首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   523篇
  免费   27篇
  国内免费   7篇
耳鼻咽喉   1篇
儿科学   36篇
妇产科学   2篇
基础医学   42篇
口腔科学   18篇
临床医学   34篇
内科学   133篇
皮肤病学   8篇
神经病学   10篇
特种医学   79篇
外科学   64篇
综合类   62篇
预防医学   20篇
眼科学   8篇
药学   20篇
肿瘤学   20篇
  2024年   1篇
  2023年   2篇
  2022年   5篇
  2021年   6篇
  2020年   5篇
  2019年   2篇
  2018年   6篇
  2017年   4篇
  2016年   9篇
  2015年   16篇
  2014年   11篇
  2013年   17篇
  2012年   11篇
  2011年   9篇
  2010年   19篇
  2009年   32篇
  2008年   11篇
  2007年   20篇
  2006年   31篇
  2005年   8篇
  2004年   9篇
  2003年   3篇
  2002年   7篇
  2001年   10篇
  2000年   7篇
  1999年   13篇
  1998年   42篇
  1997年   31篇
  1996年   40篇
  1995年   17篇
  1994年   18篇
  1993年   22篇
  1992年   4篇
  1991年   8篇
  1990年   2篇
  1989年   9篇
  1988年   24篇
  1987年   9篇
  1986年   9篇
  1985年   17篇
  1984年   7篇
  1983年   4篇
  1982年   3篇
  1981年   3篇
  1980年   3篇
  1977年   3篇
  1976年   5篇
  1975年   3篇
排序方式: 共有557条查询结果,搜索用时 15 毫秒
61.
Fifteen allograft transplant recipients acquired lymphoproliferative disorders after immunosuppressive therapy with cyclosporine and steroids. Many of these lymphoproliferative disorders regressed or disappeared completely after reduction of cyclosporine dose. This disease has several aspects that distinguish it from usual posttransplantation lymphomas that occur with regimens that do not contain cyclosporine. The time course from transplantation to onset of lymphoma is relatively short, with an average of approximately 8 months. Organs show a wide spectrum of abnormalities typical of other immunosuppression-associated lymphomas, but there is unique sparing of the central nervous system. The tumor is also unique in that it responds to a decrease in the cyclosporine dose.  相似文献   
62.
63.
我非常高兴向大家推荐这份发展中国家幽门螺杆菌(H.priori)临床指南。该指南的编译是由数位在该领域具有丰富临床经验的世界知名专家共同完成的。  相似文献   
64.
65.

OBJECTIVE:

To determine the prevalence of vancomycin-resistant enterococci (VRE) bowel colonization in hospitalized patients in Manitoba who had stool specimens collected for Clostridium difficile toxin and/or culture testing.

DESIGN:

Two tertiary care and five community hospitals in Winnipeg and three rural Manitoba community hospitals participated in this study. From January 1 to December 31, 1997 stool specimens, one per patient, submitted to hospital microbiology laboratories for C difficile toxin and/or culture testing were screened for VRE on colistin-nalidixic acid-vancomycin (6 μg/mL) (CNAV) agar plates. The study was divided into six, eight-week intervals. Stool specimens received in the first two weeks of each eight week interval were screened for VRE.

MAIN RESULTS:

A total of 1408 stool specimens were submitted over the 48-week study period. Sixty-seven (4.8%) patients with VRE colonization of their lower gastrointestinal tract were identified. Three of the 67 (4.5%) VRE isolates were Enterococcus faecium, with the remaining 64 (95.5%) were Enterococcus gallinarum. The three vancomycin-resistant E faecium -VREF- (from two different Winnipeg hospitals) demonstrated the vanA genotype, and were resistant to vancomycin, teicoplanin and ampicillin. All three VREF isolates also demonstrated high level resistance to both gentamicin and streptomycin but were susceptible to quinuprisitin/dalfopristin and LY333328.

CONCLUSION:

VRE colonization in hospitalized patients in Manitoba is infrequent and most commonly due to E gallinarum. The prevalence of VREF colonization in the patients studied was 0.2% (three of 1408).Key Words: Manitoba, Prevalence, Vancomycin-resistant enterococciVancomycin-resistant Enterococcus faecium (VREF) accounts for up to 65% of E faecium isolates in hospitalized patients across the United States and is endemic in many North American tertiary care institutions (1,2). The management of these infections presents a significant clinical challenge because species of the genus Enterococcus, and in particular E faecium, are frequently resistant to several antimicrobial agents (3). High level penicillin resistance, high level aminoglycoside resistance and most recently vancomycin resistance are emerging as significant concerns in the treatment of enterococcal infections. This has prompted the development and evaluation of new antimicrobial agents such as quinupristin/dalfopristin and LY333328, a glycopeptide, which may offer activity against enterococci resistant to conventional therapy (2).VREF is not endemic in Manitoba hospitals, and infection with VREF is extremely rare (4). However, the prevalence of VREF lower gastrointestinal tract (GIT) carriage, which frequently precedes infection (5,6), is presently unknown for patients hospitalized in Manitoba. To determine whether the lack of VREF endemnicity correlated with an absence of lower GIT colonization, we assessed lower GIT carriage of VREF for patients hospitalized in 10 Manitoba hospitals from January 1 to December 31, 1997. Our study was consistent with Centers for Disease Control and Prevention guidelines (Atlanta, Georgia) that suggest surveillance programs for vancomycin-resistant enterococci (VRE) be undertaken on an intermittent basis in areas where VRE is not known to be endemic (6). Isolates of VREF identified were phenotypically and genotypically characterized, and tested for their susceptibilities against a panel of antimicrobial agents.  相似文献   
66.
67.
From 1990 to 1993 we performed a prospective study of busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg) in 30 patients with refractory anemia (RA) undergoing related (n = 17) or unrelated (n = 13) donor marrow transplantation. Nineteen patients survive disease free (63% 3- year actuarial disease-free survival [DFS]) and no patient relapsed. These results were compared to those of 38 historical controls with RA treated with cyclophosphamide and total body irradiation, of whom 22 are disease-free survivors and 1 relapsed. After correcting for significant variables between the two treatment groups, we found no statistically significant difference in outcome based on preparative regimen. Combining data from these 68 patients plus 2 additional patients with RA treated before 1993 with busulfan and cyclophosphamide, we identified four variables independently associated with improved survival: younger age, shorter disease duration, lower neutrophil count pretransplant, and lower hematocrit pretransplant. We also found that 15 patients 40 to 55 years of age had a 46% 3-year actuarial DFS and 26 patients receiving unrelated or mismatched related donor marrow had a 50% 3-year actuarial DFS. We conclude that there does not appear to be any significant difference in outcome based on preparative regimen in this patient population. In addition, allogeneic bone marrow transplantation may be a reasonable approach to therapy of RA early after diagnosis. However, whether early intervention with transplantation prolongs survival over that expected without transplantation cannot be ascertained with certainty from available data.  相似文献   
68.
Abstract Background: Cardiac surgical patients with postoperative complications frequently require prolonged intensive care yet survive to hospital discharge. Methods: From January 1, 2002 to December 31, 2007, 11,541 consecutive patients underwent cardiac operations at a single academic institution. Of these, 11,084 (95.9%) survived to hospital discharge and comprised the study sample. Patients were retrospectively categorized into four groups according to intensive care unit (ICU) length of stay (LOS): <3 days, three to seven days, 7 to 14 days, and >14 days. Survival at 12 months was determined using the Social Security Death Index. Kaplan–Meier (KM) survival curves and Cox proportional hazards regression modeling (hazard ratio, HR) were used to analyze group differences in survival. Results: One‐year survival among the four groups according to ICU LOS was: <3 days, 97.0% (8407/8666); three to seven days, 91.2% (1481/1625); 7 to 14 days, 87.9% (356/405); and >14 days, 68.3% (265/388) (p < 0.001). Using multivariable regression analysis, adjusted overall mortality was significantly greater in patients with ICU LOS of three to seven days (HR = 1.51), 7 to 14 days (HR = 1.40), and >14 days (HR = 1.90) compared to patients with ICU LOS <3 days. Mortality among patients who survived more than six months postsurgery was significantly greater in patients with ICU LOS of three to seven days (HR = 1.37), 7 to 14 days (HR = 1.34), and >14 days (HR = 1.63). Conclusions: Although cardiac surgery patients with major postoperative complications frequently survive to hospital discharge, survival after discharge is significantly reduced in patients requiring prolonged ICU care. Reduced survival in patients with a high risk of complications and anticipated long ICU stays should be considered when discussing surgical versus nonsurgical options. (J Card Surg 2012;27:13‐19)  相似文献   
69.
70.
Holocarboxylase synthetase (HCS) catalyses the biotinylation of the four biotin-dependent carboxylases found in humans. A deficiency in HCS results in biotin-responsive multiple carboxylase deficiency (MCD). We have identified six different point mutations in the HCS gene in nine patients with MCD. Two of the mutations are frequent among the MCD patients analyzed. Four of the mutations cluster in the putative biotin- binding domain as deduced from the corresponding Escherichia coli enzyme and consistent with an explanation for biotin-responsiveness based on altered affinity for biotin. The two others may define an additional domain involved in biotin-binding or biotin-mediated stabilization of the protein.   相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号