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31.
初级卫生保健无论在发达国家还是发展中国家都是卫生保健系统的一个明显特征。根据Starfield提出的不同国家初级卫生保健发展状况要素,对中德两国的初级卫生保健人员、资金来源和支付方式、服务方式及改革和发展趋势等进行比较研究。通过分析借鉴德国的初级卫生保健和全科医生制度,探讨我国初级卫生保健的实现途径,以促进卫生体制的深化改革。  相似文献   
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To avoid increasing the risk of thromboembolic events, it is recommended that treatment with anticoagulants should be continued during dentoalveolar operations. We have evaluated the incidence of bleeding after dentoalveolar operations in a prospective study of 206 patients, 103 who were, and 103 who were not, taking anticoagulants. Seventy-one were taking thrombocyte aggregation inhibitors and 32 vitamin K antagonists. Patients were treated according to guidelines developed at the Academic Centre for Dentistry Amsterdam (ACTA), The Netherlands. The operations studied included surgical extraction (when the surgeon had to incise the gingiva before extraction), non-surgical extraction, apicectomy, and placement of implants. Patients were given standard postoperative care and those taking vitamin K antagonists used tranexamic acid mouthwash postoperatively.  相似文献   
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We conducted a weight-of-evidence (WoE) analysis to assess whether the current body of research supports a causal relationship between long-term ozone exposure (defined by EPA as at least 30 days in duration) at ambient levels and cardiovascular (CV) effects. We used a novel WoE framework based on the United States Environmental Protection Agency's National Ambient Air Quality Standards causal framework for this analysis. Specifically, we critically evaluated and integrated the relevant epidemiology and experimental animal data and classified a causal determination based on categories proposed by the Institute of Medicine's 2008 report, Improving the Presumptive Disability Decision-making Process for Veterans. We found that the risks of CV effects are largely null across human and experimental animal studies. The few positive associations reported in studies of CV morbidity and mortality are very small in magnitude, mainly reported in single-pollutant models, and likely attributable to bias, chance, or confounding. The few positive effects in experimental animal studies were observed mainly in ex vivo studies at high exposures, and even the in vivo findings are not likely relevant to humans. The available data also do not support a biologically plausible mechanism for the effects of ozone on the CV system. Overall, the current WoE provides no convincing case for a causal relationship between long-term exposure to ambient ozone and adverse effects on the CV system in humans, but the limitations of the available studies preclude definitive conclusions regarding a lack of causation; thus, we categorize the strength of evidence for a causal relationship between long-term exposure to ozone and CV effects as “below equipoise.”  相似文献   
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PURPOSE: The aim of this study was to determine the value of DCC (deleted in colorectal cancer) protein for predicting metachronous distant metastases after curative surgery for rectal cancer. The DCC protein—for which a gene has been located on chromosome 18q—has recently been reported to have a prognostic value in colorectal cancer. This finding might have implications for treatment of International Union Against Cancer Stage II rectal carcinoma, in which distant metastases will develop in 14 percent of patients despite optimal surgery. METHODS: Paraffin-embedded tissues from 85 patients who developed distant metastases, but no local recurrence, after curative surgery for rectal cancer were matched with 85 samples from patients who remained disease-free. Matching criteria were tumor stage, age, gender, and date of surgery. Expression of DCC protein was assessed using immunohistochemistry. End points of follow-up were recurrence of disease and death. Mean follow-up was 9.6 years. No patient received either local or systemic adjuvant therapy. RESULTS: The DCC protein was found to be expressed in 64.9 percent of tumor samples. Nonexpression of DCC protein had an negative influence on survival (P=0.03). For all tumor stages together, sensitivity of the test for subsequent occurrence of distant metastases was 42 percent and specificity was 71 percent. In Stage II cancers, the positive predictive value was 19 percent, and the negative predictive value was 88 percent. CONCLUSIONS: Our results confirm that DCC protein is a useful prognostic marker in patients with rectal carcinomas, but the positive predictive value of DCC protein for occurrence of metachronous metastases does not appear to be sufficient to justify adjuvant therapeutic measures in Stage II rectal cancer.  相似文献   
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Expression of nm23-H1 predicts lymph node involvement in colorectal carcinoma   总被引:13,自引:0,他引:13  
PURPOSE: Reduced expression of the metastasis suppressor gene nm23-H1 has previously been correlated with high tumor metastatic potential and fatal clinical outcome in some tumors (e.g.,breast). For colorectal carcinomas, the findings are equivocal. METHODS: We have used a monoclonal antibody against nm23-H1 to investigate the expression in colorectal carcinomas at the time of primary curative surgery (RO resection) to assess if there was any relation between nm23-H1 expression and stage or histologic grade at the time of primary tumor removal. RESULTS: Of 100 colorectal carcinomas studied (Stages I, II, and III according UICC, all resected curatively), nm23-H1 immunoreactivity was weak in 41 (41 percent), moderate in 24 (24 percent), and strong in 35 (35 percent) cases. The grade of positivity against nm23-H1 was significantly lower in advanced stages of the disease (Stages II or III) (P < 0.001, chi-squared=52.8). In tumors with low or weak immunoreactivity against nm23-H1, frequency of lymph node metastases was significantly higher compared with those with moderate or strong staining (P < 0.001; chi-squared=50.58). Therefore, with a sensitivity of 93 percent and a specificity of 58 percent, low nm23-H1 immunoreactivity of the primary tumor, assessed at the time of surgery, is an indicator of the presence of lymph node metastases. CONCLUSIONS: Immunohisto-chemical evaluation of nm23-H1 in the primary tumor or in a biopsy is a useful predictor of stage of disease and presence of lymph node metastases in colorectal carcinomas and may have clinical significance,e.g.,in predicting optimal therapeutic regimes.  相似文献   
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OBJECTIVE: Double blind studies were conducted with the anti-CD4 monoclonal antibody (Mab) keliximab in patients with active, stable rheumatoid arthritis (RA), to confirm preliminary evidence of efficacy and safety from open. uncontrolled studies. METHODS: We enrolled 136 and 186 patients into 2 consecutive, randomized, double blind trials, with similar populations [apart from inclusion of disease modifying antirheumatic drug (DMARD)-na?ve patients in Study 2]. Patients received 4 weeks intravenous placebo or keliximab [40, 80, 120, or 140 mg twice weekly (bw), or 240 mg once weekly (ow)].The primary endpoint was the American College of Rheumatology (ACR) 20 response criteria, one week after the end of treatment. RESULTS: ACR 20 response rates in Study I were 19%, 42%, 51%*, and 69%* (*p < 0.05 compared to placebo), with placebo, 40, 80, or 140 mg keliximab bw, respectively. The response rates in Study 2 were 30%, 39%, 46% and 47% with placebo, 80 or 120 mg bw, or 240 mg keliximab ow, respectively. In the 2 studies, there was a dose dependent increase in peripheral blood CD4+ T cell coating with keliximab, but a different pattern of CD4 depletion was seen. While only 12% of keliximab treated patients in Study I had CD4 counts below 250 cells/mm3 at the end of the treatment period, 47% fell below this level in Study 2. Clinical response was not correlated with CD4 depletion, but was correlated with CD4+ T cell coating with keliximab. CONCLUSION: Coating of peripheral blood CD4+ T cells with keliximab, but not CD4 depletion, is a determinant of clinical response.  相似文献   
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