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21.
Y Goto  W Taki  H Kikuchi 《Brain and nerve》1988,40(11):1045-1049
Using the four-vessel extracranial one staged occlusion model of adult Wistar rats, we analyzed quantitatively released free fatty acids during ischemia. Also have we analyzed the effect of bifemelane to reduce free fatty acid accumulation after the onset of ischemia. Bifemelane (15 mg/kg, 30 mg/kg) and saline as control were intraperitoneally administered to adult Wistar rat prior to 30 minutes of experimentally induced ischemia. The results obtained were analyzed by one or two way analysis of variance (ANOVA). Physiological variables (systemic arterial pressure, PaO2, PaCO2, pH) did not change significantly in all four experimental groups. Total free fatty acid levels (sum of 5 fatty acid) increased significantly after ischemia (30 minutes). Higher dose (30 mg/kg) of bifemelane administration significantly reduced total free fatty acid accumulation, though lower dose (15 mg/kg) did have no effect. Bifemelane (30 mg/kg) reduced significant accumulation in the amount of saturated and monounsaturated fatty acid (palmitic acid [16:0], stearic acid [18:0] and oleic acid [18:1]). Arachidonic (20:4) and docosahexaenoic (22:6) acid failed to show any effective reduction by bifemelane pre-treatment of lower nor higher dose. Bifemelane is supposed to have many pharmacological effects such as increase in cerebral blood flow, augmentation of glucose uptake, monoamine metabolism, cerebral vasodilatation and platelet antiaggregation. Free fatty acid accumulation is effectively suppressed by the higher dose of bifemelane administration. Although the exact mechanism are not clearly identified by the result obtained in this experiment, selective inhibition of accumulation in saturated and monounsaturated fatty acids by bifemelane pretreatment may be obtained by the improvement of energy metabolism, which may help to reacylation of fatty acid into phospholipid.  相似文献   
22.
Lumbar subarachnoid pressure (LSP) was continuously monitored via intrathecally introduced polyethylene catheter to select the patients for shunt operation. A total of seventy cases included so-called normal pressure hydrocephalus (NPH) secondary to subarachnoid hemorrhage (SAH; 34 cases), idiopathic NPH (17 cases), secondary NPH whose symptoms developed after operations for brain tumors, head injuries or meningitis (12 cases) and other intracranial diseases including pseudotumor cerebri or meningeal carcinomatosis, etc. (7 cases). Shunt operation was effective in 36 cases and not effective in 9 cases, while 25 cases were not shunted since LSP was not elevated or clinical manifestations were slight. Mean values of baseline pressure and maximum pressure in shunt effective group, shunt non-effective group and non-shunted group were 14.5, 12.7, 9.0 and 29.9, 25.0, 17.9 mmHg, respectively. Statistical difference was observed between shunt effective group and non-shunted group. Frequency of pressure waves was also significantly higher in shunt effective group than in non-shunted group. Above all, measurement of LSP was regarded as useful in idiopathic NPH. However, preoperative clinical symptoms had a closer relationship to shunt response than results of LSP in post SAH patients. Complication related to this monitoring was negligible except in one case of meningitis which was easily treated by administration of antibiotics. Follow-up study also justified our selection since no further deterioration was noted in non-shunted group. The present study indicates that measurement of LSP would be useful in selecting the patients who will benefit from shunting and in eliminating unnecessary shunt operations because this simple method is easily performed at bed side without perforating the skull.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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24.
Off-pump coronary artery bypass grafting has become an attractive surgical alternative for myocar-dial revascularization because of the advantage of myocardial protection and other benefits of patients. However, it is still regarded as a controversial treatment for the coronary artery disease accompanied by atrial fibrillation (AF). A significant number of patients in need of coronary revascularization have chronic AF. Although the Cox-Maze III procedure is the gold standard for the surgical treatment of AF, few of these patients undergo AF operations at the time of their coronary bypass grafting. We report herein a case of the pulmonary vein isolation to eliminate the AF by means of epicardial radiofrequency ablation combined with 2 vessels coronary artery bypass grafting on the beating heart with the aid of cardiopulmonary bypass.  相似文献   
25.
26.
C Kim  H Kikuchi  N Hashimoto  F Hazama 《Neurosurgery》1990,27(5):715-9; discussion 719-20
Five cynomolgus monkeys treated with unilateral carotid ligation, renal hypertension, and beta-aminopropionitrile feeding were studied repeatedly by cerebral angiography to clarify the growth process of saccular cerebral aneurysms. Repeated angiography demonstrated saccular cerebral aneurysms in three of five monkeys; two aneurysms were found 15 months and a third 12 months after the operation. At autopsy, one saccular aneurysm was found to be bilocular in shape, and the others were unilocular. Fusiform aneurysms were also observed in four monkeys. Microscopic studies revealed the walls of the saccular aneurysms were very thin and consisted of fibrous tissue. In one aneurysm, the aneurysmal sac was almost obstructed by a well-organized thrombus. No evidence of intramural hemorrhage was found in any of the saccular cerebral aneurysms. The conversion of early aneurysmal changes into saccular aneurysms was found to occur abruptly, and no consistent growth rate was noted. The multiloculation of saccular aneurysms was closely related to the size of an aneurysm. The present study indicates that a saccular cerebral aneurysm may grow abruptly from one of several different kinds of early aneurysmal changes.  相似文献   
27.
We herein report the case of a 53-year-old man with a nonspecific acute colonic ulcer whose liver function deteriorated after he had undergone hepatectomy. He was referred to our hospital for a hepatoma caused by hepatitis B virus and a right hemihepatectomy was performed. His liver function was poor after the operation, and minor complications such as pleural effusion and biliary fistula developed. A large amount of melena was seen 29 days after the hepatectomy and he developed hemorrhagic shock. Superior mesenteric arteriography revealed pooling of blood in both the hepatic flexure of the ascending colon and the cecum. An emergency right hemicolectomy was performed. There was a 5 x 1-mm ulcer 18 cm distal to the ileocecal valve. Numerous erosions were observed to be scattered throughout the colonic mucosa. The patient recovered slowly and was discharged 6 months after the hepatectomy. This is the first report of an acute colonic ulcer that could have been caused by liver dysfunction.  相似文献   
28.
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   
29.
A 6 month-old male infant (weight: 4.5 kg) with congenital aortic stenosis underwent aortic valve replacement with a pulmonary autograft (Ross procedure). The right ventricular outflow tract (RVOT) was reconstructed with a polytetrafluoroethylene (PTFE)-valved equine pericardial conduit. At the age of 5, re-RVOT reconstruction with an equine pericardial patch bearing a PTFE monocusp was required because of severe pulmonary stenosis resistant to 2 attempts of percutaneous transluminal pulmonary valvotomy. Currently, at the age of 8, the degree of aortic regurgitation is trivial and the pulmonary autograft is free of functional deterioration despite somatic growth.  相似文献   
30.
The CT findings of 19 children under 16 years of age with primary brain tumors in the cerebral hemisphere were investigated with special reference to the existence of cerebral hemiatrophy ipsilateral to the side of the tumor. "Ipsilateral cerebral hemiatrophy" was observed in four of 19 cases (21%). These included two cases with germinoma in the basal ganglia and two with low-grade astrocytoma in the frontal and occipital cortex. This peculiar CT finding was not specific to the location or histology of the tumor. The four cases were characterized by slow progression, which contrasted with the rapid progression of tumors shown in seven cases with a mass effect on CT.  相似文献   
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