全文获取类型
收费全文 | 61524篇 |
免费 | 6580篇 |
国内免费 | 4442篇 |
专业分类
耳鼻咽喉 | 707篇 |
儿科学 | 795篇 |
妇产科学 | 687篇 |
基础医学 | 5686篇 |
口腔科学 | 1364篇 |
临床医学 | 7641篇 |
内科学 | 7579篇 |
皮肤病学 | 539篇 |
神经病学 | 2409篇 |
特种医学 | 2356篇 |
外国民族医学 | 20篇 |
外科学 | 5898篇 |
综合类 | 13822篇 |
现状与发展 | 13篇 |
一般理论 | 2篇 |
预防医学 | 5375篇 |
眼科学 | 1277篇 |
药学 | 7371篇 |
91篇 | |
中国医学 | 4666篇 |
肿瘤学 | 4248篇 |
出版年
2024年 | 320篇 |
2023年 | 1136篇 |
2022年 | 2795篇 |
2021年 | 3435篇 |
2020年 | 2678篇 |
2019年 | 1943篇 |
2018年 | 2023篇 |
2017年 | 2040篇 |
2016年 | 1823篇 |
2015年 | 3002篇 |
2014年 | 3620篇 |
2013年 | 3708篇 |
2012年 | 5208篇 |
2011年 | 5411篇 |
2010年 | 4173篇 |
2009年 | 3524篇 |
2008年 | 3771篇 |
2007年 | 3770篇 |
2006年 | 3390篇 |
2005年 | 2749篇 |
2004年 | 2381篇 |
2003年 | 2324篇 |
2002年 | 1981篇 |
2001年 | 1536篇 |
2000年 | 1048篇 |
1999年 | 642篇 |
1998年 | 383篇 |
1997年 | 376篇 |
1996年 | 261篇 |
1995年 | 222篇 |
1994年 | 201篇 |
1993年 | 115篇 |
1992年 | 108篇 |
1991年 | 90篇 |
1990年 | 95篇 |
1989年 | 66篇 |
1988年 | 49篇 |
1987年 | 44篇 |
1986年 | 38篇 |
1985年 | 20篇 |
1984年 | 17篇 |
1983年 | 11篇 |
1981年 | 3篇 |
1980年 | 3篇 |
1979年 | 3篇 |
1974年 | 2篇 |
1972年 | 1篇 |
1971年 | 3篇 |
1970年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
Near-infrared diffuse correlation spectroscopy/tomography (DCS/DCT) has recently emerged as a noninvasive measurement/imaging technology for tissue blood flow. In DCT studies, the high-dense collection of light temporal autocorrelation curves (g2(τ)) via fiber array are critical for image reconstruction of blood flow. Previously, the camera-based fiber array limits the field of view (FOV), precluding its applications on large-size human tissues. The line-shape fiber probe based on lens combination, which is predominantly used in current DCT studies, requires rotated-scanning over the surface of target tissue, substantially prolonging the measurement time and increasing the system instability. In this study, we design a noncontact optical probe for DCT based on collimating micro-lens fiber array, termed as FA-nc-DCT system. For each source/detector fiber, a single optical path was collimated by coupling with one micro-lens in the fiber array that is integrated in a square-shape base. Additionally, an 8×8 optical switch is used to share the hardware laser and detectors without spatial scanning. The FA-nc approach for the precise collection of g2(τ) curves was validated through a speed-varied phantom experiment and the human experiments of cuff occlusion, from which the expected value of the blood flow index (BFI) was obtained. Furthermore, the flow anomaly in the phantom and the ischemic muscle in human were accurately reconstructed from the FA-nc-DCT system, which is combined with the imaging framework based on the Nth-order linear algorithm that we recently created. Those outcomes demonstrated the great potential of FA-nc-DCT technology for fast and robust imaging of various diseases such as human breast cancers. 相似文献
3.
4.
5.
Sophocarpine attenuates toll‐like receptor 4 in steatotic hepatocytes to suppress pro‐inflammatory cytokines synthesis
下载免费PDF全文
![点击此处可从《Journal of gastroenterology and hepatology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
6.
7.
8.
Shengxuan Cao Chen Wang Xin Ma Xu Wang Jiazhang Huang Chao Zhang Li Chen Xiang Geng Kan Wang 《Journal of orthopaedic research》2019,37(8):1860-1867
Patients with mechanic ankle instability experience increased tibiotalar and subtalar joint laxity. However, in vivo joint kinematics in functional ankle instability (FAI) patients and lateral ankle sprain (LAS) copers, especially during dynamic activities, are poorly understood. Ten FAI patients, 10 LAS copers, and 10 healthy controls were included in this study. A dual fluoroscopic imaging system was used to analyze the tibiotalar and subtalar joint kinematics during stair descent. Five key poses of stair descent were analyzed. Kinematic data from six degrees of freedom were calculated utilizing a solid modeling software. The range of motion and joint positions in each degree of freedom were compared among the three groups. The tibiotalar joints of FAI patients and LAS copers were significantly more inverted than those of healthy controls during the foot strike (p = 0.016, = 0.264). The subtalar joints of FAI patients were significantly more anteriorly translated (pose 2, p = 0.003, = 0.352; pose 3, p < 0.001, = 0.454; pose 4, p = 0.004, = 0.334), inverted (pose 4, p = 0.027, = 0.234; pose 5,p = 0.034, = 0.221), and externally rotated (pose 4, p = 0.037, = 0.217; pose 5; p = 0.004, = 0.331) than those of healthy controls during the mid‐stance and the heel off. The FAI patients showed excessive tibiotalar inversion and subtalar joint hypermobility during stair descent. Meanwhile, the LAS copers maintained subtalar joint stability, and only showed excessive tibiotalar inversion in foot strike. These data provide insight into the mechanisms behind the development of FAI after initial LAS. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1860–1867, 2019 相似文献
9.
10.