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   10587篇
  免费   650篇
  国内免费   81篇
耳鼻咽喉   84篇
儿科学   332篇
妇产科学   181篇
基础医学   1303篇
口腔科学   461篇
临床医学   935篇
内科学   2486篇
皮肤病学   264篇
神经病学   909篇
特种医学   484篇
外科学   1697篇
综合类   18篇
一般理论   1篇
预防医学   579篇
眼科学   94篇
药学   487篇
中国医学   11篇
肿瘤学   992篇
  2023年   127篇
  2022年   95篇
  2021年   433篇
  2020年   212篇
  2019年   338篇
  2018年   417篇
  2017年   275篇
  2016年   280篇
  2015年   312篇
  2014年   411篇
  2013年   488篇
  2012年   706篇
  2011年   782篇
  2010年   451篇
  2009年   432篇
  2008年   677篇
  2007年   655篇
  2006年   612篇
  2005年   594篇
  2004年   537篇
  2003年   489篇
  2002年   392篇
  2001年   200篇
  2000年   172篇
  1999年   144篇
  1998年   84篇
  1997年   72篇
  1996年   55篇
  1995年   49篇
  1994年   43篇
  1993年   44篇
  1992年   81篇
  1991年   68篇
  1990年   59篇
  1989年   52篇
  1988年   56篇
  1987年   50篇
  1986年   44篇
  1985年   43篇
  1984年   28篇
  1983年   37篇
  1982年   23篇
  1981年   15篇
  1980年   15篇
  1979年   20篇
  1977年   17篇
  1975年   16篇
  1974年   13篇
  1973年   14篇
  1968年   14篇
排序方式: 共有10000条查询结果,搜索用时 171 毫秒
1.
We review the spectrum of cutaneous disorders associated with inflammatory and neoplastic plasmacytic pathology. Because plasma cells are derived from B‐lymphocytes our overview includes discussion of certain lymphoplasmacytic proliferations. It is structured along histopathological lines, addressing conditions characterized by (a) cutaneous plasma cell infiltrates, (b) deposits of plasma cell products or their derivatives in the skin and (c) miscellaneous, poorly understood cutaneous complications of plasmacytic disorders. Lesions arising primarily in the skin and those due to cutaneous involvement by multisystem disorders are addressed. The range includes a spectrum of tumefactive and circulatory manifestations. We highlight key clinical and pathological features of the different conditions and outline recent advances in our understanding of these entities. By emphasizing the dermatopathological characteristics of this spectrum of disorders we hope to hone the diagnostic accuracy of practitioners in the field.  相似文献   
2.
3.
4.
5.
6.
7.
Introduction: Recently, a new minimally invasive single bundle technique for anatomic ACL reconstruction has been described, called the ‘All-Inside graft-link technique’. One of the advantages of this procedure is the reduced morbidity at the donor site as the graft choice is the quadrupled semitendinosus, thus sparing the gracilis tendon. The aim of this study was to evaluate isokinetic flexion strength recovery in patients who underwent a gracilis sparing technique compared to those with a full-tibial tunnel technique using a doubled gracilis and semitendinosus tendons (DGST) graft.

Methods: Patients were divided into two groups: Group A (22 patients) who underwent ACL reconstruction performed with an All-Inside graft-link technique; Group B (22 patients) who underwent ACL reconstruction with an Out-In technique and DGST graft. At a mean follow-up of 13 months, quadriceps and hamstring isokinetic peak torque deficits were recorded.

Results: In group A, the mean side to side peak torque flexion difference between the operated and non-operated limbs was ?3% and the mean torque at 30° was ?7.5% at high angular velocity (180°/sec); the mean peak flexion torque was 7.2% and the mean torque at 30° was 3.1% at low angular velocity (60°/sec).

In group B, the mean side to side peak flexion torque was ?3.5% and the mean torque at 30° was ?7.6% at high angular velocity (180°/sec); the mean peak flexion torque was ?7.2% and the mean torque at 30° was ?11% at low angular velocity (60°/sec).

A statistically significant difference was found between the two groups at lower angular velocity both for the mean peak flexion torque and the mean torque at 30° (= 0.009), with better results in the study group.

Discussion/conclusion: Gracilis sparing technique is a minimally invasive technique for ACL reconstruction and yielded a significantly better flexion strength recovery at lower angular velocity compared to a full tibial tunnel technique with DGST for ACL reconstruction.  相似文献   

8.
9.
Unresectable neuroendocrine neoplasms (NENs) often poorly respond to standard therapeutic approaches. Alkylating agents, in particular temozolomide, commonly used to treat high-grade brain tumors including glioblastomas, have recently been tested in advanced or metastatic NENs, where they showed promising response rates. In glioblastomas, prediction of response to temozolomide is based on the assessment of the methylation status of the MGMT gene, as its product, O6 -methylguanine-DNA methyltransferase, may counteract the damaging effects of the alkylating agent. However, in NENs, such a biomarker has not been validated yet. Thus, we have investigated MGMT methylation in 42 NENs of different grades and from various sites of origin by two different approaches: in contrast to methylation-specific PCR (MSP), which is commonly used in glioblastoma management, amplicon bisulfite sequencing (ABS) is based on high-resolution, next-generation sequencing and interrogates several additional CpG sites compared to those covered by MSP. Overall, we found MGMT methylation in 74% (31/42) of the NENs investigated. A higher methylation degree was observed in welldifferentiated tumors and in tumors originating in the gastrointestinal tract. Comparing MSP and ABS results, we demonstrate that the region analyzed by the MSP test is sufficiently informative of the MGMT methylation status in NENs, suggesting that this predictive parameter could routinely be interrogated also in NENs.  相似文献   
10.
Background:Cardiovascular diseases (CVD), particularly the ischemic heart disease, are a growing public health issue. In addition, the return to work after an acute cardiovascular attack represents a complex challenge.Objectives:To evaluate utility and safety of cardiopulmonary exercise testing (CPET), particularly performed “on site”, to promote a return to work in line with the residual working capacity.Methods:Fifty-nine workers affected by a major cardiovascular event, aged 18-63 years, have been enrolled between 2015 and 2018. All the patients underwent a CPET in outpatient clinic. Eleven workers also underwent the “on site” CPET, recorded during their working activities.Results:Outpatient clinic CPET outcomes (i.e. normal, mild impairment or moderate/severe impairment of cardiopulmonary function) were associated with the subjective perception of workers’ health status after returning to work. The “on site” CPET was found to be safe and reliable to promote a personalized return to work of patients. In 7 out of 11 patients, the values of O2 consumption (VO2) during the working activity were higher than 40% of VO2 max as obtained from laboratory CPET.Conclusions:This study provides evidence for safety and usefulness of “on site” CPET for a personalized statement of fitness for work. This may facilitate the job retention of patients characterized by a high risk of unnecessary job loss. The use of CPET represents a first step of energy expenditure evaluation associated with specific working tasks.Key words: Acute coronary syndrome, cardiopulmonary exercise testing, return to work  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