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101.
102.
An increase in intracellular Na+ during ischaemia has been associated with myocardial injury. In this study, we determined whether inhibition of Na+/K+ ATPase activity contributes to this increase and whether Na+/K+ ATPase activity can be maintained by provision of glucose to perfused rat hearts during low flow, 0.5 ml/min, ischemia. We used 31P NMR spectroscopy to determine changes in myocardial energetics and intracellular and extracellular volumes. 23Na NMR spectroscopy, with DyTTHA3- present as a shift reagent, was used to measure changes in intracellular Na+ and 87Rb NMR spectroscopy was used to estimate Na+/K+ ATPase activity from Rb+ influx rates, Rb+ being an NMR-sensitive congener of K+. In hearts provided with 11 mM glucose throughout ischemia, glycolysis continued and ATP was twofold higher than in hearts without glucose. In the glucose-hearts, Rb+ influx rate was threefold higher, intracellular Na+ was fivefold lower at the end of ischemia and functional recovery during reperfusion was twofold higher. We propose that continuation of glycolysis throughout low flow ischemia allowed maintenance of sufficient Na+/K+ ATPase activity to prevent the increase in intracellular Na+ that would otherwise have led to myocardial injury. 相似文献
103.
Low‐income urban parents of color enrolled in a parent training study were interviewed to understand what motivated their participation and what led 30% of them to subsequently drop out. Most enrolled because they wanted to be better parents. Most dropped out because of time and schedule constraints. Retention was higher when parents' motivations for participation matched program goals. Program location and qualities of the recruiter were cited most often as important; financial compensation was cited least often as important. 相似文献
104.
T. Bendix A. F. Bendix E. Busch A. Jordan Tom Bendix MD 《Scandinavian journal of medicine & science in sports》1996,6(2):88-97
Conventional treatments have not slowed down the ever expanding low back pain (LBP) problem. Traditional treatment has most probably contributed to the growth of the problem. Therefore, in a search for new solutions, 'functional restoration' has been devised. In connection with chronic LBP the term has been associated with a full-day program lasting from 3 to 5 weeks. it includes multidisciplinary treatment of patients in groups with intensive physical and ergonomic training, psychological pain management, back school, as well as teaching in social/work related issues. The key concepts are 'acceptance of the pain', 'activity', 'self-responsibility', 'multidisciplinary' and 'quantitative functional evaluation (QFE)'. The latter is aimed so that the participants can feel the physical improvement, encouraging them to be able to go back to work, or at least to lead a more active life style. Several controlled studies suggest a lasting effect in terms of regaining their ability to work and improving pain behavior for a good part of disabled chronic LBP patients. However, it is noteworthy that randomized studies seemingly show poorer results than studies not employing randomized controls. 相似文献
105.
近存活期分娩(PVB)儿各组织系统发育极不成熟,易发生各种器官功能损害和并发症,预后常不佳。目前关于PVB儿出生后早期管理的报道不多,诸多尚待解决的问题仍是围产医学所面临的挑战。经有效的新生儿复苏和呼吸循环支持、积极的营养支持和喂养、防治感染、内分泌和代谢性疾病管理、积极处理早产儿相关并发症,以及发育支持护理、家庭参与式护理等一系列个体化管理和精细化护理,四川省医学科学院·四川省人民医院成功救治了1例胎龄23周,出生体质量(BW)为450 g的PVB儿。本文通过总结1例PVB儿的出生后早期管理,并结合文献复习进行归纳总结,以期为提高BW<500 g的PVB儿存活率并获得良好预后提供经验及借鉴。 相似文献
106.
背景 针灸是治疗慢性非特异性腰痛(CNSLBP)的重要方法。随着研究的发展,大量针灸治疗CNSLBP的随机对照试验(RCT)已经发表,但由于在结局指标选择方面存在一定的问题,严重限制了高质量临床证据的产生。目的 评价针灸治疗CNSLBP RCT选用的结局指标情况,为针灸治疗CNSLBP相关研究提供参考依据。方法 系统检索4个中文数据库(中国知网、维普网、万方数据知识服务平台、中国生物医学文献服务系统)、3个英文数据库(PubMed、Embase、Cochrane Library)2017-01-01至2022-03-15发布的针灸治疗CNSLBP的文献,以及自建库以来至2022-03-15发表的非特异性腰痛(NSLBP)的核心结局指标集(COS)。对纳入的针灸治疗CNSLBP的文献基本特征进行分析,对文献的临床结局指标进行归类,对文献中的结局指标及《中医病证诊断疗效标准》的应用现状进行分析。分析NSLBP研究的COS现状,比较其与现有针灸治疗CNSLBP文献结局指标的异同。结果 本研究纳入的针灸治疗CNSLBP的49篇文献均为RCT,共包含4篇英文文献和45篇中文文献。共包含4 272... 相似文献
107.
Wolf Szmuness Cladd E. Stevens Edward J. Harley Edith A. Zang Patricia E. Taylor Harvey J. Alter The Dialysis Vaccine Trial Group 《Journal of medical virology》1981,8(2):123-129
Three hundred thirty-six medical personnel from hemodialysis centers were treated with three doses, 20 μg each, of the Merck hepatitis B vaccine (at 0, 1, and 6 months). Within 1 month after the first injection, 41% converted to anti-HBs positivity; after the second injection the conversion rate rose to 80–90%; and after the booster, to 96–98%. The later rate remained unchanged during the 18-month follow-up period. Only 2.8% of those vaccinated did not respond to the vaccine. The patterns of immune responses to 20-μg doses were found to be exactly the same as to 40-μg doses. It is suggested that reduced doses of vaccine should be as efficacious as the larger ones. 相似文献
108.
InDrosophila ananassae, artificial selection was carried out for high and low mating propensity for 15 generations. Response to selection was from about F5, with rapid divergence in mating frequencies in replicates of both fast and slow lines. To assess the effect of selection on the two sexes, females and males of the selected lines were tested against their respective counterparts of the control line after 15 generations. Significant differences in mating propensity were observed when selected males were tested against the control females, which suggests that males were much more affected by selection than females. After 15 generations the fast and slow lines (both replicates) were crossedinter se and mating frequencies of F1 hybrids were studied in the same way as during the selection experiment. F1 flies had a higher mating activity compared to their parental lines when males were derived from fast lines to produce hybrids. On the other hand, F1 hybrids produced by crossing slow-line males with fast-line females showed mating frequencies similar to those of the slow parental lines. These findings suggest that mating propensity inD. ananassae is under the control of polygenes. Furthermore, the significant differences in mating propensity of hybrids produced by the fast and slow males indicate the possibility of a Y-linked influence on mating propensity inD. ananassae.The present investigation was carried out during the tenure of a senior research fellowship of the CSIR, New delhi, to S.C. 相似文献
109.
Fluid Flow through Filtering Appendages of Insects 总被引:4,自引:0,他引:4
Many organisms use structures composed of arrays of cylindersto capture particulate food or molecules form the water or airaround them. The performance of such filters depends on thevelocity of fluid movement through them; hence, mathematicalmodels of flow through fibrous structures can provide insightsabout the functional morphology of biological filters. In thispaper, the authors address the case of feather-like biologicalfilters of finite width and assess several possible models forfluid motion through them by comparing model predictions withobservational data. Two examples of insect appendages are considered:the cephalic fans of black fly aquatic larvae that capture particulatefood and the antennae of adult male moths that catch sex-attractantmolecules released by female moths. The results suggest thatflow through such structures can be much slower than ambientcurrents, that the finest hairs in the structure are the morphologicalfeatures with the greatest effect on leakiness, and that thevelocity of movement (or of ambient flow), as well as the morphologyof such filters, can be critical in determining their performance. 相似文献
110.
磷酸盐型低密度脂蛋白亲和吸附剂制备与体外吸附试验研究 总被引:1,自引:0,他引:1
研究目的是制备低密度脂蛋白亲和吸附剂,用于去除高脂血症患者血液中高含量的低密度脂蛋白。首先以悬浮分散法制备壳聚糖微球和纤维素微球载体,然后固定磷酸吡哆醛和磷酸盐配基,制备出三种吸附剂,并进行体外静态吸附性能测试。结果表明,壳聚糖-磷酸吡哆醛吸附剂对LDL最大吸附量为1.30mg/mL,磷酸盐型壳聚糖和纤维素吸附剂对LDL的最大吸附量分别为2.72mg/mL和3.12mg/mL,并且吸附量随配基含量的增加呈增大趋势,3种吸附剂对高密度脂蛋白均无明显吸附。对吸附剂的灭菌和储存稳定性的研究表明,磷酸盐型纤维素吸附剂具有较好的稳定性。本研究第一次报道磷酸盐型低密度脂蛋白吸附剂。 相似文献