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51.
The effect of cigarette smoking or alcohol consumption on the risk of gastric cancer has not been clarified. We investigated this relationship, considering the anatomic subsite and histologic type of gastric cancer. A total of 19,657 men (aged 40-59 years at baseline), who responded to the baseline questionnaire and reported no serious illness at that time, were followed for 10 years, from January 1990 to December 1999. Gastric cancer was confirmed histologically in 293 men. Smoking was associated with an increased risk of the differentiated type of distal gastric cancer; compared to the group who never smoked, the adjusted rate ratios (RRs) of gastric cancer for past and current smokers were 2.0 (95% CI 1.1-3.7) and 2.1 (95% CI 1.2-3.6), respectively. No association was observed between cigarette smoking and risk of the undifferentiated type of distal gastric cancer except for a suggestive association with cardia cancer. For alcohol consumption, elevated risk was suggested only for cardia cancer of all histologic types, though the relationship failed to reach significance. Among those who drank alcohol at least once per week, RRs for ethanol intake of 2.7-161.0, 162.0-322.0 and 322.5+ g/week compared to those who drank 0-3 times/month were 2.5 (95% CI 0.7-9.5), 3.3 (0.9-11.6) and 3.0 (0.8-11.1), respectively (p(trend) = 0.66). In conclusion, our results confirm that smoking is related to gastric cancer of the differentiated type. Further studies with more cases are needed to detect a positive association between cigarette smoking or alcohol consumption and cardia cancer.  相似文献   
52.
BACKGROUND: Tissue factor (TF), the main initiator of blood coagulation, is involved in cancer metastasis and progression. We examined the role of TF on prostate cancer. MATERIALS AND METHODS: Immunohistochemical analysis was performed using the anti-TF antibody. Intra-tumoral blood vessels were visualized by staining endothelial cells with CD34 antibody. We examined the expression of TF and the microvessel density (MVD) in 66 biopsy specimens of prostate cancer, in order to investigate the relationship between the expression of TF and the clinicopathology of prostate cancer. RESULTS: TF antigen was positive in 41 (62%) of the specimens. There were significant differences in TF expression according to the pretreatment prostate specific antigen (PSA) level (p = 0.0193) and bone metastasis (p = 0.0029). MVD was significantly related to bone metastasis (p = 0.0175). TF-positive carcinomas more frequently presented high MVD expressions (p = 0.017) than TF-negative tumors. CONCLUSION: These results suggest that increased angiogenesis associated with TF expression might cause the metastasis and progression of prostate cancer.  相似文献   
53.
A 19-year-old, immunologically healthy man suffered from prolonged and intermittent high fever, left parotitis, systemic lymph node swelling, progressive liver dysfunction and leukocytopenia. 11 days after the fever onset, consciousness disturbance and generalized convulsion occurred. By the administration of γ-globulin and steroid, the patient recovered completely. Serum titers of IgG and IgM specific for both human parvovirus B19 and mumps were elevated, and parvovirus B19 DNA was identified in the serum. It was speculated that overlap infection of mumps and parvovirus B19 made the disease more severe in this patient.  相似文献   
54.
BACKGROUND AND AIMS: Hepatitis C virus (HCV)-specific cytotoxic T lymphocytes (CTL) may contribute to viral clearance and liver cell injury in patients with chronic hepatitis C. In the present study, we attempted to determine the serial HCV-specific CTL activity during interferon-beta (IFN-beta) therapy in patients with chronic hepatitis C and whether there is any relationship between the CTL response and clinical response to IFN-beta therapy. METHODS: Eight HLA-A2-positive patients with chronic hepatitis C were treated initially with 6 million U/ml of IFN-beta every day for 8 weeks and then 3 times weekly for the subsequent 16 weeks. Peripheral blood mononuclear cells (PBMC) were collected before the start, 4 weeks after the start, and after the end of IFN treatment and were stimulated with 2 peptides corresponding to core sequences, which were previously reported to have an HLA-A2 restricted-CTL epitopes. Cytolytic activity was determined by a standard 51Cr-release assay using allogenic HLA-matched EBV-transformed B lymphoblastoid cell lines (B-LCL). RESULTS: HCV-specific CTL responses were detected in 2 of the 8 patients before treatment with IFN-beta. One of 2 patients was not observed HCV-specific CTL responses after 4 weeks of IFN-beta treatment, however these two patients showed CTL responses at the end of IFN-beta treatment, and finally HCV-RNA was negative. In addition, HCV-specific CTL responses were observed in 4 patients after 4 weeks of IFN-beta treatment. Three of these 4 patients showed CTL responses only at 4 weeks after IFN-beta treatment. However, there were no differences between clinical parameters or between IFN efficacy in HCV specific CTL response-positive (n = 4) and -negative (n = 4) patients at 4 weeks after the start of IFN-beta treatment. CONCLUSIONS: These findings suggest that there are few relations between peripheral HCV-specific CTL response and clinical response to IFN therapy in patients with chronic hepatitis C, although IFN enhances the host immune response against HCV synergistically with antiviral activities.  相似文献   
55.
Glucocorticoid-induced osteoporosis: pathogenesis and management   总被引:4,自引:0,他引:4  
Glucocorticoid- (GC-) induced osteoporosis and an increased risk of fractures are one of the most serious problems for patient using long-term GC therapy, such as those with rheumatoid arthritis, autoimmune diseases, inflammatory bowel diseases, bronchial asthma, and chronic lung diseases. GCs are known to affect both bone formation and resorption. In rheumatoid arthritis, the etiology of bone loss is multifactorial, including local inflammation around joints, release of bone-absorbing cytokines, physical inactivity, and malnutrition, in addition to the use of GC. Two guidelines have been published, by the American College of Rheumatology Task Force in 1966 and by the UK Consensus Group in 1998. Both guidelines recommend that patients receiving GC therapy at doses of 7.5 mg/day of prednisolone or more for 6 months or longer should have their bone mineral density measured and begin preventive therapies. Calcium and vitamin D supplements, sex hormone replacement, and weight-bearing exercise are the first-line therapies. For patients who are unable to take sex hormone replacement therapy (HRT), bisphosphonates are recommended by both guidelines. In this article, we briefly summarize the pathogenesis of GC-induced osteoporosis and its prevention and treatment. Received: April 7, 2000  相似文献   
56.
To update the evidence on the association between smoking and mortality, we analyzed data from a population-based prospective study in Japan. In total, 19950 men and 21534 women aged 40 - 59 who reported their smoking history and had no serious disease at baseline survey were followed. During 1990 - 1999, 1014 men and 500 women died. Smokers were associated with an unhealthy lifestyle. Relative risks (RRs) for selected cause of death due to smoking were slightly attenuated by adjusting for possible confounding factors. Age- and area-adjusted RRs of male current smokers compared with never smokers were 1.66 (95% confidence intervals (CI): 1.40, 1.95) for all causes, 1.69 (1.31, 2.18) for all cancers, 1.67 (1.20, 2.34) for all circulatory system disease, and 1.63 (1.24, 2.15) for other causes, while those of females were 2.03 (1.52, 2.73), 2.06 (1.35, 3.15), 2.99 (1.75, 5.11), 1.31 (0.69, 2.51), respectively. After adjusting for multivariate variables, the corresponding RRs of male smokers were 1.55 (1.29, 1.86), 1.61 (1.20, 2.15), 1.41 (0.97, 2.03), and 1.61 (1.17, 2.19), against 1.89 (1.36, 2.62), 1.83 (1.14, 2.95), 2.72 (1.45, 5.07), and 1.39 (0.71, 2.73) for females. Twenty-two percent of death from all causes, 25% of all cancer, and 17% of all circulatory system disease deaths, could be attributed to cigarette smoking in males, and 5%, 4%, and 11% in females, respectively. Cumulative dose as indicated by pack-years was clearly associated with cancer death. These findings provided information as to the quantitative risk for premature death due to smoking among middle-aged Japanese men and women, and showed that the elevated risk was not explained by the unhealthy lifestyle of smokers.  相似文献   
57.
The hypothesis, that a blood vessel's phenotype is determined by the tissue it vascularizes and not by the vessel's source, does not hold for tissue beyond a certain period of development. In mature skeletal muscle grafted to choroid plexus of adult and 2-week-old rats, some vessels were choroidal or fenestrated (FV) rather than, according to the hypothesis, continuous (CV), like those of muscle. In E14 fetal muscle placed on the choroid plexus, 80% of the grafts' capillaries were CV, like those of muscle. Most choroidal FV that entered the grafts were apparently changed to CV. By E16, about 70% of the graft vessels remained as FV rather than being converted. Thus, FV were changed to CV by a hypothetical conversion factor made, apparently, by E14 grafts but not by E16 grafts. In grafts from [3H]thymidine-labeled donors, an appreciable number of CV in E14 grafts were identified as intrinsic to the muscle. When hosts were labeled to verify the origin of FV in their nonlabeled donor grafts, only a few FV, to date, were tagged. The FV must have come from host choroid plexus, the only available source of graft FV. Vascular endothelial growth factor (VEGF) might convert CV into FV, yet VEGF and the mRNA for its receptor were present in choroid plexus but not in the grafts. Therefore, VEGF is not a conversion factor. The purported factor that changes FV to CV may be expressed in E14 muscle grafts but diminishes by fetal age E16 and beyond.  相似文献   
58.
Objective To investigate the association of body mass index (BMI) or body height with colorectal cancer incidence in a population-based prospective study.Methods We identified 986 (626 men and 360 women) newly diagnosed cases of colorectal cancer during the 9.4-year follow-up of a cohort consisting of 102,949 (49,158 male and 53,791 female) middle-aged and elderly Japanese.Results Lower BMI groups (lower than 23) were not associated with colorectal cancer compared with the 23–24.9 BMI group. Any categories of 25–26.9, 27–29.9, or 30 or more BMI were associated with an increased risk of colorectal cancer compared with the lower than 25 BMI (RR, 1.2 for 25–26.9, 1.4 for 27–29.9, and 1.5 for 30 or more; p for trend, 0.004) in men. These associations were more evident only in invasive-type cancer analysis. BMI was not associated with the risk of colorectal cancer in women. No significant association with height was obtained for either men or women.Conclusions The association of BMI with colorectal cancer was confirmed in a Japanese population as well as Western populations. Only invasive-cancer analysis suggested that BMI was important for tumor growth and proliferation. Approximately 6.7% of colorectal cancer was attributable to a BMI of 25 or higher in middle-aged and elderly Japanese men.  相似文献   
59.
We investigated NY-ESO-1 and LAGE-1a mRNA expression in normal tissues and various types of cancer by quantitative real-time RT-PCR. In addition to their high expression in the testis, we observed a low expression of NY-ESO-1 mRNA in the placenta, pancreas and liver, and no expression in 12 other normal tissues. We also observed a low expression of LAGE-1a mRNA in the placenta and ovary, and marginal expression in 13 other normal tissues. In contrast to the previous finding that NY-ESO-1 and LAGE-1a mRNAs were mostly co-expressed in solid tumors, we found an independent expression of NY-ESO-1 and LAGE-1a mRNAs. NY-ESO-1 mRNA expression was mostly associated with LAGE-1a mRNA expression in esophageal and liver cancers, but not in prostate cancer. Immunohistochemistry (IHC) using NY-ESO-1-specific ES121 mAb showed that NY-ESO-1 protein was detected in 6 of 9 and 3 of 10 NY-ESO-1 mRNA-positive specimens from esophageal and liver cancers, respectively. NY-ESO-1 protein expression was correlated with the copy numbers of NY-ESO-1 mRNA. IHC was also performed using ES121 mAb and B9.8 mAb recognizing both NY-ESO-1 and LAGE-1a in 4 esophageal and 6 liver cancer specimens preferentially expressing LAGE-1a mRNA. B9.8-specific staining was observed weakly and focally in one liver cancer specimen expressing >10(5) copies of LAGE-1a mRNA.  相似文献   
60.
A 41-year-old woman presented with a small occipital arteriovenous malformation (AVM) manifesting as headache. Cerebral angiography showed an AVM in the right occipital lobe fed by the right temporooccipital artery and draining into the superior sagittal sinus and right transverse sinus. Single photon emission computed tomography showed the steal phenomenon in the ipsilateral temporal cortex fed by the main feeding artery preoperatively, and hyperperfusion in the same cortex after removal of the AVM. Postoperative systolic blood pressure was maintained between 100 and 120 mmHg to avoid disastrous hemorrhagic complications. Cerebral blood flow evaluation before and after surgery is important to avoid postoperative disastrous complications even in patients with small AVM.  相似文献   
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