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91.
We analyzed performance and efficiency of the left ventricular myocardium on the basis of two new energetic parameters. The myocardial energy consumed during one cardiac cycle is related to performed work on the one hand (E1) and to the stress-time-integral on the other (E2). E1 was obtained by analysis of the pressure-volume integral divided by left ventricular muscle mass. E2 was obtained as follows: the stress-time integral was analyzed from pressure-volume data and wall thickness using an ellipsoidal calculation model. In order to transfer the stress-time integral into energy units, the value was multiplied by a constant factor which was obtained in experimental myothermal studies. In ten patients with coronary heart disease undergoing diagnostic heart catheterization, angiocardiography was performed before and after oral administration of nitroglycerin (1.6 mg). Total energy consumption (2E1 + E2) per gram myocardium per beat decreased from 6.1 +/- 1.3 mcal/g to 4.7 +/- 1.4 mcal/g (P less than 0.01), and myocardial efficiency (E1/[2E1 + E2]) increased from 27.0 +/- 3.1% to 28.4 +/- 4.3% (N.S.) on the average. This analysis explains quantitatively the beneficial effect of nitro-preparations on myocardial function and energetics.  相似文献   
92.
本文对1984年1~3月和1985年3~8月共107例急性下呼吸道感染的住院患儿,采用间接免疫荧光法检测其急性期血清抗RSV特异性IgM抗体,并与病毒分离和/或中和试验比较,敏感性为82.1%,特异性为71.8%。RSV感染患儿发病后3天内大多数病例即可从血清中检测出RSV-IgM,因此该法具有早期诊断价值。  相似文献   
93.
Type IIIC tibial fractures are complex injuries involving extensive bone and soft-tissue devascularization that result in a high percentage of complications and ultimate amputation. An emergency free flap transfer not only may salvage the limb but also may improve the aesthetic and functional results of reconstruction by placing the injured structures in a well-vascularized bed. Two cases of type IIIC tibial fracture were treated in this manner, and we present our experience with a 30-month follow-up of one patient and a 6-month follow-up of another patient.  相似文献   
94.
Prolongation of the action potential duration of dorsal root ganglion (DRG) neurons by low (nM) concentrations of opioids occurs through activation of excitatory opioid receptors that are positively coupled via Gs regulatory protein to adenylate cyclase. Previous results suggested GM1 ganglioside to have an essential role in regulating this excitatory response, but not the inhibitory (APD-shortening) response to higher (μM) opioid concentrations. Furthermore, it was proposed that synthesis of GM1 is upregulated by prolonged activation of excitatory opioid receptor functions. To explore this possibility we have utilized cultures of hybrid F11 cells to carry out closely correlated electrophysiological and biochemical analyses of the effects of chronic opioid treatment on a homogeneous population of clonal cells which express many functions characteristic of DRG neurons. We show that chronic opioid exposure of F11 cells does, in fact, result in elevated levels of GM1 as well as cyclic adenosine monophosphate (AMP), concomitant with the onset of opioid excitatory supersensitivity as manifested by naloxone-evoked decreases in voltage-dependent membrane K+ currents. Such elevation of GM1 would be expected to enhance the efficacy of excitatory opioid receptor activation of the Gs/adenylate cyclase/cyclic AMP system, thereby providing a positive feedback mechanism that may account for the remarkable supersensitivity of chronic opioid-treated neurons to the excitatory effects of opioid agonists as well as antagonists. These in vitro findings may provide novel insights into the mechanisms underlying naloxone-precipitated withdrawal syndromes and opioid-induced hyperalgesia after chronic opiatf addiction in vivo. © 1995 Wiley-Liss, Inc.  相似文献   
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Mingying  Lai  Ningli  Wang 《眼科学报》1997,13(3):116-119
Purpose : To compare the clinical application value of Ultrasound biomicrsocpic dark room provocative test with the traditional dark room test in screening primary angle closure glaucoma (PACG).Methods: 22 eyes with PACG in prodromal stage and 30 eyes with deep anterior chamber and wide angle of 15 normal persons were observed in this trail. All 52 eyes were performed traditional dark room provocative test and ultrasound biomicorosopic darkroom test respectively. With different positive diagnostic criteria, the sensitivity of the two methods were compared using chi-squared analysis.Results : After staying in the dark room for 2 hours, In case group, IOP in 10 of 22 eyes rose more than 1. 07kPa(1kPa = 7.5mmHg), in 12 eyes less than 1.07kPa or had no changes; appositional angle closure were found by Goldmann gonioscopy in 8 eyes : 3 eyes in two quadrants, 5 eyes in more than two quadrants; the appositional angle closure was found by UBM in 15 eyes; 3 eyes in one quadrants, 5 eyes in two quadrants, 7 eyes  相似文献   
98.
教育在以病人为中心整体护理中的作用   总被引:1,自引:0,他引:1  
以病人为中心的整体护理是当代护理科学发展的必然趋势。为了适应这一形势,必须充分发挥教育在整体护理中的作用,进行护理教育的改革。改革传统中专护理教育体制,延长学制,增设有关课程;强化护理人员全日制教育;加强护理人员思想政治、职业道德和敬业精神教育,在护理人员中增强整体护理观念,以适应医学模式的转变。  相似文献   
99.
神经肽Y(NPY)是广泛分布于中枢神经系统和外周神经各部位的神经肽类物质。本实验观察NPY在体外对几种免疫细胞活性的直接作用。结果表明,NPY对小鼠T淋巴细胞丝裂原反应性和NK细胞的杀伤活性均无明显影响(P>0.05),对巨噬细胞分泌溶菌酶有明显抑制作用(P<0.05);而对B淋巴细胞丝裂原反应性则有明显的促进作用(P<0.05)。上述结果提示,NPY对部分免疫细胞功能的影响因细胞种类而异。  相似文献   
100.
The MR imaging features of a paraganglioma of the cauda equina with associated spinal cord cysts are presented. MR imaging showed the tumor to be isointense with the spinal cord on all pulse sequences and to enhance homogeneously. The intramedullary cysts had increased signal intensity on proton density- and T2-weighted images, and involved the cervical and thoracic regions.  相似文献   
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