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41.
Regular physical activity has both short- and long-term health benefits in adults. No study has investigated childhood determinants of adult physical activity patterns, however. In a nonconcurrent prospective study, the physical activity levels of 453 young men, 23 to 25 years of age, were compared with their physical fitness test scores as children (10 to 11 years of age and 15 to 18 years of age). The physically active adults had significantly better childhood physical fitness test scores than did the inactive adults. In 224 children, 2 years of fitness test results were available. The risk of physical inactivity in young adulthood was linearly related to the number of low scores on the 548.6-m (600-yd) run and sit-ups tests as children (P less than .001). In stepwise multivariate discriminant analysis, the childhood 548.6-m run score was the best discriminator between currently physically active and inactive adults. Reported parental encouragement of exercise, level of education, participation in organized sports after high school, and reported spousal encouragement of exercise also contributed significantly to the discriminant function. These results demonstrate that physical fitness testing in boys facilitates the identification of those at increased risk of becoming physically inactive young adults.  相似文献   
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Nine centers collaborated to determine the rate of urinary tract infection in infants with unexplained fever, to determine whether the rate is higher in febrile infants than in asymptomatic infants, and whether the yield justifies urine cultures in febrile infants. Urine cultures were done in 501 infants 0 to 2 years of age. The rate of confirmed urinary tract infections in the 193 febrile infants was 4.1%. All infections were in girls, with a rate of 7.4%. The rate of confirmed urinary tract infections in the 312 asymptomatic infants was 0.3%; again, all infections were in girls, with a rate of 0.7%. The rate in febrile girls was significantly higher than the rate in asymptomatic girls (P less than 0.01). The data support the advisability of culturing the urine of infant girls with unexplained fever.  相似文献   
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Health-related quality of life in schizophrenia can be assessed by direct patient response or by a rating based on a structured interview. This study compares both types of instruments using a series of five standards: (1) sensitivity to change over time, (2) sensitivity to treatment effect, (3) correlation with symptom severity, (4) correlation with global clinical ratings, and (5) correlation with other measures of health-related quality of life. Four hundred and twenty-three inpatients with schizophrenia participating in a clinical trial comparing clozapine and haloperidol (VA Cooperative Study in Health Services #17) were evaluated using multiple measures of health-related quality of life (Lehman Quality of Life Interview; Heinrichs-Carpenter-Hanlon Quality of Life Scale; Strauss-Carpenter Level of Function scale, and clinical response.) The Quality of Life Interview showed less sensitivity to change and treatment effect, as well as lower correlations with all other measures than the Quality of Life Scale and the Level of Function scale. The latter scales showed high sensitivity to both change and treatment effect, and moderate-high correlations with other measures and with each other. The Quality of Life Scale and the Level of Function scale rater assessments appeared to be substantially more sensitive to subtle change and treatment effects than the patient-reported Quality of Life Interview for clinical trials. Health-related quality of life in schizophrenia is a more heterogeneous concept than previously appreciated.  相似文献   
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BACKGROUND: This study compares the effect of clozapine and haloperidol and identifies other factors related to family burden as experienced by relatives of patients with refractory schizophrenia (DSM-III-R). METHOD: Of 423 patients participating in a multisite randomized clinical trial, 221 identified a family member who was actively involved in their care and who agreed to complete a standardized measure of family burden at 6 weeks and 3, 6, 9, and 12 months after randomization, simultaneous with comprehensive patient assessments. RESULTS: Patient factors most consistently correlated with greater family burden were symptom severity, days living in the community (i.e., not in the hospital), and frequency of family contact. Among family members, clozapine was associated with significantly (p = .048) greater reduction in feelings of dissatisfaction related to providing support to the patient, but not in objective measures of support, amount of worry the patient engendered, or days of missed employment or household activity. Although clozapine reduces symptoms, thus lowering family burden, it also increases days living in the community, which tends to increase family burden, perhaps canceling out the benefit to families of reduced symptoms. CONCLUSION: Clozapine has a small but significant effect on the experience of families of patients. This is the first study to demonstrate that effective pharmacotherapy may be of some benefit to families as well as to patients.  相似文献   
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Wood  GA; Korkola  JE; Lee  VM; Sarma  DS; Archer  MC 《Carcinogenesis》1997,18(9):1745-1750
Copenhagen (Cop) rats are completely resistant to the chemical induction of mammary adenocarcinomas, but their susceptibility to hepatocarcinogenesis is virtually unknown. Rat liver is a well- characterized and easily manipulated tissue in which to study carcinogenesis. Therefore, if Cop rats are resistant to hepatocarcinogenesis, studies into resistance mechanisms may be feasible. Male Cop and F344 rats, 7-8 weeks old, were initiated using either N-nitrosodiethylamine (DEN) (200 mg/kg, i.p.) or a two-thirds partial hepatectomy (PH) followed by N-methyl-N-nitrosourea (MNU) (60 mg/kg, i.p.). The rats were then promoted using a modified resistant hepatocyte (RH) protocol (a combination of four doses of 2- acetylaminofluorene (2-AAF) and a single dose of CCl4 that provides a selective mitotic stimulus for initiated cells). Six weeks after initiation the rats were killed and liver sections were stained for glutathione S-transferase 7-7 (GST 7-7), a marker for putative preneoplastic hepatocytes. Cop rats were found to be highly resistant, having a approximately 9- and approximately 27-fold smaller percentage of liver area occupied by GST 7-7-positive foci than susceptible F344 rats following initiation by DEN and MNU respectively. Furthermore, gross liver nodules did not form in any of the Cop rats, whereas all F344 rat livers contained nodules. Hepatic necrosis caused by DEN during initiation, and CCl4 during promotion is necessary to stimulate compensatory hepatocyte division. We demonstrated that these agents do indeed increase serum transaminase levels and produce histologic evidence of necrosis in Cop rats. In order for liver foci to grow rapidly in the RH protocol, the surrounding normal hepatocytes must be mito-inhibited by 2-AAF. We found that the degree of mito-inhibition of normal hepatocytes by 2-AAF is the same in Cop and F344 rats. These results show that the Cop rat is highly resistant to the chemical induction of putative preneoplastic liver foci and nodules.   相似文献   
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OBJECTIVE: To examine the characteristics of infants suffering from failure to thrive in a community based cohort in Israel and to ascertain the effect of failure to thrive on their cognitive development. METHODS: By review of records maintained at maternal and child health clinics in Jerusalem and the two of Beit Shemesh, epidemiological data were obtained at age 15 months on a cohort of all babies born in 1991. For each case of failure to thrive, a matched control was selected from the same maternal and child health clinic. At age 20 months, cognitive development was measured, and at 25 months a home visit was carried out to assess maternal psychiatric status by questionnaire, and the HOME assessment was performed to assess the home environment. RESULTS: 3.9% of infants were found to have fallen below the third centile in weight for at least three months during the first year of life. Infants with failure to thrive did not differ from the general population in terms of obstetric or neonatal complications, birth order, or parents' ethnic origin, age, or years of education. The infants with failure to thrive did have lower birthweights and marginally smaller head circumferences at birth. Developmental assessment at 20 months of age showed a DQ of 99.7 v 107.2 in the matched controls, with 11.5% having a DQ below 80, as opposed to only 4.6% of the controls. No differences were found in maternal psychiatric problems as measured by a self report questionnaire. There were, however, significant differences in subscales of the HOME scale. CONCLUSIONS: (1) Infants who suffered from failure to thrive had some physiological predispositions that put them at risk; (2) failure to thrive may be an early marker of families providing suboptimal developmental stimulation.  相似文献   
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