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Nifedipine is an antihypertension medication that is also used to reduce the workload on the heart. The study below compares the effects of two different types of capsules used to administer the drug to patients (GITS—red line, and Cotracten X—blue line). Each graph shows changes with time following initial administra- tion of the capsules. Figure A compares the levels of nifedipine in the blood with each capsule type. The ability of the different cap- sules to reduce workload on the heart by altering blood pressure or heart rate is shown in Figures B and C, respectively.
Are elevated plasma levels of nifedipine(above 10 ng/mL) required for the drug to perform its actions?
Source: M. J. Brown and C. B. Toal. 2008. Formulation of long-acting nifedipine tablets influences the heart rate and sympathetic nervous system response in hypertensive patients. British Journal of Clinical Pharmacology 65:646–652.
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Chapter 44 Solutions
Biology: The Dynamic Science (MindTap Course List)
- Nifedipine is an antihypertension medication that is also used to reduce the workload on the heart. The study below compares the effects of two different types of capsules used to administer the drug to patients (GITSred line, and Cotracten Xblue line). Each graph shows changes with time following initial administra- tion of the capsules. Figure A compares the levels of nifedipine in the blood with each capsule type. The ability of the different cap- sules to reduce workload on the heart by altering blood pressure or heart rate is shown in Figures B and C, respectively. Which type of capsule would you expect to have fewer side effects? Source: M. J. Brown and C. B. Toal. 2008. Formulation of long-acting nifedipine tablets influences the heart rate and sympathetic nervous system response in hypertensive patients. British Journal of Clinical Pharmacology 65:646652.arrow_forwardConsider each of the following endpoints and identify whether it is dichotomous (binary) or continuous: Group of answer choices Diastolic Blood Pressure 3 months after beginning medication A。Binary B。continuous Diagnosis: patient does/does not have cancer A。Binary B。continuous Patient achieves normal diastolic blood pressure within 30 days of starting a drug, or not A。Binary B。continuous FEV1 (forced expiratory volume in 1 second—the amount of air expelled from a patient against pressure within 1 second) A。Binary B。continuous Weight loss between baseline and 6 months A。Binary B。continuous Concentration of hemoglobin in a blood sample A。Binary B。continuous…arrow_forwardA Physician orders 40 mL of an IV solution containing ampicillin to run in 30 minutes with a microdrop infusion set. This is to be followed by 500 mL of NS to infuse at 50 drops per minute with an infusion set of 20 gtt/mL. What is the total infusion time for the two IV solutions?arrow_forward
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- Hyperglycemia associated with diabetes promotes a prothrombotic state by affecting a number of different steps in the clotting pathway. Which of the following would result in more rather than less clotting? Check all that apply. The correct answers reflect the effect of hyperglycemia on the clotting pathway! less conversion of plasminogen to plasmin 7 000000000 abnormally low number of platelets platelets more sensitive to thromboxane A2 elevated conversion of plasminogen to plasmin platelets less sensitive to thromboxane A2 low sensitivity to NO and PGI2 increased prothrombin in the blood increased amount of fibrinogen in the blood less prothrombin in the blood abnormally high number of platelets less fibrinogen in the blood high sensitivity to NO and PGI2arrow_forward1) Explain the principle of the electrical impedance cell counting. 2) State 3 Haematology analyzer and their manufacturers. 3) CV for automated instrument is +/- 1% to +/- 2% compared to manual count with CV +/- 10%. Can you explain their differences?arrow_forwardOne way of reducing risk of cardiovascular disease is to ensure you are getting lots of antioxidants in your diet. What antioxidants would you recommend and not recommend for someone at risk of cardiovascular disease that is also on medication that interferes with their blood’s clotting mechanism? Explain the reasons for your recommendations in one to two paragraphs. Also, list three medical conditions that can alter a person's vitamin requirements. Explain what vitamin/s would be affected and how they should alter their dietary from normal recommendations.arrow_forward
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