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41.
ABSTRACT. The effects of procedures which stimulate sympathetic activity, viz. mental stress induced by a colour-word conflict test (CWT) for 20 min, and orthostasis (ORT) for 8 min were studied in 8 young (16-20 yr) insulin-dependent diabetes mellitus (IDDM) patients and 9 age and sex-matched healthy controls. The IDDM patients showed no signs of neuropathy or retinopathy and their mean HbA1c value was 8.4 ±0.6% (normal value < 5.0 %). Blood pressure and heart rate increased significantly during CWT and ORT in both groups. The changes in systolic blood pressure and heart rate were comparable in both groups during CWT; the IDDM group showed a higher ( p < 0.05) heart rate after 8 min of orthostasis, however. CWT and ORT elicited equivalent increases in noradrenaline in venous plasma in both groups ( p < 0.05), but the IDDM patients had 50% lower values ( p < 0.01) at rest, during CWT and at rest after CWT than controls. CWT and ORT evoked equivalent plasma adrenaline increases in both groups. The lipolysis marker, plasma glycerol, was about 40 % lower ( p < 0.05) in the IDDM group before and after CWT. Yet, mental stress evoked equivalent increases in glycerol levels ( p < 0.01) in both groups. These findings indicate that sympathetic activity in the young diabetic patients without signs of neuropathy may be blunted. 相似文献
42.
Gérald Vanzetto Marc Janier Daniel Fagret Luc Cinotti Xavier André-Fouet Michel Comet Jacques Machecourt 《European journal of nuclear medicine and molecular imaging》1997,24(2):170-178
The best test presently available to ascertain residual viability within an infarct-related area involves the use of fluorine-18
fluorodeoxyglucose (FDG) to detect the persistence of some cellular metabolism. Rest reinjection of thallium-201 is a less
accurate alternative but is easy to perform. Iodinated fatty acids, which are used with standard gamma cameras, are proposed
as markers of cellular metabolism. This study was performed to assess the value of 16-iodo-3-methyl-hexadecanoic acid (MIHA)
as a marker of the residual cellular metabolism by comparison with FDG in patients with a recent myocardial infarction, and
to evaluate its contribution compared with the201Tl stress-redistribution-reinjection technique. Stress-redistribution-reinjection201T1 imaging, rest MIHA imaging and glucoseloaded FDG imaging were performed in 22 patients with recent myocardial infarction.
Out of the 628 myocardial segments obtained from the left ventricular analysis, 400 were hypoperfused (relative uptake <0.75
of maximum uptake on stress201T1 imaging), 177 of which were severely hypoperfused (relative uptake <0.50). Receiver operating characteristic (ROC) curves
for predicting metabolic myocardial viability with FDG were derived from the results in respect of (a)201T1 activity during exercise, redistribution and reinjection and (b) MIHA up-take, using the two FDG thresholds most commonly
considered to define metabolic viability (0.50 and 0.60). Analysis of the 400 hypoperfused segments demonstrated that201T1 reinjection was the most accurate test in predicting the presence of myocardial viability (area under the ROI curves=0.85
and 0.86 at the 0.50 and 0.60 FDG thresholds, respectively;P<0.05 vs other tests). The global predictive values of MIHA and201T1 reinjection were, respectively, 0.87 and 0.89 at the 0.50 FDG threshold (NS), and 0.82 and 0.87 at the 0.60 FDG threshold
(NS). When only the 177 severely hypoperfused segments were considered,201T1 reinjection remained the most accurate test (accuracy 0.84 at the 0.50 FDG threshold and 0.82 at the 0.60 FDG threshold),
while the accuracy of MIHA decreased significantly (0.78 at the 0.50 FDG threshold and 0.73 at the 0.60 FDG threshold,P<0.05 vs201T1 reinjection). In all circumstances, MIHA was less specific than201T1 reinjection for the detection of metabolic viability. In conclusion, in patients with recent myocardial infarction, MIHA
accurately detects the persistence of metabolic viability, but is not superior to201T1. 相似文献
43.
I. V. Smirnov A. A. Khachatur'yan 《Bulletin of experimental biology and medicine》1991,112(5):1601-1603
All-Union Hematology Research Center, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. I. Vorob'ev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 112, No. 11, pp. 500–501, November, 1991. 相似文献
44.
本实验建立了一种浮动基点式fura-2测定离体灌流心脏细胞内游离钙浓度的新模型,本模型中游动基点式测定地克服目前fura-2技术中受细胞内某些物质产生的自身荧光变化干扰的缺点,实现了自动消除细胞自身荧光变化对实验结果的影响,并在此基础上将广泛用于测定游离状态的细胞内游离钙的tura-2技术推广到离体灌流心脏,实现了在更接近心肌生理状态的条件下测定其胞浆游离钙。 相似文献
45.
Despite improvements in supportive care, the mortality and morbidity of asthma remain constant. The risks and incidence of morbidity related to barotrauma remain high in patients that require mechanical ventilation. The authors present three alternative strategies including the inhalation of anaesthetic agents, helium/oxygen ventilation, and extracorporeal membrane oxygenation which may be beneficial when 'conventional therapies' fail in the intubated patient with status asthmaticus. 相似文献
46.
子宫内膜异位症是育龄妇女的常见疾病 ,近年来其发病率有上升趋势 ,研究认为EM发生发展与腹腔氧化作用有关。氧化作用是一种炎症反应 ,EM中巨噬细胞释放的氧化活性物 ,腹腔液中氧化低密度脂蛋白及其产物的增加 ,子宫内膜细胞氧化酶与抗氧化酶的异常表达 ,腹腔液中VitE的消耗 ,均说明EM与腹腔氧化作用有关。本文综述有关研究结果为用抗氧化剂和抗炎症制剂预防EM发生提供新的研究途径 相似文献
47.
Preoperative metoprolol improves cardiovascular stability and reduces oxygen consumption after thoracotomy 总被引:1,自引:0,他引:1
C.–J. JAKOBSEN S. BILLE P. AHLBURG L. RYBRO K. D. PEDERSEN B. RASMUSSEN 《Acta anaesthesiologica Scandinavica》1997,41(10):1324-1330
Background : Increased sympathetic activity perioperatively and associated cardiovascular effects play a central role in cardiovascular complications. High thoracic epidural blockade attenuates the sympathetic response, but even with complete pain relief, haemodynamic and endocrine responses are still present. Beta–adrenoceptor blockade is effective in situations with increased sympathetic activity. This study was designed to evaluate the perioperative haemodynamic effect of preoperative βblockade and its influence on the haemodynamic aspects of the surgical stress response.
Methods : Thirty–six otherwise healthy patients undergoing elective thoracotomy for lung resection were randomised doubleblinded to receive either 100 mg metoprolol or placebo preoperatively. Anaesthesia was combined high thoracic epidural block and general anaesthesia. The epidural analgesia was continued during recovery. Patients were monitored with ECG, pulse oximetry, invasive haemodynamic monitoring, arterial blood gases and electrolytes.
Results : After induction of anaesthesia the mean arterial pressure (MAP) decreased in both groups, and decreased further in the placebo group after initiation of the epidural block. The heart rate (HR) was slightly less throughout the observation period after metoprolol. Peroperatively, the only difference in measured haemodynamics was a marginally higher MAP after metoprolol. Postoperative cardiac index (CI) was lower with a lower variability and cardiac filling pressures were slightly higher in the metoprolol group. The oxygen consumption index was higher after placebo throughout the observation period, with no difference in the oxygen delivery.
Conclusion. We found that preoperative β–blockade during combined general anaesthesia and high thoracic epidural blockade stabilised perioperative HR and CI and decreased total oxygen consumption. 相似文献
Methods : Thirty–six otherwise healthy patients undergoing elective thoracotomy for lung resection were randomised doubleblinded to receive either 100 mg metoprolol or placebo preoperatively. Anaesthesia was combined high thoracic epidural block and general anaesthesia. The epidural analgesia was continued during recovery. Patients were monitored with ECG, pulse oximetry, invasive haemodynamic monitoring, arterial blood gases and electrolytes.
Results : After induction of anaesthesia the mean arterial pressure (MAP) decreased in both groups, and decreased further in the placebo group after initiation of the epidural block. The heart rate (HR) was slightly less throughout the observation period after metoprolol. Peroperatively, the only difference in measured haemodynamics was a marginally higher MAP after metoprolol. Postoperative cardiac index (CI) was lower with a lower variability and cardiac filling pressures were slightly higher in the metoprolol group. The oxygen consumption index was higher after placebo throughout the observation period, with no difference in the oxygen delivery.
Conclusion. We found that preoperative β–blockade during combined general anaesthesia and high thoracic epidural blockade stabilised perioperative HR and CI and decreased total oxygen consumption. 相似文献
48.
人精子穿卵改良试验对不同生育状态男子生育力测定的价值 总被引:2,自引:0,他引:2
目的 本研究用一种经改良的人精子穿卵试验 (SPA)处理人精子 ,以探讨一种更简便、快速、经济 ,适合一般实验室要求的方法。方法 将精子体外获能液用磷酸氢二钠把pH值调理至 8.2± 0 .2 ;用普通隔水式恒温培养箱进行培养 ;对 75例不同生育状态男子生育力进行测定 (其中 2 5例有生育力男子 ;2 5例“原因不明”不育男子 ;及 2 5例输精管吻合术后 )。结果 3种不同生育状态男子的SPA值分别是 (4 7.12± 9.92 ) % ;(2 1.73± 9.91) % ,及 (2 8.0 4± 9.91) %。前两者在统计学上有显著差异 ,(P<0 .0 1) ;后两者在统计学上无明显差异 (P >0 .0 5 )。结果表明经用改良的精子获能液并在普通恒温培养箱培养后精子的活率和活力都有较大的提高 ,这有利于精子的长期获能及提高精子的穿透能力。结论 本研究提示改良后的人精子穿卵试验处理精子确实更简便、快速、经济 ,适合一般实验室要求 ,便于推广。 相似文献
49.
Ronald G. Pratt Jie Zheng Brent K. Stewart Yoseph Shiferaw Anthony J. McGoron Ranasinghage C. Samaratunga Stephen R. Thomas 《Magnetic resonance in medicine》1997,37(2):307-313
A limited flip angle gradient-echo 3D volume acquisition imaging protocol for mapping partial pressure of oxygen (pO2) in perfluorocarbon compounds (PFCs) at low field (0.14 T) is presented. The pO2 measurement method is based on the paramagnetic effect of dissolved molecular oxygen (O2) which reduces the PFC 19F T1? Specific objectives related to imaging of PFCs through use of the protocol include improved image signal-to-noise characteristics and elimination of 19F chemical shift artifacts. A parametric Wiener deconvolution filtering algorithm is used for suppression of 19F chemical shift artifacts. Application of the protocol is illustrated in a series of calculated pO2 maps of a gas equilibrated, multi-chamber phantom containing perfluorotributylamine (FC-43). The utility of the protocol is demonstrated in vivo through images of a commercially available perfluorocarbon based blood substitute emulsion containing FC-43 sequestered in the liver and spleen of a rat. 相似文献
50.
目的:观察高压氧结合针灸治疗脑外伤患者的疗效。方法:对96例脑外伤患者采用高压氧、针灸配合药物进行综合治疗。同时,对83例对照组患者根据病情给予降颅压、抗感染、改善脑供血、保护脑细胞等治疗,有手术指征者行清除血肿、减压和清创术。结果:出院时两组患者功能比较,治疗组明显优于对照组,有显著性差异(P<0.O1),疗效治疗组也明显好于对照组。结论:高压氧结合针灸治疗能够明显提高脑损伤患者疗效,对肢体功能有明显提高。 相似文献