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81.
Summary A new double sucrose gap chamber using electrodes of high stability and low resistance is described. The size of each sucrose gap and the central node can be modified independently so that this chamber is suitable for research on multicellular or unicellular excitable preparation under voltage clamp conditions. The shape of the central channel is made so as to reduce the series resistance between the preparation and the recording electrode to a minimum. A window made in the floor of the chamber allows to observe the preparation under a microscope.This work was performed under the I.N.S.E.R.M. grant no. 17.75.40. 相似文献
82.
目的探讨肾静脉平面以上结扎大鼠下腔静脉后的心、肾功能及肾脏病理改变。方法在肾静脉平面以上结扎大鼠下腔静脉,术后1,6,24,48h检测心率、射血分数、心输出量、每搏输出量、鼠尾动脉压等心脏血流动力学指标。术后6h、12h、24h、2d、3d、4d、5d、7d检测血肌酐、尿素氮、24h尿量及N-乙酰-β-D-氨基葡萄糖苷(NAG)酶并观察肾脏病理改变。结果肾静脉平面以上结扎大鼠下腔静脉后心输出量减少、血压下降,但至术后48h可完全代偿。术后血肌酐、尿素氮、尿NAG酶升高,肾脏瘀血并见大量管型;术后第3天,肾脏恢复正常结构;术后第4天,血肌酐、尿素氮恢复正常;术后第5天,尿NAG酶恢复正常。所有动物均存活。结论肾静脉平面以上结扎大鼠下腔静脉,可因回心血量急骤减少和双肾瘀血而影响心、肾功能。但心功能术后48h即可完全代偿。肾功能术后第5天即可完全代偿。建议当腹膜后肿瘤侵及肾静脉以上段下腔静脉时,可在切除肿瘤及累及下腔静脉段后,直接结扎下腔静脉残端,不必附加切除右肾。术后早期应注意经上肢浅静脉补充液体以增加回心血量。 相似文献
83.
84.
目的 观察应用尼卡地平预防双腔支气管导管插管心血管反应的效果。 方法 肺、食道择期手术病人 40例 ,随机分为 2组 ,每组 2 0例。咪唑安定 0 .0 4mg/kg、异丙酚 1.5mg/kg、芬太尼 4μg/kg、维库溴铵 0 .12mg/kg静脉诱导后 ,甲组给予尼卡地平 4μg/kg ,乙组给予生理盐水 3ml作为对照。分别于诱导前、后 ,插管后即刻及 1、3、5min监测收缩压 (SBP)、舒张压 (DBP)、心率 (HR) ,并计算心率收缩压乘积 (RPP)。 结果 A组插管后血压无明显升高 ,心率较诱导前无明显增快 ,B组插管后血压明显升高。 结论 尼卡地平可抑制双腔支气管导管插管时的心血管副反应。 相似文献
85.
目的:回顾58例双瓣替换术体外循环管理状况,总结双瓣替换术中灌注技术。方法:对58例风湿性心脏瓣膜病人施行二尖瓣、主动脉瓣替换术中体外循环手术的临床资料、心肺转汉方法和心肌保护中的难点及处理进行回顾总结分析。结果:58例中早期死亡2例,死亡率3.45%R。结论:只有良好的体外循环灌注技术和心肌保护,才能保证双瓣替换术病人顺利渡过围术期,降低手术死亡率。 相似文献
86.
87.
护理质量评价体系的改进及其软件开发 总被引:15,自引:1,他引:14
通过对《军队医院护理质量主要评价指标》在运用过程中存在不足之处的分析,结合实际对原评价体系的评价方法,评价内容进行了补充和完善,形成了一套既能从宏观上全面反映医院护理质量达标情况。又能从微观上具体反映各临床科室护理质量达标程度及名次排列的评价体系,使护理质量管理更具针对性。在此基础上又介绍了研制出的适合医院护理工作特点的《护理质量综合评价》软件。 相似文献
88.
Immunocytochemical Study of Cells in the Vitreous of Proliferative Virteoretretinopathy 总被引:1,自引:0,他引:1
Purpose: To identify the cellular components of vitreous samples obtained during vit-rectomy for proliferative vitreoretinopathy(PVR).Methods: With the use of three intermediate filament (IF) proteins, vimentin, glialfibrillary acidic protein (GFAP), and cytokeratin (CK), cytocentrifuge slides of 14fresh vitreous aspirates were detected with immunohistochemical technique.Results: All the specimens contained epithelial-like proliferative cells with or withoutpigment and some membrane-like pieces. Immunocytochemical staining showed that76.0-90.0% cells stained for CK, 17.4-29.6% cells expressed GFAP, and 80.1-91.0% cells were positive for vimentin.Conclusions : Majority of cells in the vitreous samples originated from retinal pigmentepithelial cells (RPE) and glial cells in PVR. Expression of IF proteins may be determinedby tissue of origin and local microenvironment. Eye Science 1999 ; 15; 13 - 16. 相似文献
89.
Jai H. Joshi Kathryn A. Newman Bary W. Brown Rebecca S. Finley Robert L. Ruxer Mark A. Moody Stephen C. Schimpff 《Supportive care in cancer》1993,1(4):186-194
In a prospective, randomized trial, 205 febrile episodes in granulocytopenic cancer patients were treated with ceftazidime with or without tobramycin (C±T), both agents being administered only if the initial granulocyte count was below 200/l, or ceftazidime plus piperacillin (C+P). The overall response rate was 71% (39 of 60 for C±T and 45 of 58 for C+P). Logistic regression analyses documented no evidence of a significant difference between the two regimens in overall treatment effect after accounting for the linear effects of potentially important variables, such as infection type and granulocyte count. Although the response rates for the subgroup of patients with bacteremias was better with the C+P regimen (P=0.06), there was no difference in response for patients with bacteremia and profound (<100/gml) sustained granulocytopenia. The double -lactam combination demonstrated in vitro synergism in 73%; antagonism was not seen. Both regimens produced execllent serum bactericidal levels (C±T geometric mean peak 1:170; C+P peak 1:137) against gram-negative but not gram-positive pathogens (1:4; 1:7 respectively) that had caused bacteremia. Emergence of resistance and significant coagulopathy and/or bleeding did not occur during therapy. Antibiotic-related nephrotoxicity was noted in 7 of 95 trials in the C+P and in 6 of 89 trials in the C±T group (P=0.19). The incidence of secondary infections in patients with profound (<100/l) sustained granulocytopenia was lower in the C±T group (P=0.04). Alimentary canal anaerobic flora preservation with C±T, and suppression with C+P, was demonstrated. These results suggest that these regimens are of similar effectiveness and neigher is associated with major toxicity. 相似文献
90.
K. Albus P. Wahle J. Lübke C. Matute 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1991,85(1):235-239
Summary The contribution of neurons containing -aminobutyric acid (GABA) to horizontal intrinsic projections in layers I–III of cat's striate cortex was investigated by combining GABA-immunohistochemistry with axonal tracing. After intracortical injections of Rhodamine-labelled latex microspheres Rhodamine-labelled neurons form patch- or bandlike aggregations (clusters) separated from each other by regions containing fewer, evenly distributed or no labelled neurons. Of the Rhodamine-labelled neurons about 5% display GABA-immunoreactive material (double labelled = DL-neurons). Approximately 70% of the DL-neurons occur at distances of less than 1 mm, and the remaining 30% at distances between 1 mm and 2.5 mm from the injection. About 60% of the DL-neurons reside within clusters and 40% are located in regions between clusters; the respective percentages of the Rhodamine labelled GABA-negative neurons are about 85 and 15. Considering their small number and their spatial distribution inhibitory interneurons seem to make only minor contributions to the clustered pattern of intrinsic connections. Our results demonstrate that the topographical organization of neurons giving origin to lateral inhibitory interactions in upper layers of cat's striate cortex is different from that of neurons mediating excitatory functions. 相似文献