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41.
BACKGROUND: There is mounting evidence that low-intensity oral anticoagulation is effective, particularly in primary prevention of thrombosis, with important implications for safety and the practicalities of using warfarin. Because it is desirable to know possible benefits for different indications so that optimal therapy can be administered in as wide a range of conditions as possible, we analyzed data from the Thrombosis Prevention Trial, a factorial trial that compared treatment with low-intensity, dose-adjusted warfarin and low-dose aspirin separately and together, to determine the minimum effective intensity of oral anticoagulation in the primary prevention of coronary heart disease. METHODS: The international normalized ratio (INR) most recent to an event and overall time at each INR were used to calculate the INR-related event rate for coronary events, strokes, and major and minor bleeding episodes in 2545 men receiving warfarin with or without aspirin (75 mg/d) and followed up for a total of 9952 person-years. RESULTS: Compared with placebo, warfarin alone at a dose that maintained the INR at 1.4 or more significantly reduced the risk of a coronary event by 47% (95% confidence interval, 4%-70%; P =.03), whereas the risk of a coronary event was not reduced at INRs below 1. 4. Coronary events, strokes, and major bleeding episodes combined were significantly reduced by 45% (95% confidence interval, 9%-67%; P =.02) in the warfarin group compared with the placebo group when the INR was 1.4 or more. Minor bleeding episodes increased as the INR rose above about 2.0. No significant association of INR with coronary events was observed with combined warfarin and aspirin, possibly reflecting the small number of such events that occurred in this group, therefore limiting the power to detect an association with INR. CONCLUSIONS: Warfarin alone is effective in the primary prevention of coronary heart disease when the dose is adjusted to maintain an INR of 1.4 or more. The results add to the evidence that low-intensity, dose-adjusted oral anticoagulation is effective for a range of conditions.  相似文献   
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Emerging evidence to support the use of endothelial progenitor cells (EPCs) for angiogenic therapies or as biomarkers to assess cardiovascular disease risk and progression is compelling. However, there is no uniform definition of an EPC, which makes interpretation of these studies difficult. Although hallmarks of stem and progenitor cells are their ability to proliferate and to give rise to functional progeny, EPCs are primarily defined by the expression of cell-surface antigens. Here, using adult peripheral and umbilical cord blood, we describe an approach that identifies a novel hierarchy of EPCs based on their clonogenic and proliferative potential, analogous to the hematopoietic cell system. In fact, some EPCs form replatable colonies when deposited at the single-cell level. Using this approach, we also identify a previously unrecognized population of EPCs in cord blood that can achieve at least 100 population doublings, replate into at least secondary and tertiary colonies, and retain high levels of telomerase activity. Thus, these studies describe a clonogenic method to define a hierarchy of EPCs based on their proliferative potential, and they identify a unique population of high proliferative potential-endothelial colony-forming cells (HPP-ECFCs) in human umbilical cord blood.  相似文献   
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National Comprehensive Cancer Network (NCCN) guidelines for female breast cancer treatment and surveillance are well established, but similar guidelines on male breast cancers are less recognized. As an NCCN institution, our objective was to examine practice patterns and follow-up for male breast cancer compared to established guidelines for female patients. After Institutional Review Board approval, a prospective breast database from 1990 to 2009 was queried for male patients. Medical records were examined for clinico-pathological factors and follow-up. The 5-year survival rates with 95% confidence intervals were estimated using Kaplan-Meier method and Greenwood formula. Of the 19,084 patients in the database, 73 (0.4%) were male patients; 62 had complete data. One patient had bilateral synchronous breast cancer. The median age was 68.8 years (range 29-85 years). The mean/median invasive tumor size was 2.2/1.6 cm (range 0.0-10.0 cm). All cases had mastectomy (29 with axillary node dissection, 23 with sentinel lymph node biopsy only, 11 with sentinel node biopsy followed by completion axillary dissection). Lymph node involvement occurred in 25/63 (39.7%). Based on NCCN guidelines, chemotherapy, hormonal therapy, and radiation are indicated in 34 cases, 62 cases, and 14 cases, respectively. Only 20/34 (59%) received chemotherapy, 51/62 (82%) received hormonal therapy, and 10/14 (71%) received post-mastectomy radiation. Median follow-up was 26.2 months (range: 1.6-230.9 months). The 5-year survival estimates for node positive and negative diseases were 68.5% and 87.5%, respectively (p = 0.3). Despite the rarity of male breast cancer, treatment options based on current female breast tumors produce comparable results to female breast cancer. Increased awareness and a national registry for patients could help improve outcomes and tailor treatment recommendations to the male variant.  相似文献   
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Detection of renal cell carcinoma (RCC) is increasing with the greater use of cross‐sectional imaging and up to two‐thirds of RCCs are discovered incidentally in asymptomatic patients. The traditional option of nephrectomy or partial nephrectomy may not always be appropriate. A minimally invasive treatment alternative is radiofrequency ablation (RFA). We retrospectively reviewed the RFA cases for renal tumours at our institution between January 2004 and June 2006. Thirteen RFA treatment sessions were conducted for 11 neoplasms in 11 patients. Mean patient age was 74.4 years (61–88 years). Imaging was carried out after ablation with a mean follow up of 8.0 months (2–26 months). No residual tumour was observed after the first RFA treatment in 82% of patients (nine of 11). Two patients required a second RFA treatment for residual (one) or recurrent tumour (one). RFA is emerging as a useful technique for treatment of small renal tumour. A number of short‐term studies reflect this, however, long‐term findings are still lacking.  相似文献   
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Background  

Chronic obstructive pulmonary disease (COPD) is a major but neglected public health problem. Currently 1.4% of the England population has a clinical diagnosis of COPD, but the true burden of the disease has not been known with certainty, as many cases remain undiagnosed.  相似文献   
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