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91.
S Yanaura E Tagashira T Nagase T Izumi 《Nihon yakurigaku zasshi. Folia pharmacologica Japonica》1978,74(2):303-316
A single administration of ifenprodil at the doses of 100, 200 and 400 mg/kg (p.o.), and 50 and 100 mg/kg (i.m.) produced a moderate CNS depression in rats, such as, sedation, ptosis, systemic muscle relaxation and decrease in motor activity. These symptoms appeared dose-dependently and persisted for about 4 hours following administration. In a direct physical dependence test, 5 groups of rats were fed the ifenprodil-admixed food together with drinking water ad libitum for 24 hours daily for 53 approximately 103 days (mean ifenprodil intake, 43--240 mg/kg/day), on the gradedly increased dosage schedule with a dosage level of 0.5 vs. 1 mg/g food to 4 mg/g food. In the natural withdrawal following administration, no significant withdrawal signs were observed in any group. In a substitution test either for phenobarbital or morphine, no suppression of withdrawal signs during the period of cross-administration of ifenprodil and no maintenance of dependence were observed. In a physical dependence-producing test, the rats fed ifenprodil never manifested withdrawal signs such as diarrhea, "wet shakes", sudden loss of body weight as in the levallorphan precipitation test. Ifenprodil apparently has no physical dependence liability. 相似文献
92.
Modulation of BUdR labeling index in rat brain tumors following intracarotid ACNU administration 总被引:1,自引:0,他引:1
Katsuyoshi Mineura Katsuo Watanabe Ichiro Izumi Masayoshi Kowada 《Journal of neuro-oncology》1992,14(3):201-205
Summary Chloroethy1nitrosourea (CENU) chemotherapy has yielded limited benefit on survival of malignant brain tumors. Intracarotid administration of CENU is expected to have the advantage of increasing drug concentration reaching tumors. To understand basic knowledge of intracarotid chemotherapy, we monitor changes of proliferating rate after intracarotid injection of 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2chloroethyl)-3-nitrosourea hydrochloride (ACNU), using a bromodeoxyuridine (BUdR) labeling index (LI) in transplanted brain tumors of three cell strains.C6-2 tumor cells were in vitro sensitive to ACNU, and C6-2/ACNU and C6-1 cells were resistant. The drug sensitivity to ACNU was as follows: 11.9 tM in the C6-2 cells, 46.0 M in the C6-2/ACNU cells, and 49.7 M in the C6-1 cells at SD10, which gives 10% survival of clonogenic cells. The intracarotid ACNU at a dose of 30 mg/kg abruptly decreased the LI to 11% (mean) from 36% in C6-2 transplanted tumors. The LI remained low between 12 and 48 hours after, and then increased to the pretreatment level by 96 hours. In contrast, the LI of C6-1 tumors transiently fell to 15% from 42% at 12 hours after the injection, and subsequently increased to 36% at 24 hours and 37% at 48 hours.These results indicate that intracarotid ACNU administration shortly suppresses proliferating activity of tumors and that combined and alternating chemotherapy are mandatory for enhancing effectiveness of brain tumor chemotherapy. 相似文献
93.
S Beppu K Ikegami N Tanaka K Kumon S Izumi S Nakajima S Nakatani K Miyatake Y Nimura 《Journal of cardiology》1991,21(1):125-132
The pathogenesis of low cardiac output failure (LOF) immediately after open heart surgery was studied in 41 patients with LOF and 15 control patients without LOF using echocardiography. In 35 patients, transesophageal echocardiography was also performed. Left ventricular (LV) contraction was impaired in 28 of the 41 LOF patients, in whom LV fractional shortening was less than 25%. In the other 13 LOF patients, however, it was greater than 25%. In 12 of these 13 patients, transesophageal echocardiography revealed that accumulating pericardial coagula were localized in the right side of the heart, deforming the right atrial and ventricular chambers. The LV end-diastolic diameter was significantly less than the control, indicating that the pericardial coagula disrupted the distension of the heart. Emergent coagulotomy was performed in 5 patients, and hemodynamic conditions were improved. In spite of "cardiac tamponade", the wall motion and pressure tracings of the right atrium and right ventricle in these patients differed from those in fluid tamponade. Therefore, this condition should be designated "coagula tamponade." In the other 22 patients in whom transesophageal echocardiography was employed, no coagula were observed. Since pericardial coagula can hardly be detected by transthoracic echocardiography, transesophageal echocardiography is indispensable for diagnosing pericardial coagula noted immediately after open heart surgery. 相似文献
94.
We report a 5-year-old male patient with interhemispheric cysts which showed spontaneous reduction in size. The patient was consulted to our hospital at 2 days of life for the evaluation of intracranial cysts found by fetal ultrasonography. Magnetic resonance imaging (MRI) on admission disclosed multiple cysts in the interhemispheric region and agenesis of the corpus callosum. MRI performed later disclosed the association of pachygyria and heterotopia. On follow-up MRIs, the cysts peaked in size at 5 month of age and gradually reduced thereafter. He showed transient hypertonia but had neither neurological deficits nor signs of increased intracranial pressure except transient hypertonia throughout the course. The present case is the first with interhemispheric cysts showing spontaneous reduction in size. While the present case suggested that an interhemispheric cyst dose not necessarily need a surgical treatment, and that it is difficult to determine surgical indication based on clinical manifestations. 相似文献
95.
Kato M Imamura M Hosotani R Shimada Y Doi R Itami A Komoto I KosakaM T T Konishi J 《World journal of surgery》2000,24(11):1425-1430
The intravenous secretin injection test (secretin test) has been used for the differential diagnosis of gastrinoma. In this
study we report that the intraoperative secretin test (IOS test) is also useful for determining the extent of curability in
patients with Zollinger-Ellison syndrome (ZES). Twelve patients with ZES underwent surgical exploration and the IOS test.
The results of the IOS test were obtained by rapid radioimmunoassay of the serum gastrin level (IRG) within 60 minutes. The
test was diagnosed as negative when the maximum increase of serum IRG was less than 80 pg/ml and also less than 20% of the
basal serum IRG level. Three of the twelve patients underwent pancreatoduodenectomy (PD), and two patients underwent distal
pancreatectomy. Extirpation of duodenal tumors with dissection of regional lymph nodes was performed in seven patients. In
two of the seven patients the IOS test remained positive after extirpation of the duodenal tumors and the dissection of regional
lymph nodes. In one patient PD was performed on the basis of the positive results, and the IOS test became negative after
PD. In the other patient, two tiny metastatic liver tumors were identified and were resected, but the IOS test did not become
negative. We closed the abdomen in 11 patients when we obtained negative results from the IOS test. The results of the IOS
test were almost identical to the data obtained by the standard assay postoperatively. The serum IRG levels of all but one
patient fell to the normal level, and the secretin test became negative postoperatively. The IOS test is thus useful and indispensable
for curative resection of microgastrinomas in patients with ZES. 相似文献
96.
An experimental study of the effects of nerve root retraction on the posterior ramus 总被引:7,自引:0,他引:7
STUDY DESIGN: The histologic and ultrastructural changes in the posterior ramus after posterior lumbar surgery were studied in rabbits. OBJECTIVE: To investigate the structural changes in the posterior ramus after posterior lumbar surgery that may cause injury to the posterior ramus after the procedure. SUMMARY OF BACKGROUND DATA: Investigators in previous studies have pointed out that low back discomfort after lumbar discectomy relates to neurogenic changes and/or myogenic changes of paravertebral muscle. However, no previous study has demonstrated the effects of excessive nerve root retraction on spinal posterior rami. METHODS: Eighteen male Japanese White rabbits were used. The posterior ramus arising from the S1 nerve root was examined after exposure of the lamina only, fenestration, or retraction of the S1 nerve root, with light microscopy and transmission electron microscopy at 2, 4, and 6 weeks after the procedure. Results were compared with a those in control specimens that did not undergo the procedure. RESULTS: In the exposed group, no distinct difference was found compared with the control specimen. In the fenestration group, especially at 6 weeks, some attenuation and splitting of myelin sheaths was observed. In the retraction group, the structural alteration was most severe. Even at 2 weeks, fragmentation of many myelin sheaths was detected. Examination of specimens by electron microscopy indicated phagocytosis of myelinated fibers at 4 and 6 weeks. CONCLUSIONS: Findings showed that posterior lumbar procedures, including retraction of paravertebral muscle, fenestration of the lamina, and retraction of the nerve root affect the posterior ramus. Excessive retraction of the nerve root has an especially disastrous effect on the posterior ramus. Such a violent maneuver within the spinal canal must be avoided. 相似文献
97.
Isoflavone aglycone-rich extract without soy protein attenuates atherosclerosis development in cholesterol-fed rabbits 总被引:17,自引:0,他引:17
Yamakoshi J Piskula MK Izumi T Tobe K Saito M Kataoka S Obata A Kikuchi M 《The Journal of nutrition》2000,130(8):1887-1893
The antiatherogenic effect of soy protein with intact isoflavones is well established, but the effects of isoflavones without soy protein have not been determined. We investigated the antiatherogenic effect of an isoflavone aglycone-rich extract (containing 429.4 mg/g isoflavone aglycones) without soy protein from fermented soy in cholesterol-fed rabbits. We fed 12-wk-old New Zealand white male rabbits diets containing 1 g/100 g cholesterol with 0, 0.33 or 1 g/100 g isoflavone aglycones for 8 wk. We also fed the rabbits a diet containing 1 g/100 g cholesterol with 1.09 g/100 g soy saponin-rich extract, a component other than isoflavone aglycones in the isoflavone aglycone-rich extract. Controls did not consume cholesterol, isoflavone aglycones or saponins. The isoflavone aglycone- and saponin-rich extracts did not affect the serum lipid profile of cholesterol-fed rabbits. The serum concentration of daidzein in its conjugated form was significantly higher in the high isoflavone group than in the low isoflavone group. The level of cholesteryl ester hydroperoxide (ChE-OOH) induced by CuSO(4) in plasma in the high isoflavone group was significantly less than that in the cholesterol group, and the ChE-OOH levels of LDL in the low and high isoflavone groups were significantly less than those in the cholesterol group. The ChE-OOH levels in plasma and LDL in the saponin group did not differ from the cholesterol group. In the aortic arch, the cholesterol concentration was significantly lower in the high isoflavone group, and malondialdehyde concentration was significantly lower in the low and high isoflavone groups compared with the cholesterol group; however these concentrations in the saponin group did not differ from those in the cholesterol group. The atherosclerotic lesion area of the aortic arch was significantly lower in the isoflavone groups (26.3% lower in the low isoflavone group and 36.9% lower in the high isoflavone group) than in the cholesterol group. The lesion areas were not different in the soy saponin and cholesterol groups. Immunohistochemical analysis revealed fewer oxidized LDL-positive macrophage-derived foam cells in atherosclerotic lesions in the aortic arch of isoflavone groups compared with that of the cholesterol group. These results suggest that the antioxidative action of isoflavones and their antioxidative metabolites inhibit the oxidation of LDL, thereby exerting an antiatherosclerotic effect. 相似文献
98.
Hiroyuki Suzuki Shichisaburo Abo Michihiko Kitamura Masaji Hashimoto Keiichi Izumi Kunihiko Terada Toshihiro Sugiyama 《Cancer investigation》1997,15(5):411-415
Gene amplification is a relatively frequent event in human malignant tumors and is believed to play an important role in tumor progression. The int-2 and erbB genes are amplified more frequently than any other genes in human esophageal cancer. In order to investigate the correlation between these two proto-oncogenes and the clinical behavior of esophageal cancer, we examined DNA amplification of int-2 and erbB and analyzed their relationship to clinicopathological variables. Genomic DNA was extracted from 21 esophageal squamous carcinomas and normal esopfiageal mucosa, as well as from 4 metastatic tumors. We used Southern blot analysis for detection of gene amplification. Amplification of int-2 was observed in 13 of 21 cases (62%) and in all the metastatic tumors (4/4; 100%). We found a significant correlation between amplification of int-2 and the length of the primary lesion. Amplification of erbB was detected in 3 of 18 patients (17%). All patients who showed amplification of erbB also demonstrated amplification of int-2. These results suggest that amplification of int-2 or neighboring genes on 11q may participate in tumor progression and metastasis in patients with esophageal squamous cancer. 相似文献
99.
目的 探讨正常双胎妊娠期间胎儿大脑中动脉搏动指数的变化;并与正常单胎进行比较.方法 采用彩色多普勒超声对34例正常双胎及176例正常单胎胎儿从孕23周至孕35周进行大脑中动脉搏动指数测定.结果 正常双胎胎儿大脑中动脉搏动指数随孕周呈逐渐下降趋势,与正常单胎胎儿比较,孕29周前该值为低,以后较之略高.结论 孕29周后双胎胎儿大脑中动脉血流阻力比单胎其值为高. 相似文献
100.
Asahi H Takeda M Takashima M Koshida K Uchibayashi T Namiki M Minato H Siba N Hasegawa M 《Hinyokika kiyo. Acta urologica Japonica》2000,46(6):397-400
We report a case of chromophobe cell renal carcinoma. A 27-year-old male suffered from right flank pain and gross hematuria. Drip infusion pyelography and ultrasonographic examination revealed a right renal mass and it was diagnosed as renal oncocytoma by needle biopsy of the right kidney. He was referred to our hospital for the operation and right radical nephrectomy was performed. The cut surface of the tumor was beige in color. The cytoplasm of the tumor cells stained positively for colloidal iron and showed a negative reaction for Vimentin. From these results, this tumor was given a diagnosis of chromophobe cell renal carcinoma. 相似文献