For increasing blood pressure in case of low cardiac output the following agents must be used:

Correct Answer: C

Rationale: To increase blood pressure in low cardiac output, positive inotropic drugs (Choice C) are used to improve the heart's contractility and increase cardiac output. Ganglioblockers (Choice A) block sympathetic activity, potentially worsening low cardiac output. Vasoconstrictors (Choice B) can increase blood pressure but may not address the underlying cause of low cardiac output. Diuretics (Choice D) reduce blood volume and may further decrease cardiac output. Therefore, Choice C is the correct option to address low cardiac output by improving heart function and increasing blood pressure.

Correct Answer: A

Rationale: Estrogens have immunomodulatory properties by enhancing immune responses, while progestins have immunosuppressive effects by inhibiting immune responses. Therefore, the statement is TRUE. Choice B is incorrect because the statement is not false. Choice C is incorrect as it does not provide a clear answer. Choice D is incorrect as it does not apply in this scenario.

Correct Answer: B

Rationale: The correct answer is B because adaptive immunity is characterized by antigen-specific defense mechanisms that target and eliminate specific pathogens. This type of immunity takes time to develop, usually several days, and involves the activation of lymphocytes such as T and B cells that can recognize and respond to specific antigens. This process leads to the formation of memory cells that provide long-lasting protection against future encounters with the same antigen. Choices A, C, and D are incorrect: A: This describes innate (natural) immunity, which is present at birth and provides immediate, nonspecific defense mechanisms against pathogens. C: Interferons are signaling proteins produced in response to viral infections and are part of the innate immune response, not adaptive immunity. D: Immunosuppressive agents are drugs that suppress the immune system and are used to prevent rejection of transplanted organs or treat autoimmune diseases. They do not enhance adaptive immunity.

Correct Answer: C

Rationale: The correct answer is C because it accurately defines what vitamins are: essential organic substances needed in small amounts for normal growth and activity. Vitamins are obtained naturally from plant and animal foods. Choice A is incorrect because vitamins are organic, not inorganic. Choice B is incorrect because vitamins are needed in small quantities, not very large. Choice D is incorrect because vitamins are not products of endocrine gland secretion.

Correct Answer: A

Rationale: Physostigmine is the correct answer as it is a cholinesterase inhibitor. Cholinesterase inhibitors prevent the breakdown of acetylcholine, leading to increased cholinergic activity. Physostigmine specifically inhibits both acetylcholinesterase and butyrylcholinesterase. This action results in increased levels of acetylcholine in the synaptic cleft, enhancing cholinergic transmission. This mechanism is used in the treatment of conditions such as myasthenia gravis and glaucoma. Selegiline (B) is a monoamine oxidase inhibitor used in the treatment of Parkinson's disease. Aminocaproic acid (C) is an antifibrinolytic agent used to treat excessive bleeding. Disulfiram (D) is an alcohol deterrent used in the management of alcohol dependence by inhibiting aldehyde dehydrogenase. These choices are incorrect as they do not act as cholinesterase inhibitors.