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   203823篇
  免费   7707篇
  国内免费   2363篇
耳鼻咽喉   1941篇
儿科学   7093篇
妇产科学   3216篇
基础医学   22219篇
口腔科学   5707篇
临床医学   14647篇
内科学   37072篇
皮肤病学   3353篇
神经病学   13031篇
特种医学   4505篇
外国民族医学   4篇
外科学   29192篇
综合类   13589篇
现状与发展   5篇
一般理论   6篇
预防医学   16016篇
眼科学   3781篇
药学   20313篇
  33篇
中国医学   10246篇
肿瘤学   7924篇
  2023年   1449篇
  2022年   1770篇
  2021年   3998篇
  2020年   2789篇
  2019年   14230篇
  2018年   13891篇
  2017年   7019篇
  2016年   2417篇
  2015年   2293篇
  2014年   5412篇
  2013年   7211篇
  2012年   4976篇
  2011年   5113篇
  2010年   4176篇
  2009年   4089篇
  2008年   4808篇
  2007年   5986篇
  2006年   5997篇
  2005年   5578篇
  2004年   4429篇
  2003年   4438篇
  2002年   4058篇
  2001年   3983篇
  2000年   4022篇
  1999年   3614篇
  1998年   3500篇
  1997年   2897篇
  1996年   2631篇
  1995年   2996篇
  1994年   2767篇
  1993年   2176篇
  1992年   1764篇
  1991年   1735篇
  1990年   1454篇
  1989年   1175篇
  1988年   1201篇
  1987年   1128篇
  1985年   5506篇
  1984年   7366篇
  1983年   5883篇
  1982年   6313篇
  1981年   5764篇
  1980年   4957篇
  1979年   4989篇
  1978年   4089篇
  1977年   3073篇
  1976年   3540篇
  1975年   2747篇
  1974年   2526篇
  1973年   2235篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.
《Revue neurologique》2019,175(9):519-527
Background and purposeHospitals admitting acute strokes should offer access to mechanical thrombectomy (MT), but local organisations are still based on facilities available before MT was proven effective. MT rates and outcomes at population levels are needed to adapt organisations. We evaluated rates of MT and outcomes in inhabitants from the North-of-France (NoF) area.MethodWe prospectively evaluated rates of MT and outcomes of patients at 3 months, good outcomes being defined as a modified Rankin scale (mRS) 0 to 2 or like the pre-stroke mRS.ResultsDuring the study period (2016–2017), 666 patients underwent MT (454, 68.1% associated with intravenous thrombolysis [IVT]). Besides, 1595 other patients received IVT alone. The rate of MT was 81 (95% confidence interval [CI] 72–90) per million inhabitants-year, ranging from 36 to 108 between districts. The rate of IVT was 249 (95% CI 234–264) per million inhabitants-year, ranging from 155 to 268. After 3 months, 279 (41.9%) patients who underwent MT had good outcomes, and 167 (25.1%) had died. Patients living outside the district of Lille where the only MT centre is, were less likely to have good outcomes at 3 months, after adjustment on age, sex, baseline severity, and delay.ConclusionThe rate of MT is one of the highest reported up to now, even in low-rate districts, but outcomes were significantly worse in patients living outside the district of Lille, and this is not only explained by the delay.  相似文献   
92.
93.
94.
95.
96.
97.
98.

Background

Bone mineral density (BMD) has been found to improve after parathyroidectomy (PTX) in patients with primary hyperparathyroidism. There are few data on the effect of PTX on BMD in normocalcemic and normohormonal primary hyperparathyroidism.

Methods

A retrospective analysis of 92 primary hyperparathyroidism patients who underwent PTX between 2004 and 2012 with pre- and post-PTX dual-energy x-ray absorptiometry was performed. Within-person changes in BMD pre- and post-PTX were analyzed using log linear mixed models, stratified by biochemical status.

Results

Bone mineral density increased post-PTX in the whole cohort at the lumbar spine (+2.5%), femoral neck (+2.1%), and total hip (+1.9%) and decreased at the one-third radius (–0.9%). On comparison of BMD changes by profile, BMD increased in those with the typical profile at the lumbar spine (3.2%), femoral neck (2.9%), and total hip (2.9%) but declined at the one-third radius (–1.5%). In contrast, BMD improved only at the femoral neck (4.3%) in the normohormonal group and did not change at any site in the normocalcemic group. The typical group had a greater increase in BMD over time at the femoral neck and total hip compared with normocalcemic patients.

Conclusion

Our results indicate that the skeletal benefit of PTX was attenuated in normocalcemic and normohormonal patients, suggesting that skeletal changes after PTX may depend on biochemical profile.  相似文献   
99.
IntroductionInherited susceptibility to lung cancer risk in never-smokers is poorly understood. The major reason for this gap in knowledge is that this disease is relatively uncommon (except in Asians), making it difficult to assemble an adequate study sample. In this study we conducted a genome-wide association study on the largest, to date, set of European-descent never-smokers with lung cancer.MethodsWe conducted a two-phase (discovery and replication) genome-wide association study in never-smokers of European descent. We further augmented the sample by performing a meta-analysis with never-smokers from the recent OncoArray study, which resulted in a total of 3636 cases and 6295 controls. We also compare our findings with those in smokers with lung cancer.ResultsWe detected three genome-wide statistically significant single nucleotide polymorphisms rs31490 (odds ratio [OR]: 0.769, 95% confidence interval [CI]: 0.722–0.820; p value 5.31 × 10-16), rs380286 (OR: 0.770, 95% CI: 0.723–0.820; p value 4.32 × 10-16), and rs4975616 (OR: 0.778, 95% CI: 0.730–0.829; p value 1.04 × 10-14). All three mapped to Chromosome 5 CLPTM1L-TERT region, previously shown to be associated with lung cancer risk in smokers and in never-smoker Asian women, and risk of other cancers including breast, ovarian, colorectal, and prostate.ConclusionsWe found that genetic susceptibility to lung cancer in never-smokers is associated to genetic variants with pan-cancer risk effects. The comparison with smokers shows that top variants previously shown to be associated with lung cancer risk only confer risk in the presence of tobacco exposure, underscoring the importance of gene-environment interactions in the etiology of this disease.  相似文献   
100.
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