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BACKGROUND: Heart disease is a major cause of illness and death in women. To understand better the role of estrogen in the treatment and prevention of heart disease, more information is needed about its effects on coronary atherosclerosis and the extent to which concomitant progestin therapy may modify these effects. METHODS: We randomly assigned a total of 309 women with angiographically verified coronary disease to receive 0.625 mg of conjugated estrogen per day, 0.625 mg of conjugated estrogen plus 2.5 mg of medroxyprogesterone acetate per day, or placebo. The women were followed for a mean (+/-SD) of 3.2+/-0.6 years. Base-line and follow-up coronary angiograms were analyzed by quantitative coronary angiography. RESULTS: Estrogen and estrogen plus medroxyprogesterone acetate produced significant reductions in low-density lipoprotein cholesterol levels (9.4 percent and 16.5 percent, respectively) and significant increases in high-density lipoprotein cholesterol levels (18.8 percent and 14.2 percent, respectively); however, neither treatment altered the progression of coronary atherosclerosis. After adjustment for measurements at base line, the mean (+/-SE) minimal coronary-artery diameters at follow-up were 1.87+/-0.02 mm, 1.84+/-0.02 mm, and 1.87+/-0.02 mm in women assigned to estrogen, estrogen plus medroxyprogesterone acetate, and placebo, respectively. The differences between the values for the two active-treatment groups and the value for the placebo group were not significant. Analyses of several secondary angiographic outcomes and subgroups of women produced similar results. The rates of clinical cardiovascular events were also similar among the treatment groups. CONCLUSIONS: Neither estrogen alone nor estrogen plus medroxyprogesterone acetate affected the progression of coronary atherosclerosis in women with established disease. These results suggest that such women should not use estrogen replacement with an expectation of cardiovascular benefit.  相似文献   
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Rat pancreatic cells were dissociated using a combined enzyme and EDTA method, grown on a plastic surface and then overlayed with collagen gel. Our studies have shown that exocrine pancreatic cells grown in this way have the ability to rearrange themselves into a three-dimensional organoid structure in which well defined epithelial lumina have been identified by ultrastructural and light microscopic examination. This in vitro system has advantages in examining the cytodifferentiation of pancreatic cells and may be exploited in studying pancreatic carcinogenesis.  相似文献   
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IntroductionReoperative parathyroidectomy for persistent and recurrent primary hyperparathyroidism is dependent on radiology. This study aimed to compare outcomes in reoperative parathyroidectomy at a single centre using a combination of traditional and newer imaging studies.Materials and methodsRetrospective case note review of all reoperative parathyroidectomies for persistent and recurrent primary hyperparathyroidism over five years (June 2014 to June 2019; group A). Imaging modalities used and their positive predictive value, complications and cure rates were compared with a published dataset spanning the preceding nine years (group B).ResultsFrom over 2000 parathyroidectomies, 147 were reoperations (101 in group A and 46 in group B). Age and sex ratios were similar (56 vs 62 years; 77% vs 72% female). Ultrasound use remains high and shows better positive predictive value (76% vs 57 %). 99mTc-sestamibi use has declined (79% vs 91%) but the positive predictive value has improved (74% vs 53%). 4DCT use has almost doubled (61% vs 37%) with better positive predictive value (88% vs 75%). 18F-fluorocholine positron emission tomography-computed tomography and ultrasound-guided fine-needle aspiration for parathyroid hormone are novel modalities only available for group A. Both carried a positive predictive value of 100%. Venous sampling with or without angiography use has decreased (35% vs 39%) but maintains a high positive predictive value (86% vs 91%). Cure rates were similar (96% vs 100%). Group A had 5% permanent hypoparathyroidism, 1% permanent vocal cord palsy and 1% haematoma requiring reoperation. No complications for group B.ConclusionOptimal imaging is key to good cure rates in reoperative parathyroidectomy. High-quality, non-interventional imaging techniques have produced a shift in the preoperative algorithm without compromising outcomes.  相似文献   
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The hospital transfusion service has always been at the heart of the blood component therapy chain. It has had the multiple roles of not only maintaining an inventory of a wide range of blood components, monitoring their storage conditions and ensuring compatibility when appropriate, but also being the source of expertise in transfusion medicine, and attempting to follow up any adverse consequences of transfusion. Hospital transfusion medicine has been seen essentially as a scientific and technical specialty with a minimal component of medical input. This is now changing and transfusion medicine is becoming an all embracing specialty where the hospital transfusion service still remains at the heart of transfusion medicine, but a much higher level of understanding is necessary at the clinical and consumer level.  相似文献   
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Although Mycobacterium avium complex (MAC) is the most common opportunistic bacterial infection in AIDS patients, epidural involvement is rare. A case of MAC spinal epidural abscess without vertebral osteomyelitis, that was continuous with presacral and bilateral piriformis muscle inflammation, is reported.  相似文献   
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