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991.
We encountered two cases of ruptured anastomotic pseudoaneurysms 47 and 77 months after surgery for atherosclerotic thoracic aortic aneurysms. Autopsy was performed in one case and emergency re-operation was performed in the other case. We gained some interesting findings in the autopsy and the re-operation. The anastomotic sites were sustained by sutures only, and there was no evidence of tissue supplementation at the anastomotic sites in macroscopic observation. Microscopic findings demonstrated endothelium healing on the internal side of the prosthesis near the anastomotic site. There was no tissue connection between the prostheses and the native aortic walls, although over four or six years had passed after the previous anastomoses. Anastomotic pseudoaneurysms may occur even in a long time after surgery. Careful operative procedures and long-term computed tomography or magnetic resonance imaging follow-up are crucial.  相似文献   
992.
The objective of our study was to determine the correlation between gallbladder opacification by delayed CT and contrast-associated nephropathy (CAN). Delayed CT after angiography was performed in 269 patients. Gallbladder opacification was defined when the CT value in gallbladder was more than 30 HU. Positive renal dysfunction was recognized as CAN which defined as an increase in serum creatinine level > 0.3 mg/dl and > 20 % on days 1, 3, or 7. Gallbladder opacification appeared in 154 of 269 (57 %) patients and CAN in 35 (13 %) patients. Of 117 patients without gallbladder opacification, 17 CAN (14 %) were recognized, and of 152 patients with gallbladder opacification, 18 CAN (12 %) were recognized. No significant correlation existed between delayed gallbladder opacification and CAN. Received 20 August 1996; Revision received 19 December 1996; Accepted 27 January 1997  相似文献   
993.
Eosinophilia is observed in a variety of disorders including acute and chronic graft-versus-host disease (GVHD). The clinical records of 237 patients who underwent allogeneic stem cell transplantation (allo-SCT) were retrospectively reviewed. Eosinophilia, defined as a relative eosinophil count>4% within the first 100 days, was observed in 135 patients (57%). The incidence of grades II-IV acute GVHD was significantly higher in patients without eosinophilia than in those with eosinophilia (68% vs. 43%; P<0.001). The incidence of chronic GVHD was significantly higher in patients without eosinophilia than in those with eosinophilia (73% vs. 56%; P=0.011). Relapse rate was similar between patients with and without eosinophilia (33% vs. 27%; P=0.438). The probability of nonrelapse mortality was 10% in patients with eosinophilia, which was significantly lower than that in patients without eosinophilia (31%; P<0.001), and the overall survival (OS) at 3 years was 67% in patients with eosinophilia, which was significantly higher than that in patients without eosinophilia (51%; P=0.003). Multivariate analysis identified older age, high-risk disease, acute GVHD, sex disparity between patient and donor, and the absence of eosinophilia as significant factors for reduced OS. These data lead us to conclude that eosinophilia after allo-SCT may serve as a favorable prognostic marker.  相似文献   
994.
To investigate the role of interferon gamma in the pathogenesis of Crohn's disease, we examined the interferon gamma levels of serum, supernatant of cultured peripheral blood mononuclear cells activated by phytohemagglutinin, and medium of organ culture of colonic mucosa in Crohn's disease. Serum interferon gamma levels in Crohn's disease, especially in active or non-resected Crohn's disease, were more elevated than those in normal subjects. In contrast, the production of interferon gamma by peripheral blood mononuclear cells was reduced in Crohn's disease. In some patients, interferon gamma levels of organ culture medium of colonic mucosal tissue specimens were elevated. When peripheral blood mononuclear cells were preincubated for 72 hours, interferon gamma production in Crohn's disease increased from 23.8% to 62.3% in comparison to levels in healthy controls. These results indicate that elevated serum interferon gamma in Crohn's disease may originate from the intestine, and interferon gamma may be related to the immune reaction and inflammation in the intestine.  相似文献   
995.
Activation of PC12 cells by lipophilic components of Panax ginseng.   总被引:3,自引:0,他引:3  
The lipid soluble fraction of Panax ginseng C. A. Meyer has been found to possess a stimulatory effect on a para-neuronal culture cell line, namely PC12 cells. Addition of the diethyl ether extract (0.025-0.1 mg/ml) of Ginseng radix to a culture medium promoted the outgrowth of neurites from cells dose-dependently as well as their ready differentiation to respond to carbachol and high KCl-evoked membrane depolarization to induce free Ca2+ accumulation in the cells within a week of culture. Effective constituents of the extract were confined to four major substances detected in the extremely lipophilic front area on silica gel TLC.  相似文献   
996.
Male ICR mice were exposed to silane 1000 ppm, a concentration 200 or 2000 times higher than the recommended occupational exposure limits by many countries and academic associations, for 1, 2, 4, and 8 h (phase I study) and for 6 h/day, 5 days/week, over 2 and 4 weeks (phase II study). Hematological and biochemical studies were performed, and the animals were examined for histopathological lesions of the cornea, nasal cavity, respiratory tract, lung, liver, kidney, spleen, pancreas, thymus, thyroid, bone marrow, salivary glands, esophagus, and testis. All mice in both studies survived until they were sacrificed. In the phase I study, no exposure-related changes were found as a result of the hematological, biochemical, or histopathological examinations. In the phase II study, hematological and biochemical examinations failed to reveal any exposure-related changes, but mild irritation, manifested in the form of a small amount of exudate (eight out of ten animals), and inflammatory cells and/or necrotic cells on the nasal mucosa (six out of ten animals) was observed in the mice exposed to silane for 4 weeks. These findings suggest that silane toxicity and irritation are not severe.  相似文献   
997.
The survey was done to clarify how the behavior of drinking alcoholic beverages of female nursing students relates to the stress they feel in their school life. The questionnaires were sent to 337 female students of two nursing schools located in metropolitan area. Students were asked to reply the questions of Adolescent Alcohol Involvement Scale (AAIS), and other questions related to their smoking habits and stress felt in their school life. Alcohol misusers who scored 42 points or more on AAIS were 13.7% of the valid respondents and non-drinkers and those who scored 19 and under on the scale were 4.1%. Those who drink more than over per week accounted for 12.0%, and those who have more than 3 drinks at one time accounted for 61.5%. Those who experienced alcohol drinking during childhood replied that this was encouraged by their parents. Those parents were found to be very generous about children's drinking at home later. The analysis of stress factors in students' life in relation to drinking behavior revealed that the students with scores on AAIS above 42 tended to show less eagerness in studying, and that clinical practice and report writing did not give than much stress.  相似文献   
998.
Epidemics of acute haemorrhagic conjunctivitis caused by a variant of coxsackievirus A24 (CA24v) and enterovirus 70 (EV70) have occurred periodically in Singapore. A seroepidemiological survey conducted before the CA24v epidemic in 1985 and in the midst of the EV70 epidemic in 1983 showed a neutralising antibody prevalence (greater than or equal to 1:4) of 19.1% and 66.9% to CA24v and EV70, respectively. The seropositivity rate to both viruses was highest in children 10-14 years of age, but no sex or ethnic difference was noted. It appears from the data that an epidemic could be triggered when the herd immunity of the population falls below a critical level. There was a significant correlation in seroprevalence between CA24v and EV70 (P = 7.75 x 10(-3).  相似文献   
999.
Hybrid carcinomas of the salivary gland are a recently defined and rare tumor entity, consisting of two histologically distinct types of carcinoma within the same topographic area. In this study, we examined nine such cases, which mainly arose in the parotid gland (seven cases), with an additional one each from submandibular and lacrimal glands, and analyzed their clinicopathologic profiles, including immunohistochemical features and p53 gene alterations. The prevalence of hybrid carcinomas was 0.4% among the 1863 cases of parotid gland tumors in our series. The nine patients comprised five men and four women, ranging in age from 40 to 81 years (mean, 62 y). Tumor size ranged from 2 to 10 cm (mean, 4.2 cm). Of the seven patients who were followed up, two were alive with disease and five were alive with no evidence of disease, although the follow-up period was short. Three cases had cervical lymph nodal metastases. The combinations of carcinoma components in our hybrid carcinomas were as follows: epithelial-myoepithelial carcinoma and basal cell adenocarcinoma in two cases, epithelial-myoepithelial carcinoma and squamous cell carcinoma in one case, salivary duct carcinoma and adenoid cystic carcinoma in two cases, myoepithelial carcinoma and salivary duct carcinoma in one, acinic cell carcinoma and salivary duct carcinoma in one, and squamous cell carcinoma and salivary duct carcinoma in two. Although the proportion of each carcinoma component in a tumor mass varied from case to case, the minor component always represented >or= 10% of the area. Differences in cellular composition were studied by immunohistochemistry and electron microscopy. The Ki-67-labeling index apparently differed between the two carcinoma elements in five cases. Diffusely positive p53 immunoreactivity was observed in four cases, restricted to the more aggressive component in each pair. Furthermore, p53 gene alteration analysis of these p53-positive cases revealed that all and three cases demonstrated loss of heterozygosity at p53 microsatellite loci and p53 gene point mutations, respectively, which were detected only in the p53-immunoreactive carcinoma component. Therefore, there is the possibility that such molecular-genetic events take an integral part for inducing the transformation from histologically lower to higher grade tumor during the hybrid carcinoma genesis of the salivary glands.  相似文献   
1000.
The pharmacokinetics and clinical efficacy of levofloxacin (LVFX, DR-3355), an optically pure S(-)-enantiomer of ofloxacin, were studied in patients after surgery. In the pharmacokinetic study, 4 patients undergoing bile drainage were given 2 100-mg tablets by mouth. Peak levels of LVFX were from 2.22 to 4.02 micrograms/ml of plasma at 2-4 hours after the oral administration, and from 7.5 to 11.3 micrograms/ml of bile at 2-6 hours. Forty-three patients with surgical infections, including 16 skin and soft-tissue infections and 12 wound infections, were treated with LVFX. Twenty-eight (70%) of the 40 patients whose results could be evaluated had excellent or good results; 42 (93%) of the 45 causative organisms identified were eradicated. An episode of diarrhea with chills and fever occurred in a 38-year-old man. The results suggested that LVFX has satisfactory antimicrobial effects in surgical infections.  相似文献   
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