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51.
去胆管及去门静脉肝叶肝细胞功能分化的研究 总被引:1,自引:1,他引:0
目的 观察胆管结扎及门静脉结扎后肝细胞形态及功能分化现象,探讨去胆管及去门静脉肝叶的保留价值.方法 应用氰基丙烯酸酯对仅保留两个肝叶的大鼠行一叶胆道栓塞并结扎,另一肝叶行门静脉结扎,进行分肝静脉血化验检查、组织病理及超微结构观察.结果 去胆管肝叶形态及糖原染色变化不大,分肝静脉血白蛋白(30.9±1.8)g/L与对照组(31.9±2.0)g/,L比较差异无统计学意义(P>0.05).去门脉肝叶萎缩明显,但血胆红素指标维持正常,与未处理对照组比较[(7.7±3.2)比(8.7±2.3)μmol/L]差异无统计学意义(P>0.05).结论 去胆管肝叶在观察期内无明显萎缩,仍保留有蛋白质合成分泌等功能;去门脉肝叶肝细胞能够承担胆汁代谢功能. 相似文献
52.
Takafumi Nagaoka Yoichi Katayama Toshikazu Kano Kazutaka Kobayashi Hideki Oshima Chikashi Fukaya Takamitsu Yamamoto 《Neuromodulation》2007,10(3):206-215
Objective. Employing [18F]fluorodeoxyglucose (FDG) positron emission tomography (PET) to assess the correlation between the effect of deep brain stimulation (DBS) on the subthalamic nucleus (STN) and the regional cerebral metabolic rate of glucose (rCMRGlc) in advanced Parkinson's disease patients (N = 8). Materials and Methods. On the basis of patients’ diary records, we performed FDG‐PET during the off‐period of motor activity with on‐ or off‐stimulation by STN‐DBS on separate days and analyzed the correlation between changes in motor symptoms and alterations in the rCMRGlc. Result. When FDG‐PET was performed, the motor score on the unified Parkinson's disease rating scale (UPDRS) was 64% lower with on‐stimulation than with off‐stimulation (p < 0.001, Wilcoxon single‐rank test). STN‐DBS increased the rCMRGlc in the posterior part of the right middle frontal gyrus, which corresponded to the premotor area, and the right anterior lobe of the cerebellum (p < 0.005, paired t‐test). No region exhibited a decrease in rCMRGlc. Among the items of the UPDRS motor score, the changes in resting tremor and rigidity of the left extremities showed a significant correlation with the changes in rCMRGlc observed in the right premotor area (p < 0.02 and p < 0.05, respectively, Spearman's rank correlation). Conclusions. STN‐DBS either activates the premotor area or normalizes the deactivation of the premotor area. These FDG‐PET findings obtained are consistent with the idea that STN‐DBS modifies the activities of neural circuits involved in motor control. 相似文献
53.
T. Sakaki T. Matsuyama T. Yabuno H. Hashimoto Sh Kurokawa Sh Kawaguchi T. Morimoto 《Acta neurochirurgica》1995,133(1-2):17-21
Summary The authors describe an approach through the temporal horn of the lateral ventricle which proved to be useful for clipping of a large dorsal type basilar bifurcation aneurysms. It facilitates the preservation of the perforating arteries behind the aneurysm, because it gives sufficient working space to move the aneurysm dome. Furthermore this approach avoids many of the disadvantages of other approaches, especially the risk of iatrogenic injuries of the Sylvian or Labe's vein. 相似文献
54.
Neural responses in the dorsal motor nucleus of the vagus (DMV) to topical administrations of sodium and portal infusions of hypertonic saline were investigated electrophysiologically by using multibarrel electrodes in anesthetized rats. Of 102 neurons that showed antidromic response to electrical stimulation of the ventral gastric vagus or the accessory celiac vagus, 51 neurons increased and 13 neurons decreased their discharge rates in response to the electrophoretic administration of sodium. The other 38 neurons did not respond to this stimulation. The portal infusion of hypertonic saline elicited neural responses of some DMV neurons whose axons are involved into either the ventral gastric or the accessory celiac vagus. Further, effects of the topical administration and the portal infusion of hypertonic saline were examined on 33 neurons. Typical response was characterized by an increase in discharge rate responding to both of the portal infusion and the topical administration. In conclusion, the DMV neurons receiving the afferent inputs from hepatoportal osmoreceptors may have an enteroceptor function detecting the change in osmotic pressure of their environment. 相似文献
55.
56.
通过对25例成人尸体的解剖学调查及应用"侧脑室─头静脉分流术"治疗23例梗阻性脑积水的临床疗效观察,旨在确立一种脑积水症手术分流的新途径。23例手术病人显效率92%(21/23)。18例(78%)基本恢复正常。3例(13%)明显好转。2例轻度改善。分析表明:头静脉具备位置浅表恒定、管径适宜、瓣膜可防止血液返流等解剖学特点。是一条可供选择的较为理想的脑积水症分流途径。 相似文献
57.
Kemal Gündüz Nazmİ Zengİn Süleyman Okudan Mehmet Okka Nİlgün Özbayrak 《Documenta ophthalmologica. Advances in ophthalmology》1995,91(2):155-164
We recorded pattern electroretinograms and visual evoked potentials in a group of selected patients with unilateral uncomplicated branch retinal vein occlusion. To document the effects of preexisting risk factors, patients were divided into three groups: diabetes mellitus, hypertension with hyperlipidemia and no systemic disease. The transient and steady-state pattern electroretinogram and visual evoked potential amplitudes were significantly reduced and visual evoked potential peak times were delayed relative to the fellow eyes and agematched normal subjects. There was a second amplitude reduction relative to the other patient groups in both the affected and fellow eyes of the diabetes mellitus group, which was indicative of an additive effect of diabetes mellitus.Abbreviations BRVO
branch retinal vein occlusion 相似文献
58.
Masahiro Tsuboi Hisao Asamura Tsuguo Naruke Haruhiko Nakayama Haruhiko Kondo Ryosuke Tsuchiya 《Surgery today》1997,27(11):1074-1076
A video-assisted right upper lobectomy was successfully performed on a 58-year-old man with an anomalnous segmental pulmonary
vein. The tumor was a peripherally located adenocarcinoma. The anomalous vein behind the right main bronchus was identified
and safely divided. This case emphasized that to perform this procedure successfully, (1) a careful preoperative evaluation
of the anatomy, including the presence of any possible vascular and/or bronchial anomalies, is necessary, and (2) if any anatomical
structures cannot be determined intraoperatively, a conversion into an open procedure must immediately be undertaken. 相似文献
59.
60.
High frequency electrical stimulation by means of electrodes implanted into the brain has become an accepted technique for treatment of Parkinson's disease. The electrical field distribution normally inserted into the sub thalamic nucleus minimise abnormal brain activity. Square wave pulses of 1–3.6 V with duration of 60–90 μs at a frequency range of 130–185 pps are generally used. Every electrode unit consists of four cylindrical electrodes positioned in a row and can be switched on independently. This paper determines the contact impedance of the electrodes for different frequencies and proposes improvement to reduce the contact impedance between the electrodes and the brain. Measurements were performed by placing the electrodes in a tank filled with saline. Different frequencies were applied on two electrodes via a resistor. The current was measured through the resistor and the voltage was registered between one of the electrodes and a third non current carrying electrode. The obtained values were used to calculate the contact impedance. The result shows large contact impedance for the used frequency compared to the impedance of the treated tissue, which means that variation in contact impedance can result in variation in the electrical field applied to the tissue. 相似文献