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   242441篇
  免费   20445篇
  国内免费   14403篇
耳鼻咽喉   2177篇
儿科学   3063篇
妇产科学   4879篇
基础医学   28343篇
口腔科学   4216篇
临床医学   30897篇
内科学   39884篇
皮肤病学   2820篇
神经病学   13544篇
特种医学   8705篇
外国民族医学   96篇
外科学   26672篇
综合类   34066篇
现状与发展   48篇
一般理论   45篇
预防医学   15098篇
眼科学   6681篇
药学   24230篇
  164篇
中国医学   10920篇
肿瘤学   20741篇
  2024年   709篇
  2023年   3491篇
  2022年   8679篇
  2021年   11424篇
  2020年   8391篇
  2019年   7592篇
  2018年   7992篇
  2017年   6967篇
  2016年   6662篇
  2015年   10087篇
  2014年   12689篇
  2013年   11888篇
  2012年   17531篇
  2011年   19214篇
  2010年   11723篇
  2009年   9382篇
  2008年   12760篇
  2007年   12818篇
  2006年   12366篇
  2005年   12449篇
  2004年   8603篇
  2003年   7639篇
  2002年   6607篇
  2001年   5995篇
  2000年   6110篇
  1999年   6410篇
  1998年   3678篇
  1997年   3712篇
  1996年   2813篇
  1995年   2608篇
  1994年   2248篇
  1993年   1507篇
  1992年   2292篇
  1991年   2003篇
  1990年   1674篇
  1989年   1473篇
  1988年   1288篇
  1987年   1192篇
  1986年   959篇
  1985年   769篇
  1984年   501篇
  1983年   389篇
  1982年   241篇
  1981年   208篇
  1980年   205篇
  1979年   249篇
  1978年   148篇
  1977年   120篇
  1976年   111篇
  1974年   116篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
谈耳鼻喉科教学中多媒体技术的应用   总被引:3,自引:0,他引:3  
多媒体教学技术应用于耳鼻喉科教学,具有直观性好、动态感强、信息量大等优点,能使教学信息直接、形象、具体、生动地展现给学生,让学生体会到学习的乐趣,是耳鼻喉科现代化教学的理想模式.  相似文献   
52.
In 1998, an epithermal neutron test beam was designed and constructed at the Tsing Hua Open-Pool Reactor (THOR) for the purpose of preliminary dosimetric experiments in boron neutron capture therapy (BNCT). A new epithermal neutron beam was designed at this facility, and is currently under construction, with clinical trials targeted in late 2004. Depth dose-rate distributions for the THOR BNCT test beam have been measured by means of activation foil and dual ion chamber techniques. Neutron and structure-induced gamma spectra measured at the test beam exit were configured into a source function for the Monte Carlo-based treatment planning code NCTPlan. Dose-rate scaling factors (DRSFs) were determined to normalize computationally derived dose-rate distributions with experimental measurements in corresponding mathematical and physical phantoms, and to thus enable accurate treatment planning using the NCTPlan code. A similar approach will be implemented in characterizing the new THOR epithermal beam in preparation for clinical studies. This paper reports the in-phantom calculated and experimental dosimetry comparisons and derived DRSFs obtained with the THOR test beam.  相似文献   
53.
关木通引起慢性间质性肾炎7例报告   总被引:3,自引:0,他引:3  
目的 观察关木通所致慢性肾损伤的临床和病理改变特点。方法 本组 7例中 ,男 5例 ,女 2例。 3例服关木通汤药 ,4例服含关木通成药。分析服用时间、累积总量与肾损害首发症状及症状出现时间、肾功能和肾病理改变的关系。结果 汤药组 :服药时间平均 3 3 3个月 ,累积总量平均 82 9 3 g ,首发症状为乏力 3例 ,夜尿增多 2例 ,平均时间为 8 3个月 ,Cr平均 40 2 μmol/L。肾病理 :3例均为重度寡细胞性肾间质纤维化 ,肾小管广泛萎缩。成药组 :服药时间平均 7 5个月 ,累积总量平均 13 6g ,乏力 3例 ,夜尿增多 1例 ,恶心呕吐、头痛头晕 1例 ,平均18 8个月 ,Cr 3 62 8μmol/L。肾病理为重度寡细胞性间质纤维化和灶状纤维化各 2例 ,肾小管灶状萎缩 3例 ,广泛萎缩 1例。结论 汤药组关木通积累大 ,发病时间早 ,肾病理改变重。提示关木通所致肾损其临床表现、病理改变与服用关木通时间、剂量相关。  相似文献   
54.
Bismuth subnitrate (BSN), a bismuth compound medically used for antidiarrheics, was orally administered to see whether it can reduce CDDP nephrotoxicity or not. Thirteen patients aged 19 approximately 60 with ovarian cancer entered this BSN-CDDP trial. A total of thirty three courses of BSN-CDDP treatment was undergone. BSN was administered orally at a dose of 50 mg/kg for five days before CDDP therapy. CDDP was infused for two hours. No vigorous hydration or diuresis was performed. Only 2,000 ml of saline with 20 mEq per liter of KCl was given for post-hydration. The median dose of CDDP was 100 mg/m2. The renal toxicity of BSN-CDDP treatment was minimum. 82% of the courses at the sixth day after the treatment had creatinine clearance levels which were more than 80% of those before the treatment. But twenty-four hour NAG and beta 2-microglobulin excretion were significantly increased. Bone marrow suppression and gastrointestinal disturbance were commonly observed. The results of our study indicate that BSN pretreatment reduces the renal toxicity of CDDP to some extent.  相似文献   
55.
56.
57.
Serum thyroxine concentrations were measured sequentially in eight healthy male volunteers after the oral administration of one of two brand name, commercially available thyroxine tablets. In all cases, levels peaked at 2 hours and did not return to baseline values until 24 hours after dosing. From 2 through 10 hours, statistically significant elevations in serum thyroxine concentrations were observed. Such fluctuations may be important in evaluating laboratory results in patients receiving replacement doses of thyroxine.  相似文献   
58.
The promoting effect of the Chinese medicinal herb, Wikstroemia chamaedaphne and Tung oil extracts (WC and HHPA) on carcinoma of uterine cervix induced by HSV-2 or MCA in mice was studied. The results showed that WC and HHPA extracts were not carcinogenic themselves. After carcinogen HSV-2 and MCA treatment, WC and HHPA were added separately. The inducing rates by HSV-2 increased from 7.4% to 21.1% and 26.3%, those by MCA increased from 56.5% to 82.8% and 84.4%. There was a significant difference between the combined groups and groups with HSV-2 or MCA only. The experimental results suggest that these two kinds of extracts play a promoting effect on carcinogenesis. The relation between the carcinogenesis of uterine cervix or nasopharynx and WC or HHPA extracts is discussed.  相似文献   
59.
60.
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