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   9714篇
  免费   723篇
  国内免费   80篇
耳鼻咽喉   68篇
儿科学   239篇
妇产科学   72篇
基础医学   1084篇
口腔科学   199篇
临床医学   669篇
内科学   2773篇
皮肤病学   392篇
神经病学   697篇
特种医学   501篇
外科学   1642篇
综合类   46篇
一般理论   1篇
预防医学   232篇
眼科学   161篇
药学   541篇
中国医学   12篇
肿瘤学   1188篇
  2023年   124篇
  2022年   89篇
  2021年   404篇
  2020年   237篇
  2019年   317篇
  2018年   390篇
  2017年   356篇
  2016年   382篇
  2015年   355篇
  2014年   462篇
  2013年   488篇
  2012年   834篇
  2011年   847篇
  2010年   443篇
  2009年   366篇
  2008年   598篇
  2007年   666篇
  2006年   576篇
  2005年   537篇
  2004年   428篇
  2003年   386篇
  2002年   318篇
  2001年   106篇
  2000年   75篇
  1999年   98篇
  1998年   41篇
  1997年   45篇
  1996年   29篇
  1995年   28篇
  1994年   29篇
  1993年   23篇
  1992年   57篇
  1991年   47篇
  1990年   37篇
  1989年   38篇
  1988年   25篇
  1987年   16篇
  1986年   25篇
  1985年   41篇
  1984年   27篇
  1983年   19篇
  1982年   7篇
  1981年   8篇
  1980年   10篇
  1979年   7篇
  1978年   9篇
  1974年   7篇
  1971年   6篇
  1970年   7篇
  1968年   7篇
排序方式: 共有10000条查询结果,搜索用时 156 毫秒
1.
International Journal of Clinical Oncology - The practice of cancer diagnosis disclosure to children has been changed with the times. The regulations of clinical trials in the 2000s might change...  相似文献   
2.
Background

Osimertinib is effective in patients with T790M mutation-positive advanced non-small-cell lung cancer (NSCLC) resistant to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). However, its effectiveness and safety in patients with poor performance status (PS) are unknown.

Methods

Enrolled patients showed disease progression after treatment with gefitinib, erlotinib, or afatinib; T790M mutation; stage IIIB, IV, or recurrent disease; and PS of 2–4. Osimertinib was orally administered at a dose of 80 mg/day. The primary endpoint of this phase II study (registration, jRCTs061180018) was response rate and the secondary endpoints were progression-free survival (PFS), overall survival (OS), disease control rate, and safety.

Results

Thirty-three patients were enrolled, of which 69.7% and 24.2% had PS of 2 and 3, respectively. One patient was excluded due to protocol violation; in the remaining 32 patients, the response rate was 53.1%; disease control rate was 75.0%; PFS was 5.1 months; and OS was 10.0 months. The most frequent adverse event of grade 3 or higher severity was lymphopenia (12.1%). Interstitial lung disease (ILD) was observed at all grades and at grades 3–5 in 15.2% (5/33) and 6.1% (2/33) of patients, respectively. Treatment-related death due to ILD occurred in one patient. Patients negative for activating EGFR mutations after osimertinib administration had longer median PFS than those positive for these mutations.

Conclusion

Osimertinib was sufficiently effective in EGFR-TKI-resistant, poor PS patients with T790M mutation-positive advanced NSCLC. Plasma EGFR mutation clearance after TKI treatment could predict the response to EGFR-TKIs.

  相似文献   
3.
4.
5.
Claudins are the major component of tight junctions, which form a primary barrier to paracellular diffusion and maintain cell polarity in normal epithelia and endothelia. In cancer cells, claudins play additional roles besides serving as components of the tight junctions, and participate in anoikis or invasion. Among the claudin family proteins, claudin‐1 has the most promising potential, both diagnostically and prognostically, in many types of cancers, including oral, gastric, liver, and colon cancers. However, conflicting results have been reported in relation to the degree of claudin‐1 expression and the prognosis, suggesting that the expression level of claudin‐1 alone is not sufficient to analyze the relationship between claudin‐1 and cancer progression. As endocytic trafficking of claudin‐1 has been reported in several epithelial cell types in vitro, we aimed to determine whether intracellular localization of claudin‐1 is the missing aspect between claudin‐1 and cancer. We investigated the expression of claudin‐1 in 83 tongue squamous cell carcinoma (TSCC) pathological specimens. Although the expression level of claudin‐1 based on immunohistochemistry was not associated with TSCC progression, within the high claudin‐1 expression group, the incidence of intracellular localization of claudin‐1 was correlated with cervical lymph node metastasis. In an in vitro experiment, claudin‐1 was constitutively internalized in TSCC‐derived cells. Motility of TSCC‐derived cells was increased by deficiency of claudin‐1, suggesting that the decrease in cell‐surface claudin‐1 promoted the cell migration. Therefore, intracellular localization of claudin‐1 at the invasion front may represent a promising diagnostic marker of TSCC.  相似文献   
6.
7.
8.
Objective: Quadriceps dysfunction has been suggested as a complication after medial patellofemoral ligament (MPFL) reconstruction. The purpose of this study was to investigate changes in knee extensor strength before and after MPFL reconstruction.

Methods: Twenty patients who underwent MPFL reconstruction for unilateral recurrent patellar dislocation (18 females and 2 males; mean age 20.8 ± 7.6 years) were examined. The peak isometric torque at 60° and 90° of knee flexion and isokinetic knee extensor strength at speeds of 60°/s and 90°/s in operated and non-operated legs were measured using a dynamometer preoperatively and 6 months, 1 year, and 2 years postoperatively. The following parameters were evaluated: (1) body weight-adjusted muscle strength, (2) improvement index (post-/preoperative value × 100) (%), and (3) extensor strength ratio (operated/non-operated value × 100) (%).

Results: The mean knee extensor strength in both operated and non-operated legs significantly increased 2 years after surgery compared with that before surgery. At 2 years postoperatively, the improvement indexes of the isometric knee extensor strength at 60° and 90° and of the isokinetic knee extensor strength at 60°/s and 90°/s were 237%, 192%, 318%, and 186%, respectively, in the operated legs and 144%, 124%, 140%, and 140%, respectively, in the non-operated legs. At 2 years postoperatively, the mean isometric knee extensor strength ratios at 60° and 90° and the isokinetic knee extensor strength ratios at 60°/s and 180°/s were 81%, 84%, 81%, and 82%, respectively.

Conclusions: Knee extensor strength was improved in most patients after MPFL reconstruction, at least compared with that before surgery, although an approximately 20% deficit against the non-operated legs remained even 2 years after surgery.  相似文献   

9.
In this paper, we report two rare cases of foreign body oral injuries caused by forks inserted tightly into both sides of the lingual interdental spaces between the mandibular deciduous canines and first deciduous molars (FDMs). These pediatric cases of foreign body insertion caused not only soft tissue injuries but also the potential luxation of affected deciduous teeth, i.e., the FDMs in the present cases, during the removal of the object by force.  相似文献   
10.
BackgroundMalnutrition measured by the geriatric nutritional risk index (GNRI) was reported to be associated with poor prognosis for patients with peripheral artery disease (PAD). However, the optimal cut-off value of preprocedural GNRI for critical limb ischemia (CLI) and intermittent claudication (IC) is unknown. We aimed to determine its optimal cut-off value for CLI or IC patients requiring endovascular revascularization.MethodsWe explored data of 2246 patients (CLI: n = 1061, IC: n = 1185) registered in the Tokyo-taMA peripheral vascular intervention research COmraDE (TOMA-CODE) registry, which prospectively enrolled consecutive PAD patients who underwent endovascular revascularization in 34 hospitals in Japan from August 2014 to August 2016. The optimal cut-off values of GNRI were assessed by the survival classification and regression tree (CART) analyses, and the survival curve analyses for major adverse cardiovascular and limb events (MACLEs) were performed for these cut-off values.ResultsIn addition to the first cut-off value of 96.2 in CLI and 85.6 in IC, the survival CART provided an additional cut-off value of 78.2 in CLI and 106.0 in IC for further risk stratification. The survival curve was significantly stratified by the GNRI-based malnutrition status in both CLI [high risk: 47.7% (51/107), moderate: 30.1% (118/392), and low: 10.2% (53/520), log–rank p < 0.001] and IC [high risk: 14.3% (7/49), moderate: 4.5% (29/646), and low: 0.5% (2/407), log–rank p < 0.001]. The multivariate Cox-proportional hazard analysis showed that a higher GNRI was significantly associated with a better outcome in both CLI [hazard ratio (HR) per 1-point increase: 0.97, 95% CI: 0.96–0.98, p < 0.001] and IC (HR: 0.94, 95% CI: 0.91–0.97, p < 0.001).ConclusionsPreprocedural nutritional status significantly stratified future events in patients with PAD. Given that the optimal cut-off value of GNRI in CLI was almost 10-points lower than that of IC, using a disease-specific cut-off value is important for risk stratification.  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