全文获取类型
收费全文 | 1446600篇 |
免费 | 106711篇 |
国内免费 | 11784篇 |
专业分类
耳鼻咽喉 | 20661篇 |
儿科学 | 41288篇 |
妇产科学 | 39767篇 |
基础医学 | 200268篇 |
口腔科学 | 41586篇 |
临床医学 | 127975篇 |
内科学 | 279032篇 |
皮肤病学 | 31317篇 |
神经病学 | 112252篇 |
特种医学 | 57812篇 |
外国民族医学 | 513篇 |
外科学 | 219566篇 |
综合类 | 51390篇 |
现状与发展 | 46篇 |
一般理论 | 442篇 |
预防医学 | 99743篇 |
眼科学 | 34639篇 |
药学 | 111817篇 |
99篇 | |
中国医学 | 9994篇 |
肿瘤学 | 84888篇 |
出版年
2021年 | 13513篇 |
2018年 | 15760篇 |
2017年 | 13204篇 |
2016年 | 14019篇 |
2015年 | 17158篇 |
2014年 | 23153篇 |
2013年 | 30913篇 |
2012年 | 41240篇 |
2011年 | 43978篇 |
2010年 | 26505篇 |
2009年 | 24763篇 |
2008年 | 39383篇 |
2007年 | 42412篇 |
2006年 | 42847篇 |
2005年 | 41718篇 |
2004年 | 38750篇 |
2003年 | 37464篇 |
2002年 | 36474篇 |
2001年 | 65965篇 |
2000年 | 67830篇 |
1999年 | 58167篇 |
1998年 | 16538篇 |
1997年 | 15426篇 |
1996年 | 14451篇 |
1995年 | 13655篇 |
1994年 | 12707篇 |
1992年 | 43644篇 |
1991年 | 41976篇 |
1990年 | 41141篇 |
1989年 | 40083篇 |
1988年 | 37422篇 |
1987年 | 36786篇 |
1986年 | 35226篇 |
1985年 | 33334篇 |
1984年 | 24922篇 |
1983年 | 21137篇 |
1982年 | 12713篇 |
1979年 | 23968篇 |
1978年 | 17068篇 |
1977年 | 14834篇 |
1976年 | 13386篇 |
1975年 | 15267篇 |
1974年 | 18081篇 |
1973年 | 17560篇 |
1972年 | 16810篇 |
1971年 | 15717篇 |
1970年 | 14914篇 |
1969年 | 14346篇 |
1968年 | 13460篇 |
1967年 | 12015篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
人类微生物群是由寄生在人体上皮屏障的细菌和其他微生物组成的,其中大部分位于肠道内,与宿主之间形成共生的关系。机体肠道微生物的组成虽然受到年龄、饮食、生活方式等因素的影响,但在正常生理情况下是相对稳定的。近年来,肠道菌群与恶性肿瘤的关系越来越受到重视。肠道菌群不但能够维持局部稳态,还能调节机体代谢、炎症和免疫等生理过程。有研究表明,微生物群,特别是肠道菌群能够显著调节机体对癌症治疗的反应性以及机体对毒副反应的敏感性。检查肠道菌群中各菌种之间的比例可作为筛查恶性肿瘤的新方法。本文将综述微生物群具有影响肿瘤的发生发展、抗肿瘤治疗疗效以及药物不良反应的证据,以及其中所涉及的微生物种类,从而为恶性肿瘤精准治疗提供证据。 相似文献
72.
73.
74.
75.
76.
77.
Paul J. Devlin Brian W. McCrindle James K. Kirklin Eugene H. Blackstone William M. DeCampli Christopher A. Caldarone Ali Dodge-Khatami Pirooz Eghtesady James M. Meza Peter J. Gruber Kristine J. Guleserian Bahaaladin Alsoufi Linda M. Lambert James E. OBrien Erle H. Austin Jeffrey P. Jacobs Tara Karamlou 《The Journal of thoracic and cardiovascular surgery》2019,157(2):684-695.e8
Objective
Arch obstruction after the Norwood procedure is common and contributes to mortality. We determined the prevalence, associated factors, and practice variability of arch reintervention and assessed whether arch reintervention is associated with mortality.Methods
From 2005 to 2017, 593 neonates in the Congenital Heart Surgeons' Society Critical Left Heart Obstruction cohort underwent a Norwood procedure. Median follow-up was 3.7 years. Multivariable parametric models, including a modulated renewal analysis, were performed.Results
Of the 593 neonates, 146 (25%) underwent 218 reinterventions for arch obstruction after the Norwood procedure: catheter-based (n = 168) or surgical (n = 50) at a median age of 4.3 months (quartile 1-quartile 3, 2.6-5.7). Interdigitation of the distal aortic anastomosis was protective against arch reintervention. Development of ≥ moderate tricuspid valve regurgitation and right ventricular dysfunction at any point was associated with arch reintervention. Nonsignificant variables for arch reintervention included shunt type and preoperative aortic measurements. Surgical arch reintervention was protective against arch reintervention, but transcatheter reintervention was associated with increased reintervention. Arch reintervention was not associated with increased mortality. There was wide institutional variation in incidence of arch reintervention (range, 0-40 reinterventions per 100 years patient follow-up) and in preintervention gradient (range, 0-64 mm Hg).Conclusions
Interdigitation of the distal aortic anastomosis during the Norwood procedure decreased the risk of arch reintervention. Surgical arch reintervention is more definitive than transcatheter. Arch reintervention after the Norwood procedure is not associated with increased mortality. Serial surveillance for arch obstruction, integrated with changes in right ventricular function and tricuspid valve regurgitation, is recommended after the Norwood procedure to improve outcomes. 相似文献78.
To evaluate the anthropometric indexes in subjects with varicocele compared to controls and the incidence of varicocele in different body mass index (BMI) groups for the purpose of exploring the association between varicocele and anthropometric indexes. A comprehensive literature search was conducted by using PubMed, MEDLINE, EMBASE databases and Cochrane Library up to February 2019. A systematic review and meta‐analysis was conducted by STATA, and Newcastle–Ottawa Scale was utilised for assessing risk of bias. Ultimately, 13 articles containing seven case–control studies and six cross‐sectional studies with 1,385,630 subjects were involved in our study. Pooled results demonstrated that varicocele patients had a lower BMI (WMD = ?0.77, 95% CI = ?1.03 to ?0.51) and a higher height than nonvaricocele participants, especially in grade 3 varicocele patients. Subgroup analyses showed that normal BMI individuals had a higher risk of varicocele than obese or overweight individuals and a lower risk than underweight individuals. In conclusion, this study indicates that varicocele patients have a lower BMI and a higher height than nonvaricocele participants. Moreover, men with excess bodyweight have a lower incidence of varicocele compared to normal weight or underweight people. That is to say, high BMI and adiposity protect against varicocele and high BMI is associated with a decreased risk of varicocele. 相似文献
79.
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
80.