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11.
The aim of this study was to determine whether reduced pulmonary function is an independent risk factor for peptic ulcer. Among 5933 Japanese men studied in Hawaii, 243 developed gastric ulcers and 99 developed duodenal ulcers 20 yr after an examination completed in 1968. The examination included measurement of forced expiratory volume in 1 s and a detailed smoking history. The percent predicted forced expiratory volume was significantly and inversely related to ulcer incidence, but not after adjustment for smoking or among those who had never smoked. Cigarettes were associated with increased ulcer risk in both stomach and duodenum but showed a dose-response in pack years only for gastric ulcer. We conclude that the association of reduced pulmonary function with peptic ulcer in the Japanese in Hawaii is largely attributable to smoking and that smoking is more strongly related to gastric than duodenal ulcer. The especially strong link between cigarettes and gastric ulcer suggests that decreased smoking or synchronous decrease in cigarette tar content may have contributed to the recent unexplained decrease in male gastric ulcer.  相似文献   
12.

Objective

Patients with chronic obstructive pulmonary disease (COPD) present systemic inflammation. Strenuous resistive breathing induces systemic inflammation in healthy subjects. We hypothesized that the increased respiratory load that characterizes COPD can contribute to systemic inflammation in these patients.

Patients and methods

To test this hypothesis, we compared leukocyte numbers and levels of circulating cytokines (tumor necrosis factor alpha [TNFα], interleukin-1β [IL-1β], IL-6, IL-8, and IL-10), before and 1 hour after maximal incremental inspiratory loading in 13 patients with stable COPD (forced expiratory volume in one second [FEV1] 29 ± 2.5% ref) and in 8 healthy sedentary subjects (FEV1 98 ± 5% ref).

Results

We found that: (1) at baseline, patients with COPD showed higher leukocyte counts and IL-8 levels than controls (p < 0.01); and, (2) one hour after maximal inspiratory loading these values were unchanged, except for IL-10, which increased in controls (p < 0.05) but not in patients with COPD.

Conclusions

This study confirms the presence of systemic inflammation in COPD, shows that maximal inspiratory loading does not increase the levels of pro-inflammatory cytokines (IL-1β, IL-8) in COPD patients or controls, but suggests that the former may be unable to mount an appropriate systemic anti-inflammatory response to exercise.  相似文献   
13.
ObjectiveTo determine the prevalence of Trichomonas vaginalis (T. vaginalis) in HIV/AIDS patients attending two different hospitals in southeast Nigeria.MethodsWe collected 970 urine samples from HIV/AIDS patients attending two different hospitals in southeast Nigeria. Samples were processed by microscopy and cultural methods.ResultsOut of the 970 screened, 355 (36.60%) were positive for T. vaginalis. Subjects with the least CD4+ count in the range of 40-140 cells/mL had the highest number of positive samples (180, 50.70%), while those in the range of 480-580 cells/mL had the least value (2, 0.56%). Those in the rural areas had a higher number of positive samples (155, 38.75%) than their urban counterparts (200, 35.09%) with respect to the total number examined in each group but this was not statistically significant (P>0.05). Out of the 355 positive cases, the university undergraduate students’ group had the highest percentage incidence of 53.00% followed by the low-income group with 47.08%.ConclusionsIt can be concluded that the occurrence of T. vaginalis increases with decrease in the CD4+ counts in HIV/AIDS patients in Nigeria. Since T. vaginalis may be an important cofactor in promoting the spread of HIV and, in some circumstances, may have a major impact on the epidemic dynamics of HIV, there is a need to take measures to check the spread of this parasitic infection.  相似文献   
14.
目的 探讨相对健康的中老年人血中糖化血红蛋白(HbAlc)含量对颈动脉硬化的影响.方法 从广州生物库队列中单纯随机抽样收集1863名年龄≥50岁的广州市居民的个人资料,问卷调查其病史、体格检查及测定血清空腹血糖、血脂、HbA1c的含量并应用彩色多普勒超声测量颈总动脉内膜-中层厚度(intima media thickness,IMT).在调整相关混染因素后,应用协方差分析进行连续变量分析.结果 (1)在调整年龄、性别和空腹血糖等因素后,平均颈总动脉IMT随HbA1c含量升高呈明显增加趋势(P=0.005).线性回归模型显示,在调整年龄、性别、吸烟状态、腰围、收缩压和舒张压、甘油三酯、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇和空腹血糖等潜在危险因素后,结果仍然显示HbA1c水平与平均颈总动脉IMT有明显的线性相关(回归系数为0.014,P=0.03);(2)经过调整多种潜在混杂因素后,与HbA1c理想组(HbA1c<6.5%)比较,良好组(HbA1c为6.5%~7.5%)和差组(HbA1c>7.5%)发生颈动脉硬化的比值比(95%置信区间)分别为1.62(1.10,2.38)和1.76(0.86,3.63),趋势检验(P=0.01).结论 相对健康的中老年人HbA1c含量升高是颈动脉硬化的独立危险因素之一,提示降低HbA1c水平对阻止或延缓颈动脉硬化的发生与发展有重要意义.  相似文献   
15.
Epstein-Barr virus (EBV) has recently been identified in the tumor cells of patients with gastric carcinoma. We tested pre-morbid serum samples from a carefully monitored cohort of Japanese men in order to investigate the possibility that patients with EBV-associated gastric cancer represent a sub-set of individuals with long-standing difficulties in appropriately managing EBV infection. From a serum bank, we obtained 108 samples derived from 54 patients destined to develop gastric adenocarcinoma and 54 controls. Samples were tested under code for antibodies to EBV-capsid antigen, early antigen and nuclear antigen. Individuals who were positive for IgA antibodies against EBV viral-capsid antigen (VCA) and IgG antibodies against the R component of EBV early antigen were at a 3.9-fold and 1.9-fold excess risk of disease, respectively. Antibody titers to EBV VCA were significantly higher in those destined to get EBV-associated gastric cancer than those subsequently developing non-EBV-associated gastric cancer or age-and-gender-matched controls. These findings suggest that the inability to control EBV infection on a long-term basis exists many years prior to the development of EBV-associated gastric cancer, and that EBV may play an etiologic role in this sub-set of malignancies.  相似文献   
16.
Although colonization with any Helicobacter pylori strain is associated with peptic ulcer, it is uncertain whether the risk is greater with cagA(+) or cagA(-) strains, which differ in their biology. A nested case-control study was done, based on a cohort of 5,443 Japanese-American men examined on the Hawaiian island of Oahu from 1967 to 1970. A total of 150 men with gastric ulcer, 65 with duodenal ulcer, and 14 with both diseases were identified. The authors matched the 229 cases with 229 population controls and tested their serum for immunoglobulin G antibodies to H. pylori and immunoglobulin G antibodies to the cagA product of H. pylori using enzyme-linked immunosorbent assays. Persons with H. pylori positivity had an odds ratio of 4.0 (95% confidence interval (CI): 1.9, 8.5) for gastric ulcer and 2.5 (95% CI: 0.8, 7.4) for duodenal ulcer. For CagA positivity, the odds ratios were 1.4 (95% CI: 0.9, 2.4) for gastric ulcer and 2.6 (95% CI: 1.1, 5.8) for duodenal ulcer. Subjects who were seropositive for both H. pylori and CagA had an odds ratio of 4.4 (95% CI: 1.8, 10.5) for gastric ulcer and 5.8 (95% CI: 1.1, 30.0) for duodenal ulcer. The results suggest that colonization with a cag(+) H. pylori strain elevates the risk beyond that of a cag(-) H. pylori strain for both gastric and duodenal ulcers.  相似文献   
17.
This article reviews the available data on prostate cancer in Japan compared with that in the United States, with emphasis on epidemiologic, pathologic, and molecular aspects. Previous studies have demonstrated ethnic/racial differences in the incidence of prostate cancer between the two countries. Recent investigations indicate that different genetic alterations or polymorphisms are related to carcinogenesis in the prostate. Comparative geographic-pathologic autopsy studies suggest that different promoting factors including genetic, epigenetic, and environmental influences may be responsible for ethnic variations in the postinduction progression of prostate cancer.  相似文献   
18.
19.
In this article, we survey the major p53 (TP53) alterations identified in gastric carcinomas and their precursors. These include p53 expression, mutations, and loss of heterozygosity (LOH). Not only are the various abnormalities summarized, but in addition there is a survey of the literature with respect to the impact of these changes on patient prognosis and treatment response. The majority of published studies involve the immunohistochemical detection of the protein. These use different antibodies, different detection techniques, and different methods of interpretation. Therefore not surprisingly, the results of many of the studies are contradictory with one another. Overall, however, it appears that p53 alterations occur early in the development of gastric carcinoma, being present even in the nonneoplastic mucosa and they increase in frequency as one progresses along the pathway of gastric carcinoma development. p53 immunoreactivity is seen in 17%-90.7% of invasive gastric carcinomas. p53 alterations occur much more commonly in proximal lesions than in distal ones, suggesting that the molecular events leading to the development of gastric carcinoma may be very different in proximal vs. distal tumors. p53 mutations occur in 0%-77% of gastric carcinomas. The mutations are distributed widely across the gene from exons 4-11 with hot spots of mutation at codons 175, 248, 273, 282, 245, and 213. G:C>A:T transitions at CpG sites are the commonest type of mutation. At least 60% of carcinomas with mutations also exhibit p53 LOH.  相似文献   
20.
BACKGROUND: Surgical resection of adenocarcinoma of the stomach is curative in less than 40 percent of cases. We investigated the effect of surgery plus postoperative (adjuvant) chemoradiotherapy on the survival of patients with resectable adenocarcinoma of the stomach or gastroesophageal junction. METHODS: A total of 556 patients with resected adenocarcinoma of the stomach or gastroesophageal junction were randomly assigned to surgery plus postoperative chemoradiotherapy or surgery alone. The adjuvant treatment consisted of 425 mg of fluorouracil per square meter of body-surface area per day, plus 20 mg of leucovorin per square meter per day, for five days, followed by 4500 cGy of radiation at 180 cGy per day, given five days per week for five weeks, with modified doses of fluorouracil and leucovorin on the first four and the last three days of radiotherapy. One month after the completion of radiotherapy, two five-day cycles of fluorouracil (425 mg per square meter per day) plus leucovorin (20 mg per square meter per day) were given one month apart. RESULTS: The median overall survival in the surgery-only group was 27 months, as compared with 36 months in the chemoradiotherapy group; the hazard ratio for death was 1.35 (95 percent confidence interval, 1.09 to 1.66; P=0.005). The hazard ratio for relapse was 1.52 (95 percent confidence interval, 1.23 to 1.86; P<0.001). Three patients (1 percent) died from toxic effects of the chemoradiotherapy; grade 3 toxic effects occurred in 41 percent of the patients in the chemoradiotherapy group, and grade 4 toxic effects occurred in 32 percent. CONCLUSIONS: Postoperative chemoradiotherapy should be considered for all patients at high risk for recurrence of adenocarcinoma of the stomach or gastroesophageal junction who have undergone curative resection.  相似文献   
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