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The aim of this study was to assess the reproducibility of a number of simplified clearance methods using chromium-51 ethylenediamine tetraacetic acid (51Cr-EDTA) and to compare these with the multiple blood sample technique. Twenty-four healthy volunteers were enrolled into the study. The test was performed twice, 1 week apart and under similar physiological conditions. After intravenous injection of the tracer, 13 blood samples were taken between 5 and 240 min. The reference clearance was calculated after adapting a bi-exponential fit on the whole plasma disappearance curve. Simplified methods included the slope intercept method using different combinations of blood samples (2 and 4 h; 2, 3 and 4 h; 1.5, 2, 3 and 4 h; 1.5, 2 and 3 h) and several single clearance methods (Constable 3 h; Groth 3 h; Groth 4 h). The standard deviation of the differences between the first and second measurements were similar for all methods, confirming the comparable reproducibility of these methods.  相似文献   
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OBJECTIVE: In the present study, physical and sexual abuse among incarcerated youth were examined with respect to sexual activity, contraceptive use, and pregnancy. METHOD: The self-report survey data were collected from 62 females and 334 males who were incarcerated in Nevada youth correctional facilities in the summer of 1994. Of the males, 46.8% (n = 156) reported a history of physical abuse and 9.9% (n = 33) reported sexual abuse. A surprisingly high 73% (n = 46) of the females reported a history of physical abuse and 68.3% (n = 43) reported sexual abuse. RESULTS: The analyses indicated that females who reported a history of sexual abuse had an earlier mean age of first intercourse than those who reported no sexual abuse. In addition, male and female respondents with a history of physical and/or sexual abuse reported using no method of contraception as compared to youth with no history of abuse. CONCLUSIONS: Implications of these results for detention-based counseling and prevention programming are discussed.  相似文献   
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OBJECTIVE: To determine trends in gang homicides and the population at greatest risk for homicide by reviewing all gang-related homicides in Los Angeles County, California, from January 1979 to December 1994. DESIGN: Homicide files of the Los Angeles Police Department and the Los Angeles County Sheriff's Department from 1979 to 1994 involving violent street gang activity were reviewed. Gang files were reviewed for demographic data, weapons used, homicides by drive-by shootings, and times and geographic areas of occurrence. SETTING: Los Angeles County from January 1, 1979, to December 31, 1994. MAIN OUTCOME MEASURES: Age, race, and sex of gang-related homicide victims; frequency of weapon use; and the change in gang-related homicide rates during the study period. RESULTS: A total of 7288 gang-related homicides occurred in Los Angeles County from 1979 through 1994; 5541 of these homicides occurred in Los Angeles Police Department and Los Angeles County Sheriff's Department jurisdictions. During the study period, the proportion of all homicides that were gang related increased from 18.1% to 43.0% (P < .001). Of the 5541 gang-related homicide victims, 4580 (85.6%) were aged 15 to 34 years, 93.3% were African American or Hispanic, 5157 (93.2%) were male, 3559 (64.2%) were gang members, and 1408 (25.4%) occurred during drive-by shootings. Firearms were used in an increasing proportion of homicides, from 71.4% in 1979 to 94.5% in 1994. Homicides by semiautomatic handguns dramatically increased during the study period. Gang-related homicide rates for African-American males aged 15 to 19 years increased from 60.50 per 100,000 population per year in 1979 to 1981 to 192.41 per 100,000 population per year in 1989 to 1991. CONCLUSIONS: Gang-related homicides in Los Angeles County have reached epidemic proportions and are a major public health problem. To prevent gang violence, the root causes of violent street gang formation must be alleviated, the cycle of violent street gang involvement must be broken, and access to firearms must be limited.  相似文献   
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Patient often think that the pains of their extremities (especially during the night) are caused by a plebo or an angiopathy whereas they are in fact due to a vertebral or lumbar discal affection. 84 patients with osteoporosis were treated by an intramuscular injection of deca-durabolin (25 mg/month) and calcium phosphate (tertiare). Results were satisfactory: six months later, 62 patients no longer suffered, 13 had felt improvement and 2 remained unchanged.  相似文献   
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It is well known that diabetic patients are at an increased risk of the earlier development of significant atherosclerotic disease. We wish to report the case of a young insulin-dependent diabetic with an 18 months history of rapidly progressing 'diabetic' retinopathy who presented with right-sided weakness and was found to have severe carotid artery disease. We suggest that the sudden proliferation in his retinopathy was due to retinal ischaemia secondary to the carotid artery stenosis and we wish to present this as a case of ocular ischaemic syndrome in a young diabetic patient.  相似文献   
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