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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A woman in active labor is experiencing meconium-stained amniotic fluid. What is the nurse's priority action?
- A. Administer oxygen to the mother.
- B. Prepare for immediate delivery.
- C. Insert a urinary catheter to monitor urine output.
- D. Notify the neonatal resuscitation team.
Correct Answer: B
Rationale: Meconium-stained amniotic fluid indicates that the fetus may have passed stool in utero, which can lead to potential respiratory problems once born due to meconium aspiration. The priority action for the nurse in this situation is to prepare for immediate delivery to expedite the removal of the fetus from the contaminated environment and provide necessary interventions such as suctioning of the airway to prevent aspiration of meconium. Prompt delivery is crucial to minimize the risk of complications related to meconium aspiration syndrome. Administering oxygen, inserting a urinary catheter, and notifying the neonatal resuscitation team can be important subsequent actions, but the immediate focus should be on delivering the baby.
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.
A patient presents with symptoms of polyuria, polydipsia, and polyphagia. Laboratory tests reveal hyperglycemia and glycosuria. Which type of diabetes mellitus is the patient most likely experiencing?
- A. Type 1 diabetes mellitus
- B. Type 2 diabetes mellitus
- C. Gestational diabetes mellitus
- D. Latent autoimmune diabetes in adults (LADA)
Correct Answer: A
Rationale: The patient is most likely experiencing Type 1 diabetes mellitus based on the presentation of polyuria, polydipsia, polyphagia, hyperglycemia, and glycosuria. Type 1 diabetes is characterized by autoimmune destruction of the beta cells in the pancreas, leading to absolute insulin deficiency. This results in high blood sugar levels (hyperglycemia) and glucose spilling into the urine (glycosuria). Patients with Type 1 diabetes often present with the classic symptoms of polyuria (increased urination), polydipsia (increased thirst), and polyphagia (increased hunger) due to the body's inability to utilize glucose for energy effectively. Management of Type 1 diabetes typically involves lifelong insulin therapy to maintain blood sugar levels within a target range.
A patient presents with a yellowish-white spot on the cornea, surrounded by a ring of inflammation. Slit-lamp examination reveals branching, filamentous opacities extending from the corneal lesion. Which of the following conditions is most likely responsible for this presentation?
- A. Herpes simplex keratitis
- B. Bacterial keratitis
- C. Fungal keratitis
- D. Acanthamoeba keratitis
Correct Answer: C
Rationale: The described clinical presentation of a yellowish-white spot on the cornea with a ring of inflammation, along with branching, filamentous opacities extending from the corneal lesion, is highly suggestive of fungal keratitis. Fungal keratitis is commonly caused by filamentous fungi such as Fusarium and Aspergillus species. The characteristic finding of branching, filamentous opacities seen on slit-lamp examination is classic for fungal infections of the cornea. It is important to promptly diagnose and treat fungal keratitis since delayed or inadequate management can result in vision-threatening complications.
The nurse did an admission procedure. The best position to be assumed by Roy is _____.
- A. left lateral position with the affected side inferior.
- B. semi-fowler position at least 30 degrees.
- C. dorsal position with pillows under the chest.
- D. lying on his side, the affected side of the lungs should be superior.
Correct Answer: B
Rationale: The best position for a patient to assume during an admission procedure, particularly for respiratory assessment, is the semi-fowler position at least 30 degrees. In the semi-fowler position, the patient's head and upper body are elevated to a 30-degree angle. This position helps improve lung expansion and oxygenation by reducing pressure on the diaphragm and enhancing chest expansion. It also facilitates breathing and allows for better assessment of respiratory status. Additionally, the semi-fowler position helps prevent aspiration and promotes comfort and relaxation for the patient during the admission procedure.