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排序方式: 共有525条查询结果,搜索用时 18 毫秒
1.
This article examines the distribution of positive blood alcohol levels (BALs) among emergency room patients and the relationship between intoxication and other variables. Approximately one-quarter of the 640 subjects had positive blood alcohol levels and 16.3% had BAL readings above 0.10%, the legal limit for operating a motor vehicle in most states. Chi-square tests and logistic regression analysis indicated a significant relationship between employment status, gender, educational attainment, age and BAL. There were no significant racial differences. Analysis of the role of the presenting problem with BAL revealed that being involved in an accident was significantly predictive of a high BAL in a multivariate context. However, patients presenting with psychiatric problems had overall higher levels of intoxication than other patients. These findings have major implications for public policy formulation vis-à-vis public health delivery. 相似文献
2.
Leukotriene (LT) receptors in the guinea-pig ileum were characterized using LTB4, LTC4, LTD4 and LTE4 and the LT antagonists FPL 55712, ICI 198615 and (+/-)SKF 104353. LTB4 was inactive but the other LTs induced concentration-related contractions. LTC4 responses differed to those induced by LTD4 or LTE4. Inhibitors of LT metabolism had no significant effects on any LT responses. LTD4 contractions were inhibited by all three antagonists but a resistant response was apparent at concentrations of ICI 198615 greater than 10(-8) M. All three antagonists were weak/inactive against LTC4. LTE4 was a partial agonist which antagonized LTD4 responses but had little or no activity against LTC4 or histamine. These results suggest that two distinct LT receptor types exist on guinea-pig ileum. One type is predominantly activated by LTD4 and is antagonized by three structurally distinct LT antagonists and the partial agonist LTE4. The second type is predominantly activated by LTC4 and is insensitive to the LT antagonists. 相似文献
3.
K L O'Neill V J McKelvey M Hoper H Monteverde G W Odling-Smee H Logan W P Abram P G McKenna 《Medical laboratory sciences》1992,49(4):244-247
Thymidine kinase (TK) exists in two forms, TK1 and TK2. TK levels and oestrogen receptor status (OR) were measured in tumours from 86 patients with operable breast cancer and the patients were monitored for recurrence over 24 months. During the monitored period, 13 patients showed recurrence. These patients also exhibited higher total TK levels per mg tumour (P < 0.01) and higher TK1 levels (P < 0.001) than those who did not show recurrence. TK1 levels relative to TK2 were significantly higher (P < 0.05) in OR-negative tumours (n = 29) than in OR-positive tumours (n = 57). OR-negative (n = 9) and OR-positive (n = 4) patients who recurred had significantly higher TK1 levels relative to TK2 than did those who not recur (n = 20 and n = 53, respectively). These preliminary results indicate that breast tumour TK levels may have value in determining prognosis. 相似文献
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The effects of isometric contraction (66% of maximal force) and recovery on glycogen synthase fractional activity (GSF) in human skeletal muscle have been studied. Biopsies were taken from the quadriceps femoris muscle at rest, at fatigue and 5 min postexercise on two occasions: after one of the contractions, the circulation to the thigh was occluded during the 5 min recovery (OCC), and after the other contraction, the circulation was intact (control, CON). During CON, GSF decreased from (mean ± SE) 0.34±0.05 at rest to 0.24±0.02 at fatigue and then increased to 0.74±0.04 at 5 min postexercise; corresponding values for OCC were 0.37±0.04, 0.25±0.04 and 0.48±0.05 (P<0.001 vs. CON for 5 min postexercise only). Compared with the value at fatigue, protein phosphatase activity (PP) increased by 79±16% during CON recovery (P<0.01), whereas no change was observed during OCC recovery. Uridine diphosphate glucose increased by approximately 2.5-fold at fatigue, remained elevated during OCC recovery, but reverted to the preexercise level during CON recovery (P<0.001 vs. OCC recovery). Glucose 6-P increased approximately 5-fold at fatigue and was higher at 5 min postexercise in OCC vs. CON recovery (8.6±1.5 vs. 4.1±0.9 mmol/kg dry wt; P<0.01). It is concluded that the rapid increase in GSF after intense exercise with an intact circulation may be at least partly attributed to an increase in the specific activity of PP. The increase in GSF during recovery in OCC may be at least partly attributed to the high glucose 6-P content in vivo, which enhances the substrate suitability of GS for PP. Thus, separate mechanisms exist for the activation of PP and GS during recovery from intense short term exercise. 相似文献
7.
Wagner Abram L. Porth Julia M. Wu Zhenke Boulton Matthew L. Finlay Jessica M. Kobayashi Lindsay C. 《Journal of community health》2022,47(3):408-415
Journal of Community Health - It is important to distinguish between apprehensions that lead to vaccine rejection and those that do not. In this study, we (1) identifed latent classes of... 相似文献
8.
Irving Lutsky Margaret Hopwood Stephen E. Abram James M. Cerletty Raymond G. Hoffman John P. Kampine 《Journal canadien d'anesthésie》1994,41(7):561-567
In order to determine the prevalence of psychoactive substance use in three specialty groupings, 1,624 questionnaires were sent to physicians in medicine, surgery and anaesthesia; all had trained at the same academic institution. A response rate of 57.8% was achieved. Comparison of prevalence of impairment rates showed no differences between Surgery (14.4%), Medicine (19.9%) and Anaesthesia (16.8%). Substance abuse was clearly associated with a family history of abuse; 32.1% of the abusers had a family history of such abuse compared with 11.7% of the non-abusers. Increased stress at various career stages did not appear to increase substance abuse; problem areas during medical life times were similar for each specialty. Substances most frequently used were marijuana (54.7%), amphetamines (32.9%); and benzodiazepines (25.1%). Seventy-three used psychoactive drugs which were non-prescribed. Drug counselling programmes were judged inadequate by most. Use of alcohol and drugs by faculty members was reported by a number of respondents. 相似文献
9.
Genetic manipulation of mammary epithelium by transplantation 总被引:2,自引:0,他引:2
Genes can be introduced into mammary epitheliumin vivo by the tissue reconstitution method. Primary cultures of mammary epithelial cells are prepared, a gene introduced using retrovirus vectors, and the cells transplanted into a mammary fat pad from which the normal epithelium has been removed. The cells reform an epithelium in which some cells express the introduced gene. The technique is reviewed and compared with the mammary-specific expression of genes in transgenic mice. To model the development of neoplasia, particularly the preneoplastic changes caused by a single oncogene alone, several oncogenes have been expressed this way—myc, Ha-ras, erbB, erbB2,Wnt-1, andhst/FGF-4. Each caused a different alteration to the growth pattern of the epithelium, such as altered branching, premature alveolus development, distorted duct structure, or altered hormone sensitivity. Insights into normal development have also been obtained by inappropriate expression of genes such asWnt-4. 相似文献
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