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排序方式: 共有4357条查询结果,搜索用时 15 毫秒
1.
2.
Shigeyoshi Gon MD Yoshihito Irie MD Mono Takahashi MD 《General thoracic and cardiovascular surgery》2006,54(2):278-284
Objectives: Upper gastrointestinal bleeding, particularly from a stress-induced duodenal ulcer, is an extremely important perioperative complication in cardiovascular surgery. Methods: In the present study, 33 patients undergoing elective open heart surgery between July 2000 and February 2001 were allocated to either a famotidine (FAM) or rabeprazole (RPZ) group to examine the perioperative gastric and esophageal pH readings, in conjunction with an investigation into the effect of infection with Helicobacter pylori (HP). Results: Postoperative upper gastrointestinal bleeding did not occur in either group, and the intraoperative and postoperative mean gastric pH readings, as well as the holding time pH> 6, suggested sufficient acid suppression by either drug. Gastric acid secretion was less strongly suppressed in HP-negative patients in the FAM group, but was unaffected by HP infection status in the RPZ group. Conclusion: The FAM group and RPZ group revealed a sufficient effect of gastric acid suppression. It was indicated that FAM had an insufficient effect of gastric acid suppression for HP-negative patients. 相似文献
3.
The ganglioside composition of human melanoma was analyzed in five sets of tumor specimens obtained directly from surgery, from the autologous tissue culture cell lines, and from the autologous cell lines grown in athymic nude mice. Total gangliosides of these 15 melanoma specimens were isolated and purified, and the amount of each component ganglioside was analyzed by thin-layer chromatography and a thin-layer chromatography scanner. The ganglioside composition of the five surgical melanoma specimens clearly exhibited different patterns from each other. Moreover, none of the autologous cultured melanomas possessed the same ganglioside composition as their original biopsied tumors. However, when these melanoma cell lines were transplanted into nude mice, the ganglioside composition was converted back to the same ganglioside pattern as in the original surgical specimens. The results support the view that changes in the ganglioside composition of melanoma during in vitro growth are caused by the culture environment rather than by selection of melanoma cells with a particular genotype. Reestablishment of the original ganglioside patterns after passage in nude mice provides clear evidence that in vivo expression of gangliosides is a conserved and stable function specified by the human melanoma cells. 相似文献
4.
Hidekazu Mukai Hiroshi Yoshinaga Akihiko Watanabe Hitoshi Fujiwara Tsuyoshi Fujita 《Digestive endoscopy》2004,16(Z1):S58-S61
After removal of intraductal stones, a 10‐Fr or 7‐Fr pancreatic stent was placed in 16 patients with upstream ductal dilation proximal to a stricture of the main pancreatic duct. Stents were removed after a mean duration of 52.5 days. Nine patients underwent repeated stenting. About one year after removal of the initial stent, when the remaining upstream ductal dilation was found on follow‐up pancreatograms, the next stent was replaced. Repeated stenting improved outflow of pancreatic juice more effectively than one‐time stenting. Correlation between long‐term pain relief without recurrence of intraductal stones and reduction of duct diameter was also shown. Stent occlusion was observed in 14 of 30 stents. Stent occlusion was frequently associated with recurrence of pancreatitis and intraductal stones, and was also associated with morphologic changes in the pancreatic ductal system. Although there were no significant differences between stent patency of the initial stents and that of the next stents, stent patency of 10‐Fr stents was superior to that of 7‐Fr stents. 10‐Fr stents should be removed within 8 weeks and 7‐Fr stents should be removed within 4 weeks for the prevention of stent occlusion. Repeated stenting with short‐term stenting is therefore considered a safe and effective protocol of endoscopic pancreatic stenting. 相似文献
5.
6.
Kengo Yoshimitsu Hiroshi Honda Kuniyuki Kaneko Toshiro Kuroiwa Hiroyuki Irie Takashi Ueki Kazuo Chijiiwa Kenji Takenaka Kouji Masuda 《Journal of magnetic resonance imaging : JMRI》1997,7(4):696-701
Forty-nine pathologically proven gallbladder lesions were evaluated in 45 patients using dynamic MRI with a spoiled gradient pulse sequence (SPGR), to access the ability of this technique to differentiate benign from malignant gallbladder lesions. The studies were reviewed retrospectively. Signal intensity of the lesions were measured. Twenty-one malignant and 28 benign lesions were classified into three categories: polypoid, diffuse wall thickening, and exophytic. Early and delayed enhancement patterns were evaluated. For the polypoid masses, malignant lesions (n = 9) demonstrated early and prolonged enhancements, whereas benign lesions (n = 14) had early enhancement with subsequent washout (P < .05). For diffuse gallbladder wall thickening, malignant lesions (n = 6) demonstrated early and prolonged enhancement and benign lesions (n = 14) showed relatively slow, prolonged enhancement (P < .05). The exophytic masses (n = 6) all were malignant and demonstrated early and prolonged enhancement. Dynamic MRI can help differentiate benign from malignant gallbladder lesions. 相似文献
7.
Inhibition of HIV-1 infectivity with curdlan sulfate in vitro 总被引:5,自引:0,他引:5
Y Kaneko O Yoshida R Nakagawa T Yoshida M Date S Ogihara S Shioya Y Matsuzawa N Nagashima Y Irie 《Biochemical pharmacology》1990,39(4):793-797
Polymethoxylated flavones and C-glycosyl derivatives isolated from medicinal plants besides other flavonoid compounds were studied for their influence on lipid peroxidation induced by FeSO4+ cysteine in rat liver microsomes. A number of hydroxyflavones (e.g. luteolin); C-glycosyl-flavones (e.g. orientin); methoxyflavones (e.g. gardenin D) and flavonols (e.g. datiscetin), as well as the flavanol leucocyanidol and the biflavone amentoflavone behaved as inhibitors of non-enzymic lipid peroxidation. Structure-activity relationships were established and it was observed that the structural features for active polyhydroxylated compounds were different from those of polymethoxylated flavones, antiperoxidative flavonoids possessing a high lipophilicity. 相似文献
8.
Alveolar hydatid disease of the liver: computed tomography and transabdominal ultrasound with histopathological correlation. 总被引:5,自引:0,他引:5
K Choji N Fujita M Chen A S Spiers Y Morita M Shinohara T Nojima G Irie 《Clinical radiology》1992,46(2):97-103
The appearances of alveolar hydatid disease of the liver (AHDL) on computed tomography (CT) and ultrasound (US) were retrospectively compared with histopathological appearances in 67 patients with 100 separate lesions. The radiological features were correlated directly with the pathological specimens obtained from each patient. We conclude that the CT appearances are more specific, but that US has a role to play in mass screening in endemic areas, and intraoperatively. 相似文献
9.
To improve the rectal delivery of ethyl 4-biphenylylacetate (EBA), a prodrug of the anti-inflammatory drug 4-biphenylylacetic acid (BPAA), the use of highly water-soluble 2-hydroxypropyl-beta-cyclodextrin (HP-beta-CyD) and heptakis(2,6-di-O-methyl)-beta-cyclodextrin (DM-beta-CyD) was investigated and compared with the use of the parent beta-cyclodextrin (beta-CyD). Among the three beta-CyDs, HP-beta-CyD was best at improving the rectal bioavailability of EBA in rats after single and multiple administrations of oleaginous suppositories (Witepsol H-5) containing the complexes. To gain insight into the enhancing effect of beta-CyDs, the absorption behaviors of EBA (observed by monitoring BPAA as an active metabolite of EBA) and beta-CyDs themselves were examined in vitro, in situ, and in vivo. The in situ recirculation study revealed that the complexed form of EBA was less absorbable from the rectal lumen in the solution state, but this disadvantageous effect of beta-CyDs was compensated in part by the inhibition of the bioconversion of EBA to BPAA. When beta-CyDs were coadministered with EBA in vivo, however, rather high amounts of HP-beta-CyD (approximately 26% of dose) and DM-beta-CyD (approximately 21% of dose), compared with beta-CyD (approximately 5% of dose), were absorbed from the rat rectum. Thus, the enhancement of rectal absorption of EBA in vivo can be explained by the facts that the hydrophilic beta-CyDs increased the release rate of EBA from the vehicle and stabilized EBA in the rectal lumen and that the drug was partly absorbed in the form of the complex.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
10.
I. Akiguchi Hidekazu Tomimoto Toshihiko Suenaga Hideaki Wakita Herbert Budka 《Acta neuropathologica》1997,95(1):78-84
Binswanger’s disease is pathologically characterized by a combination of diffuse cerebrovascular white matter lesions and
lacunar infarcts in the basal ganglia and white matter. Although a blood-brain barrier (BBB) dysfunction has been implicated
in the pathogenesis of these white matter (WM) lesions, few authors have addressed this problem. In the present study, we
describe BBB dysfunction and its regional differences in the brains of Binswanger’s disease patients. Twelve brains from Binswanger’s
disease patients (group III) were examined and compared with those from five patients with non-neurological disease (group
I) and five cortical infarct patients without significant WM lesions (group II). Immunohistochemistry was performed for glial
fibrillary acidic protein and vimentin as astroglial cell markers, and for immunoglobulins, complements and fibrinogen as
extravasated serum protein markers. The grading scores for IgG extravasation were significantly higher in group III as compared
to group I, in both the periventricular WM and the subcortical WM (P < 0.01). In group III, the scores in the periventricular WM and subcortical WM were significantly higher than in the subcortical
U fibers and cerebral cortex (P < 0.01 for the periventricular WM; P < 0.001 for the subcortical WM), respectively. Clasmatodendritic astroglia, which had swollen cell bodies and large cytoplasmic
vacuoles with disintegrated processes, incorporated the serum components IgG, IgM, C3d, C1q and fibrinogen, both in the periventricular
WM and subcortical WM in 5 out of 12 (42%) Binswanger’s disease brains. These results indicate that WM lesions in Binswanger’s
disease are accompanied by BBB dysfunction, although it remains uncertain whether BBB dysfunction is secondary to either chronic
cerebral ischemia or arterial hypertension.
Received: 25 April 1997 / Revised, accepted: 21 July 1997 相似文献