A 7-Month-Old Boy,the Only Child of Second-Degree Cousins,saw a Pediatrician $\alpha$

question 8

Multiple Choice

A 7-month-old boy,the only child of second-degree cousins,saw a pediatrician for immunologic evaluation after developing Pneumocystis carinii pneumonia.Serum IgG,IgM,and IgA levels were normal.Blood cell count showed 10,600 leukocytes/mm³ and 80% lymphocytes;90% of the lymphocytes were TCR $\alpha$$\beta$ ⁺CD4⁺.In vitro lymphocyte-proliferative responses to PHA and anti-CD3 were absent,and the pattern of tyrosine-phosphorylated cytoplasmic proteins after anti-CD3 treatment of the T cells was distinctly abnormal.This boy most likely carries homozygous mutations in the gene encoding which one of the following proteins?

• A)Zap-70
• B)RAG-1
• C)CD3
• D)Pre-T\(\alpha\)
• E)TCR\(\alpha\)

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Definitions:

Job Rotation

Involves periodically moving employees through a variety of positions or tasks to enhance their skills and prevent job monotony.

Modified Assembly-Line

A production process that has been adjusted or customized from the traditional assembly-line method to improve efficiency, flexibility, or worker satisfaction.

Good Job Design

The process of organizing work tasks and responsibilities to improve job satisfaction and performance.

Task Requirements

The specific duties, responsibilities, and conditions necessary to successfully complete a job or task.