Nokea
Which of the following are not typically found within secondary lymphoid tissues?
- A. naïve lymphocytes
- B. Hematopoietic stem cells
- C. Dendritic cells
- D. Antigen
Correct Answer: B
Rationale: Correct Answer: B - Hematopoietic stem cells are not typically found within secondary lymphoid tissues because they are located in the bone marrow where they give rise to various blood cells. In contrast, secondary lymphoid tissues like lymph nodes and spleen primarily consist of mature immune cells and support immune responses. Naïve lymphocytes (A), dendritic cells (C), and antigens (D) are commonly found in secondary lymphoid tissues as they play crucial roles in the immune response.
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A patient with wheezing and coughing caused by an allergic reaction to penicillin is admitted to the emergency department (ED). Which of these medications do you anticipate administering first?
- A. methylprednisolone (Solu-Medrol) 100 mg IV
- B. cromolyn sodium (Intal) 20 mg per nebulizer
- C. albuterol (Proventil) 0.5 mL per nebulizer
- D. aminophylline 500 mg IV over 20 minutes
Correct Answer: C
Rationale: Albuterol is a bronchodilator that acts quickly to relieve wheezing and coughing caused by bronchospasm. It is the first-line treatment for acute allergic reactions affecting the airways. The other medications may be used as adjuncts but are not as immediately effective in relieving bronchospasm.
Virulence factors can be transferred from pathogenic to non-pathogenic bacterial strains that are part of the normal flora. An example of a commensal bacterial species that has turned into a pathogenic strain is:
- A. E. coli 0157:H7
- B. M. tuberculosis
- C. Group A S. pyogenes
- D. All opportunistic bacterial species
Correct Answer: A
Rationale: The correct answer is A: E. coli 0157:H7. This strain of E. coli has acquired virulence factors that allow it to cause severe illness in humans, such as bloody diarrhea and kidney failure. The transformation of E. coli from a commensal to a pathogenic strain is well-documented. In contrast, choices B and C involve species that are inherently pathogenic and not commensal. Choice D is too broad and includes a wide range of bacterial species that do not necessarily originate from the normal flora. Therefore, E. coli 0157:H7 is the best example of a commensal bacterium that has turned pathogenic due to the acquisition of virulence factors.
Which hypersensitivity type is mediated by T cells?
- A. Type I
- B. Type II
- C. Type III
- D. Type IV
Correct Answer: D
Rationale: The correct answer is D: Type IV hypersensitivity. This type is mediated by T cells, specifically CD4+ helper T cells and CD8+ cytotoxic T cells. The process involves antigen-presenting cells activating T cells, leading to a delayed response. Choices A, B, and C involve different mechanisms and are not mediated by T cells. Type I is mediated by IgE antibodies, Type II involves antibody-mediated cell destruction, and Type III involves immune complex deposition. Therefore, Type IV is the only hypersensitivity type directly mediated by T cells.
The nurse realizes that the patient understands the teaching about decreasing the risk for antibiotic-resistant infection when the patient says which of the following?
- A. I know I should take the antibiotic for one day after I feel better.
- B. I want an antibiotic ordered for my cold so I can feel better sooner.
- C. I always save some pills because I get the illness again after I first feel better.
- D. I will follow the directions for taking the antibiotic so I will get over this infection.
Correct Answer: D
Rationale: Following the prescribed regimen ensures complete eradication of the infection and reduces the risk of resistance development.
A confirmatory lab test for HIV includes:
- A. Western blot.
- B. Low WBC.
- C. Comprehensive metabolic panel.
- D. Enzyme-linked immunosorbent assay (ELISA).
Correct Answer: A
Rationale: The Western blot test is considered the gold standard for confirming HIV infection after initial screening tests like ELISA. Low WBC and comprehensive metabolic panels are not specific to HIV diagnosis.