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The central melanocortin system plays a critical role in energy homeostasis. It is well established that melanocortin-containing neurons are nutritionally regulated and that genetic alterations in the melanocortin system produce profound effects on food intake, energy expenditure, and body weight. Within the brain, melanocortin-producing neurons originate in the arcuate nucleus of the hypothalamus (ARC) and the nucleus of the solitary tract (NTS) in the brainstem and project to various nuclei modulating energy balance. A large body of pharmacological and genetic evidence implicates the central melanocortin 4 receptors (MC4Rs) in the effects of melanocortin peptides on ingestive behaviour, energy expenditure, and body weight. Preclinical studies with endogenous and synthetic melanocortin ligands demonstrate that they produce potent effects on food intake and energy expenditure. Clinical studies thus far have been somewhat less successful and have been hampered by the induction of side effects, which present obstacles to the development of successful therapeutic agents. However, various promising strategies are being pursued to overcome these limitations, including the synthesis of more selective and potent melanocortin analogs.  相似文献   
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The house fly, Musca domestica L., is one of the major pests in dairy operations that has developed resistance to a number of insecticides with different modes of action. Adult house fly populations from six dairies in Punjab, Pakistan were evaluated for resistance to insecticides with novel modes of action (abamectin, emamectin benzoate, fipronil, imidacloprid, indoxacarb, and spinosad). Significant levels of resistance to most of the insecticides tested were observed in the present study. For avermectins at LC50 level, the resistance ratios were in the range of 38.40 to 94.44-fold for abamectin and 13.16 to 36.30-fold for emamectin benzoate. Fipronil LC50 resistance ratios exceeded 10-fold in three house fly populations, while all the populations had >10-fold resistance ratios for imidacloprid. Indoxacarb and spinosad had the lowest resistance ratios that ranged from 3.02 to 7.12-fold for indoxacarb and 2.91 to 9.0-fold for spinosad. As the resistance to fipronil, indoxacarb, and spinosad are emerging, therefore these chemicals should be used cautiously in management programs to retain the efficacy for longer times.  相似文献   
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Child & Youth Care Forum - Community attachments are thought to promote adolescents’ engagement in public health behaviors. To date, past research has exclusively examined the social...  相似文献   
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Pharmaceutical Chemistry Journal - Di- and triorganotin(IV) derivatives of 3-(4-nitrophenyl)-2-methylacrylic acid (HL), i.e., [n-Bu2SnL2] (1), [Me2SnL2] (2), [n-Bu3SnL]n (3) [Me3SnL]n (4) and...  相似文献   
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Pemphigus and pemphigus-like reactions can be triggered by a variety of medications including topical therapies, such as imiquimod. While the association between imiquimod and pemphigus-like reactions has been reported in adults, this is the first report of a generalized reaction beyond the site of imiquimod application in a child. The mechanism by which this occurs may be through a unique pathway, separate from the classic antibody-mediated pathway. Our patient had a full recovery without recurrence after cessation of the inciting drug.  相似文献   
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OBJECTIVE: The purpose of this study was to compare maternal, neonatal, and second stage of labor characteristics in shoulder dystocia deliveries that result in permanent brachial plexus injury with shoulder dystocia deliveries that result in no injury. STUDY DESIGN: Our cases were culled from a database of deliveries that resulted in permanent brachial plexus injuries and matched to control cases that were taken from a database of consecutive shoulder dystocia deliveries from one hospital. Deliveries that resulted in injury were excluded from the control cases; those cases with no recorded shoulder dystocia were excluded from the cases. Matching was for birth weight (+/-250 g), parity, and diabetic status. Rates of precipitous and prolonged second stage, operative delivery, neonatal depression, and average number of shoulder dystocia maneuvers used were compared between the two groups with chi(2) test, Fisher exact test, and the Student t test; a probability value of <.05 was considered significant. RESULTS: There were 80 matched patients, of which 26 patients were nulliparous and 11 patients were diabetic. Mothers of the uninjured group were younger than those of the injured group (23.7+/-6.2 years vs 27.4+/-5.1 years, P<.001). The injured group had a significantly higher rate of 5-minute Apgar scores of <7 (13.9% vs 3.8%, P=.04). Differences in maternal weight, body mass index, height, race, gestational age, average number of maneuvers, head-to-body delivery interval, operative delivery rate, prolonged second stage rate, precipitous second stage rate, and sex were not significant between groups. The rates of precipitous second stage for both groups (28.0% injured and 35.0% uninjured) were more than triple the rates of prolonged second stage (9.5% injured and 11.3% uninjured). CONCLUSION: No characteristic of second-stage of labor predicts permanent brachial plexus injury. Precipitous second stage is the most prevalent labor abnormality that is associated with shoulder dystocia.  相似文献   
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