Resident microflora is found in

Correct Answer: C

Rationale: The correct answer is C: urethra. Resident microflora refers to the normal, beneficial bacteria that inhabit a specific area of the body without causing harm. The urethra is one of the locations where resident microflora are commonly found. These bacteria play a vital role in maintaining a healthy balance and preventing harmful pathogens from colonizing the urethra. Blood (A), lung (B), and cerebro-spinal fluid (D) are not typical locations for resident microflora as these areas are usually sterile or have very limited microbial presence to prevent infections.

Correct Answer: B

Rationale: Answer B, Infectious mononucleosis, is not caused by enteroviruses. Infectious mononucleosis is primarily caused by the Epstein-Barr virus, a member of the herpesvirus family, not by enteroviruses. Enteroviruses are known to cause diseases such as myocarditis, herpangina, and Boston exanthema. Therefore, B is the correct answer. Myocarditis, herpangina, and Boston exanthema can all be caused by enteroviruses, making choices A, C, and D incorrect, respectively.

Correct Answer: A

Rationale: The correct answer is A: Botulism. Botulism is caused by the toxin produced by Clostridium botulinum bacteria found in improperly preserved or canned foods. The symptoms described align with botulism, such as difficulty swallowing and breathing due to muscle paralysis. The tennis racket appearance seen under microscopy corresponds to the characteristic appearance of Clostridium botulinum spores. The other choices can be ruled out based on the clinical presentation and microscopy findings. Cholera typically presents with severe watery diarrhea, Nontyphoidal Salmonella infection with fever and gastrointestinal symptoms, and Typhoid fever with high fever and abdominal pain. Therefore, the most likely diagnosis in this case is botulism.

Correct Answer: D

Rationale: Step 1: Mantoux test measures cell-mediated immunity response to tuberculosis. Step 2: A negative result means no significant immune response to TB antigens. Step 3: Option A is incorrect, as it refers to antitoxic immunity, not cell immunity. Step 4: Option B is incorrect, as it mentions antibodies, not cell-mediated immunity. Step 5: Option C is incorrect, as it states absence of antibodies, not cell immunity. Step 6: Option D is correct as it directly correlates with the purpose of Mantoux test.

Correct Answer: B

Rationale: The correct answer is B: septicemia. Septicemia specifically refers to the presence of bacteria in the bloodstream, leading to a systemic inflammatory response. Bacteremia (choice A) is simply the presence of bacteria in the blood without the systemic inflammatory response. Shock (choice C) is a state of circulatory collapse, often seen in severe septicemia. Bloodborne infection (choice D) is a general term for infections transmitted through the blood but does not specifically refer to the condition of bacterial multiplication causing toxicity.

Correct Answer: A

Rationale: The correct answer is A: Anatoxin. An anatoxin is a preparation that contains inactivated toxins produced by the anthrax-causing bacteria. By administering anatoxin, the population can develop immunity against the toxin without being exposed to the live bacteria. This specific prophylaxis approach helps prevent the development of anthrax infection by targeting the toxin itself. Summary: - Choice B (Inactivated vaccine) is incorrect because an inactivated vaccine typically contains killed or inactivated whole bacteria, not just the toxins. - Choice C (Chemical vaccine) is incorrect as there is no such thing as a chemical vaccine; vaccines are biological preparations. - Choice D (Genetically engineered vaccine) is incorrect because while vaccines can be genetically engineered, the specific term "genetically engineered vaccine" does not accurately describe the prophylaxis used against anthrax in this scenario.

Correct Answer: D

Rationale: Certainly! The correct answer is D because all three options (A, B, and C) can be analyzed in the diagnosis of sexually transmitted infections. Genital ulcer secretions can reveal the presence of pathogens causing STIs, lymph node punctate can indicate systemic infection, and serum can be tested for specific STI antibodies. Therefore, all these clinical specimens are essential for a comprehensive diagnosis of sexually transmitted infections. The other choices (A, B, C) are incorrect as they individually represent important specimens used in the diagnosis process.

Correct Answer: A

Rationale: Rationale: The correct answer is A: Trichomonas vaginalis. 1. Symptoms of urogenital inflammation match Trichomonas vaginalis infection. 2. Description matches Trichomonas vaginalis characteristics: pear-shaped, pointed spike, big nucleus, undulating membrane. 3. Trichomonas hominis and buccalis do not typically infect urogenital tracts. 4. Trypanosoma gambiense causes African trypanosomiasis, not urogenital infections.

Correct Answer: B

Rationale: The correct answer is B because reinfection is indeed possible with rabies virus. Step 1: Reinfection occurs if a person is exposed to the virus again after initial infection. Step 2: Once infected, the virus can remain dormant in the body and become active upon re-exposure. Step 3: Therefore, it is essential to continue preventive measures even after initial immunization. Summary: Choices A, C, and D are incorrect because antibodies develop within 14-15 days post-immunization, HRIG is administered shortly after exposure, and a specific vaccination schedule is followed for rabies prophylaxis, respectively.