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991.
研究了不同温度、浓度条件下,顺丁烯二酸(顺酸)非催化反应网络,即顺酸可生成反丁烯二酸(反酸)和苹果酸,反酸与苹果酸存在可逆反应。建立了该反应网络的动力学模型。测定了不同反应条件下顺酸、反酸和苹果酸浓度随时间变化的规律,据此,动力学参数进行了估值。 相似文献
992.
本实验复制24只杂种犬心肌缺血再灌注损伤病理模型,应用与生理盐水、丹参对比的方法观察通脉灵对血液动力学及心功能的影响。结果表明,通脉灵小剂量组(TM1G)、通脉灵大剂量组(TM2G)和丹参对照组(DSG)的心输出量(CO),心脏指数(CI),心搏指数(SI)、左室内压峰值(LVSP)及左室内压最大变化速率(±dp/dtmsx)均明显高于生理盐水对照组(NSG)。本实验证明,通脉灵主要是通过保护心肌舒缩功能改善血液动力学指标进而防止缺血再灌注时心功能不全的发生。 相似文献
993.
Identification of Leishmania donovani isolates from different kala-azar foci in China by kDNA hybridization. 总被引:1,自引:0,他引:1
kDNA sequence homology of Leishmania donovani isolates from three types of kala-azar foci in China were analyzed by using dot and Southern hybridization with biotin- and 32P-labelled probes. The results revealed kDNA sequence heterogeneity among Leishmania donovani isolates from the three kala-azar foci: sequence homology between isolates of hill and desert foci was higher than that between hill and plain foci isolates. The kDNA hybridization technique was also found to be specific and sensitive for direct identification of Leishmania in animal tissues. In a preliminary survey, kDNA hybridization of cutaneous tissue blots of 71 dogs from endemic regions showed a positive rate of 40.8%, and the rate of double positive cases (touch blot hybridization and bone marrow smear) reached 91.3%. The direct identification of Leishmania in tissues by kDNA hybridization seems to be a useful and convenient method for epidemiological study and clinical diagnosis, especially for species/strain characterization. 相似文献
994.
S H Jacobson Y Wang H Jacobsson S Larsson C G Ostenson 《Nephrology, dialysis, transplantation》1992,7(11):1085-1091
Functional parenchymal kidney volume was determined by single-photon emission computed tomography (SPECT) for 99mTc-dimercaptosuccinic acid (DMSA) using a rotating gamma camera in phantom experiments and in patients with insulin-dependent diabetes mellitus (IDDM). The results from the patient examinations were corrected according to the phantom studies and were thereafter set in relation to renal haemodynamics, blood pressure, and urinary albumin excretion. Functional parenchymal kidney volume was significantly greater in diabetic patients compared to that of 11 healthy controls (P < 0.003). Urinary albumin excretion was increased and glomerular filtration rate (GFR) per renal parenchymal volume significantly less in patients with a duration of diabetic disease of more than 15 years compared to patients with shorter duration of disease (P < 0.03 and P < 0.05 respectively). Diabetic patients with a GFR of more than 120 ml/min had greater renal parenchymal volume than patients with lower GFR (P < 0.02). Patients with increased GFR, renal plasma flow (RPF), renal blood flow, or filtration fraction had significantly greater functional parenchymal volume than the healthy subjects (P < 0.01 for all comparisons). We conclude that by application of SPECT for DMSA we were able to show that IDDM patients have greater renal parenchymal volumes than healthy subjects. GFR/kidney volume was increased in IDDM patients with a duration of disease of < 15 years compared to patients with long-standing diabetes. The SPECT technique seems suitable for prospective long-term follow-up studies of functional kidney volume in IDDM patients. 相似文献
995.
Protective effect of Re-LPS antiserum on experimental multiple system organ failure. 总被引:2,自引:0,他引:2
This study examines the possible beneficial effect of Re-LPS (F515) antiserum on experimental multiple system organ failure (MSOF) in rabbits. The results showed that the plasma LPS level was significantly decreased, and it took a shorter period to clear up LPS in experimental than in control rabbits after receiving Re-LPS antiserum. Pretreatment with antiserum can markedly improve the function of the liver, lungs, kidneys, blood and gastrointestinal tract. The MSOF incidence in the group of rabbits receiving immune sera was only 11.2% and the survival rate was raised by about 40.0%. The results suggest that early passive immunotherapy may neutralize gut-derived endotoxin, inhibit endotoxin-induced mediators release and prevent development of severe complications due to sepsis. It is therefore postulated that LPS core antiserum may provide a prophylactic effect on the development of experimental MSOF.
相似文献
996.
997.
998.
Absence of memory for intraoperative information during surgery under adequate general anaesthesia 总被引:5,自引:3,他引:2
Using the isolated forearm technique (IFT), we wished to determine if
patients known to be unresponsive to commands during general anaesthesia
with nitrous oxide, halothane and neuromuscular blocking agents had any
evidence of explicit or implicit recall. Two groups of women, studied in a
single-blind sequential block design, heard different tapes, either a
command and information tape (n = 34) or radio static (n = 34), throughout
surgery. Four women (two radio static, two command) had unequivocal
evidence of explicit recall for a period near the beginning or end of the
procedure, at a time when the IFT was not being used. With or without
hypnosis, category generation, serial position of category exemplars and
word association tests did not reveal evidence of priming. We conclude that
during light general anaesthesia with nitrous oxide, halothane and
atracurium, patients had neither explicit nor implicit memory for
information presented during a period when they are known to be
unresponsive to commands.
相似文献
999.
煤烟型大气污染对儿童肺功能的影响 总被引:4,自引:1,他引:3
为观察煤烟型大气污染对儿童健康的影响 ,选择了太原市 3个污染程度不同地区的 45 0名儿童进行肺功能测试和问卷调查。研究结果显示 ,儿童呼吸功能表现为重度污染区 <中度污染区 <相对清洁区 ;肺通气功能阻塞性异常率表现为重度污染区 >中度污染区 >相对清洁区 ;Logistic回归分析发现肺通气功能阻塞性异常率与小学生家庭的取暖方式、厨房和卧室是否分开以及污染物的水平有关 ;多元线性回归分析显示重度污染区儿童的FVC、FEF5 0与相对清洁区相比分别减少了 65 80ml、119 2 7ml,中度污染区儿童的FVC、FEF5 0与相对清洁区相比分别减少了 5 7 2 8ml和 114 2 9ml;Ln(SO2 )每升高一个单位 ,FVC和FEF5 0分别减少69 10ml和 119 79ml,Ln(PM1 0 )每升高一个单位 ,FVC、FEF5 0等分别减少了 193 5 0ml和 171 69ml。结果提示 ,太原市煤烟型大气污染对儿童呼吸系统产生了危害。 相似文献
1000.
用电子计算机对核素、多普勒和心尖搏动图中的8项左室舒张功能指标进行判别分析,比较各指标与冠心病的密切程度。结果显示患者年龄和各项舒张功能指标明显不同于正常组。判别方程为:Z=0.21X_1+23.86X_2-22.88X_3-0.18X_4+2.83X_5+2.06X_6+66.86X_7+1.66X_8。临界值为42.99。判别正确率为100%。各指标的贡献率大小依次为EV/AV,1/3FF,A/E-O,PFR,DATI,EDC,IRT和1/3FFd。提示:多普勒EV/AV与冠心病的关系最为密切,核素的1/3FF次之,心尖搏动图的A/E~O亦是一个较好的指标。 相似文献