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   10197393篇
  免费   640719篇
  国内免费   161532篇
耳鼻咽喉   132501篇
儿科学   284984篇
妇产科学   234494篇
基础医学   1265498篇
口腔科学   268560篇
临床医学   1032078篇
内科学   1710619篇
皮肤病学   205664篇
神经病学   736172篇
特种医学   380279篇
外国民族医学   1837篇
外科学   1344780篇
综合类   712332篇
现状与发展   513篇
一般理论   3834篇
预防医学   823340篇
眼科学   233607篇
药学   869932篇
  2805篇
中国医学   210049篇
肿瘤学   545766篇
  2022年   131492篇
  2021年   200717篇
  2020年   143227篇
  2019年   146286篇
  2018年   178371篇
  2017年   158722篇
  2016年   152966篇
  2015年   189760篇
  2014年   277914篇
  2013年   370351篇
  2012年   522887篇
  2011年   567148篇
  2010年   384356篇
  2009年   345851篇
  2008年   483191篇
  2007年   503526篇
  2006年   481043篇
  2005年   443027篇
  2004年   389758篇
  2003年   361448篇
  2002年   333422篇
  2001年   314264篇
  2000年   313039篇
  1999年   268220篇
  1998年   111880篇
  1997年   98445篇
  1996年   92487篇
  1995年   84639篇
  1994年   76709篇
  1993年   65717篇
  1992年   184922篇
  1991年   178901篇
  1990年   173691篇
  1989年   168609篇
  1988年   156016篇
  1987年   152079篇
  1986年   144832篇
  1985年   138181篇
  1984年   105426篇
  1983年   90501篇
  1982年   57863篇
  1979年   95094篇
  1978年   68229篇
  1977年   58999篇
  1976年   54751篇
  1975年   59832篇
  1974年   69289篇
  1973年   66225篇
  1972年   61372篇
  1971年   56908篇
排序方式: 共有10000条查询结果,搜索用时 8 毫秒
1.
ABSTRACT

The lack of stable housing can impair access and continuity of care for patients living with human immunodeficiency virus (HIV). This study investigated the relationship between housing status assessed at multiple time points and several core HIV-related outcomes within the same group of HIV patients experiencing homelessness. Patients with consistently stable housing (CSH) during the year were compared to patients who lacked CSH (non-CSH group). The study outcomes included HIV viral load (VL), CD4 counts, and health care utilization. Multivariable and propensity weighted analyses were used to assess outcomes adjusting for potential group differences. Of 208 patients, 88 (42%) had CSH and 120 (58%) were non-CSH. Patients with CSH had significantly higher proportion of VL suppression and higher mean CD4 counts. The frequency of nurse visits in the CSH group was less than a half of that in the non-CSH group. Patients with CSH were less likely to be admitted to the medical respite facility, and if admitted, their length of stay was about a half of that for the non-CSH group. Our study findings show that patients with CSH had significantly better HIV virologic control and immune status as well as improved health care utilization.  相似文献   
2.
Introduction: The landscape of poly (ADP-ribose) polymerase (PARP) inhibition in ovarian cancer is rapidly evolving and becoming increasingly complex. Ovarian cancer is leading therapeutic innovation by providing the proof of concept for DNA repair as a target. Three different PARP inhibitors have now received approvals in the US and Europe in different indications. Subtle but crucial differences can be found among the licensed indications for each PARP inhibitor in terms of histology, type of BRCA mutation (germline and/or somatic), number of prior lines of chemotherapy and whether the indication is in the treatment or maintenance settings.

Areas covered: We review the latest clinical data regarding the PARP inhibitor rucaparib in ovarian cancer, provide an update on the evolving landscape of PARP inhibition in ovarian cancer, and summarize avenues of ongoing and future research.

Expert opinion: All eligible patients should be offered a PARP inhibitor. SOLO1 trial results demonstrated an unprecedented benefit maintenance with PARP inhibitors in first line. Results from trials evaluating PARP inhibitors as maintenance in first line regardless of BRCA status and from trials evaluating combinatorial strategies are eagerly awaited.  相似文献   

3.
4.
穴位埋线是长效针灸,是在传统针具和针法基础上建立和发展起来的,是针灸技术的发展和延伸,穴位埋线的核心技术是穿刺技术,穴位埋线的三大要素中,针具、埋藏物、穿刺技巧之间是互相影响、互相促进的。针具的改进成功实现了穴位埋线疗法的第一次飞跃,埋藏物的改进成功实现了穴位埋线疗法的第二次飞跃,穿刺技术的改进和创新是穴位埋线疗法的第三次飞跃。  相似文献   
5.
6.
7.
8.
Moderate sedatives have been increasingly used to improve patient comfort during flexible bronchoscopy (FB). However, routine use of moderate sedation during FB is controversial because its efficacy and safety are not well established.This study aims to evaluate the efficacy and safety of moderate sedation during FB.A search was made of Medline, EMBASE, and the Cochrane Library to May 2014.Randomized controlled trials (RCTs) and quasi-RCTs were included.The main analysis was designed to examine the efficacy of moderate sedation during FB in sedation than no-sedation.The willingness to repeat FB was significantly more in sedation than no-sedation (odds ratio [OR] 2.30; 95% confidence interval [CI] 1.11–4.73; P = 0.02; I2 = 22.5). The duration of FB was shorter in sedation group than no-sedation group (standardized mean difference [SMD] −0.21; 95% CI −0.38 to −0.03; P = 0.02; I2 = 78.3%). Event of hypoxia was not significantly different between sedation and no-sedation groups (OR 0.86; 95% CI 0.42–1.73; P = 0.67; I2 = 0%). The SpO2 during procedure was not different between sedation and no-sedation groups (SMD −0.14; 95% CI −0.37 to 0.08; P = 0.21; I2 = 49.9%). However, in subgroup analysis without supplemental oxygen, the SpO2 was significantly lower in sedation than no-sedation group (SMD −0.45; 95% CI −0.78 to −0.11; P = 0.01; I2 = 0.0%).According to this meta-analysis, moderate sedation in FB would be useful in patients who will require repeated bronchoscopies as well as safe in respiratory depression. To our knowledge, although the various sedative drugs are already used in the real field, this analysis was the first attempt to quantify objective results. We anticipate more definite and studies designed to elucidate standardized outcomes for moderate sedation in FB.  相似文献   
9.
The present study aimed at examining the curative effect of modified posterior operation on treatment of Kümmell''s disease.About 30 patients of Kümmell''s disease with complete image and clinical data treated during June 2004 to July 2013 were conducted with anterior and posterior approaches, respectively. Kyphotic Cobb angle, fractured vertebra wedge angle, and the anterior and posterior heights of fractured vertebra were all measured through x-ray before and after operation, and the pain visual analog scale (VAS) was determined for evaluating the effect of operations. The injury and restoration of neurological function were assessed using Frankel classification.Patients in group A were treated with anterior operation, whereas group B was posterior operation. Postoperatively, VAS score, kyphotic Cobb angle, anterior vertebra height, and pathologic vertebra wedge angle were all significantly improved in patients with Kümmell''s disease receiving modified posterior operation (group B). Similar results were also observed in patients with anterior operation. The improvement of VAS and correction rate of kyphotic Cobb angle indicated equivalent effects of posterior and anterior operations. Meanwhile, alleviated neurological function damage was observed in 2 groups. Relevant factor analysis illustrated that there was no significant correlation of the severity and improvement rate of pain symptoms with age, medical history, anterior and posterior vertebra heights, kyphotic Cobb angle, and pathological vertebra wedge angle.Compared with traditional anterior approach, modified posterior operation, adopting transpedicular vertebral body grafting combined with vertebral pedicle screw fixation, could produce equivalent effects on kyphosis correction, pain relief, and improvement of neurological function in patients with Kümmell''s disease.  相似文献   
10.
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