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151.
Demographic and risk factors associated with chronic dieting in adolescents   总被引:3,自引:0,他引:3  
A comprehensive, school-based survey was administered to 36,320 Minnesota public school students in grades 7 through 12 during the 1987-1988 school year. Self-reported chronic dieting was much higher in girls than in boys (12.1% of all girls vs 2.1% of boys). For girls, the percentage of chronic dieters was significantly less in grades 7 and 8 (7.8%) than in grades 9 and 10 (13.5%) or grades 11 and 12 (14.3%). There were no differences among urban, suburban, or rural youth. Black girls were less likely to diet compared with white girls. Chronic dieters were more likely than other students to report maladaptive weight-loss techniques, such as self-induced vomiting (relative risk, 9.92 for girls and 9.40 for boys), laxative use (relative risk, 7.18 for girls and 11.00 for boys), ipecac use (relative risk, 8.33 for girls and 11.00 for boys), and diuretic use (relative risk, 7.30 for girls and 13.5 for boys). It is suggested that chronic dieting may serve as a screening marker for more severe eating and weight-loss behaviors.  相似文献   
152.
The relationship between alcohol use and injury severity was investigated in trauma patients admitted to a tertiary referral hospital during a 23-month period. Admission blood alcohol levels (BALs) were obtained on 427 trauma patients, who were stratified into three groups: those with no measurable blood alcohol, those within the legal limit of 100 mg/dL, and those over the legal limit or intoxicated. The no-alcohol group had significantly lower injury severity than the other two groups (p less than 0.001). Even when the BAL was well within the legal limit, injuries suffered by those in the alcohol-positive groups were more severe than those in the no-alcohol group. Confirmatory evidence of the effect of alcohol on injury severity was reflected by a 2.3% mortality in alcohol-negative patients compared with a 13.3% death rate in alcohol-positive patients (p less than 0.0001). To assess the potentially confounding effect of alcohol on injury scoring accuracy, we examined the change in Glasgow Coma Scale (GCS) scores following admission. No significant differences were found when admission GCS values were compared with GCS determinations made 24 hours following admission by separate observers. To correct for any potential bias as a tertiary referral center, repeat analysis with exclusion of transferred patients was done with essentially no change in results. Our data revealed a highly significant relationship between alcohol use, degree of injury, and resource consumption.  相似文献   
153.
Mammographic detection of recurrent cancer in the irradiated breast   总被引:4,自引:0,他引:4  
Recurrence of cancer in the irradiated breast is an uncommon but potentially curable problem. Posttreatment mammograms were studied in 45 patients who had biopsies of an irradiated breast for suspected local recurrence to evaluate the usefulness of mammography in detecting such recurrences. Of 23 biopsy-proven recurrences, eight (35%) were detected by mammography only, nine (39%) were detected by physical examination only, and six (26%) were detected by both. Mammographic findings in recurrent malignancy included microcalcifications in six, microcalcifications associated with a mass in four, soft-tissue masses in three, and inflammatory changes in one. The results show that mammographic follow-up is complementary to physical examination in the detection of local recurrence in women who have undergone radiation therapy for early breast cancer.  相似文献   
154.
The synthesis, biological evaluation, and structure-activity relationships of a series of 1-(pyridylphenyl)-1-phenyl-2-imidazolylethanols are described. These compounds show potent dose-dependent topical antiinflammatory activity in murine models of skin inflammation. This effect is likely due to inhibition of cytochrome P450 and consequent reduction in levels of 12R-HETE in the skin. These compounds were examined for their ability to inhibit the oxidative metabolism of arachidonic acid; they specifically inhibit the formation of prostacyclins in mouse macrophages. To study the effects of structure on the in vivo activity, three general features of the molecules were varied: the position of attachment of the pyridine nucleus (A), the second aromatic residue (B), and the nitrogen base on the ethanol chain (C). 1-[4-(4-Pyridyl)phenyl]-1-(4-fluorophenyl)-2- imidazolylethanol (2a, DuP 983) shows a very attractive profile of antiinflammatory activity and has been selected for clinical evaluation as a topical antiinflammatory agent.  相似文献   
155.
156.
苯丙胺诱发小鼠激怒反应及其机制   总被引:1,自引:0,他引:1  
徐建华  沈洪  章元沛 《药学学报》1992,27(8):566-571
苯丙胺15mg/kg ip能诱发小鼠激怒反应,使小鼠出现攻击和殴斗行为。强安定药、弱安定药和利血平有明显拮抗效果。镇静剂如巴比妥类、抗胆碱药及抗肾上腺素药均无拮抗作用。金刚胺、左旋多巴和阿扑吗啡均能增强苯丙胺的激怒效应。因苯丙胺激怒小鼠的方法简便易行,可作为筛选抗精神病药的动物模型。苯丙胺产生激怒作用的机制与增强多巴胺能神经的功能有关,推测可能是促进边缘系统多巴胺释放的结果。  相似文献   
157.
The recently introduced Technicon H1 analyser uses an improved optical principle to measure the size and haemoglobin concentration of erythrocytes. We have made a serial study of ten patients undergoing phlebotomy to induce mild iron deficiency. The instrument showed the early development of anisohypochromia with subsequent fall in the mean cell haemoglobin concentration (MCHC). Cell volume was preserved until relatively late and during early iron deficient erythropoiesis cell volume would appear to be maintained at the expense of haemoglobin concentration. The Technicon H6000 (conventional technology) used in parallel produced contrasting results indicating anisomicrocytosis with preservation of cell haemoglobin concentration until relatively late. Five cases of severe iron deficiency treated with iron were similarly studied and showed comparable changes on both instruments, with characteristically bimodal cell volume histograms and large increases in red cell distribution width. Our results indicate that the new generation of instruments will generate red cell data of additional clinical value.  相似文献   
158.
159.
The Liverpool Congenital Malformations Registry   总被引:1,自引:0,他引:1  
Data collection and validation for the Liverpool Congenital Malformations Registry (LCMR) are described. Founded in 1960, the LCMR increased its area of surveillance in 1979 to include five health districts in Liverpool and its environs with approximately 20,000 births per annum. The LCMR is now one of the members of the European Congenital Anomalies Register (EUROCAT). Multiple sources of ascertainment are employed, the most useful of these being OPCS notifications, hospital discharge letters and data from specialised paediatric units. In spite of several difficulties encountered in data collection the data base is an invaluable tool both for routine monitoring of prevalence rates and as a starting point for epidemiological research.  相似文献   
160.
Regional cerebral blood flow (CBF) was studied with O(15)-water positron emission tomography and anatomic region-of-interest analysis on co-registered magnetic resonance in patients with idiopathic (n = 12) and secondary (n = 5) normal pressure hydrocephalus (NPH). Mean CBF was compared with values obtained from healthy volunteers (n = 12) and with clinical parameters. Mean CBF was significantly decreased in the cerebrum and cerebellum of patients with NPH. The regional analysis demonstrated that CBF was reduced in the basal ganglia and the thalamus but not in white matter regions. The results suggest that the role of the basal ganglia and thalamus in NPH may be more prominent than currently appreciated. The implications for theories regarding the pathogenesis of NPH are discussed.  相似文献   
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