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   3263篇
  免费   181篇
  国内免费   12篇
耳鼻咽喉   19篇
儿科学   67篇
妇产科学   83篇
基础医学   492篇
口腔科学   59篇
临床医学   241篇
内科学   922篇
皮肤病学   88篇
神经病学   280篇
特种医学   44篇
外科学   314篇
综合类   17篇
预防医学   287篇
眼科学   38篇
药学   220篇
中国医学   14篇
肿瘤学   271篇
  2023年   30篇
  2022年   57篇
  2021年   112篇
  2020年   68篇
  2019年   91篇
  2018年   98篇
  2017年   75篇
  2016年   81篇
  2015年   99篇
  2014年   124篇
  2013年   170篇
  2012年   221篇
  2011年   273篇
  2010年   129篇
  2009年   137篇
  2008年   237篇
  2007年   230篇
  2006年   215篇
  2005年   211篇
  2004年   181篇
  2003年   168篇
  2002年   155篇
  2001年   23篇
  2000年   14篇
  1999年   17篇
  1998年   22篇
  1997年   16篇
  1996年   23篇
  1995年   15篇
  1994年   17篇
  1993年   6篇
  1992年   15篇
  1991年   8篇
  1990年   9篇
  1989年   11篇
  1988年   4篇
  1987年   7篇
  1982年   5篇
  1980年   3篇
  1978年   4篇
  1977年   3篇
  1976年   6篇
  1975年   6篇
  1974年   4篇
  1973年   3篇
  1972年   7篇
  1971年   3篇
  1970年   4篇
  1941年   3篇
  1940年   3篇
排序方式: 共有3456条查询结果,搜索用时 15 毫秒
51.
Background.?Ribavirin (RBV) exposure seems to be critical to maximize treatment response in human immunodeficiency virus (HIV)-positive patients with chronic hepatitis C virus (HCV) infection. Methods.?HIV/HCV-coinfected individuals naive to interferon were prospectively randomized to receive peginterferon-α-2a (180?μg/d) plus either RBV standard dosing (1000 or 1200?mg/d if <75 or ≥75?kg, respectively) or RBV induction (2000?mg/d) along with subcutaneous erythropoietin β (450?IU/kg/wk), both during the first 4 weeks, followed by standard RBV dosing until completion of therapy. Early stopping rules at weeks 12 and 24 were applied in patients with suboptimal virological response. Results.?A total of 357 patients received ≥1 dose of the study medication. No differences in main baseline characteristics were found when comparing treatment arms. Sustained virological response (SVR) was attained by 160 (45%) patients, with no significant differences between RBV induction and standard treatment arms (SVR in 72 of 169 patients [43%] vs 88 of 188 [47%], respectively). At week 4, undetectable HCV RNA (29% vs 25%) and mean RBV trough concentration (2.48 vs 2.14?μg/mL) were comparable in both arms, whereas mean hemoglobin decay was less pronounced in the RBV induction plus erythropoietin arm than in the RBV standard dosing arm (-1.7 vs -2.3?mg/dL; P?相似文献   
52.
53.
In a study conducted on 114 patients undergoing unrelated donor haematopoietic stem cell transplantation (HSCT) for thalassaemia, we observed that the lack of activating killer immunoglobulin-like receptors (KIRs) on donor natural killer (NK) cells significantly increased the risk of graft-versus-host disease (GvHD) [hazard risk (HR) 4.2, 95% confidence interval (CI) 1.7-10.1, P = 0.002] and transplantation-related mortality (HR 4.7, 95% CI 1.6-14.2, P = 0.01). The risk of GvHD furthermore increased when recipients heterozygous for HLA-C KIR ligand groups (C1/C2) were transplanted from donors completely lacking activating KIRs (HR 6.1, 95% CI 1.9-19.2, P = 0.002). We also found that the risk of rejection was highest when the recipient was homozygous for the C2 HLA-KIR ligand group and the donor carried two or more activating KIRs (HR 6.8, 95% CI 1.9-24.4, P = 0.005). By interpolating the number of donor activating KIRs with recipient HLA-C KIR ligands, we created an algorithm capable of stratifying patients according to the immunogenetic risk of complications following unrelated HSCT. In clinical practice, this predictive tool could serve as an important supplement to clinical judgement and decision-making.  相似文献   
54.
55.
56.
Smoldering myeloma is an asymptomatic plasma cell dyscrasia with a heterogeneous propensity to progress to active myeloma. In order to investigate the biology of smoldering myeloma patients with high risk of progression, we analyzed the genomic characteristics by FISH, SNP-arrays and gene expression profile of a group of patients with high-risk smoldering myeloma included in a multicenter randomized trial. Chromosomal abnormalities detected by FISH and SNP-arrays at diagnosis were not associated to risk of progression to symptomatic myeloma. However, the overexpression of four SNORD genes (SNORD25, SNORD27, SNORD30 and SNORD31) was correlated with shorter time to progression (P<0.03). When plasma cells from high-risk smoldering patients who progressed to symptomatic myeloma were sequentially analyzed, newly acquired lesions together with an increase in the proportion of plasma cells carrying a given abnormality were observed. These findings suggest that gene expression profiling is a valuable technique to identify smoldering myeloma patients with high risk of progression. (Clinical Trials NCT00443235).  相似文献   
57.
58.
Extramedullary (e) relapse in multiple myeloma(MM) has an adverse prognosis, but knowledge concerning biological features and preferred treatment is scarce. We screened the myeloma registry of our institution for eMM relapses and identified 24 cases among 357 patients (pts).Only 8% of eMM relapses occurred after initial therapy, but 54% occurred after third-line or subsequent therapy. Baseline molecular cytogenetics revealed high-risk features in 10 of 19 evaluable patients. Most frequently, eMM presented as soft tissue (67%) and organ involvement (25%) or malignant effusion (12.5%). Incidence of leptomeningeal/CNS involvement was 21%. At eMM relapse, bone marrow infiltration was absent in 46% and low in 21%. Ten eMM biopsies were available showing increased proliferation, i.e., Ki-67 of 67%(range, 30–90%) of all cancer cells. Pts received radiation therapy, dose-intense chemotherapy, novel agents, and allogeneic SCT resulting in an overall response rate of 54%. Median progression-free survival was 2 (95% CI 0.08–3.92) and median overall survival 7 months (95% CI 3.56–10.43), respectively,with only three patients being alive at 12 months from diagnosis. EMM relapse may present at any anatomical site with frequent CNS involvement. Biological features include increased proliferation and low rate of marrow involvement.Prognosis remains poor despite intensive treatment.  相似文献   
59.
60.
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