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   790篇
  免费   59篇
  国内免费   5篇
耳鼻咽喉   4篇
儿科学   10篇
妇产科学   3篇
基础医学   104篇
口腔科学   2篇
临床医学   44篇
内科学   329篇
皮肤病学   7篇
神经病学   25篇
特种医学   16篇
外科学   127篇
综合类   16篇
预防医学   64篇
眼科学   21篇
药学   60篇
肿瘤学   22篇
  2019年   6篇
  2018年   7篇
  2017年   3篇
  2016年   8篇
  2015年   9篇
  2014年   15篇
  2013年   33篇
  2012年   54篇
  2011年   51篇
  2010年   22篇
  2009年   30篇
  2008年   51篇
  2007年   63篇
  2006年   63篇
  2005年   44篇
  2004年   38篇
  2003年   41篇
  2002年   26篇
  2001年   22篇
  2000年   27篇
  1999年   35篇
  1998年   16篇
  1997年   3篇
  1996年   5篇
  1995年   11篇
  1994年   9篇
  1993年   11篇
  1992年   22篇
  1991年   18篇
  1990年   21篇
  1989年   17篇
  1988年   7篇
  1987年   7篇
  1986年   4篇
  1985年   7篇
  1984年   5篇
  1983年   3篇
  1982年   6篇
  1981年   4篇
  1978年   4篇
  1974年   3篇
  1973年   2篇
  1972年   2篇
  1969年   3篇
  1947年   1篇
  1946年   2篇
  1944年   1篇
  1939年   1篇
  1936年   1篇
  1870年   1篇
排序方式: 共有854条查询结果,搜索用时 31 毫秒
1.
2.
背景与目的:原发性胆汁性肝硬化(PBC)伴系统性硬化症(SSc)的预后仍不十分清楚,该研究拟对其临床特点及预后进行评估。方法:从一个含580例患者的PBC数据库中选出43例PBC伴SSc患者,同时为每例PBC—SSc患者匹配2例单纯PBC患者作为对照,监测初次就医时的血清胆红素浓度。结果:局限皮肤型SSc者40例(93%)。诊断PBC时的中位年龄为49.7岁,胆红素浓度为17μmol/L,白蛋白水平为40.5g/L。24例(56%)患者于SSc后在中值为4.9年发生PBC。配对患者诊断PBC时的中位年龄为53.2岁、胆红素浓度为12μmol/L、白蛋白水平为41g/L。两组患者中位随访时间相似:PBC—SSc组为3.16年,单纯PBC组为4.8年。PBC—SSc患者南于较少接受移植手术(HR0.068;P:0.006),在校正性别、年龄、胆红素对数及碱性磷酸酶等因素后,其移植术或死亡风险(HR0.116;P=0.01)均明显降低,同时胆红素上升的比例亦较低(P=0.04)。  相似文献   
3.
To assess the sites, incidence, and bacteriology of infections in intensive care burn patients, a prospective survey of all admissions to a tertiary care institution burn unit was carried out over a 12-month period. One hundred and sixteen patients were admitted, 106 with a diagnosis of thermal burns. Forty patients developed 90 infections. Only two deaths occurred, one in a patient with sepsis. In order of frequency, pneumonia, burn infection, UTI and primary bacteraemia were most common. Staphylococcal species accounted for a majority of infections at all body sites except UTI (47 per cent of all infections, including 11 of 14 bacteraemic infections). Staph. aureus sepsis was more common in those carrying the organism on admission. Strain typing of paired admission and subsequent clinical isolates in 19 patients with Staph. aureus sepsis indicated that eight (42 per cent) became infected with a strain they carried on admission. Further reductions in septic complications of burns in our center would be best directed at staphylococcal species, particularly Staph. aureus. Both eradication of carrier state, and prevention of acquisition of Staph. aureus strains could be explored.  相似文献   
4.
We present a patient with a facial movement disorder that has characteristics of both blepharospasm and bilateral asynchronous hemifacial spasm. Because of the increased incidence of blepharospasm in patients with hemifacial spasm, our patient's clinical presentation is probably not a chance occurrence, but rather a manifestation of some predisposition for these two movement disorders. This unusual constellation of signs and symptoms challenges the current diagnostic criteria and suggests that some of these facial movement disorders may lie on a spectrum, rather than represent distinct entities.  相似文献   
5.
Endoscopic sphincterotomy (ES) is the treatment of choice for common bile duct stones in elderly patients. For those in whom endoscopic clearance of the common bile duct fails the treatment options include stenting, dissolution therapy and lithotripsy. Surgery is often avoided because of the reported high morbidity and mortality in elderly patients. We have reviewed the outcome of patients referred for surgery after failed endoscopic clearance of common bile duct stones. Over a 3-year period, 100 patients with common bile duct stones were referred specifically for endoscopic clearance of the common bile duct (median age 69 years, range 19-97 years). In seven patients duct clearance was possible without ES and in five patients ES was considered inappropriate. ES was attempted in 88 patients and was successful in 75 (85%). Of the 13 patients failing ES or stone removal, surgery was performed in nine and four were stented. Of patients having successful ES (n = 75), ten were referred for surgery because of incomplete duct clearance. Surgery was performed to obtain duct clearance in 19 patients (eight male, 11 female, median age 77 years, range 47-90 years). Of the 19, eight had previously undergone a cholecystectomy (42%) and 17 of the 19 had biliary tract drainage preoperatively (90%). The procedures performed consisted of choledocholithotomy in all plus cholecystectomy (11), choledochoduodenostomy (7) and choledochojejunostomy (7). There were no deaths and only one major complication. The median total inpatient stay was 26 days (range 14-75 days) and the median postoperative stay was 12 days (range 7-50 days). We would conclude that open surgery can be performed safely and effectively in elderly patients with retained bile duct stones.  相似文献   
6.
7.
Ovine T-cell lines (including one clone [101A]), which are specific for Bluetongue virus serotype 1 (BTV1), have been established and characterized. Although these T-cell lines react with different isolates of BTV1 (including those from South Africa, Australia, Nigeria, and Cameroon), they do not react with heterologous BTV serotypes. Antigen specificity of these T-cells was studied using purified virus particles, infectious subviral particles (ISVP) and cores, or using individual BTV structural proteins that were either isolated by SDS-PAGE or expressed by recombinant strains of vaccinia virus. The results showed that each of the T-cell lines reacted with outer capsid protein VP2 (the BTV protein exhibiting most serotype-specific variation and the major neutralization antigen). However, all of the uncloned T-cell lines also reacted with either the core structural proteins or the outer capsid protein VP5. In contrast, the T-cell clone 101A only reacted with outer capsid protein VP2. Cell surface marker analysis showed that 101A has a helper T-cell phenotype (CD5+, CD4+, CD8-, T-19-). The T-cell lines and clone 101A all produced large amounts of interleukin 2 (IL-2) when stimulated with purified BTV1 virus particles, or with VP2 (up to 120 IU/ml from 2 x 10(5) T-cells). BTV serotype-specific antigenic sites, for B cells and at least one site for ovine helper T-cells, are therefore located within VP2.  相似文献   
8.
9.
Patients with primary biliary cirrhosis have an abnormally high incidence of urinary tract infection (35%). Susceptibility to urinary infection and other infectious diseases has been linked with certain blood group antigens and secretor status. We have therefore studied these characteristics in patients with primary biliary cirrhosis. We were unable to show any abnormal distribution in blood groups or secretor status in patients with primary biliary cirrhosis (compared with a normal population) which might reflect their predisposition to urinary infection. The distribution of blood groups and secretor status in patients with primary biliary cirrhosis with a history of urinary infections was not significantly different from patients without such a history. Escherichia coli strains isolated from patients with primary biliary cirrhosis did not bind in any greater numbers to the uroepithelial cells of primary biliary cirrhosis patients than to the cells of a normal healthy control. We therefore conclude that blood group distribution, abnormal secretor status, and epithelial cell type are not important factors in the predisposition of primary biliary cirrhosis patients to urinary infections.  相似文献   
10.
BACKGROUND: Depression is the most common mental health disorder in people aged over 65 years. Late-life depression is associated with chronic illness and disability. AIM: To investigate the feasibility of a collaborative care model for depression in older people in a primary care setting. DESIGN OF STUDY: Randomised controlled trial with 16-weeks follow up. SETTING: A primary care trust in Manchester. METHOD: Participants were 105 people aged 60 years or older who scored 5 or more on the Geriatric Depression Scale; 53 were randomly allocated to an intervention group and 52 to a usual care group. The intervention group received care managed by a community psychiatric nurse who delivered an intervention comprising a facilitated self-help programme with close liaison with primary care professionals and old-age psychiatry according to a defined protocol. The usual care group received usual GP care. A nested qualitative study explored the views of the health professionals and patients regarding the acceptability and effectiveness of the intervention. RESULTS: The main outcome measure was recovery from depression. Patients in the intervention group were less likely to suffer from major depressive disorder at follow up compared with usual care (0.32, 95% confidence = interval = 0.11 to 0.93, P = 0.036). The qualitative component of the study demonstrated the acceptability of the intervention to patients. CONCLUSION: A model of collaborative care for older people with depression, used in a primary care setting with a facilitated self-help intervention is more effective than usual GP care. This study demonstrates that the implementation of a collaborative care model is feasible in UK primary care and that the intervention is effective and acceptable to patients.  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