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   95022篇
  免费   8844篇
  国内免费   6144篇
耳鼻咽喉   908篇
儿科学   1151篇
妇产科学   900篇
基础医学   9143篇
口腔科学   1591篇
临床医学   12327篇
内科学   12390篇
皮肤病学   1507篇
神经病学   3897篇
特种医学   3505篇
外国民族医学   26篇
外科学   8322篇
综合类   19328篇
现状与发展   24篇
一般理论   4篇
预防医学   8195篇
眼科学   2055篇
药学   10993篇
  105篇
中国医学   7039篇
肿瘤学   6600篇
  2024年   390篇
  2023年   1203篇
  2022年   3024篇
  2021年   3808篇
  2020年   2945篇
  2019年   2646篇
  2018年   2633篇
  2017年   2854篇
  2016年   2698篇
  2015年   4239篇
  2014年   5254篇
  2013年   5413篇
  2012年   7995篇
  2011年   8407篇
  2010年   6551篇
  2009年   5762篇
  2008年   6214篇
  2007年   6180篇
  2006年   5785篇
  2005年   5146篇
  2004年   3779篇
  2003年   3571篇
  2002年   2981篇
  2001年   2288篇
  2000年   1823篇
  1999年   1382篇
  1998年   849篇
  1997年   836篇
  1996年   593篇
  1995年   493篇
  1994年   488篇
  1993年   295篇
  1992年   260篇
  1991年   239篇
  1990年   220篇
  1989年   153篇
  1988年   130篇
  1987年   118篇
  1986年   98篇
  1985年   61篇
  1984年   28篇
  1983年   14篇
  1982年   19篇
  1981年   24篇
  1980年   17篇
  1979年   19篇
  1978年   7篇
  1974年   10篇
  1973年   5篇
  1972年   9篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.
目的 :探讨三氧化二砷 (As2 O3 )对人肺癌细胞株 (Spc- A1)诱导凋亡的机制 ,为抗肿瘤药物的筛选和用药方式提供理论依据。方法 :体外培养 Spc- A1细胞株与不同浓度的 As2 O3 进行作用 ,应用 MTT比色法、流式细胞仪技术、电子显微镜技术观察细胞增殖率、细胞周期率、细胞凋亡率及亚细胞水平变化。结果 :As2 O3 能够抑制 Spc- A1细胞的增殖 ,且呈时间剂量依赖性 ,Spc- A1细胞凋亡率与药物浓度和时间呈依赖关系。电镜观察细胞线粒体肿胀、空泡 ,染色质浓缩、核碎裂。结论 :As2 O3 可诱导 Spc- A1细胞凋亡 ,细胞周期延长 ,线粒体变性。  相似文献   
92.
Ithasbeenconsideredbymodernmedicinethatbronchialasthmaisachronicairwayallergicinflammation(AAI)whichisthemajorfactorthatinducesreversibleairwayventilatingdisturbanceandbronchialhyper re sponsiveness(BHR)inasthmaticpatients,aswellasacorrelationbetweent…  相似文献   
93.
Tang  Xin  Chen  Lixin  Chen  Wenwen  Li  Peiyun  Zhang  Ling  Fu  Ping 《International urology and nephrology》2021,53(9):1911-1921
Purpose

Intradialytic hypotension (IDH) is a serious complication in dialysis patients. Diuretics might reduce the incidence of IDH by decreasing ultrafiltration. However, the effect of diuretics on IDH in maintenance dialysis patients is still unclear.

Methods

We searched Medline, Embase, the Cochrane Library, China National Knowledge Infrastructure and clinical trials registries from 1945 to May 2019. Randomized controlled trials (RCTs) or observational studies about IDH in maintenance dialysis with diuretics were included.

Results

Seven studies including 28,226 patients were included, of which 4 were RCTs involving mineralocorticoid receptor antagonists (MRAs) and 3 were observational studies involving loop diuretics. There was a trend that a lower incidence rate of IDH in maintenance dialysis patients who used loop diuretics than control, although the result was not statistically significant (OR 0.65, 95% CI 0.34–1.22, P?=?0.18). Similarly, lower incidence rate of all-cause mortality (OR 0.92, 95% CI 0.87–0.99; P?=?0.02) and cardiovascular (CV) mortality (OR 0.86, 95% CI 0.75–0.99, P?=?0.03) in dialysis patients who used loop diuretics than control. On the contrary, there were no significant difference in the incidence of IDH (OR 1.35, 95% CI 0.78–2.34, P?=?0.29) and all-cause mortality (OR 0.73, 95% CI 0.26–2.01; P?=?0.54) and CV mortality (OR 0.57, 95% CI 0.14–2.25; P?=?0.42) in maintenance dialysis patients who used MRAs compared with control.

Conclusion

Loop diuretics, but not MRAs, might have a potential benefit to reduce the incidence rate of IDH, all-cause mortality and CV mortality. More high-quality studies are needed to strengthen the arguments.

  相似文献   
94.
Wang  Ben  Deng  Yu-xuan  Yan  Sha  Xie  Hong-fu  Li  Ji  Jian  Dan 《Lasers in medical science》2021,36(3):649-655
Lasers in Medical Science - Acne scarring is one of the most common facial skin disorders. The appropriate treatments for acne scars in patients with rosacea have not been studied. This study was...  相似文献   
95.
96.
ObjectivesTo examine length of stay (LOS) and readmission rates for all minimally-invasive partial nephrectomy (MIPN) and MI radical nephrectomy (MIRN) performed for localized renal masses ≤7 cm in size (cT1RM) within 12 Michigan urology practices. Both RN and PN are commonly performed in treating cT1RM. Although technically more complex and associated with higher complication rates, Centers for Medicare & Medicaid Services considers MIPN an outpatient procedure and MIRN is inpatient.MethodsWe collected data for renal surgeries for cT1RM at MUSIC-KIDNEY practices between May 2017–February 2020. Data abstractors recorded clinical, radiographic, pathologic, surgical, and short-term follow-up data into the registry for cT1RM patients.ResultsWithin MUSIC-KIDNEY, 807 patients underwent MI renal surgery at 12 practices. Median LOS for cT1RM patients after MIPN (n = 531, 66%) was 2 days and after MIRN (n = 276, 34%) was also 2 days. Among patients undergoing laparoscopic or robotic PN, 171 (32%), 230 (43%), and 130 (24%) stayed ≤1, 2, ≥3 days. Among patients undergoing laparoscopic or robotic RN, 81 (29%), 112 (41%), and 83 (30%) stayed ≤1, 2, ≥3 days. No significant difference was observed between MIPN and MIRN on LOS commensurate with outpatient surgery (≤1-day, OR = 0.97, P = 0.87).ConclusionsLess than one-third of patients had a LOS ≤1-day and LOS was comparable for MIPN and MIRN. Centers for Medicare & Medicaid Services should be advised that MIPN is a more complex surgery than MIRN, most patients receiving a MIPN will require a ≥2-day hospital stay and it would be more appropriate to classify MIPN an inpatient procedure with MIRN.  相似文献   
97.
98.
99.
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