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151.
本实验采用单细胞外记录神经元单位放电的方法,在Wistar大鼠上观察到网状巨细胞核。一区伤害性神经元57个,其中伤害兴奋性神经元(NEN)42个,伤害抑制性神经元(NIN)15个。电刺激黑质对NEN(29)和NIN(8的放电呈抑制作用,其反应百分率分别由刺激黑质第1分钟时的1.0±2.1%和-20.4±6.2%,降到第5分钟时的-83.6±12.3%和-65.4±10.7%(P<0.01)。刺激黑质对少数NEN(13)和NIN(7)的放电有兴奋作用,其值分别由第]分钟时的20.5±7.3%和1.0±3.4%,升高到第5分钟时的74.5±10.7%和21,5±8.6%(P<0.05)。氟哌啶醇注入PAG腹外侧部可阻断刺激黑质的效应,这提示从黑质到网状巨细胞核α-区存在着一条痛调制通路,而且这种通路的递质是多巴胺能的。  相似文献   
152.
153.
Background: Open exploration and endoscopic sphincterotomy (ES) remain the preferred treatment of common bile duct stones (CBDS). The recent spread of laparoscopy has worsened the dilemna of choosing between surgical and endoscopic treatment of CBDS. The aim of this study was to critically evaluate the results of our preliminary experience with laparoscopic common bile duct exploration (CBDE) for CBDS. Methods: Ninety-two consecutive patients were prospectively submitted to laparoscopic CBDE. Surgical strategy included an initial transcystic approach or laparoscopic choledochotomy. Failure of stone clearance was managed by conversion to open CBDE or by postoperative ES. Electrohydraulic lithotripsy and papillary balloon dilatation were selectively used. Stone clearance was assessed by choledochoscopy and control cholangiography. Results: The overall laparoscopic stone clearance in this series was 84% (transcystic route 63% and choledochotomy 93%). Conversion to laparotomy was mandatory in 12% of the patients because of incomplete stone clearance and in 5% because of intraoperative complications. Postoperative ES was required in 4% of the patients, giving an overall surgical success rate of 96%. When indicated (small and limited number of stones located below the cysticocholedochal junction, with a dilated and patent cystic duct) the transcystic route had the lower success rate, the higher complication rate, and the shorter operative time and postoperative hospital stay. When indicated (accessible and dilated common bile duct over 7 mm), laparoscopic choledochotomy had the higher success rate, the lower complication rate, the longer operative time, and the longer postoperative hospital stay, which is related to associated external biliary drainage. The hospital mortality included two high-risk patients (2%) and the complications rate was 15%. Conclusions: Laparoscopic CBDE is safe in selected patients. A stratified intraoperative surgical strategy is mandatory in deciding between a transcystic route and choledochotomy with specific indications for each approach. When feasible, laparoscopic choledochotomy is more efficient and safe than the transcystic route, but it is associated with a longer postoperative hospital stay, which is due to external biliary drainage. Received: 7 May 1996/Accepted: 19 November 1996  相似文献   
154.
Background: Laparoscopic stapling was found to be a viable option for attaching epimysial electrodes onto the abdominal surface of the diaphragm. Stapling was preferable to suturing due to its simplicity and speed. Methods: Of the two staplers tested in this study, the Ethicon Endopath was preferred over the Autosuture Endo Hernia because the staples did not penetrate the diaphragm when an electrode tab thickness greater than 0.75 mm was used. Results: The thickness of the electrode tab was an important factor in determining staple penetration but large variation in penetration depth indicated that other factors may also play a role. An electrode tab thickness of 1.0–1.25 mm was suggested to minimize the risk of diaphragm perforation. Conclusions: The histological reaction to staples implanted up to 14 months was unremarkable, reflecting the safety of laparoscopic staples for permanently anchoring electrodes on the diaphragm. Received: 2 April 1996/Accepted: 12 June 1996  相似文献   
155.
凝血机制紊乱在SIRS发展中的作用   总被引:2,自引:0,他引:2  
凝血机制紊乱在全身炎症反应综合症(SIRS)发展、恶化过程中起重要作用.对SIRS时凝血系统紊乱的形成机制、在SIRS发生发展过程中的作用及其对病情危重程度的预测价值作一综述.  相似文献   
156.
Leningrad University. (Presented by Academician of the Academy of Medical Sciences of the USSR S. N. Golikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 111, No. 5, pp. 458–460, May, 1991.  相似文献   
157.
目的:评估全肠外营养(TPN)对老年晚期消化系统恶性肿瘤病人生存期的影响。方法:回顾性分析121例老年晚期消化系统恶性肿瘤病人TPN治疗后的生存期。结果:TPN治疗后,患者生存期不同程度延长,为9~126天,平均68.1天,多数在两月左右。结论:TPN可延长老年晚期消化系统恶性肿瘤病人的生存期。  相似文献   
158.
Summary Single unit activity of 355 cells was recorded in the auditory thalamus of anesthetized cats before, during, and after the inactivation by cooling of the ipsilateral primary auditory cortex (AI). Most of the units (n = 288) showed similar functional characteristics of firing before and after the cryogenic blockade of AI. The spontaneous firing rate remained unchanged by cooling in 20% of the units and decreased in the majority of them (60%). In some regions, i.e. dorsal division of the medial geniculate body (MGB), lateral part of the posterior group of the thalamus, and auditory sector of the reticular nucleus of the thalamus, the maximum firing rate evoked by white noise bursts was generally affected by cooling in the same direction and to the same extent as the spontaneous activity. Units in the ventral division of MGB showed a characteristic increase of signal-to-noise ratio during cortical cooling. The corticofugal modulation led to the appearance or disappearance of the best frequency of tuning in 51 units and changed it by more than 0.5 octave in 34 units. The bandwidths of different response patterns to pure tones stimulation were used to define a set of functional properties. During cryogenic blockade of AI, two cortically modulated sub-populations of units were usually distinguished that exhibited changes for a given functional property. The complexity and diversity of the effects of cortical inactivation suggest that the corticothalamic projection may be the support for selective operations such as an adaptive filtering of the incoming acoustic signal at the thalamic level adjusted as a function of cortical activity.  相似文献   
159.
青黛颗粒抗炎、镇痛作用的实验研究   总被引:3,自引:0,他引:3  
目的 :通过对青黛颗粒抗炎、镇痛作用的实验研究 ,探讨该药治疗溃疡性结肠炎的作用机理。方法 :采用小鼠醋酸扭体法、大鼠棉球肉芽肿法和角叉菜胶所致大鼠足肿胀方法。结果 :青黛颗粒给药高、中、低剂量组和阳性对照药组均明显降低小鼠扭体次数 (P<0 .0 5~P<0 .0 1)。对大鼠棉球肉芽肿和大鼠足肿胀有显著的抑制作用 (P <0 .0 1~P <0 .0 0 1)。结论 :青黛颗粒分别对大鼠具有抗炎、对小鼠具有镇痛作用。且镇痛作用呈量效关系  相似文献   
160.
Tuberculous infection among children continues to be a significant cause of morbidity. The symptom complex are so variable among children that the final diagnosis often rests on the laboratory tests. Proper interpretation of the tests, specially tuberculin test and radiographic studies, are necessary for establishing correct diagnosis. The usefulness of tuberculin test in both unimmunized and BCG vaccinated children is highlighted. BCG accelerated response as a test should be reserved for identifying serious form of pulmonary disease or CNS tuberculosis when the tuberculin test is negative. Radiographic assessment may be sensitive in some instances but not always specific and hence needs cautious interpretation. Tuberculosis among BCG vaccinated children though not uncommon, needs proper documentation. Current trends in the management of tuberculosis including CNS forms are briefly outlined.  相似文献   
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