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991.
A 65-year-old Japanese man was hospitalized with back pain in April 1998. At age 63 years, endoscopic ablation with cyanoacrylate glue had been performed for bleeding gastric varices. At the time of the present admission, a low-density mass (about 23mm in diameter) was seen in the tail of the pancreas, and splenic vein occlusion and collateral veins were revealed on computed tomography. A hypoechoic tumor (about 22mm in diameter) and splenic vein occlusion were clearly visualized on the pancreas tail via endoscopic ultrasonography. Venous phase of the splenic arteriogram revealed a completely occluded splenic vein in the hilus of the spleen. Thus, the patient was diagnosed with pancreatic cancer (stage I: T2N0M0). A surgical resection of the pancreatic tumor was performed, and a pancreatic tail resection with part of stomach around the pancreas tail, and splenectomy, were selected for this patient, in June 1998. Histopathological examination of the resected tumor revealed capsuled abscess formation with foreign body reaction between the stomach and the pancreas tail, and necrosis was present in the pancreas around the abscess. There were some deposits of cyanoacrylate glue in the tumor. The mass was considered to be an inflammatory tumor. In summary, this case of inflammatory pancreas tumor is a novel complication after endoscopic obliterative therapy with cyanoacrylate glue.  相似文献   
992.
Background Helicobacter pylori CagA protein is considered to be one of the virulence factors associated with gastric cancer. CagA is injected into gastric epithelial cells, undergoes tyrosine phosphorylation, and binds to Src homology 2 domain-containing protein-tyrosine phosphatase (SHP-2). Two major subtypes of CagA have been observed in the SHP-2-binding site, the Western and East Asian types. The East Asian-type CagA binds to SHP-2 more strongly than the Western-type CagA. The diversity of CagA, which collectively determines the binding affinity of CagA to SHP-2, may be an important variable in determining the clinical outcome of infection by different H. pylori strains. Methods We investigated the relationship between the diversity of CagA and clinical outcome in Okinawa, Japan. A total 24 strains, 13 gastric cancer strains and 11 duodenal ulcer strains, were studied. We sequenced full-length cagA genes and analyzed the phylogenetic relationships between Okinawa isolates and previously characterized Western H. pylori strains. Results All isolates examined were cagA positive. The prevalence of East Asian CagA-positive strains was significantly higher in patients with gastric cancer (84.6%) than in patients with duodenal ulcer (27.3%) (χ-squared = 8.06, P = 0.011). The phylogenetic analysis showed that all gastric cancer strains with East Asian-type CagA were in the East Asian cluster, and that most duodenal ulcer strains were in the Western cluster. Conclusions The origins of H. pylori isolates are different between gastric cancer strains and duodenal ulcer strains, and East Asian CagA-positive H. pylori infection is associated with gastric cancer. The strain diversity observed in Okinawa may affect the difference in the prevalence of disease associated with H. pylori infection in Japan.  相似文献   
993.
A 29-year-old man was admitted with fever and anorexia. Radiographic examinations of the chest showed a localized peripheral non-segmental air-space consolidation in the right lower lobe. He had a history of exposure to parakeets, and psittacosis was diagnosed based on the elevated serum complement fixation titer against Chlamydia psittaci. The common radiographic finding of psittacosis is ground-glass attenuation radiating from the hilar areas. We report a rare case of psittacosis presenting a localized consolidation, clearly limited to the subpleural region of the lung.  相似文献   
994.
We investigated the efficacy of a dose-intensified double-CHOP regimen followed by high-dose chemotherapy with or without peripheral blood stem cell transplantation (PBSCT) in 11 patients with four types of peripheral T-cell lymphoma (PTCL). Three of the 4 patients with unspecified PTCL (PTCLu) achieved complete response (CR); 1 patient relapsed and 1 died of secondary leukemia after consolidation therapy. All angioimmunoblastic T-cell lymphoma (AILT) and subcutaneous panniculitis-like T-cell lymphoma (SPTCL) patients achieved CR; 5 of 6 have remained disease free for more than 3 years. The patient with hepatosplenic lymphoma did not achieve CR even after PBSCT and underwent allogenic bone marrow transplantation (allo-BMT). Thus, our regimen appears to be effective for high-risk AILT and SPTCL. However, allo-BMT should be considered for high-risk of PTCLu and hepatosplenic T-cell lymphoma.  相似文献   
995.
Three tumor markers for hepatocellular carcinoma (HCC) are available in daily practice in Japan: alpha-fetoprotein (AFP), des-gamma-carboxy prothrombin (DCP), and lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3). To elucidate the predictability of these tumor markers on HCC recurrence after curative ablation, we enrolled 416 consecutive patients with na?ve HCC who had been treated by percutaneous ablation at our department from July 1997 to December 2002. Tumor marker levels were determined immediately before and 2 months after the treatment. Complete ablation was defined on CT findings as nonenhancement in the entire lesion with a safety margin. Tumor recurrence was also defined as newly developed lesions on CT that showed hyperattenuation in the arterial phase with washout in the late phase. We assessed the predictability of recurrence via tumor markers in multivariate analysis, using proportional hazard regression after adjusting for other significant factors in univariate analysis. Until the end of follow-up, tumor recurrence was identified in 277 patients. Univariate analysis revealed the following factors to be significant for recurrence: platelet count; size and number of tumors; AFP, AFP-L3, and DCP preablation; and AFP and AFP-L3 postablation. Multivariate analysis indicated that AFP >100 ng/mL and AFP-L3 >15%, both pre- and postablation, were significant predictors. The positivity of AFP and AFP-L3 preablation that turned negative postablation was not significant. In conclusion, tumor markers pre- and post-ablation were significant predictors for HCC recurrence and can complement imaging modalities in the evaluation of treatment efficacy.  相似文献   
996.
Many animals employ sex pheromones to find mating partners during their reproductive seasons. However, most sex pheromones of vertebrates remain to be identified. Over the past 20 years, steroids and prostaglandins have been identified as sex pheromones in several fishes. These pheromones are broadly termed "hormonal pheromones" because they or their precursors act as hormones in these fishes. Hitherto, no other type of sex pheromone has been unambiguously identified in teleost fish. Here we report the identification of a "nonhormonal pheromone" in teleost fish. The urine of the reproductively mature female masu salmon (Oncorhynchus masou) contains a male-attracting pheromone. Bioassay-guided fractionation yielded an active compound that was identical to L-kynurenine in spectral and chromatographic properties. L-Kynurenine is a major metabolite of L-tryptophan in vertebrates. This pheromone elicits a male-specific behavior at even picomolar concentrations; its electrophysiological threshold is 10(-14) M. L-Kynurenine is a reasonable substance for female masu salmon to advertise their readiness for mating.  相似文献   
997.
OBJECTIVE: To determine the frequency and clinical association of antiphosphatidylserine-prothrombin complex (PS/PT) antibody (Ab) in systemic sclerosis (SSc). METHODS: Anti-PS/PT IgG Ab was examined by enzyme linked immunosorbent assay (ELISA) in 112 patients with SSc. Thirty three healthy volunteers and 30 patients with systemic lupus erythematosus (SLE) were also investigated as controls. RESULTS: Anti-PS/PT Ab was detected in 18/112 (16%) patients with SSc and 10/30 (33%) patients with SLE, whereas it was not detected in any normal controls. Anti-PS/PT Ab was more frequently detected in patients with SSc with peripheral ischaemia and lung disease (pulmonary fibrosis and pulmonary hypertension) than in patients with SSc without the Ab. However, anti-PS/PT Ab was not associated with the severity of skin sclerosis. Importantly, two patients were negative for both lupus anticoagulant and Ab against cardiolipin beta(2)-glycoprotein I complex among six anti-PS/PT Ab positive patients with SSc and a thromboembolic episode. CONCLUSIONS: Anti-PS/PT Ab is associated with thromboembolism, peripheral ischaemia, and lung involvement in some patients with SSc. Examination of this Ab may be useful to recognise the risk of thromboembolism in patients with SSc.  相似文献   
998.
The number of physicians engaged in basic science and teaching is sharply decreasing in Japan. To alleviate this shortage, central government has increased the quota of medical students entering the field. This study aimed to determine the characteristics of physicians who are engaged in basic science in efforts to recruit talent. A questionnaire was distributed to all 30 physicians in the basic science departments of Juntendo University School of Medicine. Question items inquired about sex, years since graduation, years between graduation and time entering basic science, clinical experience, recommending the career to medical students, expected obstacles to students entering basic science, efforts to inspire students in research, increased number of lectures and practical training sessions on research, and career choice satisfaction. Correlations between the variables were examined using χ(2) tests. Overall, 26 physicians, including 7 female physicians, returned the questionnaire (response rate 86.7%). Most physicians were satisfied with their career choice. Medical students were deemed not to choose basic science as their future career, because they aimed to become clinicians and because they were concerned about salary. Women physicians in basic science departments were younger than men. Women physicians also considered themselves to make more efforts in inspiring medical students to be interested in research. Moreover, physicians who became basic scientists earlier in their career wanted more research-related lectures in medical education. Improving physicians' salaries in basic science is important to securing talent. In addition, basic science may be a good career path for women physicians to follow.  相似文献   
999.
BACKGROUND: Until now, large-scale nationwide surveys of acute myocardial infarction (AMI), such as those performed in Europe and America, have not been performed in Japan. Therefore, in 2000 the Japanese Coronary Intervention Study (JCIS) group conducted a nationwide survey on the incidence of AMI in Japan. METHODS AND RESULTS: Questionnaires were collected from 8,268 facilities throughout Japan. The total annual number of patients with AMI was 66,459 (52.4 patients/10(5) population), and the AMI incidence rate in Japan was approximately 25% of that in the United States. Most facilities with AMI patients treated less than 50 AMI patients annually, and that number was 45.0% of total AMI patients. The incidence of AMI patients was highest in Kochi, Kumamoto, and Wakayama prefectures, and lowest in Yamanashi, Saitama and Shiga prefectures. The ratio of the highest incidence to the lowest incidence was 2.0. A significant correlation was observed between the mean age of the prefectural population, as a coronary risk factor, and the incidence of AMI. CONCLUSIONS: The incidence of AMI in Japan is approximately 25% that in the United States and it varies considerably among the prefectures, one of the causes being the difference in the mean age. This provides important information for assessing the guidelines for Japanese patients with AMI.  相似文献   
1000.
SETTING: The incidence of tuberculosis in Japan has fallen rapidly in the past 50 years, to 27.9 cases per 100,000 population in 2001. OBJECTIVE: To assess the molecular epidemiology of tuberculosis in the north Hokkaido district, Japan. DESIGN: Restriction fragment length polymorphism analysis was consecutively performed on Mycobacterium tuberculosis strains from patients with pulmonary tuberculosis from April 1999 to March 2002. RESULTS: Of 229 patients, strains from 227 (99.1%) were available for analysis. The mean age of the patients analysed was 69.4 years. There was one immigrant patient. Two hundred and seven patients had six or more copies of IS6110. Of these, 16 (7.7%) in eight clusters had identical patterns, 120 (58.0%) belonged to five groups that had similar patterns (Dice coefficient >0.7) and 80 (38.6%) belonged to the 35 groups with the most common patterns (Dice coefficient >0.9). CONCLUSION: These results may reflect the epidemiological characteristics, age and migration of the residents and the incidence of tuberculosis of the area, and also those of Japan: many elderly patients were infected in the past, when the incidence of tuberculosis was very high.  相似文献   
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