The blood-brain barrier, which restricts entry of many drugs into brain, is constituted by: A. P-glycoprotein efflux carriers in brain capillary cells B. Tight junctions between endothelial cells of brain capillaries C. Enzymes present in brain capillary walls D. All of the above

1 Answer

Answer :

D. All of the above

Related questions

Description : The blood-brain barrier, which restricts entry of many drugs into brain, is constituted by: A. P-glycoprotein efflux carriers in brain capillary cells B. Tight junctions between endothelial cells of brain capillaries C. Enzymes present in brain capillary walls D. All of the above

Last Answer : D. All of the above

Description : 6 The blood-brain barrier, which restricts entry of many drugs into brain, is constituted by: A. P-glycoprotein efflux carriers in brain capillary cells B. Tight junctions between endothelial cells of brain capillaries C. Enzymes present in brain capillary walls D. All of the above

Last Answer : D. All of the above

Description : Which of the following is not true of the blood-brain barrier: A. It is constituted by tight junctions between the endothelial cells of brain capillaries and the glial tissue B. It allows passage ... of highly ionized drugs into the brain D. It regulates passage of substances from brain into blood

Last Answer : D. It regulates passage of substances from brain into blood

Description : Which of the following is not true of the blood-brain barrier: A. It is constituted by tight junctions between the endothelial cells of brain capillaries and the glial tissue B. It allows passage ... of highly ionized drugs into the brain D. It regulates passage of substances from brain into blood

Last Answer : D. It regulates passage of substances from brain into blood

Description : Which of the following is not true of the blood-brain barrier: A. It is constituted by tight junctions between the endothelial cells of brain capillaries and the glial tissue B. It allows passage ... of highly ionized drugs into the brain D. It regulates passage of substances from brain into blood

Last Answer : D. It regulates passage of substances from brain into blood

Description : Weakly acidic drugs: A. Are bound primarily to α1 acid glycoprotein in plasma B. Are excreted faster in alkaline urine C. Are highly ionized in the gastric juice D. Do not cross blood-brain barrier

Last Answer : B. Are excreted faster in alkaline urine

Description : Weakly acidic drugs: A. Are bound primarily to α1 acid glycoprotein in plasma B. Are excreted faster in alkaline urine C. Are highly ionized in the gastric juice D. Do not cross blood-brain barrier

Last Answer : B. Are excreted faster in alkaline urine

Description : The most important factor which governs diffusion of drugs across capillaries other than those in the brain is: A. Blood flow through the capillary B. Lipid solubility of the drug C. pKa value of the drug D. pH of the medium

Last Answer : A. Blood flow through the capillary

Description : The most important factor which governs diffusion of drugs across capillaries other than those in the brain is: A. Blood flow through the capillary B. Lipid solubility of the drug C. pKa value of the drug D. pH of the medium

Last Answer : A. Blood flow through the capillary

Description : The blood-brain-barrier: a. contains the foot processes of astrocytes b. contains endothelial cells with tight junction c. allows transport in one direction only ie from the vascular system into the brain d. does not allow diffusion of water

Last Answer : does not allow diffusion of water

Description : The following are true about blood-brain barrier: a. it is permeable at birth b. it involves tight junction between endothelial cells and end feet processes of astrocytes c. it is absent in the posterior pituitary d. all above

Last Answer : all above

Description : The blood - brain barrier: a. is permeable to bilirubin at birth b. is formed by the tight junctions between endothlial cells and the end feet processes of astrocytes c. is permeable to glucose d. all above

Last Answer : all above

Description : The blood - brain barrier: a. is permeable to bilirubin at birth b. is formed by the tight junctions between endothlial cells and the end feet processes of astrocytes c. is permeable to glucose d. all above

Last Answer : all above

Description : With regard to the blood retina barrier: a. the outer blood retina is formed by the retinal pigment epithelium cells and their junctions b. the blood retina barrier is typically defective in the ... fluid and anions from the extracellular space of the retina into the circulation d. all above

Last Answer : all above

Description : Neuromuscular blocking drugs do not produce central actions because: A. They do not cross the blood-brain barrier B. Nicotinic receptors are not present in the brain C. They are sequestrated in the periphery by tight binding to the skeletal muscles D. They do not ionise at the brain pH

Last Answer : A. They do not cross the blood-brain barrier

Description : Weakly acidic drugs: A. Are bound primarily to α1 acid glycoprotein in plasma B. Are excreted faster in alkaline urine C. Are highly ionized in the gastric juice D. Do not cross blood-brain barrier

Last Answer : B. Are excreted faster in alkaline urine

Description : Neostigmine is preferred over physostigmine for treating myasthenia gravis because: A. It is better absorbed orally B. It has longer duration of action C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate D. It penetrates blood-brain barrier

Last Answer : C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate

Description : The pharmacokinetics of drugs in the neonate differs from that in adults, because their: A. Intestinal transit is fast B. Drug metabolizing enzymes are overactive C. Tubular transport mechanisms are not well developed D. Glomerular filtration rate is high

Last Answer : C. Tubular transport mechanisms are not well developed

Description : The pharmacokinetics of drugs in the neonate differs from that in adults, because their: A. Intestinal transit is fast B. Drug metabolizing enzymes are overactive C. Tubular transport mechanisms are not well developed D. Glomerular filtration rate is high

Last Answer : C. Tubular transport mechanisms are not well developed

Description : Wall of blood capillary is formed of (a) haemocytes (b) parietal cells (c) endothelial cells (d) oxyntic cells.

Last Answer : c) endothelial cells

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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

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

Description : What is true in relation to drug receptors: A. All drugs act through specific receptors B. All drug receptors are located on the surface of the target cells C. Agonists induce a conformational change in the receptor D. Partial agonists have low affinity for the receptor

Last Answer : C. Agonists induce a conformational change in the receptoR

Description : What is true in relation to drug receptors: A. All drugs act through specific receptors B. All drug receptors are located on the surface of the target cells C. Agonists induce a conformational change in the receptor D. Partial agonists have low affinity for the receptor

Last Answer : C. Agonists induce a conformational change in the receptor

Description : `Essential drugs’ are: A. Life saving drugs B. Drugs that meet the priority health care needs of the population C. Drugs that must be present in the emergency bag of a doctor D. Drugs that are listed in the pharmacopoia of a country

Last Answer : B. Drugs that meet the priority health care needs of the population

Description : `Essential drugs’ are: A. Life saving drugs B. Drugs that meet the priority health care needs of the population C. Drugs that must be present in the emergency bag of a doctor D. Drugs that are listed in the pharmacopoia of a country

Last Answer : B. Drugs that meet the priority health care needs of the population

Description : 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 ... adjacent cells d. Gap junctions are a type of cell junction specialized for cell communication

Last Answer : 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 ... gap junction which is specialized for communication. This junction mediates both electrical and chemical coupling

Description : The following statement is not correct for uremic patients: A. Attainment of steady-state plasma concentration of drugs eliminated through the kidney is hastened B. Pethidine can cause seizures C. Diazepam produces exaggerated CNS depression D. Tetracyclines further raise blood urea level

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Description : Monitoring of blood levels of diuretic drugs is not practised because: A. No sensitive methods for measuring blood levels of diuretics are available B. It is easier to measure the effect of these ... Response to diuretics is not related to their blood levels D. Diuretics need activation in the body

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Description : The following statement is not correct for uremic patients: A. Attainment of steady-state plasma concentration of drugs eliminated through the kidney is hastened B. Pethidine can cause seizures C. Diazepam produces exaggerated CNS depression D. Tetracyclines further raise blood urea level

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Description : Monitoring of blood levels of diuretic drugs is not practised because: A. No sensitive methods for measuring blood levels of diuretics are available B. It is easier to measure the effect of these ... Response to diuretics is not related to their blood levels D. Diuretics need activation in the body

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Description : The following are true about micro-circulation: a. arterioles have no muscle b. capillaries have walls made up of a single layer of cells c. capillaries have no innervation d. the capillaries contain 5% of the total blood volume at any one time

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Description : Induction of drug metabolizing enzymes involves: A. A conformational change in the enzyme protein to favour binding of substrate molecules B. Expression of enzyme molecules on the surface of ... C. Enhanced transport of substrate molecules into hepatocytes D. Increased synthesis of enzyme protein

Last Answer : D. Increased synthesis of enzyme protein

Description : Induction of drug metabolizing enzymes involves: A. A conformational change in the enzyme protein to favour binding of substrate molecules B. Expression of enzyme molecules on the surface of ... C. Enhanced transport of substrate molecules into hepatocytes D. Increased synthesis of enzyme protein

Last Answer : D. Increased synthesis of enzyme protein

Description : Sulfamethoxypyridazine and other related long acting sulfonamides have now gone into disuse because (a) They have produced serious cutaneous reactions (b) They have produced high incidence of crystalluria (c) They interact with many drugs (d) They do not penetrate blood-brain barrier

Last Answer : Ans: A

Description : Biotransformation of drugs is primarily directed to: A. Activate the drug B. Inactivate the drug C. Convert lipid soluble drugs into nonlipid soluble metabolites D. Convert nonlipid soluble drugs into lipid soluble metabolites

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Description : Biotransformation of drugs is primarily directed to: A. Activate the drug B. Inactivate the drug C. Convert lipid soluble drugs into nonlipid soluble metabolites D. Convert nonlipid soluble drugs into lipid soluble metabolites

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Description : Muscarinic cholinergic receptors: A. Are located only on parasympathetically innervated effector cells B. Mediate responses by opening an intrinsic Na+ ion channel C. Are present on vascular endothelium which has no cholinergic nerve supply D. Predominate in the autonomic ganglia

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Description : Which of the following types of drug metabolizing enzymes are inducible: A. Microsomal enzymes B. Nonmicrosomal enzymes C. Both microsomal and nonmicrosomal enzymes D. Mitochondrial enzymes

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Last Answer : D. Tubular transport mechanisms are not well developed

Description : Which of the following types of drug metabolizing enzymes are inducible: A. Microsomal enzymes B. Nonmicrosomal enzymes C. Both microsomal and nonmicrosomal enzymes D. Mitochondrial enzymes

Last Answer : A. Microsomal enzymes

Description : Barrier potential in a P-N junction is caused by (A) Thermally generated electrons and holes. (B) Diffusion of majority carriers across the junction. (C) Migration of minority carriers across the junction. (D) Flow of drift current.

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Description : The most vulnerable period of pregnancy for the causation of foetal malformations due to drugs is: A. 18-55 days of gestation B. 56-84 days of gestation C. Second trimester D. 36 weeks onwards

Last Answer : A. 18-55 days of gestation

Description : The following statement is true in relation to drug toxicity' and poisoning': A. The two terms are synonymous B. When a toxic effect requires specific treatment, it is called poisoning C. ... is called poisoning D. Toxicity is caused by drugs while poisoning is caused by other harmful chemicals

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Description : In congestive heart failure patients: A. Volume of distribution of all drugs is increased B. Hepatic clearance of drugs is unaffected C. Orally administered diuretics may not be effective, but the same may work parenterally D. Inotropic action of digoxin is attenuated

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Description : In patients of hepatic cirrhosis: A. The extent of change in pharmacokinetics of drugs can be predicted from the values of liver function tests B. High doses of furosemide can be safely used C. Metformin is the preferred oral hypoglycaemic D. Disposition of atenolol is not significantly affected

Last Answer : D. Disposition of atenolol is not significantly affected

Description : If the effect of combination of two drugs is equal to the sum of their individual effects, the two drugs are exhibiting: A. Potentiation B. Synergism C. Cross tolerance D. Antagonism

Last Answer : B. Synergism