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1.
The normal function of the hypothalamic-pituitary-adrenal (HPA) axis, and resultant glucocorticoid (GC) secretion, is essential for human health. Disruption of GC regulation is associated with pathologic, psychological, and physiological disease states such as depression, post-traumatic stress disorder, hypertension, diabetes, and osteopenia, among others. As such, understanding the mechanisms by which HPA output is tightly regulated in its responses to environmental stressors and circadian cues has been an active area of investigation for decades. Over the last 20 years, however, advances in gene targeting and genome modification in rodent models have allowed the detailed dissection of roles for key molecular mediators and brain regions responsible for this control in vivo to emerge. Here, we summarize work done to elucidate the function of critical neuropeptide systems, GC-signaling targets, and inflammation-associated pathways in HPA axis regulation and behavior, and highlight areas for future investigation.  相似文献   
2.
Advances in science have increased the knowledge of how cells die in the body (apoptosis). A basic understanding of this process can improve nurses' ability to review new scientific literature and enable them to provide safer bedside care.  相似文献   
3.
4.
ATP as an Osteoclast Regulator?   总被引:1,自引:1,他引:0  
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5.
Silane-coated silica particle solutions (ISolate(TM) and PureSperm)TM)) and iodixanol (OptiPrep(TM)) were compared to polyvinylpyrrolidone (PVP)-coated silica particles (Percoll(TM)) in their efficacy to recover spermatozoa by gradient centrifugation for use in assisted reproductive procedures. Efficacy was assessed in terms of percentages of sperm recovery, sperm vitality and motility, normal sperm morphology and normal sperm chromatin condensation. No significant difference was found in the recovery of spermatozoa for men with both normal sperm counts and oligozoospermia, between PVP-coated and silane-coated particle solutions. Iodixanol had significantly lower sperm recovery compared to the other products. Sperm vitality, progressive motility, normal morphology and normal chromatin condensation did not differ significantly between any of the sperm isolation products.   相似文献   
6.
BackgroundSeveral variables are known to correlate with the successful completion of short-stay total hip arthroplasty (THA) protocols. The role of psychological factors remains unclear. We investigated the interaction between patient-reported measures of psychological fitness and successful completion of a short-stay THA protocol.MethodsWe performed a prospective cohort study of patients undergoing elective anterior total hip arthroplasty enrolled in a short-stay protocol (success defined as LOS ≤1 midnight versus failed, LOS >1 midnight). Psychological fitness was measured using the Patient-Reported Outcomes Measurement Information System (PROMIS) domains for self-efficacy, depression, anxiety, emotional support, and the ability to participate in social roles. PROMIS scores, patient demographics, and surgical factors were assessed for a relationship with failure to complete short-stay protocol.ResultsPatients that failed to complete the short-stay protocol had higher mean pre-operative PROMIS depression scores (50.8 vs 47.1, P = .025) and anxiety scores (53.6 vs 49.2, P = .008) and higher postoperative PROMIS depression (48.19 vs 43.49, P = .003) and anxiety scores (51.7 vs 47.1, P = .01). Demographic and surgical variables did not correlate with the successful completion of the short-stay protocol. That seventy-six percent of the patients did not adhere to the short-stay protocol was due to the inability to complete a physical therapy standardized safety assessment.ConclusionHigher levels of preoperative and postoperative anxiety and depression in otherwise psychologically healthy patients, is associated with an increased risk of failure to complete a short-stay protocol following THA. Targeted interventions are needed to facilitate rapid recovery in patients with psychological barriers to early mobilization.  相似文献   
7.
Every year, analysts in the Health Care Financing Administration present figures on what our Nation spends for health. As the result of a comprehensive re-examination of the definitions, concepts, methods, and data sources used to prepare those figures, this year's report contains new estimates of national health expenditures for calendar years 1960 through 1988. Significant changes have been made to estimates of spending for professional services and to estimates of what consumers pay out of pocket for health care. In the first article, trends in use of and expenditure for various types of goods and services are discussed, as well as trends in the sources of funds used to finance health care. In a companion article, the benchmark process is described in more detail, as are the data sources and methods used to prepare annual estimates of health expenditures.  相似文献   
8.
BACKGROUND: The epidemiologic observation that physical activity reduces the risk for hypertension has only been made for white men who self-reported hypertension. This study examined physical activity and clinically determined incident hypertension in black and white men and women of the Atherosclerosis Risk in Communities (ARIC) Study. METHODS: ARIC is a population-based prospective study with four U.S. clinic centers. The present analyses included 7,459 black and white adults 45-65 years of age. Hypertension (systolic/diastolic blood pressure >/= 140/90 mm Hg) was defined by blood pressure measured by a random-zero device or medication use. Physical activity was assessed with the Baecke questionnaire. RESULTS: After adjustment for age, baseline blood pressure, ARIC center, education, body mass index, waist-hip ratio, parental history of hypertension, cigarette smoking, alcohol consumption, and diet, white men in the highest quartile of leisure activity (primarily cycling and walking) had a 34% lower odds of developing hypertension over 6 years compared to the least active (OR = 0.66, 95% CI = 0.47-0.94; P for quartile trend = 0.01). Baseline activity was not associated with incident hypertension in white women or blacks. CONCLUSIONS: Leisure-time physical activity reduces the odds of hypertension in middle-aged white men. Additional studies in women and blacks are needed.  相似文献   
9.
Objectives: The purpose of this study was to examine gender and ethnic differences in survival of persons receiving treatment for HIV infection to determine if differences existed, and if they did, to assess the possibility of explaining these differences by examining other factors, such as age, disease severity when beginning treatment, alcohol, illicit drugs, tobacco, educational level, living arrangements, antiretroviral treatment, PCP prophylaxis, sexually transmitted diseases, mode of transmission and opportunistic infections.

Design: A retrospective cohort study of all clients receiving treatment at an HIV only clinic from its opening in early 1988 until the end of May 1993. Statistical methods used to examine the data included incidence density ratios, Kaplan‐Meier survival curves, Breslow (generalized Wilcoxon) tests of equality of survival curves and Cox proportional hazards models both with and without time dependent covariates.

Results: In the cohort (37% African American, 7% Hispanic American and 25% female), 220 deaths occurred during 1223 person years of follow‐up. Compared to European American males, the following incidence density ratios were observed: European American females: 0.50, Hispanic American females: 0.70, Hispanic American males: 0.96, African American females: 1.28 and African American males: 2.38. The differences were noted above for gender/ethnicity groups were significant at the p < 0.0001 level. After adjusting for disease stage (as measured by laboratory testing of CD4 positive T‐lymphocytes), educational level, and age, no differences in survival by gender or ethnicity remained. Disease stage and educational level had the greatest prognostic significance.

Conclusions: European Americans entered treatment at a much earlier disease stage (as measured by CD4 positive T‐lymphocyte counts) and had higher educational levels (a surrogate for socioeconomic status) than African Americans. These factors may explain the longer survival in European Americans as compared to African Americans in this cohort.  相似文献   

10.
With limited training budgets and an increasing range of training opportunities available, provider units will need to have effective training strategies. The Grantham model, described by Kevin Teasdale and colleagues, offers a clear and practical approach.  相似文献   
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