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101.
We hypothesized that menstrual disturbances in female athletes arise from opioid-induced abnormalities in gonadotropin and/or prolactin (PRL) secretion. To investigate this hypothesis, we measured luteinizing hormone, follicle-stimulating hormone, and PRL levels in eumenorrheic and amenorrheic athletes during thyrotropin-releasing hormone and gonadotropin-releasing hormone tests at baseline, after naloxone infusions, after exercise to exhaustion, and after similar exercise during naloxone infusions. Contrary to our hypothesis, amenorrheic runners did not have significant alterations in basal, postexercise, or stimulated hormone levels compared with eumenorrheic runners. In addition, opioid blockade by naloxone did not enhance gonadotropin release by amenorrheic athletes. 相似文献
102.
F Hatton MH Bouvier-Colle A Barois MC Imbert A Leroyer S Bouvier E Jougla 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(12):1366-1371
An enquiry into sudden infant death syndrome (SIDS) in 1987 furnished us with detailed epidemiological data for 281 cases that underwent a thorough post-mortem examination. This analysis uses these data to evaluate the role the autopsy plays in explaining sudden death. The cases were classified into three diagnostic groups: explained causes of death (group 1), unexplained deaths with anomalies (group 2), and no anomaly (group 3). These 281 cases show the three essential features that characterize SIDS: over-representation of males, increased deaths during the second and third months of life, and increased deaths during winter. The autopsy examination revealed that many of these deaths had a medical explanation. Almost half were assigned to group 1. At the time of autopsy, no precise pathology could be diagnosed for 147 deaths; of these, 140 showed histological anomalies. There were only seven sudden deaths for which no abnormal sign was evident at the autopsy. These results are compared with those of similar studies and discussed in connection with three factors: the initial selection of cases, the nature and degree of the investigations, and the possible interpretations of the symptoms uncovered. 相似文献
103.
Baracos VE Samuels SE Adegoke OA 《Current opinion in clinical nutrition and metabolic care》2000,3(3):183-189
Studies on regulation of protein turnover in skeletal muscle have revealed the important contributions of protein synthesis and catabolism to tissue protein balance, and have identified a host of specific anabolic and catabolic stimuli and biochemical mechanisms that regulate these processes. This knowledge is critical to current efforts designed to promote anabolism and limit atrophy. Of the tissues with a potentially large contribution to whole-body amino acid metabolism, protein turnover of the intestine stands out as being poorly understood. The intestine is subject to complexities in regulation of its metabolism that are not apparent for other tissues. The study of intestinal protein turnover also entails some important technical challenges. We recently developed an in-situ experimental system for study of intestinal mucosal protein synthesis with the following unique features: multiple observations within an animal; controlled delivery of nutritional stimuli to the apical side, basolateral side, or both; and luminal delivery of tracer in a flooding dose for determination of protein synthesis. We have begun to use the system to test the specific roles of individual luminal nutrients in regulation of mucosal protein synthesis. We have also used protease gene expression as an index of potential regulation of catabolic pathways. 相似文献
104.
105.
Rupture of a coronary artery aneurysm may result in a contained hematoma and an intramyocardial mass. We present a case of a contained coronary artery aneurysm rupture presenting as a mass in the right ventricle. The mass was suspected in a preoperative transthoracic echocardiogram and identified at the time of elective coronary artery bypass surgery. We discuss the pathophysiology, clinical presentation, diagnostic features, and management of this uncommon clinical presentation. 相似文献
106.
Serum dioxin concentrations and menstrual cycle characteristics 总被引:5,自引:0,他引:5
Eskenazi B Warner M Mocarelli P Samuels S Needham LL Patterson DG Lippman S Vercellini P Gerthoux PM Brambilla P Olive D 《American journal of epidemiology》2002,156(4):383-392
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a widespread industrial environmental contaminant. Animal studies suggest that TCDD exposure alters the estrus cycle. Twenty years after a 1976 industrial explosion in Seveso, Italy, the authors interviewed female residents to determine whether there was an association between TCDD exposure and current menstrual cycle characteristics. The authors analyzed serum samples collected soon after the explosion to quantify individual TCDD levels. Among women who were premenarcheal at the time of the explosion, a 10-fold increase in serum TCDD level was associated with a lengthening of the menstrual cycle by 0.93 days (95% confidence interval (CI): -0.01, 1.86) and a reduction in the odds of scanty menstrual flow (adjusted odds ratio = 0.33, 95% CI: 0.10, 1.06). However, among women who were postmenarcheal at the time of the explosion, TCDD was not associated with menstrual cycle length (adjusted beta = -0.03 days, 95% CI: -0.61, 0.54) or scantiness of flow (adjusted odds ratio = 1.36, 95% CI: 0.70, 2.64). In both menarche groups, TCDD levels were associated with decreased odds of having irregular cycles (adjusted odds ratio = 0.46, 95% CI: 0.23, 0.95) but were not related to days of flow (adjusted beta = 0.16 days, 95% CI: -0.08, 0.41). These results are consistent with effects of TCDD on ovarian function noted in some animal species and with greater sensitivity to TCDD during development. 相似文献
107.
108.
BACKGROUND: Agriculture is a hazardous industry associated with many occupational injuries and illnesses. We describe California farmers' self-reported exposure to five agricultural hazards and their use of protective equipment. METHODS: A telephone survey of 1,947 California farmers recorded information on occupational exposure, health outcomes and use of protective equipment to lessen risk from exposure to dust, sun, noise, pesticides and tractors. RESULTS: Over 93% of respondents reported using personal protection around pesticides; however, fewer than 1/3 used consistent protection against other hazards. Younger age and male sex were associated with better use of protection from dust, noise, pesticide and tractors, but negatively associated with sun protection. There was no consistent relationship of protective behaviors with cigarette smoking, living on the farm, marital status, or time in non-administrative farmwork. Risk perception was strongly associated with behavior; farmers concerned about specific health problems were much more likely to use protective equipment. CONCLUSIONS: Some farmer characteristics are associated with more safe behaviors, but efforts to encourage protective behaviors on farms should be broadly based in view of a lack of a single risk-taking profile among California farmers. 相似文献
109.
Cancer statistics for African Americans 总被引:15,自引:0,他引:15
Ghafoor A Jemal A Cokkinides V Cardinez C Murray T Samuels A Thun MJ 《CA: a cancer journal for clinicians》2002,52(6):326-341
The American Cancer Society provides estimates on the number of new cancer cases and deaths, and compiles health statistics on African Americans in a biennial publication, Cancer Facts and Figures for African Americans. The compiled statistics include cancer incidence, mortality, survival, and lifestyle behaviors using the most recent data on incidence and survival from the National Cancer Institute's (NCI) Surveillance, Epidemiology, and End Results (SEER) program, mortality data from the National Center for Health Statistics (NCHS), and behavioral information from the Behavior Risk Factor Surveillance System (BRFSS), Youth Risk Behavior Surveillance System (YRBSS), and National Health Interview Survey (NHIS). It is estimated that 132,700 new cases of cancer and 63,100 deaths will occur among African Americans in the year 2003. Although African Americans have experienced higher incidence and mortality rates of cancer than whites for many years, incidence rates have declined by 2.7 percent per year in African-American males since 1992, while stabilizing in African-American females. During the same period, death rates declined by 2.1 percent and 0.4 percent per year among African-American males and females, respectively. The decrease in both incidence and death rates from cancer among African-American males was the largest of any racial or ethnic group. Nonetheless, African Americans still carry the highest cancer burden among US racial and ethnic groups. Most cancers detectable by screening are diagnosed at a later stage and survival rates are lower within each stage of disease in African Americans than in whites. The extent to which these disparities reflect unequal access to health care versus other factors is an active area of research. 相似文献
110.