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Type 2 deiodinase (D2) converts the prohormone thyroxine (T4) to the metabolically active molecule 3,5,3′-triiodothyronine (T3), but its global inactivation unexpectedly lowers the respiratory exchange rate (respiratory quotient [RQ]) and decreases food intake. Here we used FloxD2 mice to generate systemically euthyroid fat-specific (FAT), astrocyte-specific (ASTRO), or skeletal-muscle-specific (SKM) D2 knockout (D2KO) mice that were monitored continuously. The ASTRO-D2KO mice also exhibited lower diurnal RQ and greater contribution of fatty acid oxidation to energy expenditure, but no differences in food intake were observed. In contrast, the FAT-D2KO mouse exhibited sustained (24 h) increase in RQ values, increased food intake, tolerance to glucose, and sensitivity to insulin, all supporting greater contribution of carbohydrate oxidation to energy expenditure. Furthermore, FAT-D2KO animals that were kept on a high-fat diet for 8 weeks gained more body weight and fat, indicating impaired brown adipose tissue (BAT) thermogenesis and/or inability to oxidize the fat excess. Acclimatization of FAT-D2KO mice at thermoneutrality dissipated both features of this phenotype. Muscle D2 does not seem to play a significant metabolic role given that SKM-D2KO animals exhibited no phenotype. The present findings are unique in that they were obtained in systemically euthyroid animals, revealing that brain D2 plays a dominant albeit indirect role in fatty acid oxidation via its sympathetic control of BAT activity. D2-generated T3 in BAT accelerates fatty acid oxidation and protects against diet-induced obesity.  相似文献   
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Self-testing has untapped potential as a strategy to improve access to HIV testing and to increase testing frequency. User acceptability of self-administered oral swab HIV tests is consistently high in both hypothetical and actual-use studies. We explored preferences for oral versus fingerprick HIV self-tests among men who have sex with men with a high risk profile. Participants indicated greater likelihood of using an oral swab over a blood-based test, notwithstanding lower price or quicker results from the latter. However, the likelihood of using an HIV fingerprick test substantially increased if it also offered information on other sexually transmitted infections.  相似文献   
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ObjectiveTo report a comparative clinical and histopathological study on oliguric and non-oliguric acute renal failure (ARF) in malaria.Method311 consecutive cases of malaria out of which 74 (23.79%) had ARF as per WHO criteria were conducted. Mean age was 32.58 (range 15–60 years) and male: female was 2:1.ResultMost of the cases developed ARF within 10 d of onset. 18 cases (11 falciparum, 2 mixed, 5 vivax) presented with oliguric and 56 (41 falciparum, 6 mixed, 9 vivax) with non-oliguric renal failure. Associated major manifestations were jaundice (75.68%), cerebral malaria (41.89%), bleeding manifestations (32.43%), severe anemia (27.03%), hypotension (25.68%), multi-organ failure (18.92%), severe thrombocytopenia (12.16%), and ARDS (8.11%). Kidney biopsy (n=20) showed acute tubular necrosis (n=7), Mesangioproliferative glomerulonephritis (n=4) or both (n=9). Hemodialysis was done in 8 cases of oliguric renal failure out of which 4 survived (average no. of session 2.9).ConclusionMost of the cases recovered within 3 weeks. Total mortality was 28.38% (n=21) and mortality was more in oliguric renal failure (72.22%) as compare to non-oliguric renal failure (14.29%).  相似文献   
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Atherosclerotic subclavian artery disease is detected in about 5% of patients referred for coronary artery bypass (CABG) surgery. The internal mammary artery, a branch of the subclavian artery, is the most frequently utilized graft to restore coronary circulation because of its longevity. Stenosis or occlusion of the subclavian artery can cause retrograde blood flow in the ipsilateral internal mammary artery, known as “steal,” compromising coronary circulation supplied by the graft. Steal may be asymptomatic or may result in symptoms of myocardial ischemia. Symptomatic subclavian artery stenosis post bypass is referred to as coronary subclavian steal syndrome post‐CABG. The incidence is not well defined, and the benefits of screening patients referred for CABG are not known. Despite the various modalities available to detect subclavian artery stenosis, current guidelines fail to provide guidance about screening high‐risk patients for this entity. Detection of subclavian artery disease prior to CABG can reduce complications posed by post‐mammary artery graft cardiac ischemia. This review discusses the utility of preoperative subclavian artery screening prior to CABG.  相似文献   
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The incidence of lung cancer is rising dramatically and it is now the commonest cause of mortality and morbidity not only in the industrialised countries, but in developing nations like India as well. Tobacco smoking has consistently been demonstrated to be an important aetiological factor, though lung cancer occurs in non-smokers also. In spite of great advances in radiological and molecular diagnostic techniques, the ideal screening marker for early detection of lung cancer has still not been found. Histological diagnosis and staging is essential for selecting the mode of therapy in patients with lung cancer. Stages I and II are amenable to surgery. However, advanced stage III and IV need an individualised combination of surgery, chemotherapy and radiotherapy. With a better understanding of the cellular mechanisms operating in carcinogenesis, newer target specific modalities are being developed and tested in order to stem this disease, which threatens to assume epidemic proportions.  相似文献   
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