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91.
目的:观察缺氧及停止缺氧后对大鼠心肌血流量的影响。方法:34只Wistar大鼠,随机分为4组:①平原对照组;②急性缺氧组;③慢性缺氧组;④返回平原组。以放射性生物微球法测定心肌血流量。结果:急性缺氧引起PaO2、心输出量及氧运送量降低,但左、右心室心肌血流量明显增加;慢性缺氧时右心室收缩压、血球压积、血液粘滞性及右心室生理指数明显增加,而心肌血流量接近正常。停止缺氧30d后,上述所有指标均与平原以 相似文献
92.
目的建立重庆市正常牙合青少年牙颌模型牙列指数的正常值,为正畸临床提供依据.方法选取重庆市正常牙合青少年牙颌模型92付(男45付,女47付),测量牙冠宽度、牙弓宽度,计算Bolton指数和Pont指数,对测量结果进行统计分析并与国内外相关资料进行对比研究,对Bolton指数和Pont指数的临床应用价值进行评价.结果Bolton指数和Pont指数存在种族和地区差异,结论Bolton指数和Pont指数在正畸临床中均有一定的应用价值,临床上应参照本民族和地区的标准. 相似文献
93.
Auditory evoked potential index: a quantitative measure of changes in auditory evoked potentials during general anaesthesia 总被引:30,自引:0,他引:30
We describe a novel index derived from the auditory evoked potential, the auditory evoked potential index, and we compare it with latencies and amplitudes related to clinical signs of consciousness and unconsciousness. Eleven patients, scheduled for total knee replacement under spinal anaesthesia, completed the study. The initial mean (SD) value of the auditory evoked potential index was 72.5 (11.2). During the first period of unconsciousness it decreased to 39.6 (6.9) and returned to 66.8 (12.5) when patients regained consciousness. Thereafter, similar values were obtained whenever patients lost and regained consciousness. Latencies and amplitudes changed in a similar fashion. From all parameters studied, Na latencies had the greatest overlap between successive awake and asleep states. The auditory evoked potential index and Nb latencies had no overlap. The consistent changes demonstrated suggest that the auditory evoked potential index could be used as a reliable indicator of potential awareness during propofol anaesthesia instead of latencies and amplitudes. 相似文献
94.
东北地区风寒指数气候特征与冷习服锻炼日期的确定 总被引:2,自引:0,他引:2
应用中国东北48个站10年的逐日气象资料,分析了风寒指数(Vt)的候、月、旬、日平均值,据此,提出了各地可供冷习服锻炼的天数及可开始锻炼的日期等。研究结果在生物气候区划和指导部队耐寒锻炼等方面有重要作用,也有助于较精确的估算冷应激强度及寒冷环境对作业能力影响的预测。 相似文献
95.
深低温对吸入麻醉药的MAC,心脏麻醉指数和心肌稳定性的影响 总被引:3,自引:1,他引:2
目的:研究深低温对吸入麻醉药MAC、心脏麻醉指数和心肌稳定性的影响。方法:新西兰白兔40只,随机分为氟烷、安氟醚、异氟醚和七氟醚组。采用夹尾试验法测定常温下(38℃±0.5℃)的最低肺泡有效浓度(MAC)。行体表降温后测定深低温下(23℃±0.5 ℃)的MAC。维持深低温增加吸入性麻醉药的浓度,同时用50Hz、25V电压胸外电击心脏。记录出现室颤或室性心律失常时的肺泡呼气末吸入麻醉药浓度。结果:从38℃到23℃兔体温每降低1℃,MAC下降值为:氟烷5.1%、安氟醚3.6%、异氟醚4.4%、七氟醚4.3%;氟烷、安氟醚、异氟醚和七氟醚心脏麻醉指数分别为4.4、3.18、6.25和4.6,异氟醚明显高于其它麻醉药;麻醉药浓度8MAC以内安氟醚和氟烷发生室颤的机率(100%)明显高于七氟醚和异氟醚(40%)。结论:异氟醚是深低温麻醉的最佳选择用药,而安氟醚则不宜用于低温麻醉。 相似文献
96.
Tamaki Sasaki Tetsuya Sato Yoshiyuki Jyo Nobuya Tanda Hitoshi Tamai Gengo Osawa 《Clinical and experimental nephrology》1997,1(1):32-40
Background We previously found that glomerular epithelial cells play an important role in the formation of adhesive lesions. Glomerular
sclerotic lesions develop after the inital adhesive lesions.
Methods Two series of experiments were done with spontaneously diabetic WBN/Kob rats. These rats develop segmental glomerular sclerotic
lesions with aging. The first series of experiments was intended to clarify the kinetics of glomerular cells on progressive
glomerular damage in these rats. The second series of experiments was designed to study the relationship between proliferation
(judged by % bromodeoxyuridine-positive cells) of glomerlar epithelial cells and sclerotic lesions with adhesions.
Results In the first series, rats having increased proteinuria showed segmental glomerular sclerotic lesions with adhesions. At the
same time, increased labeling indices of tuft cells and epithelial cells of Bowman's capsule were observed. In the second
series, no significant increase in the labeling indices of tuft cells with sclerotic lesions was observed, compared to tuft
cells without sclerotic lesions. In sclerotic lesions with adhesion, bromodeoxyurdine-positive cells were observed that were
not distinguishable as podocytes or epithelial cells of Bowman's capsule. The highest labelling index was noted in the epithelial
cells of Bowman's capsules with sclerosis.
Conclusion This study shows that the proliferation of glomerular epithelial cells (mainly epithelial cells of Bowman's capsule) occurs
in glomerular sclerotic lesions with adhesions. 相似文献
97.
1996年1~2月份调查了全市30个冷库131份海产品,127份挥发性盐基氮指标符合国家卫生标准,合格率为96.95%。说明仍有极少的海产品有腐败变质现象,为保证消费者食用安全,建议每月检测一次挥发性盐基氮。关于鲜度分级问题,我们认为食品标准是关系到人民健康的强制性标准,制定标准的先决条件是消费者食用后对身体不造成危害,因此作为卫生标准不分级为好,其鲜度指标只要符合标准规定,就应允许销售食用。 相似文献
98.
老年2型糖尿病患者胰岛素抵抗相关指标的检测和意义 总被引:1,自引:1,他引:0
目的:探讨老年2型糖尿病胰岛素抵抗(IR)及其相关性,为老年2型糖尿病的合理防治提供临床依据。方法:选择120例老年2型糖尿病患者,按胰岛素敏感指数(HOMA)胰岛素抵抗(HOMA-IR)50百分位点将患者分为两组:胰岛素相对敏感组(HOMA-IR<3.56)和胰岛素相对抵抗组(HOMA-IR≥3.56),比较体重指数(BMI)、腰/臀比(WHR)、血压、血生化学检查等指标。用年龄>40岁,<60岁的2型糖尿病患者做对照组。结果:两组老年患者在年龄、性别、舒张压、空腹血糖、胆固醇、高密度脂蛋白、糖化血红蛋白、HOMA胰岛β细胞功能方面无差异;但BMI、WHR、收缩压、甘油三脂、空腹胰岛素、HOMA-IR差异具有显著性。多线性回归分析后,只有腰/臀比、收缩压、甘油三脂、HOMA-IR存在统计学差异。老年患者与对照组相比,IR发生率明显增加,且两者腰/臀比、收缩压、甘油三脂方面也差异显著。结论:IR与老年2型糖尿病密切相关,是临床防治糖尿病的重要靶点。 相似文献
99.
100.
Abstract
Background. To avoid the adverse consequences of abdominal compartment syndrome and to reduce the high mortality the celiotomy wound
in patients with abdominal sepsis was closed without tension using prosthetic mesh. This produces a semiopen situation that
permits staged reinterventions together with the functional reconstitution of the continuity of the abdominal wall.
Material and Methods. Twenty-five patients with intra-abdominal sepsis of various causes were evaluated retrospectively to assess the results of
semiopen management of the septic abdomen and reoperations on demand in severe peritonitis. All of the patients were in a
state of neglected peritonitis, and had at least one failing organ system. The Mannheim Peritonitis Index (MPI) scoring system
was used for stratification of abdominal sepsis.
Results. The mean MPI score of 25 patients was 24, ranging 10 to 33. Eight (32%) patients were reexplored (MPI=21). There were overall
9 (36%) complications in patients with mean MPI score of 23. Six (24%) mesh-related complications (infection and enterocutaneous
fistulas) developed (MPI=19). The mean MPI score of patients without complications was 24. Four (16%) patients died with index
MPI score of 26 due to fulminant hepatitis, myocardial infarction, and multiple organ failure. The admission period averaged
63 days.
Conclusions. In 25 critically ill patients with abdominal sepsis the mortality was lower than expected, relative to heterogeneous data
from the literature; also, major complications occurred less frequently although the mean MPI score was high. The authors
conclude that this approach is a reliable contribution to the complex treatment of these patients.
Electronic Publication 相似文献