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   29118篇
  免费   2508篇
  国内免费   316篇
耳鼻咽喉   387篇
儿科学   446篇
妇产科学   522篇
基础医学   1255篇
口腔科学   306篇
临床医学   4948篇
内科学   2764篇
皮肤病学   391篇
神经病学   1283篇
特种医学   684篇
外科学   2516篇
综合类   4165篇
一般理论   1篇
预防医学   5377篇
眼科学   151篇
药学   3635篇
  21篇
中国医学   1377篇
肿瘤学   1713篇
  2024年   62篇
  2023年   587篇
  2022年   1226篇
  2021年   1498篇
  2020年   1538篇
  2019年   1382篇
  2018年   1274篇
  2017年   1162篇
  2016年   1106篇
  2015年   1069篇
  2014年   2752篇
  2013年   2288篇
  2012年   2114篇
  2011年   2186篇
  2010年   1587篇
  2009年   1598篇
  2008年   1513篇
  2007年   1420篇
  2006年   1132篇
  2005年   899篇
  2004年   690篇
  2003年   517篇
  2002年   386篇
  2001年   318篇
  2000年   298篇
  1999年   264篇
  1998年   174篇
  1997年   172篇
  1996年   139篇
  1995年   132篇
  1994年   94篇
  1993年   91篇
  1992年   63篇
  1991年   54篇
  1990年   35篇
  1989年   22篇
  1988年   23篇
  1987年   14篇
  1986年   6篇
  1985年   18篇
  1984年   12篇
  1983年   5篇
  1982年   7篇
  1981年   7篇
  1980年   2篇
  1979年   2篇
  1976年   1篇
  1975年   1篇
  1972年   1篇
  1970年   1篇
排序方式: 共有10000条查询结果,搜索用时 987 毫秒
41.
BackgroundTo date, no previous studies have evaluated the relationship between sleep duration and quality of life (QOL) or depression in the general population after controlling for daytime sleepiness and sleep disturbances.MethodsA web-based cross-sectional survey was conducted with 8698 subjects aged 20–69 years. We examined the relationships between weekday sleep duration and daytime sleepiness, sleep disturbance, QOL and depression, using the Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index (without the item for sleep duration), 8-item Short Form and Center for Epidemiological Studies Depression Scale (CES-D).ResultsDaytime sleepiness tended to increase in proportion to shorter weekday sleep durations. Sleep disturbances, physical and mental QOL, and CES-D scores were worse in both the shorter and longer sleep groups compared with the group with 7–8 h of sleep. Hierarchical logistic regression analyses revealed that short sleep duration but not long sleep duration was significantly associated with reduction of both physical and mental QOL, even after controlling for the presence of daytime sleepiness and sleep disturbance. Both short and long sleep duration were independently and significantly correlated with depression after controlling for daytime sleepiness; however, there was no statistically significant association after adjusting for the effects of sleep disturbance.ConclusionsThe results suggested adverse effects of short sleep but not long sleep on both physical and mental QOL. In addition, the negative impact of specific types of sleep disturbance on depression may be greater than the impact of shortening of sleep duration.  相似文献   
42.
43.
目的对比分析单纯关节镜手术与关节镜手术联合Ilizarov外固定架关节牵张术治疗踝关节创伤性关节炎的临床疗效。 方法纳入2016年10月至2018年4月聊城市中医医院收治的早中期踝关节创伤性关节炎患者30例,排除非创伤性关节炎和终末期踝关节炎。其中接受单纯踝关节镜手术者纳入对照组(n=15),接受关节镜手术联合Ilizarov外固定架关节牵张成形术者纳入研究组(n=15),术后随访6个月,对比分析两组患者的治疗效果:疼痛视觉模拟评分(VAS)、踝关节功能评分(Kofoed评分)以及生活质量的变化。计数资料比较采用卡方或Fisher精确检验,计量资料比较采用独立样本t检验。 结果研究组治疗有效率大于对照组(χ2=7.214,P<0.05),术后疼痛视觉模拟评分明显低于对照组(t =10.342,P<0.05),Kofoed评分高于对照组(t =10.452,P<0.05);研究组生活质量显著高于对照组(P<0.05)。 结论关节镜手术联合关节牵张成形术对早中期踝关节创伤性关节炎较单纯关节镜手术短期效果更好,可成为临床治疗中的一种选择,但远期效果尚需进一步研究。  相似文献   
44.
目的应用6σ理论对肿瘤标志物项目的分析性能进行评价,并初步确定各项目的质量目标。 方法收集本实验室2018年1至12月室内质控数据和国家卫生健康委临床检验中心室间质量评价结果,以生物学变异导出的质量规范和国家室间质量评价标准作为允许总误差(TEa)计算6项肿瘤标志物的σ水平,并依据质量目标选择流程图和肿瘤标志物分析性能验证图评价肿瘤标志物的分析性能,进而为肿瘤标志物选择合适的质量目标。 结果应用不同层级的生物学变异导出的质量规范和国家室间质量评价标准,肿瘤标志物项目的σ水平存在显著差异;依据质量目标选择流程图:选择生物学变异导出的"适当的"质量规范作为CA125项目的质量目标,选择生物学变异导出的"最低的"质量规范作为t-PSA、CEA、AFP、CA199和CA153项目的质量目标。 结论6σ能够客观评价肿瘤标志物的分析性能,并为实验室质量目标的选择提供重要的参考价值。  相似文献   
45.
BackgroundThe third most common bariatric surgery is revisional bariatric surgery. The American College of Surgeons tracks outcomes using the Metabolic and Bariatric Surgery Accreditation Quality Initiative Program database. We used this database to examine trends in revisional bariatric surgery.ObjectiveTo evaluate how trends in bariatric revisional surgery have changed in recent years.SettingUniversity Hospital, United States.MethodsThe Metabolic and Bariatric Surgery Accreditation Quality Initiative Program database for 2015 to 2017 was examined for revisions of bariatric surgery. Patients who underwent revisional bariatric surgery were identified by the primary Current Procedural Terminology code, the REVCONV and PREVIOUS_SURGERY field as well as secondary Current Procedural Terminology codes. There is no exact code for sleeve gastrectomy (SG) to laparoscopic Roux-en-Y gastric bypass (LRYGB), so we used 43644 (GB)+REVCONV+PREVIOUS_SURGERY for this.ResultsFor the years 2015 to 2017 there were 57,683 revisions/conversions of 528,081 patients. The number of revisions increased over the study period by 5213 cases. The most common revision was laparoscopic adjustable gastric band (LAGB) to SG with 15,433 cases and the second was LAGB to LRYGB with 10,485 cases. There were 14,715 LAGB removals. It is more difficult to track SG to LRYGB but there were 8491 unlisted cases, which may have been sleeve to bypass.ConclusionLAGBs are being taken out or converted, and this group makes up the largest portion of revisions and conversions. It is difficult to track SG to LRYGB, but the number of unlisted cases continues to climb. This will likely surpass LAGB conversions with time. The Metabolic and Bariatric Surgery Accreditation Quality Initiative Program should be modified to capture revisions/conversions of SG.  相似文献   
46.
47.
目的观察认知行为干预在冠心病患者护理中的应用效果。方法选取本院2016年12月~2018年2月期间收治的53例冠心病患者,根据住院号奇偶性情况将其随机分为观察组(n=27)和对照组(n=26),对照组予以常规护理,观察组予以认知行为干预。比较两组患者控制态度评分、心理状况评分、生活质量改善情况及依从性。结果观察组控制态度评分、心理状况评分、生活质量改善情况及依从性与对照组比较,差异有统计学意义(P0.05)。结论在冠心病患者护理中给予认知行为干预应用效果极佳,可作为临床干预首选措施。  相似文献   
48.
49.
Using the SF-12 to measure physical and mental functioning, the authors examine the intra-individual changes in health-related quality of life (HRQOL) 6 months post-discharge for depressed older adults. In addition, they examine three sets of predictors that might influence these changes. The sample of depressed older adults was recruited from an inpatient geropsychiatry unit. Although their physical and mental health scores on the SF-12 were lower than comparable norms, the sample showed an average increase in their mental functioning but a decrease in the physical functioning over the 6 months. Negative life-events were significant predictors of people who reported no change in their mental health functioning and decreases in their physical health functioning. Interestingly, those who experienced positive life events were more likely to report declines and younger participants were more likely to report no change in their physical functioning. The findings indicate that the effects of depression on HRQOL can have enduring effects on a sample of previously hospitalized older adults. The significance of life event changes might signify the importance of taking into account non-traditional areas of medical interventions. Further, the findings indicate the usefulness of the SF-12 quantifying HRQOL outcomes.  相似文献   
50.
Preventing unintended pregnancies through access to modern family planning could avert 20-35% of maternal deaths, saving the lives of more than 100,000 women each year. Obstacles to wider access still exist, but they may be overcome by overt policy commitment to reproductive health services, partnership between stakeholders, community involvement and quality programs.  相似文献   
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