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In aging humans and rodents, inter-individual differences in cognitive function have been ascribed to variations in long-term glucocorticoid exposure. 11beta-Hydroxysteroid dehydrogenase type 1 (11beta-HSD1) regenerates the active glucocorticoid cortisol from circulating inert cortisone, thus amplifying intracellular glucocorticoid levels in some tissues. We show that 11beta-HSD1, but not 11beta-HSD2, mRNA is expressed in the human hippocampus, frontal cortex, and cerebellum. In two randomized, double-blind, placebo-controlled crossover studies, administration of the 11beta-HSD inhibitor carbenoxolone (100 mg three times per day) improved verbal fluency (P < 0.01) after 4 weeks in 10 healthy elderly men (aged 55-75 y) and improved verbal memory (P < 0.01) after 6 weeks in 12 patients with type 2 diabetes (52-70 y). Although carbenoxolone has been reported to enhance hepatic insulin sensitivity in short-term studies, there were no changes in glycemic control or serum lipid profile, nor was plasma cortisol altered. 11beta-HSD1 inhibition may be a new approach to prevent/ameliorate cognitive decline.  相似文献   
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The androgen content was measured in testes from 34 male and in ovaries from 30 female embryos that varied in age from less than 12 to approximately 20 weeks. The 5 alpha-reduced androgens dihydrotestosterone and 3 alpha-androstanediol were found in testes at a level of about a 30th of that of testosterone at all ages examined, whereas very little or no testosterone, androstenedione, or either of the 5 alpha-reduced androgens were detected in the ovaries. Whether dihydrotestosterone plays a role in the development of the testes is unknown.  相似文献   
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Insulin aspart (NovoLog, NovoRapid), a rapid-acting human insulin analog, provides more rapid absorption than regular human insulin after subcutaneous administration. In most randomized, nonblind clinical trials in patients with type 1 diabetes mellitus, insulin aspart administered immediately before meals resulted in significantly lower mean glycosylated hemoglobin (HbA1c) levels than regular human insulin (usually administered 30 minutes before a meal). Insulin aspart also significantly improved postprandial glycemic control compared with regular human insulin. The efficacy of insulin aspart was similar to that of insulin lispro when administered to patients with type 1 diabetes mellitus via continuous subcutaneous infusion in a randomized, nonblind trial. Preliminary data from randomized, nonblind trials suggest insulin aspart had a trend towards lower HbA1c levels compared with regular human insulin in patients with type 2,diabetes mellitus. Biphasic insulin aspart (30% soluble [rapid-acting] and 70% protamine-bound insulin aspart [BIAsp30]) [NovoLog Mix 70/30, NovoMix 30(2)] generally provided significantly better postprandial glucose control than a similar mixture of biphasic regular human insulin (BHI30) in a randomized, nonblind trial in patients with type 1 or 2 diabetes mellitus. However, the long-term efficacy of BIAsp30 was similar to that of BHI30 after 2 years in a randomized, nonblind trial in patients with type 2 diabetes mellitus. Patients with type 1 or 2 diabetes mellitus reported greater treatment satisfaction with insulin aspart or BIAsp30 than with regular human insulin or BHI30. The overall incidence of hypoglycemia with insulin aspart was lower than, or similar to, that of regular human insulin. Moreover, insulin aspart tended to be associated with a lower occurrence of nocturnal hypoglycemia and severe hypoglycemic events than regular human insulin. Conclusion: The standard preparation of insulin aspart has the potential to better mimic the physiological response to meals than regular human insulin. Insulin aspart when combined with a suitable basal insulin improved overall glycemic control and led to a similar or lower number of hypoglycemic episodes compared with a similar regular human insulin regimen. Insulin aspart was generally as effective and well tolerated as insulin lispro when administered by continuous subcutaneous infusion in a single comparative trial. The efficacy of biphasic insulin aspart has been documented in a small number of trials. Both insulin aspart and biphasic insulin aspart provide for flexible and convenient administration. Insulin aspart is now well established as an effective and convenient means of providing glycemic control which offers clinical and practical advantages over regular human insulin.  相似文献   
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Testicular torsion is a surgical emergency and requires prompt recognition and treatment. Health care personnel often forget this differential diagnosis in males who present with abdominal pain as their only complaint. There is a 4- to 6-hour window from the onset of symptoms to the surgical intervention to salvage the testes. It is imperative for health care personnel to consider testicular torsion in any male presenting with abdominal pain and to complete a genitourinary examination. The purpose of this case review is to highlight the importance of a genitourinary examination in recognizing testicular torsion.  相似文献   
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