Reperfusion injury delays healing of intestinal anastomosis in a rat

This SAEM position paper clarifies the role of emergency medicine in health care delivery. It builds upon the working definition of emergency medicine developed by the American College of Emergency Physicians in 1994 by describing the health care role of emergency physicians (EPs). EPs are first-contact providers who care for all patients regardless of age, gender, time of presentation, or ability to pay. They remain the only continuously accessible specialty for patients seeking help and solace in the health care system. They are an essential link in the health care continuum between primary care physicians, specialists, the out-of-hospital system, the patient, inpatient services, and communication services. The EP's role is in organizing and monitoring the emergency care delivery system. Part of this role is to better align the health care provider training and ability with the specific medical needs of a patient. The emergency health care system remains the essential medical safety net for all individuals needing care in this country.     

Crystal structure of TNF-alpha mutant R31D with greater affinity for receptor R1 compared with R2

Crystal structures have been determined of recombinant human tumor necrosis factor-alpha (TNF-alpha) and its R31D mutant that preferentially binds to TNF receptor R1 with more than seven times the relative affinity of binding to receptor R2. Crystals of the wild-type TNF were of space group P4(1)2(1)2 and had unit cell dimensions of a = b = 94.7 and c = 117.4 A. Refinement of the structure gave an R-factor of 22.3% at 2.5 A resolution. The crystals of TNF R31D mutant diffracted to 2.3 A resolution, and were of identical space group to the wild type with unit cell dimensions of a = b = 95.4 and c = 116.2 A, and the structure was refined to an R-factor of 21.8%. The trimer structures of the wild-type and mutant TNF were similar with a root mean square (r.m.s.) deviation of 0.56 A for Calpha atoms; however, the subunits within each trimer were more variable with an average r.m.s. deviation of 1.00 A on Calpha atoms for pairwise comparison of subunits. Model complexes of TNF with receptors R1 and R2 have been used to predict TNF-receptor interactions. Arg31 in all three subunits of wild-type TNF is predicted to form an ionic interaction with the equivalent glutamic acid in both receptors R1 and R2. Asp31 of the TNF R31D mutant is predicted to interact differently with the two receptors. The side chain of Asp31 in two subunits of the TNF mutant is predicted to form hydrogen bond interactions with Ser59 or Cys70 of R1, while it has no predicted interactions with R2. The loss of three strong ionic interactions of Arg31 and the electrostatic repulsion of Asp31 with Glu in the receptors is consistent with the reduced binding of the R31D mutant to both receptors relative to wild-type TNF. The replacement of these ionic interactions by two weaker hydrogen bond interactions between Asp31 of the R31D mutant and R1, compared with no interactions with R2, is in agreement with the observed preferential binding of the R31D mutant to R1 over R2. Analysis of the structure and function of receptor-discriminating mutants of TNF will help understand the biological role of TNF and facilitate its use as an antitumor agent.      

三大原则激活数据红利

如今,各国政府都在寻找可以通过少量投入实现强大新功能的科技。只要有追求创新的精神和持之以恒的努力,大多数城市都可以实现可持续发展的智能技术解决方案,从而降低成本,提高市政服务水平,改善市民的生活质量。微软委托IDC进行的一项最新研究指出,通过整合零散数据,采用新型数据分析工具,并向更多人传递有用的洞察,全球各国的政府机构在未来四年内从数据挖掘中获得的数据红利将高达2060亿美元,并且越早采用,收益越大。     

如何有效控制存储成本

导读 目前,控制合规成本仍是企业的工作重点之一。其中的难点在于如何在恰当的时间将正确的“内容”保存在适宜的地方。依据传统的做法,企业在对数据归档时只是一味地对数据无限制的存储,无法经济高效地从长远解决数据保留问题。     

新品导购笔记本电脑

LG M1●处理器:Intel Core Duo T2300(1.6GHz,2M二级缓存)●显卡:Intel GMA950●屏幕:15英寸液晶炫丽屏●内存:512MB DDR2●硬盘:80G●光驱:COMBO价格:12999元M1外壳采用宝石蓝,乳白色的机身在两层幽蓝的映衬下更显细腻,二者结合在一起则在商务气息之中增添了一份时尚韵味,M1机身使用了斜角设计,前后两面柔滑的斜边将显示器单元托起,顶盖也以同样圆润的曲线顺滑下来,在机器前端形成一个赏心悦目的线条组合。而这款产品还装备了指纹验证装置,在安全性方面能够给用户更安心的数据保护功能。明基S61●处理器:Intel Core Duo T2300…     

智能手机的7年之痒：迅速PC化

从苹果2007年1月发布iPhone以来，智能手机产业正好过去7个年头，坐稳山头没多久的三星、苹果和“中华酷联”们，又要面对当年功能机前辈们的困境了吗     

Respiratory symptoms and pulmonary function in coal miners: looking into the effects of simple pneumoconiosis

Most soil quality guidelines do not distinguish among the various forms of metals in soils; insoluble, nonreactive, and nonbioavailable forms are deemed as hazardous as highly soluble, reactive, and toxic forms. The objective of this study was to better understand the long-term effects of copper on microorganisms in relation to its chemical speciation in the soil environment. Carbon mineralization processes and the global structure of different microbial communities (fungi, eubacteria, actinomycetes) are still affected after more than 50 years of copper contamination in 20 soils sampled from two different agricultural sites. The microbial respiration lag period (LP) preceding the beginning of mineralization process increases with the level of soil copper contamination and is not significantly affected by other environmental factors such as soil pH and soil organic matter (SOM) content. The total copper concentration showed the best correlation with the LP when each site is considered separately. However, when considering the whole set of data, soil solution free Cu2+ activity (pCu2+) is the best predictor of Cu toxicity determined by LP (quite likely because pCu2+ integrates the soil physicochemical variability). The maximum mineralization rate (MMR), even if well correlated with the pCu2+, appears not to be a good biomonitor of copper contamination in soils since it is highly sensitive to soil characteristics such as SOM content. This study emphasizes the importance of the physicochemical properties of the environment on soil heavy metal toxicity and on soil toxicological measurements. These properties must be characterized in soil toxicological studies with respect to (1) their interactions with heavy metals, and (2) their direct impact on the selected biological test. The measurement of pCu2+ to characterize the level of soil contamination and of lag period as a bioindicator of metal effects in the soil are recognized as useful tools for the evaluation of the biological quality of soils.     

决战视觉品质，打造2006宽屏年——名牌宽屏液晶完全采购宝典

●宽屏液晶的市场新走势 2005年，大多数17寸液晶价格降到了2000元内．迅速成为显示器市场的主流。2006年对于许多要求高的用户来说，17寸液晶已经成为过去式了，他们需要更大更宽的液晶来享受“大面子”的魅力，市场上便应运而生出现了数款19寸以上的宽屏液晶。     

Randomised trial comparing hysterectomy with endometrial ablation for dysfunctional uterine bleeding: psychiatric and psychosocial aspects

OBJECTIVE: To compare in psychiatric and psychosocial terms the outcome of hysterectomy and endometrial ablation for the treatment of dysfunctional uterine bleeding. DESIGN: Prospective randomised controlled trial. SETTING--Obstetrics and gynaecology department of a large teaching hospital. SUBJECTS: 204 women with dysfunctional bleeding for whom hysterectomy would have been the preferred treatment were recruited over 24 months and randomly allocated to hysterectomy (99 women) or to hysteroscopic surgery (transcervical resection (52 women) or laser ablation (53 women). MAIN OUTCOME MEASURES: Mental state, martial relationship, psychosocial and sexual adjustment in assessments conducted before the operation and one month, six months, and 12 months later. RESULTS: Both treatments significantly reduced the anxiety and depression present before the operation, and there were no differences in mental health between the groups at 12 months. Hysterectomy did not lead to postoperative psychiatric illness. Sexual interest after the operation did not vary with treatment. Overall, 46 out of 185 (25%) women reported a loss sexual interest and 50 out of 185 (27%) reported increased sexual interest. Marital relationships were unaffected by surgery. Personality and duration of dysfunctional uterine bleeding played no significant part in determining outcome. CONCLUSIONS: Hysteroscopic surgery and hysterectomy have a similar effect on psychiatric and psychosocial outcomes. There is no evidence that hysterectomy leads to postoperative psychiatric illness.     

Surgeons--the presidents and commanders of the former Medical Surgical Academy--of the Military Medical Academy

BACKGROUND: To examine the prevalence of atrial fibrillation (AF) in cardiopathic patients with hyperthyroidism. METHODS: The data concerning the patients had been derived from registers of the Laboratory of Radioimmunoassay where cardiopathic patients' blood samples were referred from the Cardiology Unit to evaluate thyroid function, consecutively from January 1992 to December 1997. Of the 443 patients, 303 (68.4%) were classified as being euthyroid, 23 (5.2%) hypothyroid, 117 (26.4%) hyperthyroid. Thyroid function was diagnosed clinically and confirmed by serum TSH and free thyroid hormone (FT3, FT4), levels. RESULTS: Among hyperthyroid patients, the more frequent arrhythmia was AF (54.7%). After excluding from the study those hyperthyroid patients with rheumatic disease, hypertension, myocardial infarction, 37 hyperthyroid patients were selected; 18 (48.6%), (mean age 63.4 +/- 10.8 yrs), showed sinus rhythm and 19 (51.4%), (mean age 66.0 +/- 12.1 yrs), showed AF. FT3 and FT4 were higher in patients with AF than in those without AF, whereas TSH was not significantly different between the groups. Left ventricular (LV) mass index was significantly increased in hyperthyroid women with AF compared with hyperthyroid women without AF (109.80 +/- 22.33 g/m2 vs 84.50 +/- 6.20 g/m2; p < 0.005). A significant correlation was found between FT3 levels and LV mass index in the hyperthyroid women with and without AF (r = 0.77; p < 0.001). CONCLUSIONS: In this study the prevalence of AF is 51.4% in hyperthyroid patients. FT3 is higher in patients with AF than in those without AF. Finally, the correlation between FT3 and LV mass index suggests that cardiac hypertrophy is associated with thyroid hyperfunction.