Nokea
Which of the following statements accurately describes the role of major histocompatibility complex (MHC) molecules in antigen presentation?
- A. MHC class I molecules present exogenous antigens to CD4+ T cells.
- B. MHC class I molecules present endogenous antigens to CD8+ T cells.
- C. MHC class II molecules present endogenous antigens to CD4+ T cells.
- D. MHC class II molecules present exogenous antigens to CD8+ T cells.
Correct Answer: B
Rationale: Major histocompatibility complex (MHC) class I molecules are responsible for presenting endogenous antigens, such as viral or intracellular proteins, to CD8+ T cells. These antigens are derived from within the cell, either synthesized within the cell itself or taken up from the cytoplasm. CD8+ T cells, also known as cytotoxic T cells, recognize antigens presented by MHC class I molecules and play a key role in cell-mediated immunity by destroying infected or abnormal cells.
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Nurse Selma is preparing to administer ofloxacin eardrop on Catherine per Doctor's order. She needs to hold the bottle with her hands to warm up the solution to prevent dizziness for
- A. 5-6 minutes
- B. 1 to 2 minutes
- C. 3-4 minutes
- D. 6-7 minutes
Correct Answer: B
Rationale: Warming up ofloxacin eardrops before administering is done to prevent dizziness, which can occur if a cold solution is placed in the ear. Holding the bottle with hands for about 1 to 2 minutes is usually sufficient to warm up the solution to a comfortable temperature for the patient. Warming the solution for too long, such as 5-6 minutes, may not be necessary and could potentially waste time. So, the correct duration for warming up ofloxacin eardrops is 1 to 2 minutes.
The female client who is very anxious and fidgety is blowing off to much carbon dioxide develops tingling sensation of the lips and fingers and is not able to control her respirations. The MOST appropriate nursing intervention for this client is to _____.
- A. Instruct the client to blow her nose and take deep breath
- B. Administer oxygen
- C. Have the client breath into a paper bag
- D. Administer IV fluids as ordered
Correct Answer: C
Rationale: The client is experiencing symptoms of hyperventilation, a condition that occurs when there is excessive elimination of carbon dioxide from the body. Breathing into a paper bag can help by allowing the client to rebreathe carbon dioxide, which can help restore the balance of gases in the blood and alleviate the tingling sensations in the lips and fingers. This technique is commonly used to help regulate breathing in cases of hyperventilation. Administering oxygen (choice B) may not be necessary as the issue lies with an imbalance of carbon dioxide, not a lack of oxygen. Instructing the client to blow her nose and take deep breaths (choice A) may not address the underlying problem effectively. Administering IV fluids (choice D) is not relevant to the client's symptoms of hyperventilation.
As a nurse you are guided that pain is usually described BEST as a phenomenon which is a ________.
- A. Neurologic activation nociceptors
- B. Subjective unpleasant experience
- C. Adaptive mechanism to a stimulus
- D. Creation of one's imagination
Correct Answer: B
Rationale: Pain is best described as a subjective unpleasant experience because it is unique to each individual and is influenced by a variety of factors including emotional, psychological, and cultural elements. Pain cannot be objectively measured or quantified, and therefore it is considered a subjective experience that is reported by the person experiencing it. This is why pain is often assessed using self-report scales and tools to capture the individual's perception of their pain intensity and quality.
Which of the following study designs that uses information on current health status, personal characteristics, and potential risk factors will be appropriate?
- A. Case-control
- B. Cohort
- C. Ecological
- D. Cross-sectional
Correct Answer: B
Rationale: A cohort study design would be appropriate in this scenario. Cohort studies follow a group of individuals over a period of time to assess how their current health status, personal characteristics, and potential risk factors may contribute to the development of certain outcomes or diseases. By collecting data at different time points on the same group of individuals, cohort studies allow researchers to establish associations between exposures and outcomes, providing valuable information on causality. In this case, using a cohort study design would allow for a comprehensive examination of how various factors impact health outcomes over time.
A 70- year-old has been rushed to the hospital due to bradycardia and palpitation. The physician suggested that a pacemaker be inserted to correct the symptoms. The patient voluntarily decides not to have the pacemaker Inserted. This is respected by the family. This is an example of what ethical principles
- A. Beneficence
- B. Autonomy
- C. Fidelity
- D. Justice
Correct Answer: B
Rationale: Autonomy is the ethical principle that respects an individual's right to make their own decisions about their medical treatment, even if it goes against medical advice or the preferences of others. In this case, the 70-year-old patient has voluntarily decided not to have the pacemaker inserted despite the physician's recommendation. The fact that the patient's decision is respected by the family reflects the importance of honoring the patient's autonomy and right to make decisions about their own healthcare.