全文获取类型
收费全文 | 14068篇 |
免费 | 957篇 |
国内免费 | 565篇 |
专业分类
耳鼻咽喉 | 183篇 |
儿科学 | 209篇 |
妇产科学 | 230篇 |
基础医学 | 670篇 |
口腔科学 | 1002篇 |
临床医学 | 1269篇 |
内科学 | 1180篇 |
皮肤病学 | 93篇 |
神经病学 | 383篇 |
特种医学 | 532篇 |
外国民族医学 | 1篇 |
外科学 | 2317篇 |
综合类 | 2091篇 |
预防医学 | 777篇 |
眼科学 | 213篇 |
药学 | 2942篇 |
12篇 | |
中国医学 | 1200篇 |
肿瘤学 | 286篇 |
出版年
2024年 | 33篇 |
2023年 | 231篇 |
2022年 | 361篇 |
2021年 | 489篇 |
2020年 | 476篇 |
2019年 | 415篇 |
2018年 | 453篇 |
2017年 | 367篇 |
2016年 | 437篇 |
2015年 | 418篇 |
2014年 | 909篇 |
2013年 | 912篇 |
2012年 | 902篇 |
2011年 | 998篇 |
2010年 | 812篇 |
2009年 | 751篇 |
2008年 | 742篇 |
2007年 | 838篇 |
2006年 | 753篇 |
2005年 | 669篇 |
2004年 | 538篇 |
2003年 | 445篇 |
2002年 | 325篇 |
2001年 | 301篇 |
2000年 | 236篇 |
1999年 | 209篇 |
1998年 | 156篇 |
1997年 | 148篇 |
1996年 | 162篇 |
1995年 | 132篇 |
1994年 | 135篇 |
1993年 | 111篇 |
1992年 | 91篇 |
1991年 | 84篇 |
1990年 | 56篇 |
1989年 | 75篇 |
1988年 | 46篇 |
1987年 | 50篇 |
1986年 | 34篇 |
1985年 | 61篇 |
1984年 | 44篇 |
1983年 | 31篇 |
1982年 | 31篇 |
1981年 | 23篇 |
1980年 | 28篇 |
1979年 | 16篇 |
1978年 | 12篇 |
1977年 | 14篇 |
1976年 | 14篇 |
1974年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
Guo-Quan Shi Huajun Zhu & Zhen-Guo Yan 《Communications In Computational Physics》2022,31(4):1215-1241
A priori subcell limiting approach is developed for high-order flux reconstruction/correction procedure via reconstruction (FR/CPR) methods on two-dimensional unstructured quadrilateral meshes. Firstly, a modified indicator based on
modal energy coefficients is proposed to detect troubled cells, where discontinuities
exist. Then, troubled cells are decomposed into nonuniform subcells and each subcell has one solution point. A second-order finite difference shock-capturing scheme
based on nonuniform nonlinear weighted (NNW) interpolation is constructed to perform the calculation on troubled cells while smooth cells are calculated by the CPR
method. Numerical investigations show that the proposed subcell limiting strategy on
unstructured quadrilateral meshes is robust in shock-capturing. 相似文献
4.
5.
6.
目的:调查心脏瓣膜置换术后患者的出院准备度现状,并分析其影响因素。方法:于2018年9月至2019年3月用一般资料、出院准备度量表、出院指导质量量表对139例瓣膜置换术后患者进行调查。结果:心脏瓣膜置换术后患者的出院准备度总分为(89.51±8.53)分,与出院指导质量呈正相关;多元回归分析显示,主要照顾者、婚姻状况、工作状态、服药种类、出院指导质量为出院准备度影响因素。结论:心脏瓣膜置换术后患者的出院准备度有待提高,患者感知的个人状态得分不理想;护士应鼓励患者配合进行早期康复,强化出院指导,采取有效措施提供康复信息,满足患者及其家属需求,提高出院准备度。 相似文献
7.
Susumu Shibasaki Koichi Suda Masaya Nakauchi Kenichi Nakamura Kenji Kikuchi Kazuki Inaba Ichiro Uyama 《World journal of gastroenterology : WJG》2020,26(11):1172-1184
BACKGROUND Minimally invasive surgery for gastric cancer(GC) has gained widespread use as a safe curative procedure especially for early GC.AIM To determine risk factors for postoperative complications after minimally invasive gastrectomy for GC.METHODS Between January 2009 and June 2019, 1716 consecutive patients were referred to our division for primary GC. Among them, 1401 patients who were diagnosed with both clinical and pathological Stage Ⅲ or lower GC and underwent robotic gastrectomy(RG) or laparoscopic gastrectomy(LG) were enrolled. Retrospective chart review and multivariate analysis were performed for identifying risk factors for postoperative morbidity.RESULTS Morbidity following minimally invasive gastrectomy was observed in 7.5% of the patients. Multivariate analyses demonstrated that non-robotic minimally invasive surgery, male gender, and an operative time of ≥ 360 min were significant independent risk factors for morbidity. Therefore, morbidity was compared between RG and LG. Accordingly, propensity-matched cohort analysis revealed that the RG group had significantly fewer intra-abdominal infectious complications than the LG group(2.5% vs 5.9%, respectively; P = 0.038), while no significant differences were noted for other local or systemic complications.Multivariate analyses of the propensity-matched cohort revealed that non-robotic minimally invasive surgery [odds ratio = 2.463(1.070–5.682); P = 0.034] was a significant independent risk factor for intra-abdominal infectious complications.CONCLUSION The findings showed that robotic surgery might improve short-term outcomes following minimally invasive radical gastrectomy by reducing intra-abdominal infectious complications. 相似文献
8.
《Journal of endodontics》2020,46(6):846-857
IntroductionThis study assessed the cleaning, shaping, and disinfection abilities of 2 instrumentation systems in molar root canals using a novel correlative analytical approach.MethodsThe root canals from extracted mandibular and maxillary molars with apical periodontitis were pair matched according to anatomic similarities as determined by micro–computed tomographic analysis and prepared with either XP-endo Shaper (FKG Dentaire, La Chaux-de-Fonds, Switzerland) (n = 16) or Reciproc Blue (VDW, Munich, Germany) (n = 16) instruments and 2.5% sodium hypochlorite irrigation. Pre- and postpreparation micro–computed tomographic scans were used to identify and calculate the unprepared surface areas (shaping), which were histobacteriologically evaluated for the presence of residual bacteria (disinfection) and pulp tissue remnants (cleaning) in each canal third.ResultsUnprepared canal surface areas for XP-endo Shaper and Reciproc Blue in the full canal length were approximately 26% and 19% (P < .05), respectively (30% and 23% in the apical part of the canal, P > .05). Preparation with Reciproc Blue resulted in 37.5% canals free of bacteria in all sections examined and 56% in the apical sections only. XP-endo Shaper resulted in 44% canals free of bacteria in all sections, and 56% in the apical part of the canal only. Pulp tissue remnants were not observed in 31% (all canal sections) and 50% (apical canal sections) of specimens from both instrument systems. No significant differences were observed between instruments when comparing the amount of pulp tissue remnants and the number of cases negative for bacteria and tissue remnants (P > .05).ConclusionsAlthough the Reciproc Blue instrument had superior shaping ability in comparison with XP-endo Shaper, both systems performed similarly in cleaning and disinfecting root canals. Irregular canals and difficult-to-reach areas were not thoroughly cleaned and disinfected by any of the tested systems. 相似文献
9.
Gastro-oesophageal reflux disease (GORD) is symptomatic reflux of gastric contents into the oesophagus. Factors predisposing to GORD are loss of the physiological antireflux barrier and anatomic abnormalities of the oesophagus or diaphragm. Conservative measures and medical management results in resolution of symptoms in a majority of children. Surgery is indicated in the event of failure of medical management or severe complications. Surgical procedures include open or laparoscopic fundoplication in children with normal neurology; fundoplication with or without vagotomy and pyloroplasty; surgical feeding jejunostomy and oesophago-gastric dissociation in the severely neurologically impaired children. 相似文献