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   35469篇
  免费   2048篇
  国内免费   362篇
耳鼻咽喉   573篇
儿科学   385篇
妇产科学   476篇
基础医学   5874篇
口腔科学   920篇
临床医学   2966篇
内科学   6730篇
皮肤病学   1415篇
神经病学   2543篇
特种医学   2311篇
外国民族医学   1篇
外科学   4382篇
综合类   174篇
一般理论   6篇
预防医学   1660篇
眼科学   599篇
药学   3523篇
  13篇
中国医学   471篇
肿瘤学   2857篇
  2024年   103篇
  2023年   299篇
  2022年   811篇
  2021年   1312篇
  2020年   610篇
  2019年   845篇
  2018年   1022篇
  2017年   847篇
  2016年   1228篇
  2015年   1619篇
  2014年   1915篇
  2013年   2173篇
  2012年   3261篇
  2011年   3194篇
  2010年   1825篇
  2009年   1593篇
  2008年   2202篇
  2007年   1999篇
  2006年   1791篇
  2005年   1643篇
  2004年   1304篇
  2003年   1134篇
  2002年   957篇
  2001年   803篇
  2000年   732篇
  1999年   530篇
  1998年   215篇
  1997年   136篇
  1996年   119篇
  1995年   83篇
  1994年   96篇
  1993年   79篇
  1992年   149篇
  1991年   155篇
  1990年   174篇
  1989年   137篇
  1988年   121篇
  1987年   112篇
  1986年   96篇
  1985年   65篇
  1984年   44篇
  1983年   40篇
  1982年   28篇
  1981年   36篇
  1979年   23篇
  1978年   22篇
  1977年   24篇
  1975年   18篇
  1974年   17篇
  1970年   24篇
排序方式: 共有10000条查询结果,搜索用时 20 毫秒
91.
92.

Background

The purpose of this study was to evaluate the screw-home movement at the tibiofemoral joint during normal gait by utilizing the 3-dimensional motion capture technique.

Methods

Fifteen young males and fifteen young females (total 60 knee joints) who had no history of musculoskeletal disease or a particular gait problem were included in this study. Two more markers were attached to the subject in addition to the Helen-Hayes marker set. Thus, two virtual planes, femoral coronal plane (Pf) and tibial coronal plane (Pt), were created by Skeletal Builder software. This study measured the 3-dimensional knee joint movement in the sagittal, coronal, and transverse planes of these two virtual planes (Pf and Pt) during normal gait.

Results

With respect to kinematics and kinetics, both males and females showed normal adult gait patterns, and the mean difference in the temporal gait parameters was not statistically significant (p > 0.05). In the transverse plane, the screw-home movement occurred as expected during the pre-swing phase and the late-swing phase at an angle of about 17°. However, the tibia rotated externally with respect to the femur, rather than internally, while the knee joint started to flex during the loading response (paradoxical screw-home movement), and the angle was 6°.

Conclusions

Paradoxical screw-home movement may be an important mechanism that provides stability to the knee joint during the remaining stance phase. Obtaining the kinematic values of the knee joint during gait can be useful in diagnosing and treating the pathological knee joints.  相似文献   
93.
94.
95.
Parasitology Research - Giardia duodenalis is an important zoonotic protozoan parasite that infects humans and other animals. This study was conducted to investigate the prevalence and molecular...  相似文献   
96.

Background

Whether osteoarthritic patients with mild varus deformity can be indicated for high tibial osteotomy (HTO) is not established. We examined the preoperative characteristics and postoperative outcomes of HTO in patients with mild genu varum compared to patients with greater varus deformity.

Methods

Seventy-one patients who underwent HTO were included in this retrospective study. Patients were divided into either mild varus (MV, mechanical femorotibial angle (mFTA) ≤ 4°, n?=?31 (44%)) and greater varus (GV, mFTA > 4°, n?=?40 (56%)) groups. Preoperative characteristics on single photon emission computed tomography–computed tomography (SPECT–CT), magnetic resonance image and radiograph were evaluated. Alignment parameters and functional outcomes were compared pre- and postoperatively between the groups.

Results

Preoperative characteristics were similar between the two groups, except the severity of arthritis and coronal alignment. There was no difference in the proportion of hot uptake in the medial compartment; medial meniscus posterior horn root tear, complex or radial tear; bone marrow edema. Full-thickness cartilage defect of medial compartment was more frequent and arthritis grade was also more severe in GV group. Coronal alignment of the MV group was corrected into more valgus than the GV group (4.5° vs. 2.8° in mFTA, P?=?0.012). Pre- and postoperative Knee Society knee and function scores were also comparable in the two groups.

Conclusions

Mild varus patients are similar to greater varus patients regarding preoperative features and achieve the comparable functional outcome. A selected subset of osteoarthritic patients with mild varus deformity might be indicated for HTO.

Level of evidence

III (Retrospective comparative study).  相似文献   
97.
98.
We studied the clinical correlations and epitopes of autoantibodies directed to a novel autoantigen, Bicaudal D (BICD2), in systemic sclerosis (SSc) and reviewed its relationship to centromere protein A (CENP-A). 451 SSc sera were tested for anti-BICD2 using a paramagnetic bead immunoassay and then univariate and multivariate logistic regression was used to study the association between anti-BICD2 and demographic and clinical parameters as well as other SSc-related autoantibodies. Epitope mapping was performed on solid phase matrices. 25.7% (116/451) SSc sera were anti-BICD2 positive, of which 19.0% had single specificity anti-BICD2 and 81.0% had other autoantibodies, notably anti-CENP (83/94; 88.3%). Compared to anti-BICD2 negative subjects (335/451), single specificity anti-BICD2 subjects were more likely to have an inflammatory myopathy (IM; 31.8% vs. 9.6%, p = .004) and interstitial lung disease (ILD; 52.4% vs. 29.0%, p = .024). Epitope mapping revealed a serine- and proline-rich nonapeptide SPSPGSSLP comprising amino acids 606–614 of BICD2, shared with CENP-A but not CENP-B. We observed that autoantibodies to BICD2 represent a new biomarker as they were detected in patients without other SSc-specific autoantibodies and were the second most common autoantibody identified in this SSc cohort. Our data indicate that the major cross-reactive epitope is associated with anti-CENP-A but, unlike anti-CENP, single specificity anti-BICD2 antibodies associate with ILD and IM.  相似文献   
99.
100.
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