Biochemistry
1 questionsIn patients with Retinitis pigmentosa, which of the following substances is known to have decreased levels?
NEET-PG 2019 - Biochemistry NEET-PG Practice Questions and MCQs
Question 141: In patients with Retinitis pigmentosa, which of the following substances is known to have decreased levels?
- A. Thromboxane
- B. Arachidonic acid
- C. Docosahexaenoic acid (DHA) (Correct Answer)
- D. Linoleic acid
Explanation: ***Docosahexaenoic acid (DHA)*** - **Docosahexaenoic acid (DHA)** is a crucial **omega-3 fatty acid** abundantly found in the **photoreceptor cell membranes**, particularly in the retina. - Reduced levels of DHA are frequently observed in patients with **retinitis pigmentosa**, suggesting its role in disease pathogenesis and retinal health. *Arachidonic acid* - **Arachidonic acid** is an **omega-6 fatty acid** and a precursor to many signaling molecules, but its levels are **not typically decreased** in retinitis pigmentosa. - It plays a **pro-inflammatory role** and is involved in various physiological processes, distinct from the primary metabolic defects in retinitis pigmentosa. *Linoleic acid* - **Linoleic acid** is an essential **omega-6 fatty acid** and a precursor to arachidonic acid, but its deficiencies are not characteristic of retinitis pigmentosa. - It is crucial for **skin barrier function** and overall health, but its metabolic pathways are distinct from those primarily affected in retinal degenerations. *Thromboxane* - **Thromboxane** is a **lipid mediator** primarily involved in **platelet aggregation** and vasoconstriction. - It is not directly associated with the metabolic pathways or structural integrity of the retina, and its levels are not typically altered in retinitis pigmentosa.
Forensic Medicine
1 questionsIn the context of gunshot injuries, which of the following describes the characteristics of a close shot entry wound, including signs such as burning, blackening, tattooing around the wound, and the presence of a dirt collar?
NEET-PG 2019 - Forensic Medicine NEET-PG Practice Questions and MCQs
Question 141: In the context of gunshot injuries, which of the following describes the characteristics of a close shot entry wound, including signs such as burning, blackening, tattooing around the wound, and the presence of a dirt collar?
- A. Close shot exit wound
- B. Distant shot entry wound
- C. Distant shot exit wound
- D. Close shot entry wound (Correct Answer)
Explanation: ***Close shot entry wound*** - **Burning, blackening, tattooing**, and a **dirt collar** around the wound are classic signs of a **close-range gunshot entry wound**. These findings result from the burning of skin by hot gases, deposition of soot (blackening), and impact of unburnt gunpowder particles (tattooing/stippling) from a firearm discharged at a close distance. - The **"dirt collar"** (also known as a **grease collar** or **abrasion collar**) is caused by the passage of the bullet through the skin, wiping off lubricants, dirt, and residue from the bullet onto the skin around the wound. *Close shot exit wound* - An **exit wound** is typically larger, more irregular, and lacks the characteristics of burning, blackening, or tattooing because the bullet has lost momentum and often tumbles or deforms as it exits the body. - There would also be no dirt collar or soot deposits, as these are associated with the initial entry of the bullet and propellant gases. *Distant shot entry wound* - A **distant shot entry wound** would likely show an abrasion collar and a circular or oval defect, but it would lack the burning, blackening (soot), and tattooing (stippling) as the firearm was discharged from a distance preventing these elements from reaching the skin. - The lack of unburnt powder and gases impacting the skin differentiates it from a close-range shot. *Distant shot exit wound* - A **distant shot exit wound** would exhibit the same characteristics as any exit wound: larger, irregular, and without the signs of burning, blackening, or tattooing. - The absence of close-range effects like soot and stippling on a distant entry wound similarly means they would not be present on a distant exit wound.
Internal Medicine
3 questionsWhich murmur increases on standing?
Most characteristic cardiovascular defect seen in Rubella-
Identify the diagnosis based on the provided ECG image.
NEET-PG 2019 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 141: Which murmur increases on standing?
- A. HOCM (Correct Answer)
- B. MR
- C. MS
- D. VSD
Explanation: ***HOCM*** - Standing decreases **venous return** and **left ventricular volume**, which reduces the size of the LV outflow tract and thus exacerbates the obstruction in **hypertrophic obstructive cardiomyopathy (HOCM)**, making the murmur louder [1]. - This maneuver is a key diagnostic feature as reduced preload intensifies the dynamic obstruction. *MR* - **Mitral regurgitation (MR)** is typically a volume overload lesion, and standing (which reduces preload) generally causes the murmur to **decrease** in intensity due to less blood volume ejected back into the atrium [3]. - The murmur of MR is usually a holosystolic murmur radiating to the axilla [3]. *MS* - **Mitral stenosis (MS)** is a fixed obstruction to left ventricular filling. Changes in preload (like standing) do not significantly alter the gradient across the mitral valve or the intensity of the murmur [2]. - Its characteristic murmur is a **mid-diastolic rumble** with an opening snap [1]. *VSD* - A **ventricular septal defect (VSD)** murmur is caused by blood flowing from the high-pressure left ventricle to the low-pressure right ventricle. Standing, by reducing systemic vascular resistance, would typically cause the murmur to **decrease** in intensity as less blood shunts left-to-right. - The murmur is usually a **holosystolic murmur** best heard at the lower left sternal border.
Question 142: Most characteristic cardiovascular defect seen in Rubella-
- A. Patent ductus arteriosus (Correct Answer)
- B. Coarctation of the aorta
- C. Ventricular septal defect
- D. Pulmonary artery stenosis
Explanation: ***Patent ductus arteriosus*** - **Patent ductus arteriosus (PDA)** is the most characteristic cardiovascular defect associated with congenital rubella syndrome [1]. - The rubella virus can interfere with the normal closure of the **ductus arteriosus** during fetal development [1]. *Coarctation of the aorta* - **Coarctation of the aorta** is a narrowing of the aorta and is not typically linked to congenital rubella syndrome [1]. - It is often associated with syndromes like **Turner syndrome** or bicuspid aortic valve, which are not mentioned here [1]. *Ventricular septal defect* - **Ventricular septal defects (VSDs)** are common congenital heart defects, but they are not specifically characteristic of congenital rubella [1]. - VSDs are more frequently associated with conditions like **Down syndrome** or can occur in isolation [1]. *Pulmonary artery stenosis* - While **pulmonary artery stenosis** can occur as a congenital heart defect, it is less commonly the primary cardiovascular manifestation of congenital rubella syndrome. - **Peripheral pulmonary artery stenosis** can be seen in rubella, but PDA is the most characteristic overarching defect [1].
Question 143: Identify the diagnosis based on the provided ECG image.
- A. VT
- B. PSVT (Correct Answer)
- C. AT
- D. Ventricular fibrillation
Explanation: ***PSVT*** - The ECG shows a **narrow complex tachycardia** with a regular rhythm and a high heart rate, characteristic of **paroxysmal supraventricular tachycardia (PSVT)**. - P waves are often **buried within the QRS complex** or T waves, or may be retrograde, which can be seen as small deflections or changes in the baseline in some leads. *VT* - **Ventricular tachycardia** is characterized by a **wide QRS complex** (>0.12 seconds), which is not observed in this ECG. - While VT can be regular, the primary distinguishing feature is the QRS duration. *AT* - **Atrial tachycardia (AT)** is another form of supraventricular tachycardia, but it typically shows **distinct P waves** with an abnormal morphology, often separate from the T wave, which are not clearly visible or consistently distinct in this tracing. - While it can present with narrow complex tachycardia, the mechanism differs from re-entrant PSVT. *Ventricular fibrillation* - **Ventricular fibrillation** is characterized by **chaotic, irregular electrical activity** with no distinguishable P waves, QRS complexes, or T waves, representing disorganized ventricular depolarization. - The ECG in the image shows a consistent, regular rhythm with identifiable, albeit narrow, QRS complexes.
Obstetrics and Gynecology
1 questionsFemale with 41 wk gestation confirmed by radiological investigation, very sure of her LMP, no uterine contractions, no effacement and no dilatation. What should be done to induce labor?
NEET-PG 2019 - Obstetrics and Gynecology NEET-PG Practice Questions and MCQs
Question 141: Female with 41 wk gestation confirmed by radiological investigation, very sure of her LMP, no uterine contractions, no effacement and no dilatation. What should be done to induce labor?
- A. PGE1 tab (Correct Answer)
- B. PGE2 gel
- C. PGF2alpha
- D. Intracervical foley’s
Explanation: ***PGE1 tab*** - **Misoprostol (PGE1)** is an effective agent for **cervical ripening** and labor induction in cases of an unfavorable cervix (no effacement, no dilatation). - It is cost-effective, stable at room temperature, and widely used in resource-limited settings. - Can be administered orally or vaginally with good efficacy for cervical ripening at term. - In this post-term pregnancy with unfavorable cervix, pharmacological ripening is appropriate. *PGE2 gel* - **PGE2 (dinoprostone)** gel or cervical insert is also an effective option for cervical ripening. - Both PGE1 and PGE2 are acceptable first-line agents; the choice may depend on availability, cost, and institutional protocols. - PGE2 formulations are FDA-approved and widely used, though may be more expensive than misoprostol. *PGF2alpha* - **PGF2alpha (carboprost)** is primarily used for the **management of postpartum hemorrhage** due to its potent myometrial contracting effect. - It is **not indicated** for induction of labor at term as its strong uterine contractions can cause excessive uterine stimulation and fetal distress. *Intracervical foley's* - An **intracervical Foley catheter** is a mechanical method that causes cervical ripening through direct pressure and stimulation of local prostaglandin release. - It is an evidence-based alternative with lower risk of uterine hyperstimulation compared to pharmacological methods. - Both mechanical and pharmacological methods are acceptable first-line options for cervical ripening in post-term pregnancy with unfavorable cervix.
Ophthalmology
1 questionsWhich of the following statements about conjunctival lesions is NOT true?
NEET-PG 2019 - Ophthalmology NEET-PG Practice Questions and MCQs
Question 141: Which of the following statements about conjunctival lesions is NOT true?
- A. Arise from any part of conjunctiva
- B. Can cause Astigmatism
- C. Surgery is treatment of choice (Correct Answer)
- D. UV exposure is risk factor
Explanation: ***Surgery is treatment of choice*** - While surgery can be used to treat conjunctival lesions, it is not always the **treatment of choice**, especially for smaller, asymptomatic lesions like **pinguecula** which may only require observation and lubrication. - Many conjunctival lesions, such as uncomplicated **pterygium** or **pinguecula**, are managed conservatively unless they cause significant symptoms, vision impairment, or cosmetic concerns. *Arise from any part of conjunctiva* - **Conjunctival lesions** can indeed arise from various parts of the conjunctiva, including the palpebral, bulbar, and forniceal conjunctiva. - For example, **pterygium** typically arises from the bulbar conjunctiva, while **pinguecula** also originates in the bulbar conjunctiva, specifically in the interpalpebral fissure. *Can cause Astigmatism* - Larger **conjunctival lesions**, particularly a **pterygium** that encroaches onto the cornea, can induce or alter astigmatism. - The growth of the lesion can change the **curvature of the cornea**, leading to optical distortion and astigmatism. *UV exposure is risk factor* - **Ultraviolet (UV) light exposure** is a well-established risk factor for the development of many conjunctival lesions, including **pterygium** and **pinguecula**. - Chronic UV exposure leads to **elastotic degeneration** of the conjunctival collagen and is thought to play a key role in the pathogenesis of these growths.
Pharmacology
1 questionsWhat is the recommended dose of diphtheria antitoxin for adults?
NEET-PG 2019 - Pharmacology NEET-PG Practice Questions and MCQs
Question 141: What is the recommended dose of diphtheria antitoxin for adults?
- A. 1000 to 2000 IU
- B. 20000 to 50000 IU (Correct Answer)
- C. 10000 to 20000 IU
- D. None of the options
Explanation: ***20000 to 50000 IU*** - For adults with **diphtheria**, the recommended dose of **diphtheria antitoxin (DAT)** in the range of 20,000 to 50,000 IU is appropriate for **pharyngeal or laryngeal diphtheria** of moderate severity (typically disease present for 48-72 hours). - This dosage aims to neutralize the **diphtheria toxin** circulating in the bloodstream and prevent further tissue damage. - **Note:** More severe or extensive disease (>3 days duration or with bull neck) may require higher doses (80,000-120,000 IU). *1000 to 2000 IU* - This dosage is **too low** for therapeutic treatment of diphtheria in adults. - Such a low dose would be insufficient to neutralize the substantial amount of **toxin** produced during an active infection, regardless of disease severity. *10000 to 20000 IU* - This dose is **suboptimal** for most forms of diphtheria in adults. - Even for **mild cutaneous diphtheria**, doses typically start at 20,000 IU or higher. - For respiratory diphtheria, this range would be inadequate to effectively counteract the toxin. *None of the options* - This is incorrect because **20,000 to 50,000 IU** is a recognized and recommended range for diphtheria antitoxin in adult treatment of moderate pharyngeal/laryngeal disease. - Diphtheria antitoxin is a crucial and **specific treatment** for diphtheria, and evidence-based dosage ranges exist based on disease severity and location.
Physiology
1 questionsAchondroplasia shows which type of inheritance?
NEET-PG 2019 - Physiology NEET-PG Practice Questions and MCQs
Question 141: Achondroplasia shows which type of inheritance?
- A. X-linked dominant (XLD)
- B. Autosomal recessive inheritance
- C. Autosomal dominant inheritance (Correct Answer)
- D. X-linked recessive (XLR)
Explanation: ***Autosomal dominant inheritance*** - Achondroplasia is caused by a **mutation in the FGFR3 gene**, which is located on an **autosomal chromosome** (chromosome 4). - The disease manifests with only **one copy of the mutated gene**, hence it follows an autosomal dominant pattern. *X-linked dominant (XLD)* - X-linked dominant disorders are caused by mutations on the **X chromosome** and typically affect females more severely or frequently than males. - Achondroplasia does not show sex-linked inheritance patterns, as its causative gene is on an autosome. *Autosomal recessive inheritance* - Autosomal recessive disorders require **two copies of the mutated gene** (one from each parent) for the disease to manifest. - Achondroplasia can occur with only one copy of the mutated gene, distinguishing it from recessive inheritance. *X-linked recessive (XLR)* - X-linked recessive disorders primarily affect **males** and are carried by females, who are usually asymptomatic carriers. - The inheritance pattern of achondroplasia is independent of sex, ruling out X-linked recessive inheritance.
Surgery
1 questionsIdentify the surgical instrument based on its characteristics: a small, triangular blade used for precise incisions.
NEET-PG 2019 - Surgery NEET-PG Practice Questions and MCQs
Question 141: Identify the surgical instrument based on its characteristics: a small, triangular blade used for precise incisions.
- A. Blade no. 15
- B. Blade no. 10
- C. Blade no. 11 (Correct Answer)
- D. Blade no. 12
Explanation: ***Blade no. 11*** - This blade has a **triangular shape** with a strong, pointed tip, making it ideal for **stab incisions** and precise, short cuts. - Its design allows for sharp, accurate penetration, often used in procedures requiring **minimal tissue disruption**. *Blade no. 15* - This is a small, curved blade, primarily used for **fine, precise cuts** in superficial tissues. - Its small size and rounded belly make it suitable for tasks like excising skin lesions or making incisions in delicate areas, not for triangular stab incisions. *Blade no. 10* - The No. 10 blade has a **large, curved cutting edge** and is generally used for making large incisions in skin and muscle. - It is not designed for precise, triangular stab incisions, but rather for broader, sweeping cuts. *Blade no. 12* - This blade is **sickle-shaped** with the cutting edge on the inside curve, used primarily for mucogingival surgery or removing sutures. - Its unique shape allows it to get into tight spaces and cut from a different angle, but it does not have a triangular tip for precise stab incisions.