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Dopamine signaling has been implicated in the control of food intake and body weight. In particular, dopamine is important in the control of meal size and number and is thought to mediate the response to metabolic deprivation states. In the present experiments, the authors assessed the role of the dopamine-3 receptor (D3R) in the feeding responses to 2-deoxy-D-glucose, mercaptoacetate, and peripheral insulin. All 3 compounds increased food intake in wild-type mice, but the hyperphagic responses were blunted in D3R-/- mice. In other experiments, D3R-/- mice were hyperresponsive to the administration of amylin and leptin relative to wild-type mice. These results support the hypothesis that D3Rs chronically inhibit the effects of adiposity hormones, thereby contributing to a net anabolic state.  相似文献   
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During the training phase, 96 subjects were given one of four types of relaxation instructions (single instructions, repeated instructions, relaxation training, no instructions) and in addition either did or did not receive frontal EMG biofeedback training. Results indicated that each of the instructions and biofeedback procedures were equally effective in reducing frontal EMG, but that none of these procedures had any effect on subjective anxiety or autonomic indices of arousal (pulse rate, skin temperature, and finger pulse volume). During the generalization/stress phase, subjects were threatened with electric shock and were told to apply the relaxation techniques they learned during the training phase even though no additional instructions and/ or biofeedback training would be provided. To assess the effectiveness of the shock manipulation, a no-threat control group was included. Results indicated that: a) the shock manipulation was effective in increasing arousal, b) previous instructions and/or biofeedback were equally effective in reducing frontal EMG levels, but that c) only relaxation training was consistently effective in reducing subjective and autonomic indices of arousal. These findings: a) suggest that in stressful situations, relaxation training may be more effective than either EMG biofeedback or simple relaxation instructions in producing a general relaxation effect as opposed to a specific EMG effect; and b) indicate the importance of assessing the effectiveness of relaxation procedures during stressful situations during which subjects’ levels of arousal are elevated above resting baseline levels.  相似文献   
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目的:考察大、中学生对文化维度的知觉的情况和发展趋势。方法:用Trandis编制的个人主义-集体主义量表(Individualism-Collectivism Scale)对1760名大、中学生进行测量。结果:大、中学生对文化维度的知觉存在年龄效应;随着年龄增加,对集体主义维度的知觉从42.05%下降到27.40%,而对个人主义维度的知觉从5.01%上升到18.58%;水平维度的知觉从47.06%下降到40.71%;垂直维度的知觉从4.14%上升到6.19%。结论:大、中学生对文化维度的知觉的差异主要表现在个人主义和集体主义的维度,水平维度和垂直维度有轻微的波动。  相似文献   
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Phenylketonuria (PKU) is a genetic disorder secondary to a deficiency of hepatic phenyalanine hydroxylase (PAH). Several mutations in thePAH gene have recently been reported, and linkage disequilibrium was observed between RFLP haplotypes and specific mutations. A new molecular lesion has been identified in exon 7 of thePAH gene in a Hungarian PKU patient by direct sequencing of PCR-amplified DNA. The C-to-T transition causes the substitution of Arg243 to a termination codon, and the mutant allele is associated with haplotype 4 of thePAH gene. The mutation is present in two of nine mutant haplotype 4 alleles among Eastern Europeans and is not present among Western Europeans and Asians. The rarity of this mutant allele and its restricted geographic distribution suggest that the mutational event occurred recently on a normal haplotype 4 background in Eastern Europe.  相似文献   
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ContextMolecular biomarkers aim to address the established limitations of clinicopathologic factors to accurately risk stratify patients with prostate cancer (PCa). Questions remain as to whether sufficient evidence supports adoption of these biomarkers for clinical use.ObjectiveTo perform a systematic review of the available evidence supporting the clinical utility of the Decipher genomic classifier (GC).Evidence acquisitionThe review was performed as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines by searching PubMed and conference abstracts from January 2010 to June 2020. Evidence was then graded using the criteria of Simon et al (Simon RM, Paik S, Hayes DF. Use of archived specimens in evaluation of prognostic and predictive biomarkers. J Natl Cancer Inst 2009;101:1446–52) and American Urology Association (AUA) criteria.Evidence synthesisIn total, 42 studies and 30 407 patients were included. GC performance data were available for localized, postprostatectomy, nonmetastatic castration-resistant, and metastatic hormone-sensitive PCa as part of retrospective studies (n = 12 141), prospective registries (n = 17 053), and prospective and post hoc randomized trial analyses (n = 1213). In 32 studies (n = 12 600), the GC was independently prognostic for all study endpoints (adverse pathology, biochemical failure, metastasis, and cancer-specific and overall survival) on multivariable analysis and improved the discrimination over standard of care in 24 studies (n = 8543). GC use changed the management in active surveillance (number needed to test [NNT] = 9) and postprostatectomy (NNT = 1.5–4) settings in five studies (n = 4331). Evidence strength was levels 1 and 2 by the Simon criteria for all disease states other than high-risk PCa, and grades A and B by AUA criteria depending on disease state.ConclusionsConsistent data are now present from diverse levels of evidence, which when viewed together, have demonstrated clinical utility of the GC in PCa. The utility of the GC is strongest for intermediate-risk PCa and postprostatectomy decision-making.Patient summaryIn this paper, we review the evidence of the Decipher genomic classification tool for men with prostate cancer. We found consistent evidence that the test helps identify which cancers are more or less aggressive, which in turn aids in personalized treatment decision-making.  相似文献   
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The last line in column one on page 2274 was published incorrectly.It should have read:...TGF-2 but not with turkey anti-TGF-1(data not shown).  相似文献   
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