全文获取类型
收费全文 | 708343篇 |
免费 | 84925篇 |
国内免费 | 42877篇 |
专业分类
耳鼻咽喉 | 7461篇 |
儿科学 | 9895篇 |
妇产科学 | 10378篇 |
基础医学 | 72545篇 |
口腔科学 | 15372篇 |
临床医学 | 111379篇 |
内科学 | 109875篇 |
皮肤病学 | 9446篇 |
神经病学 | 42991篇 |
特种医学 | 26069篇 |
外国民族医学 | 368篇 |
外科学 | 74920篇 |
综合类 | 108399篇 |
现状与发展 | 168篇 |
一般理论 | 49篇 |
预防医学 | 55410篇 |
眼科学 | 19798篇 |
药学 | 66400篇 |
653篇 | |
中国医学 | 37823篇 |
肿瘤学 | 56746篇 |
出版年
2024年 | 2575篇 |
2023年 | 13090篇 |
2022年 | 23667篇 |
2021年 | 31269篇 |
2020年 | 27021篇 |
2019年 | 20551篇 |
2018年 | 26253篇 |
2017年 | 25416篇 |
2016年 | 24574篇 |
2015年 | 33989篇 |
2014年 | 43033篇 |
2013年 | 41521篇 |
2012年 | 48080篇 |
2011年 | 53810篇 |
2010年 | 39746篇 |
2009年 | 35484篇 |
2008年 | 37579篇 |
2007年 | 36563篇 |
2006年 | 36917篇 |
2005年 | 34508篇 |
2004年 | 22626篇 |
2003年 | 21116篇 |
2002年 | 17934篇 |
2001年 | 16786篇 |
2000年 | 16546篇 |
1999年 | 17737篇 |
1998年 | 11879篇 |
1997年 | 11573篇 |
1996年 | 9517篇 |
1995年 | 8733篇 |
1994年 | 6893篇 |
1993年 | 4739篇 |
1992年 | 5635篇 |
1991年 | 4870篇 |
1990年 | 4167篇 |
1989年 | 3725篇 |
1988年 | 3151篇 |
1987年 | 2691篇 |
1986年 | 2268篇 |
1985年 | 1787篇 |
1984年 | 1101篇 |
1983年 | 908篇 |
1982年 | 583篇 |
1981年 | 570篇 |
1980年 | 410篇 |
1979年 | 423篇 |
1978年 | 272篇 |
1977年 | 255篇 |
1974年 | 214篇 |
1972年 | 187篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
171.
172.
Haya Mohammed BSc MChB M. Yousuf Salmasi MRCS Massimo Caputo PhD Gianni D. Angelini PhD Hunaid A. Vohra PhD 《Journal of cardiac surgery》2020,35(6):1209-1219
Background
Limited data exists demonstrating the efficacy of minimally invasive surgery (MIS) compared to median sternotomy (MS) for multiple valvular disease (MVD). This systematic review and meta-analysis aims to compare operative and peri-operative outcomes of MIS vs MS in MVD.Methods
PubMed, Ovid, and Embase were searched from inception until August 2019 for randomized and observational studies comparing MIS and MS in patients with MVD. Clinical outcomes of intra- and postoperative times, reoperation for bleeding and surgical site infection were evaluated.Results
Five observational studies comparing 340 MIS vs 414 MS patients were eligible for qualitative and quantitative review. The quality of evidence assessed using the Newcastle-Ottawa scale was good for all included studies. Meta-analysis demonstrated increased cardiopulmonary bypass time for MIS patients (weighted mean difference [WMD], 0.487; 95% confidence interval [CI], 0.365-0.608; P < .0001). Similarly, aortic cross-clamp time was longer in patients undergoing MIS (WMD, 0.632; 95% CI, 0.509-0.755; P < .0001). No differences were found in operative mortality, reoperation for bleeding, surgical site infection, or hospital stay.Conclusions
MIS for MVD have similar short-term outcomes compared to MS. This adds value to the use of minimally invasive methods for multivalvular surgery, despite conferring longer operative times. However, the paucity in literature and learning curve associated with MIS warrants further evidence, ideally randomized control trials, to support these findings.173.
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
174.
175.
176.
177.
Platelet function has been described by many laboratory assays, and PL-11 is a new point-of-care platelet function analyzer based on platelet count drop method, which counts platelet before and after the addition of agonists in the citrated whole blood samples. The present study sought to compare PL-11 with other three major more established assays, light transmission aggregometry (LTA), VerifyNow? aspirin system and thromboelastography (TEG), for monitoring the short-term aspirin responses in healthy individuals. Ten healthy young men took 100?mg/d aspirin for 3-day treatment. Platelet function was measured via PL-11, LTA, VerifyNow and TEG, respectively. The blood samples were collected at baseline, 2 hour, 1 day during the aspirin treatment and 1 day, 5?±?1 days, 8?±?1 days after the aspirin withdrawal. Moreover, 90 additional healthy subjects were recruited to establish a reference range for PL-11. Platelet function of healthy subjects decreased significantly 2 hours after 100?mg/d aspirin intake and began to recover during 4–6 days after the aspirin withdrawal. Correlations between methods were PL-11 vs. LTA (r?=?0.614, p?<?0.01); PL-11 vs. VerifyNow (r?=?0.829, p?<?0.01); PL-11 vs. TEG (r?=?0.697, p?<?0.001). There was no significant bias between PL-11 and LTA at baseline (bias?=?1.94%, p?=?0.804) using Bland-Altman analysis, while the data of PL-11 were significantly higher than LTA (bias?=?24.02%, p?<?0.001) during the aspirin therapy. The reference range for PL-11 in healthy young individuals was from 66.8 to 90.5% (95%CI). When aspirin low-responsiveness was defined as LTA?>?20%, the cut-off values for each method were, respectively: PL-11?>?50%, VerifyNow?>?533 ARU, TEG?>?60.2%. The results of different platelet function assays were uninterchangeable for monitoring aspirin response and correlations among them were also varied. Correlations among PL-11 and other three major assays suggested the ability of PL-11 to assess the treatment effects of aspirin. But a large cohort study is needed to confirm the cut-off value of aspirin response detected by PL-11. 相似文献
178.
Factors predicting the development of pressure ulcers in an at‐risk population who receive standardized preventive care: secondary analyses of a multicentre randomised controlled trial
下载免费PDF全文
![点击此处可从《Journal of advanced nursing》网站下载免费的PDF全文](/ch/ext_images/free.gif)
179.
180.