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991.
992.
Two surgical cases of synchronous double esophageal and gastric cancer, both of which revealed a superficial type were investigated. The first case was a 58 years old man, who was found to have an abnormal gastric shadow on mass screening. Gastrointestinal examination revealed a synchronous double cancer of the esophagus (Mt-Lt, m) and stomach (L, m). An endoscopic mucosal resection was performed on the gastric cancer and after 3 weeks a blunt dissection on the esophageal cancer was performed and the gastric tube was reconstructed. The second case was a 65 years old man, who was found to have an ulcerative esophageal tumor (Ut, type 2) and a gastric tumor (M, 0-II c) at the anterior wall of the upper body on gastrointestinal examination for a complaint of hematemesis. A subtotal esophagectomy and a lymph node dissection was performed in which reconstruction was made by using a gastric tube avoiding the gastric cancer lesion. We also reviewed previous reports of 22 cases that had synchronous superficial esophageal and gastric cancer, and discussed the indications and methods of operation.  相似文献   
993.
To examine the effects of occupational and environmental neurotoxicants on vestibular, cerebellar and spinocerebellar functions, the following three groups of subjects were examined, using a computerized posturography with sway frequency analysis: (1) 49 male chemical factory workers exposed to lead stearate, aged 27-63 (mean 43) years, with concurrent blood lead concentrations (BPbs) of 11-113 (mean 48) microg/100 g and past mean BPbs of 7-52 (mean 24) microg/100 g; (2) 29 male sandal, shoe and leather factory workers, aged 35-73 (mean 51) years, with urinary 2,5-hexanedione (HD) concentrations of 0.41-3.06 (mean 1.20) mg/g creatinine; and (3) 9 females, aged 19-58 (mean 29) years, who were exposed to sarin accidentally 6-8 months before the study (Tokyo Subway Sarin Poisoning, March 20,1995) and showed plasma cholinesterase (ChE) activities of 13-95 (mean 68) IU/l on the day of poisoning. The pattern of posturographic changes in lead workers suggested that the vestibulocerebellum (lower vermis), anterior cerebellar lobe and spinocerebellar afferent pathway were asymptomatically affected; the vestibulocerebellar change reflected concurrent lead absorption and the anterior cerebellar one reflected past absorption. Similarly, vestibulocerebellar and spinocerebellar functions were affected by n-hexane in solvent workers; the effect on the vestibulocerebellar function was probably inhibited by xylene. Also, the chronic (long-term) effect on the vestibulocerebellar function persisted in acute sarin poisoning. It is thus suggested that the vesitibulocerebellar function is most sensitive to all the three chemicals examined. It appears that the computerized posturography with frequency analysis is a useful technique for assessment of vestibular, cerebellar and spinocerebellar effects in occupational and environmental health.  相似文献   
994.
995.
A 49-year-old man suffered from bilateral anterior ischemic optic neuropathy almost simultaneously, and was diagnosed with idiopathic aldosteronism associated with hypertension. Because this patient had multiple organ disorders, multiple cerebral infarctions, and a mild loss of renal function, it was important to treat his primary disease.  相似文献   
996.
Previous studies by our and other groups have shown that microbial products containing more than one epoxide group, including eponemycin, radicicol, depudecin and AGM-1470, exhibit anti-angio-genic activity in an in vivo assay system involving chorioallantoic membranes (CAMs) of growing chick embryos. Based on these findings, rhizoxin, a microbial metabolite that contains two epoxide groups and exhibits anti-tubulin activity, was tested for anti-angiogenic activity in a CAM assay system. Rhizoxin caused dose-dependent inhibition of embryonic angiogenesis, the IDS(1 value being 2 ng (3.2 pmol) per egg. In addition, this compound (2 nig/kg i.p.) significantly suppressed neovascnlarizatlou induced by M5076 mouse tumor cells in a mouse dorsal air sac assay system, compared to the vehicle alone (P<0.05). These results indicate that rhizoxin is a novel inhibitor of angiogenesis, and that it has potential as a new therapeutic agent for cancer.  相似文献   
997.
Two different erythroleukemia cell lines have been established from the splenic lesions of transgenic mice possessing the Friend spleen focus-forming virus (F-SFFV) gp55 gene. One showed a neardiploid karyotype and a temperature-sensitive (ts) p53 mutation, and the other, a hyper-triploid karyotype with double p53 mutations found by single-strand conformation polymorphism (SSCP) analysis. The cell lines both retained No.11 chromosomes on which p53 genes are localized. Another p53 allele in the cell line with the ts-p53 mutation appeared intact in the SSCP analysis of the genomic exon 5. The cells with the ts-mutant p53 gene showed no apparent change with temperature shift in their growth or dimethylsulfoxide-induced differentiation, although the wild-type p53 gene on the other allele was not expressing. This ts-p53val-135 gene made p53-deficient fibroblasts anchorageindependent at 37°C but not at 32°C. This non-virus-producing, mouse erythroleukemia cell line will be useful for the study of mutated p53 function during the induction of erythrodifferentiation or apoptotic change.  相似文献   
998.
The role of hepatocyte steatosis in interferon (IFN) resistance is still unclear, especially in patients infected with hepatitis C virus (HCV) genotype 2a. The present study was conducted in 364 consecutive non-cirrhotic naive patients infected with genotype 2a, who were evaluated for the severity of steatosis and response to IFN monotherapy after a 24-week median duration of therapy. The patients were examined for factors associated with steatosis and treatment efficacy according to the grade of steatosis. Early viral kinetics was also evaluated in 64 patients for predictors of response to therapy. Nine IFN-resistant patients were assessed for the relationship between amino acid sequence of HCV core region/NS5A and severity of steatosis. Multivariate analysis identified two independent factors associated with steatosis; serum ferritin > or =200 microg/l and body mass index > or =25.0 kg/m(2). The sustained virological response rate in patients with high-grade steatosis was significantly lower than in the low-grade group. Study of early viral kinetics showed a significantly lower cumulative HCV-RNA negative rate for the high-grade than low-grade steatosis group. Sequence analysis of HCV core region/NS5A in IFN-resistant patients with or without steatosis failed to identify steatosis-specific amino acid substitutions associated with resistance. This study of HCV genotype 2a suggested that steatosis is associated with excess iron storage, and that it is an important predictor of efficacy of IFN monotherapy. Further large-scale studies are warranted to examine the role of amino acid substitutions on IFN resistance specific for steatosis.  相似文献   
999.
To analyze the effect of human T-cell leukemia virus type I (HTLV-I) on cellular gene expression and its relation to tumorigenesis, two lines of transgenic mice carrying the long terminal repeat (LTR)-env-pX-LTR regions of the HTLV-I genome were produced. The transgene was expressed in many organs, including the brain, salivary gland, spleen, thymus, skin, muscle, and mammary gland. We found that the expression of the c-fos and c-jun genes, but not of thelyn and c-myc genes, was augmented 2- to 20-fold in histologically normal skin and muscle of these mice. The augmentation was tissue specific, suggesting the involvement of a cellular factor in the transgene action. In these mice, a three to seven times higher incidence of tumors was seen as compared with the control mice. These tumors included mesenchymal tumors, such as fibrosarcoma, neurofibroma, and lipoma, and adenocarcinomas of the mammary gland, salivary gland, and lung. The c-fos and c-jun genes were also activated in these tumors. The possible roles of elevated c-fos and c-jun gene expression in tumorigensis are discussed.The abbreviations used are ATL, adult T-cell leukemia; HTLV-I, human T-cell leukemia virus type I; IL-2, interleukin 2; IL-2R, interleukin 2 receptor; IL-6, interleukin 6; LTR, long terminal repeat.  相似文献   
1000.
The phenotypic expression of cardiomyopathy is greatly influenced by extrinsic factors other than intrinsic genetic defects, such as environmental stress. Exercise is assumed to be an important extrinsic factor, since sudden death is sometimes seen during exercise in young patients with hypertrophic cardiomyopathy (HCM). However, the long-term effects of mild exercise on phenotypic expression in cardiomyopathy remain unclear. To evaluate the effects of exercise performed during infancy or adolescence in cardiomyopathic patients, cardiomyopathic Syrian hamsters (BIO14.6) were subjected to swimming. BIO14.6 and age-matched congenic normal hamsters (CN) as controls were divided into three groups: sedentary (Sed), and trained during infancy (Inf) and during adolescence (Ado). Histological and biochemical analysis of 41-week-old hamsters revealed that (1) the relative level of beta-myosin heavy chain mRNA was significantly lower in the Inf group than in the Sed and Ado groups of BIO14.6. The level in the Inf group of BIO14.6 was compatible with that in the age-matched Sed group of the CN strain; (2) in BIO14.6, degenerative mitochondrial change in the cardiomyocytes was not seen in the Inf group while it was common in the Sed and Ado groups; (3) calcineurin phosphatase activity in the swimming group in 10-week-old CN was significantly higher than that of the age-matched sedentary group, and was as much as that of the swimming and sedentary groups in 10- and 41-week-old BIO14.6.  相似文献   
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