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991.
目的:研究依那普利(Ena)对豚鼠乳头状肌电生理特性,哇巴因诱发的延迟后除极(DAD)和触发电活动(TA)的直接作用方法与结果,采用标准玻璃微电极技术记录豚鼠乳头状肌动作电位,Ena呈浓度依赖性增加静息膜电位(RP)和动作电位幅度(APA),而对0期最大除极,超射,和动作电位时程无明显影响Ena10μmol.L^-1则可明显抑制哇巴因0.5μmol.L^-1则可明显抑制哇巴因0.5μmol.L^-  相似文献   
992.
There is a large body of literature describing the causative role of oxidative stress mediated by increased levels of reactive oxygen species in the pathogenesis of cardiovascular disease such as atherosclerosis, hypertension, and restenosis after angioplasty. The positioning of a soft silicone collar around the rabbit carotid artery elicits intimal thickening. The findings from recent studies demonstrated that both intimal thickening and atherosclerosis lead to synthesis of inducible nitric oxide synthase, resulting in abundant amounts of nitric oxide. We investigated the effects of collaring and nicardipine treatment on the activities of antioxidant enzymes, superoxide dismutase and catalase, and total nitrite/nitrate levels, stable products of nitric oxide. Placing the collar increased the total nitrite/ nitrate levels and decreased superoxide dismutase activity in collared arteries. Treatment with nicardipine (20 mg/kg/day, s.c.) prevented enhanced nitric oxide degradation without affecting superoxide dismutase and catalase activities. Our results suggest that enhanced nitric oxide production and superoxide anion are generated in response to the collaring, resulting in oxidative stress within the segment in this model.  相似文献   
993.
目的引入动态的图象测里概念,进行口周软组织移动量的测量。方洁利用已开发的计算机图象处理系统.对三种测定条件下口腔周围软组织的移动量进行测量研究。结果(1)发/mo/时,口唇突出,上唇的测定点向上内前方.下唇的测定点向下内前方动作,因此.唇上三角形面积变化的大小依次为M3相似文献   
994.
995.
We report anesthetic management of a 20-year-old male patient with cerebral palsy who underwent an operation for retinal detachment of the left eye. Induction and maintenance of anesthesia were smoothly done with inhalation of 1-5% sevoflurane with nitrous oxide and oxygen. Emergence of anesthesia was also smooth except for slight and transient excitement. Anesthetic management of a patient with cerebral palsy was also discussed.  相似文献   
996.
To elucidate the effect of jaundice on the electrophysiological characteristics of the gastric mucosa and gastric acid secretion, gastric mucosal potential difference (PD) and gastric acid secretion were measured in rats with obstructive jaundice. Also transepithelial potential difference (TEPD), short circuit current (Isc) and transepithelial electrical resistance (Rt) were measured in the isolated gastric mucosa of rats with obstructive jaundice. Secondly, to confirm whether the alteration of these parameters were induced by jaundice and increased serum bile acids in the jaundiced rats, the effects of biliary drainage on the electrophysiological characteristics and gastric acid secretion, and the effects of bile acid (TCA) on TEPD, Isc, Rt were evaluated. PD, TEPD, Isc and gastric acid secretion were reduced in the jaundiced rats, and tended to recover after biliary drainage. TEPD and Isc were reduced significantly by TCA administration. These results suggest that active ion transport in the gastric mucosal cells and gastric acid secretion are impaired in jaundiced rats and the increased serum bile acid in jaundiced rats may cause these dysfunctions and the impaired active ionic transport function is improved by biliary drainage.  相似文献   
997.
998.
Coronary artery bypass grafting with combined arterial graft using the left internal mammary artery (IMA), right IMA, and the right gastroepiploic artery (GEA) was performed in 45 patients with saphenous vein graft (SVG) (29 patients) or without SVG (16 patients) from February 1989 to October 1989. The left IMA was used in all patients, the right IMA was used in 9 patients, and the GEA was used in 43 patients. Perioperative myocardial infarction was noted in two patients who had hospital deaths. Reopening the chest for postoperative bleeding was performed in two patients, and the cerebral accident was noted in one patient. Fourteen patients were operated on without the requirement for blood transfusion. Studied within 3 postoperative months, all arterial grafts were patent though the patency was 97.7% (43/44) in SVG. It is concluded that the combined arterial graft utilizing the IMAs and GEA can be used safely and effectively.  相似文献   
999.
We compared midazolam 0.2 mg.kg-1 and fentanyl 50 micrograms with thiamylal 4 mg.kg-1 for rapid sequence induction. We could use midazolam safely in patients with bronchial asthma or drug allergy. There was no difference in time from the beginning of induction to intubation between midazolam treated group and thiamylal treated group. Changes in systolic as well as diastolic blood pressure and heart rate during 2 hours from intubation were smaller in midazolam treated group than in thiamylal treated group. In midazolam treated group, no arrhythmias were observed at the time of intubation. We could reduce the amount of anesthetics in midazolam treated group during 2 hours from intubation. From the results mentioned above, we conclude that midazolam is a useful agent for rapid sequence induction.  相似文献   
1000.
The synthesis of DNA, RNA, and protein by varicocele testes with spermatogenic dysfunction was studied by examination of the levels of incorporation of [3H]thymidine, [14C]uridine, and [14C]leucine into the testicular tissue at 31 degrees C in vitro. The results suggest that DNA synthesis by the testis with moderate tubular damage is impaired whereas synthesis of RNA and protein is not. The cell regenerative ability of the testis with moderate tubular damage may be poor in spite of the preservation of testicular cell RNA and protein synthesis.  相似文献   
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