipolysis in adipose tissue (C) Bronchodilatation (D) Gastric acid secretion

Last Answer : Answer : C