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   4375篇
  免费   225篇
  国内免费   36篇
耳鼻咽喉   46篇
儿科学   53篇
妇产科学   59篇
基础医学   528篇
口腔科学   122篇
临床医学   309篇
内科学   1425篇
皮肤病学   88篇
神经病学   358篇
特种医学   100篇
外科学   611篇
综合类   23篇
一般理论   1篇
预防医学   195篇
眼科学   68篇
药学   274篇
中国医学   8篇
肿瘤学   368篇
  2023年   29篇
  2022年   42篇
  2021年   96篇
  2020年   63篇
  2019年   78篇
  2018年   111篇
  2017年   74篇
  2016年   84篇
  2015年   109篇
  2014年   163篇
  2013年   189篇
  2012年   289篇
  2011年   297篇
  2010年   175篇
  2009年   161篇
  2008年   296篇
  2007年   328篇
  2006年   287篇
  2005年   329篇
  2004年   302篇
  2003年   267篇
  2002年   218篇
  2001年   43篇
  2000年   32篇
  1999年   34篇
  1998年   29篇
  1997年   22篇
  1996年   28篇
  1995年   45篇
  1994年   32篇
  1993年   25篇
  1992年   31篇
  1991年   21篇
  1990年   21篇
  1989年   12篇
  1988年   16篇
  1987年   23篇
  1986年   13篇
  1985年   12篇
  1984年   24篇
  1983年   20篇
  1982年   18篇
  1981年   10篇
  1980年   8篇
  1979年   8篇
  1977年   11篇
  1976年   7篇
  1975年   10篇
  1974年   6篇
  1971年   7篇
排序方式: 共有4636条查询结果,搜索用时 296 毫秒
1.
Colorectal cancer (CRC) screening programs help diagnose cancer precursors and early cancers and help reduce CRC mortality. However, currently recommended tests, the fecal immunochemical test (FIT) and colonoscopy, have low uptake. There is therefore a pressing need for screening strategies that are minimally invasive and consequently more acceptable to patients, most likely blood based, to increase early CRC identification. MicroRNAs (miRNAs) released from cancer cells are detectable in plasma in a remarkably stable form, making them ideal cancer biomarkers. Using plasma samples from FIT-positive (FIT+) subjects in an Italian CRC screening program, we aimed to identify plasma circulating miRNAs that detect early CRC. miRNAs were initially investigated by quantitative real-time PCR in plasma from 60 FIT+ subjects undergoing colonoscopy at Fondazione IRCCS Istituto Nazionale dei Tumori, then tested on an internal validation cohort (IVC, 201 cases) and finally in a large multicenter prospective series (external validation cohort [EVC], 1121 cases). For each endoscopic lesion (low-grade adenoma [LgA], high-grade adenoma [HgA], cancer lesion [CL]), specific signatures were identified in the IVC and confirmed on the EVC. A two-miRNA-based signature for CL and six-miRNA signatures for LgA and HgA were selected. In a multivariate analysis including sex and age at blood collection, the areas under the receiver operating characteristic curve (95% confidence interval) of the signatures were 0.644 (0.607–0.682), 0.670 (0.626–0.714) and 0.682 (0.580–0.785) for LgA, HgA and CL, respectively. A miRNA-based test could be introduced into the FIT+ workflow of CRC screening programs so as to schedule colonoscopies only for subjects likely to benefit most.  相似文献   
2.
3.
4.
5.
6.
7.
8.
Mechanical intravascular hemolysis is frequently observed following procedures on heart valves and uncommonly observed in native valvular disease. In most cases, its severity is mild. Nevertheless, it can be clinically significant and even life threatening, requiring multiple blood transfusions and renal replacement therapy. This paper reviews the current knowledge on mechanical intravascular hemolysis in valvular disease, before and after correction, focusing on pathophysiology, approach to diagnosis, and impact of other hematological conditions on the resultant anemia. The importance of a multidisciplinary management is underscored. Laboratory data are provided about subclinical hemolysis that is commonly observed following the implantation of surgical and transcatheter valve prostheses and devices. Finally, clinical scenarios are reviewed and current medical and surgical treatments are discussed, including alternative options for inoperable patients.  相似文献   
9.
International Journal of Clinical Oncology - Immune-checkpoint inhibitors (ICIs) are standard treatments for metastatic non-small cell lung cancer (NSCLC). Patients with poor performance status...  相似文献   
10.
BackgroundOutcomes of newly diagnosed multiple myeloma (NDMM) in developing regions have not paralleled those in developed settings. Economic disadvantage, comorbidities, and aggressive disease behavior play competing roles on defining outcomes. Our aim was to analyze the impact of socioeconomic characteristics and comorbidities on therapy initiation, drug selection, and survival outcomes of NDMM in a resource-constrained setting.Patients and MethodsThis retrospective single-center cohort included ≥ 18-year-old NDMM patients from January 2006 to December 2018.ResultsA total of 245 patients were included with a median age of 62 years, Eastern Cooperative Oncology Group performance status ≤ 2 in 70.2%, International Staging System score ≥ 2 in 89.4%, and high-risk disease in 31.6%. Comorbidities were reported in 69.4%, and Charlson comorbidity index (CCI) was ≥ 2 in 64.1%. A total of 87.4% (n = 214) received thalidomide-, alkylating-, and bortezomib-based induction in 67.8%, 18.2%, and 13.1%. Patient-related factors including performance status, comorbidities, and CCI, but not myeloma-related factors, were associated with a decreased likelihood of initiating induction therapy. On multivariate analysis, CCI ≥ 2 remained statistically significant (odds ratio, 5.81; P = .005). Overall survival was 44 months. Although both patient- and myeloma-related factors were associated with a decreased overall survival, only International Staging System score > 2 (hazard ratio, 3.53; P = .004) and induction without bortezomib-based regimens (hazard ratio, 4.45; P < .001) were statistically significant on multivariate analysis.ConclusionMyeloma- and treatment-related factors are the main determinants of survival in NDMM induction-eligible patients. Patient-related factors play a pivotal role determining access to therapy and survival outcomes. Comorbidity index and performance status were determinant on defining therapy initiation in this real-world population, which emphasizes the need to improve health baseline conditions in resource-constrained settings.  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