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111.
Contact between the sexes in many species is known to produce hormonal changes in the male [increases in serum luteinizing hormone (LH) and/or testosterone] that can be interpreted as due to an intracerebral release of LH-releasing hormone (LHRH). In some circumstances, these hormonal changes appear to depend on an intact vomeronasal sensory system. Exogenous LHRH is also known to facilitate mating behavior in several species. We show here that LHRH delivered into the cerebral ventricles can restore some mating behavior lost when the vomeronasal organs are removed from sexually inexperienced male hamsters. The results are consistent with our working hypothesis that intracerebral LHRH release is an intermediate in the facilitation of mating behavior by vomeronasal sensory input. 相似文献
112.
J E Ryu G Howard T E Craven M G Bond A P Hagaman J R Crouse 《Stroke; a journal of cerebral circulation》1992,23(6):823-828
BACKGROUND AND PURPOSE: It has been suggested that a postprandial accumulation of triglyceride-rich lipoproteins promotes the development of atherosclerosis. This study was designed to test the hypothesis that postprandial lipemia is independently associated with intima-media thickening of the extracranial carotid arteries. METHODS: Forty-seven middle-aged, moderately hypercholesterolemic individuals were recruited for a 1-day study of the lipemic response to a standard high-fat test meal. The formula was fed at a dose of 65 g fat/m2 body surface area, after a 14-hour fast, and blood was obtained for triglyceride analysis hourly for 8 hours. A baseline lipid profile was obtained. Each subject underwent a carotid ultrasound examination. The extent of alimentary lipemia (peak triglyceride response) was correlated with the carotid artery wall thickness as measured by B-mode ultrasound. RESULTS: Univariate analyses indicated an inverse correlation between peak triglyceride response and high density lipoprotein cholesterol concentration and a direct correlation with male sex, baseline triglyceride concentration, background fat intake, and waist-to-hip ratio. Of these, the only variable that showed a univariate correlation with B-mode score was peak triglyceride response. Age and cigarette smoking were also correlated with B-mode score in univariate analyses. The correlation coefficient (r = 0.52) between peak triglyceride response to a fat-rich meal and B-mode score was significant (p less than 0.002) and remained so in multivariate analysis. Forward-selection stepwise regression resulted in the inclusion of only peak triglyceride response (p = 0.001) and smoking history (p = 0.005) as important predictors of carotid wall thickness in a linear model. CONCLUSIONS: The association between lipemic response and carotid wall thickness suggests that prolonged exposure of arterial wall cells to triglyceride-rich chylomicron remnants enhances the atherogenic process. 相似文献
113.
Lorraine V. Klerman Dr.P.H. Beth A. Baker M.S. George Howard Dr.P.H. 《The Journal of adolescent health》2003,32(6):452-455
This paper uses survival analysis to examine three large-scale, multi-site, randomized, controlled programs that attempted to prevent or delay second births to teenagers. Statistically significant differences in the hypothesized direction were found between the intervention and the control groups in the Elmira and Memphis Home Visitation sites. No statistically significant differences in the hypothesized direction were found in the Teen Parent Welfare Demonstration overall or in any of its three sites or in all New Chance sites combined. Delaying second pregnancies among teenagers requires intensive efforts. Survival analysis is a more accurate and useful way of presenting program results than simple analysis of the proportion of women with a second birth. 相似文献
114.
Werner's syndrome (WS) is often mistaken for scleroderma. We describe a patient with WS who presented with an enlarging, painful mass of the right knee that proved to be a juxtaarticular osteosarcoma of the distal femur. Recognition of WS and prompt investigation of any painful, enlarging masses to exclude sarcomatous degeneration will benefit these patients. 相似文献
115.
Background
Job satisfaction is important for nursing home staff and nursing home management, as it is associated with absenteeism, turnover, and quality of care. However, we know little about factors associated with job satisfaction and dissatisfaction for nursing home workers. 相似文献116.
The association between diabetes and hepatocellular carcinoma: a systematic review of epidemiologic evidence. 总被引:2,自引:0,他引:2
Hashem B El-Serag Howard Hampel Fariba Javadi 《Clinical gastroenterology and hepatology》2006,4(3):369-380
BACKGROUND & AIMS: We conducted a systematic review and a meta-analysis to estimate the magnitude and determinants of association between diabetes and hepatocellular carcinoma (HCC). METHODS: MEDLINE searches were conducted for published full studies (between January 1966 and February 2005) that provided risk estimates and met criteria concerning the definition of exposure and outcomes. Two investigators independently performed standardized search and data abstraction. Unadjusted and adjusted odds ratios for individual outcomes were obtained or calculated for each study and were synthesized using a random-effects model. RESULTS: A total of 26 studies met our inclusion and exclusion criteria. Among 13 case-control studies, diabetes was associated significantly with HCC in 9 studies (pooled odds ratio, 2.5; 95% confidence interval, 1.8-3.5). Among 13 cohort studies, diabetes was associated significantly with HCC in 7 studies (pooled risk ratio, 2.5; 95% confidence interval, 1.9-3.2). The results were relatively consistent in different populations, different geographic locations, and a variety of control groups. The significant association between HCC and diabetes was independent of alcohol use or viral hepatitis in the 10 studies that examined these factors. Few studies adjusted for diet and obesity. CONCLUSIONS: Diabetes is associated with an increased risk for HCC. However, more research is required to examine issues related to the duration and treatment of diabetes, and confounding by diet and obesity. 相似文献
117.
118.
Recent work on such apparently disparate fields as T-cell receptor peptide-induced regulation, superantigens, antigen-induced tolerance, models of peripheral tolerance, apoptosis, and T-cell receptor antagonists demonstrates a similarity in immune response from a regulatory perspective. In many systems, a ‘tolerance’ pathway is observed, characterized broadly as an initial disturbance in the immune system, with a resulting predominance of effector cells, followed by a homeostatic response (often requiring CD8+ cells) which leads the effector population into T-cell receptor downregulation, T-cell inactivation, anergy and, often, eventual apoptotic death. In the regulated immune response, mixed populations of anergized and apoptosing T cells can be found. In some cases, anergy appears to lead to death while, in other instances, cells revert to a functional state. This review focuses on recent papers examining each of these topics in an attempt to obtain a preliminary, integrated picture of immune regulation in autoimmune diseases. 相似文献
119.
Jeffrey S. Berns Howard A. Pearson Karen M. Gaudio Bruce McDonald Leonard Krassner Frederic Anderson Dennis Durante Norman J. Siegel 《Pediatric nephrology (Berlin, Germany)》1988,2(2):244-246
Children with the idiopathic nephrotic syndrome (NS) are known to be susceptible to bacterial infections. A recent report suggested that splenic hypofunction may be responsible for this immunological defect. We assessed splenic function by counting the circulating pocked red blood cells (PkRBCs) using interference phase contrast microscopy. PkRBCs are removed by the spleen, so that normal eusplenic individuals have less than 2% PkRBCs while asplenics have 15%–30%. Intermediate values are seen in hyposplenism. Thirty-three measurements of PkRBCs were made in 19 children with NS (mean age 7.5±0.8 years). PkRBCs were normal in all children tested (range 0–0.8%), including two patients with bacterial peritonitis associated with relapse. Thus we were unable to find evidence of hyposplenism in children with NS. 相似文献
120.