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71.
目的:探讨如达溃疡散对大鼠乙酸性胃溃疡的作用及对其血清促胃液素(gastrin)含量的影响.方法:采用乙酸法复制胃溃疡模型,将大鼠随机分为对照组、如达溃疡散组、雷尼替丁组,观察如达溃疡散对大鼠胃溃疡的作用,并检测其对大鼠血清中促胃液素含量的影响.结果:与对照组相比,如达溃疡散能明显抑制溃疡的发生,抑制血清促胃液素含量.结论:如达溃疡散具有抗胃溃疡的作用,其作用机理可能是通过抑制促胃液素释放,进一步减少胃酸分泌来实现的. 相似文献
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Straus WL Eisen GM Sandler RS Murray SC Sessions JT 《The American journal of gastroenterology》2000,95(2):479-483
OBJECTIVE: The severity of Crohn's disease (CD) has been reported to be greater in blacks than in whites. This possible disparity may be due, in part, to differences between these groups in health care utilization and accessibility. To explore these issues, we conducted a multicenter survey of patients with CD. METHODS: One-hundred and forty-five blacks with CD, recruited from four teaching hospitals and five private practices, and identified by medical record review or ICD-9 code, were enrolled and matched to 407 whites with CD (by age, gender, and practice type [teaching vs. private practice setting]). Participants were interviewed regarding medical history, health status, personal health care practices during the preceding 5 yr, and beliefs regarding health care in the general population. RESULTS: Blacks and whites were similar with respect to age of CD onset, lag in time to diagnosis, and number of gastrointestinal (GI)-related hospitalizations and surgeries. Medication usage patterns were also similar in the two groups. Quality of life, measured by SF-36, was lower in all categories for blacks, compared with whites. Blacks were more likely to have had to stop work (p<0.01) and have lost more work days (p<0.01) than were whites. Whites were more likely to have health insurance and be able to identify a regular provider than were blacks. Blacks were more likely to report the following: receiving Medicaid; difficulty affording health care; delaying appointments due to financial concerns; difficulty traveling to their provider's office; and experiencing unreasonable delays at their provider's office. After adjusting for potential confounding variables, we found no differences between the groups, except for the number of days of work lost because of CD. CONCLUSIONS: These data suggest that black and white patients have similar reported disease presentations and course, and contrast with prior reports suggesting a more severe disease course among black patients. Although the disease itself appears similar, there were numerous reported differences between the races in health care utilization practices and in disease impact upon daily activities. We suggest that apparent disparities in CD according to race are actually due to social and economic factors, and not to the disease itself. 相似文献
75.
E Somekh D G Tedder A Vafai J G Assouline S E Straus C L Wilcox M J Levin 《Pediatric research》1992,32(6):699-703
A potential in vitro model of varicella-zoster virus (VZV) latency was developed. Dissociated human dorsal root ganglion cultures were infected with VZV and maintained for 1 wk in the presence of bromovinyl arabinosyl uracil, a potent inhibitor of VZV. Seven to 21 d after removing the inhibitor (> or = 14 d after infection), the cells were trypsinized, passed to monolayers of human embryonic lung fibroblasts, and observed for VZV reactivation as indicated by typical cytopathic effects and the appearance of VZV antigens. VZV reactivated from 56% of the cultures containing both neurons and satellite cells but not from cultures specifically enriched for either neurons, satellite cells, or ganglion-derived fibroblasts. The failure to isolate VZV from cell suspensions that were sonicated before cocultivation with fibroblasts indicated that infectious VZV was not present before reactivation. Moreover, immunohistochemical and immunoprecipitation studies revealed no VZV-specific antigens in any cultures before the reactivation stimulus. VZV antigens were detected after trypsinization and cocultivation. These findings suggest that cultures containing both neurons and satellite cells provide a model system for VZV persistence that possesses many properties of a latent infection. 相似文献
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Regular physical activity has both short- and long-term health benefits in adults. No study has investigated childhood determinants of adult physical activity patterns, however. In a nonconcurrent prospective study, the physical activity levels of 453 young men, 23 to 25 years of age, were compared with their physical fitness test scores as children (10 to 11 years of age and 15 to 18 years of age). The physically active adults had significantly better childhood physical fitness test scores than did the inactive adults. In 224 children, 2 years of fitness test results were available. The risk of physical inactivity in young adulthood was linearly related to the number of low scores on the 548.6-m (600-yd) run and sit-ups tests as children (P less than .001). In stepwise multivariate discriminant analysis, the childhood 548.6-m run score was the best discriminator between currently physically active and inactive adults. Reported parental encouragement of exercise, level of education, participation in organized sports after high school, and reported spousal encouragement of exercise also contributed significantly to the discriminant function. These results demonstrate that physical fitness testing in boys facilitates the identification of those at increased risk of becoming physically inactive young adults. 相似文献
78.
The cost of chronic benign spinal pain is large and growing. The costs of interventional treatment for spinal pain were at a minimum of $13 billion (U.S. dollars) in 1990, and the costs are growing at least 7% per year. Medical treatment of chronic pain costs $9000 to $19,000 per person per year. The costs of interventional therapy is calculated. Methods of evaluating differential treatments in terms of costs are described. Cost-minimization versus cost-effectiveness approaches are described. Spinal cord stimulation and intraspinal drug infusion systems are alternatives that can be justified on a cost basis. Cost minimization analysis suggests that epidural injections under fluoroscopy may not be justified by the current literature. 相似文献
79.
Whereas other components of the National Institutes of Health support the discovery and subsequent development of novel chemical entities into drugs, the National Center for Complementary and Alternative Medicine (NCCAM) studies complex natural products that are marketed as dietary supplements. This article contrasts the regulatory framework for dietary supplements and drugs, outlines the challenges of evaluating dietary supplements for safety and clinical effectiveness, and describes the evolving drug model for botanicals. 相似文献
80.
Autoimmune lymphoproliferative syndrome arises early in childhood in people who inherit mutations in genes that mediate lymphocyte apoptosis, or programmed cell death. In the immune system, antigen-induced lymphocyte apoptosis maintains immune homeostasis by limiting lymphocyte accumulation and minimizing reactions against self-antigens. In autoimmune lymphoproliferative syndrome, defective lymphocyte apoptosis manifests as chronic, nonmalignant adenopathy and splenomegaly; the expansion of an unusual population of CD4-CD8- T cells; and the development of autoimmune disease. Most cases of autoimmune lymphoproliferative syndrome involve heterozygous mutations in the lymphocyte surface protein Fas (CD95, Apo1) that impair a major apoptotic pathway. Prospective evaluations of patients and their families have revealed an ever-expanding spectrum of autoimmune lymphoproliferative syndrome and its major complications. 相似文献