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   707篇
  免费   43篇
  国内免费   5篇
耳鼻咽喉   6篇
儿科学   32篇
妇产科学   14篇
基础医学   90篇
口腔科学   23篇
临床医学   57篇
内科学   181篇
皮肤病学   29篇
神经病学   27篇
特种医学   11篇
外科学   137篇
综合类   5篇
预防医学   62篇
眼科学   9篇
药学   41篇
中国医学   5篇
肿瘤学   26篇
  2023年   7篇
  2022年   19篇
  2021年   28篇
  2020年   16篇
  2019年   24篇
  2018年   23篇
  2017年   12篇
  2016年   15篇
  2015年   21篇
  2014年   30篇
  2013年   33篇
  2012年   43篇
  2011年   49篇
  2010年   33篇
  2009年   29篇
  2008年   50篇
  2007年   53篇
  2006年   45篇
  2005年   39篇
  2004年   49篇
  2003年   26篇
  2002年   36篇
  2001年   4篇
  2000年   4篇
  1999年   8篇
  1998年   6篇
  1997年   5篇
  1995年   2篇
  1993年   2篇
  1991年   2篇
  1988年   1篇
  1987年   1篇
  1986年   2篇
  1985年   1篇
  1984年   3篇
  1983年   2篇
  1982年   1篇
  1979年   3篇
  1976年   3篇
  1975年   5篇
  1974年   1篇
  1973年   3篇
  1972年   3篇
  1971年   2篇
  1970年   1篇
  1969年   1篇
  1968年   2篇
  1967年   1篇
  1962年   1篇
  1923年   1篇
排序方式: 共有755条查询结果,搜索用时 15 毫秒
31.
Gómez O 《Lancet》2003,361(9367):1477; author reply 1477
  相似文献   
32.
Laparoscopic management of symptomatic and large adrenal cysts   总被引:6,自引:0,他引:6  
PURPOSE: We present the feasibility and results of the laparoscopic management of symptomatic and large adrenal cysts. MATERIALS AND METHODS: From June 1993 to April 2004 we performed 149 laparoscopic adrenalectomies. In this series 8 patients with symptomatic adrenal cysts or pseudocysts were treated laparoscopically. Surgical indications for laparoscopic management of adrenal cysts were abdominal pain in 5 cases and cyst size 5 cm or greater in 3. RESULTS: The incidence of adrenal cyst was 5.4% (8 of 149 cases). Six patients underwent laparoscopic adrenal cyst decortication and marsupialization, 1 underwent laparoscopic partial adrenalectomy and 1 underwent laparoscopic adrenalectomy. Mean operative time was 77.5 minutes. There were no intraoperative or postoperative complications. Mean hospital stay was 1.7 days. At a mean followup of 18.5 months all patients were asymptomatic and without radiographic evidence of cyst recurrence. CONCLUSIONS: Laparoscopic conservative management of adrenal cysts is safe and feasible. Laparoscopic decortication and marsupialization should be the preferred treatment option for symptomatic adrenal cysts. Laparoscopic partial adrenalectomy or a total adrenalectomy can be performed in cases of larger cysts which compromise most of the adrenal gland. To our knowledge, this represents the largest series of symptomatic adrenal cysts managed laparoscopically.  相似文献   
33.
34.
BACKGROUND: The pathogenesis of HIV encephalopathy is poorly understood especially in children. Studies suggest that HIV replication and the release of proinflammatory mediators in the central nervous system contribute to the pathogenesis of HIV dementia in adults. METHODS: Cerebrospinal fluid (CSF) and plasma samples from 23 HIV-infected children were longitudinally analyzed at Weeks 0, 8, 16 and 48 for HIV RNA and concentrations of the following proinflammatory mediators: monocyte chemotactic protein-1 (MCP-1), tumor necrosis factor-alpha, regulated upon activation, normal T cell expressed and secreted (RANTES), macrophage-inflammatory protein (MIP)-1-alpha, MIP-1-beta and matrix metalloproteinase-9 (MMP-9). RESULTS: All 23 children had detectable concentrations of MCP-1 in the CSF at all time points evaluated. However, of the remaining of proinflammatory mediators measured in CSF at baseline, only a few children had detectable concentrations: tumor necrosis factor-alpha, n = 1; RANTES, n = 5; MMP-9, n = 9; MIP-1-alpha and MIP-1-beta, n = 0. A reduction from baseline to Week 48 was observed in CSF concentrations of MCP-1 and, among children with detectable values, MMP-9, which paralleled declines in CSF HIV RNA. CONCLUSION: These results suggest that MCP-1 and MMP-9 may be involved in the pathogenesis of central nervous system disease in HIV-infected children.  相似文献   
35.
Cesarean sections rates have increased considerably in high- and middle-income countries in recent years. In Latin America the rates of surgical births reached 30% in Brazil, 40% in Chile, and 36% in Mexico. This essay describes the relationship of cesarean section with several mythological characters, presents a brief history of surgical births, and discusses the possible origin of its explosive increase. Among the factors associated to this epidemic we can mention economic incentives, a mounting supply of specialists, and the lack of comprehensive information on birth alternatives for pregnant women. The essay concludes with a call for a generalized control of this procedure based on evidence gathered through different kinds of interventions.  相似文献   
36.
This study investigated whether the anatomical differences between right and left internal jugular vein catheterization (RJVC and LJVC) would lead to differences in the frequency of complications, in particular, central vein occlusion (CVO). A group of 479 jugular vein catheterizations, 403 RJVC and 77 LJVC done in 294 prevalent hemodialysis patients were analyzed. A right-sided carotid pseudoaneurysm was the only major puncture-related complication. A total of 78 RJVC and 17 LJVC were inserted more than once in the same position. Of the RJVC, 44 (10.9%) of 403 were removed because of infection compared with 16 (20.8%) of 77 LJVC (P < 0.02). The overall incidence of infections was 1.58 episodes of infection per 1000 catheter days, 1.57 for RJVC and 3.72 for LJVC, respectively. Catheter dwell times were not different. A group of 127 patients with former RJVC and 44 with LJVC had ipsilateral arteriovenous access (RJVC+ and LJVC+ group, respectively). Four diabetic LJVC+ developed severe arm swelling secondary to CVO leading ultimately to access ligation. The RJVC+ group had no access ligated. LJVC may cause CVO in diabetics.  相似文献   
37.
38.
BACKGROUND: Although epileptic crises are equally frequent in women and men, several factors cause female epileptics to present a series of gender-specific problems. To date, few studies have been published on the kinetics of carbamazepine (CBZ) and carbamazepine 10,11-epoxide (CBZ-E) active metabolite in a Mexican population, and no information for epileptic women of reproductive age is available. The aim of the present work was to study the pharmacokinetic behavior of this group of women during steady state. METHODS: Fourteen epileptic women under chronic treatment receiving only the anticonvulsant CBZ to control their crises were studied. A blood sample was taken before breakfast, before the morning dose of 200 mg, and after the dose at 1, 2, 3, 4, 5, and 8 h. Serum was separated by centrifugation at 1,350 x g. Serum concentrations of carbamazepine (CBZ) and of the metabolite carbamazepine 10,11-epoxide (CBZ-E) were measured by HPLC. Pharmacokinetic parameters were calculated by statistical moment method after obtaining serum concentrations. RESULTS: Maximum time (T(max)) for CBZ was reached at 2.72+/-0.71 h and for CBZ-E, it was 3.60+/-0.79 h. C(max) for CBZ was 7.30+/-2.30 microg/mL, while C(min) for CBZ was 6.30+/-2.49. Maximum serum values for CBZ-E were 1.01+/-0.57, equivalent to 13.80% of CBZ; t(12) value for CBZ and CBZ-E was 18.20 and 16.10 h, respectively. AUC values for CBZ and metabolite were 70.33+/-17.10 microg/L/h and 9.20+/-2.50 microg/L/h, respectively. CBZ and CBZ-E clearance did not show differences and were 0.37 mL/kg/min and 0.40 mL/kg/min, respectively. Extraction index for serum concentrations of CBZ and CBZ-E AUC(CBZ)/AUC(CBZ-E) was 0.13; positive correlation was observed between serum concentrations of CBZ and E-CBZ, with r=0.94. CONCLUSIONS: The schedule we suggest for therapeutic monitoring of serum concentrations of CBZ in chronic treatments is 3 h for maximum peak concentration of C(max) after dose administration and for minimum peak concentration, C(min) prior to subsequent administration of the dose.  相似文献   
39.
The polymerase chain reaction amplification of a fragment of the B1 gene of Toxoplasma gondii coupled to hybridization was performed in 42 patients from Rio de Janeiro, Brazil. The results showed 50% of positivity in the IgM positive toxoplasmosis group, and 12.5% in the positive IgG and negative IgM individuals. The data presented here revealed a lack of specificity of the molecular approach, clearly indicating that the primers used may co-amplify human sequences.  相似文献   
40.
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