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   2489篇
  免费   280篇
  国内免费   135篇
耳鼻咽喉   3篇
儿科学   4篇
妇产科学   54篇
基础医学   48篇
口腔科学   6篇
临床医学   99篇
内科学   147篇
皮肤病学   18篇
神经病学   13篇
特种医学   13篇
外科学   62篇
综合类   548篇
预防医学   110篇
眼科学   10篇
药学   569篇
  5篇
中国医学   1177篇
肿瘤学   18篇
  2024年   5篇
  2023年   27篇
  2022年   54篇
  2021年   89篇
  2020年   95篇
  2019年   48篇
  2018年   60篇
  2017年   103篇
  2016年   115篇
  2015年   98篇
  2014年   278篇
  2013年   228篇
  2012年   247篇
  2011年   241篇
  2010年   190篇
  2009年   121篇
  2008年   123篇
  2007年   132篇
  2006年   127篇
  2005年   81篇
  2004年   84篇
  2003年   79篇
  2002年   59篇
  2001年   48篇
  2000年   37篇
  1999年   26篇
  1998年   22篇
  1997年   15篇
  1996年   11篇
  1995年   10篇
  1994年   11篇
  1993年   6篇
  1992年   7篇
  1991年   4篇
  1990年   4篇
  1989年   4篇
  1988年   3篇
  1987年   3篇
  1986年   2篇
  1985年   4篇
  1983年   1篇
  1979年   1篇
  1976年   1篇
排序方式: 共有2904条查询结果,搜索用时 31 毫秒
1.
2.
目的:观察柔肝消瘕饮对肝硬化大鼠肝组织病理形态学和血清、肝组织IL-1β、IL-6含量的影响。方法:采用复合因素造模法复制肝硬化大鼠模型,以复方鳖甲软肝片为对照,观察柔肝消瘢饮对肝硬化大鼠肝组织病理形态学、血清和肝组织IL-1β、IL-6含量的影响。结果:与正常组比较,模型组大鼠出现肝小叶损害,纤维组织增生,假小叶形成,血清IL-1β、IL-6含量和肝组织IL-6含量均明显升高(P〈0.01或P〈0.05);与模型组比较,各治疗组肝组织病理损害减轻,血清IL-1β和肝组织IL-6含量均有明显下降,差异有显著性意义(P〈0.01或P〈0.05);与对照组比较,高剂量组血清IL-6含量明显降低(P〈0.05)。结论:柔肝消瘢饮能显著下调肝硬化大鼠血清IL-1β、IL-6含量和肝组织IL-6含量,具有减轻肝硬化炎症损害,改善肝组织病理形态学作用。  相似文献   
3.
介绍一种能提高小丸微波干燥能力,避免小丸干燥开裂、过火等现象,可以提高小丸微波干燥均匀度的装置。  相似文献   
4.
目的:观察复方丹参滴丸对高粘滞血症血管内皮分泌功能的影响,探索其作用机制。方法:复合因素(高分子右旋糖酐、肾上腺素、牛血清白蛋白)、长时间(112天)造成高粘滞血症慢性模型;一次性静脉注射高分子右旋糖酐。皮下注射(sc)肾上腺素造成急性高粘滞血症模型,分别用复方丹参滴丸进行治疗,观察血管肉皮细胞分泌功能的变化。结果:慢性高粘滞血症模型血浆血栓素B2(TXB2)和内皮素(ET)浓度非常显升高,而6-酮-前列腺素F1x(6-酮)浓度非常显降低;急性高粘滞血症模型血管内皮分泌功能无显变化;长期使用复方丹参滴丸能调整、改善血管内皮分泌功能的异常状态;复方丹参滴丸改善血管内皮分泌功能的即时效应不显。  相似文献   
5.
肿瘤发病率逐年上升,治疗手段日渐丰富,肿瘤患者的生存期得到明显延长,生活质量得到显著提高。因此,肿瘤和放疗、化疗后引起的并发症对患者生活质量及疾病预后的影响显得愈加重要。癌性发热作为肿瘤患者的常见并发症之一受到密切关注。临床实践发现西医治疗非感染性发热效果欠佳,而中医药优势相对显著,退热效果明显,不易反复,对患者生活质量及预后改善有利。  相似文献   
6.
Many women find the idea of a once-a-month contraceptive pill an attractive concept. Mifepristone has been shown to be effective as a contraceptive if administered in the early luteal phase. We tested the contraceptive efficacy of 200 mg of mifepristone on day luteinizing hormone (LH) + 2 in a group of 32 women who used a fertility monitor to identify the LH surge. We also recruited a control group, comprising 20 women who were trying to conceive. In this group, 12 women conceived during a total of 50 control cycles (probability of pregnancy 0.25-0.32). Women in the treatment group contributed to a total of 178 cycles and there were two pregnancies (probability of pregnancy 0.01). An LH surge was not detected in 34 cycles (19.1%). In 20 cycles (11.2%) this was due to imperfect use while 14 were monitor method failures (7.9%). Treatment with mifepristone in the early luteal phase did not disrupt the cycle length but women reported slight vaginal bleeding in 15% of the cycles. The combination of a home-use fertility monitor with once-a-month administration of mifepristone (especially if mifepristone is administered at the early luteal phase) is an acceptable contraceptive option with minimal side effects. Unfortunately, it is difficult to envisage how an easier way of defining the correct timing, which required less compliance, could be devised.  相似文献   
7.
目的:观察五淋丸对异丙肾上腺素(Iso)诱发的大鼠心肌缺血的保护作用。方法:采用腹腔注射诱导大鼠致急性心肌缺血的动物模型。实验大鼠随机分为Iso模型组,阳性对照组和五淋丸大、中、小剂量组,观察各组大鼠心电图ST-iunction(J点)的位移、血清酶及血流动力学变化。结果:五淋丸大、中、小剂量组大鼠心电图J点的位移明显低于模型组(P〈O.05或P〈0.01);血清肌酸激酶((K)及乳酸脱氢酶(LDH)活性低于模型组(P〈O.01);血流动力学指标:左心室收缩压(LVSP)、左心室舒张末压(LVEDP)、左心室等容期压力最大变化速率(土dp/dtmax)显著高于模型组(P〈O.05或P〈0.01)。结论:五淋丸对异丙肾上腺素所致大鼠缺血心肌具有保护作用,其机制可能与其改善心肌缺血大鼠心脏的舒缩功能有关。  相似文献   
8.
华佗再造丸抗血栓作用及对实验性微循环障碍的影响   总被引:5,自引:0,他引:5  
目的 观察华佗再造丸对血瘀证动物模型体内血栓,体外血栓的作用及对实验性微循环障碍的影响。方法 实验体国栓采用Chandel法,体内血栓采用动物颈动脉电流刺激法,高分子右旋糖酐造成动物循环障碍。结果 华佗再造丸具有抑制体外全形成、延长体内血栓作用并能降低动物的血液粘度、抑制血小板聚集性,改善动物脑供血供和软脑膜微循环障碍的功能。结论 华佗再造丸具有活血化瘀、拮抗血栓形成的功效,是治疗脑血栓后遗症的  相似文献   
9.
The warning issued by the UK Committee on Safety Medicines in October 1995, followed by their 'Dear Doctor' letter of October 18, 1995, that oral contraceptive pills containing gestodene or desogestrel were associated with a higher risk of venous thromboembolism has had a negative impact on public heath. A significant number of women either switched brands or ceased contraception altogether following the announcement. National data suggest a strong association between the pill scare and a substantial increase in the number of unintended pregnancies, particularly significant among younger women, with use of oral contraception falling from 40 to 27% of under 16s between 1995-1996 and 1996-1997. The resulting cost of the increase in births and abortions to the National Health Service has been estimated at about Pound Sterling 21 million for maternity care and from Pound Sterling 46 million for abortion provision. The level of risk should, in future, be more carefully assessed and advice more carefully presented in the interests of public health.  相似文献   
10.
The relatively short history of hormonal contraception has been marked by a series of 'pill scares', all of which--after creating panic among users--were proven to be unfounded in terms of public health impact. The latest pill scare, provoked by regulatory action in the United Kingdom and the Federal Republic of Germany in response to the publication of a series of articles indicating a doubling of risk of deep venous thrombosis in users of oral contraceptives containing third-generation progestins, seems finally settled: both the British and the German Drug Regulatory Authorities have now reverted their verdict. The damage unfortunately stays: hundreds of thousands of women have been compelled to abandon the pill of their choice, often deciding to drop contraception altogether, thereby exposing themselves to unwanted pregnancy and--in a number of cases--to pregnancy termination. This latest episode should be turned into something positive: we need to learn that, in the case of drugs in widespread use, before restrictive action is taken--and except for very rare and specific instances--the scientific community must carry out an exhaustive debate on the reality and importance of the observed effects. Although the public should, in each instance, be properly informed, it is only after this process has been completed that restrictive action should be taken. It is hoped that, after this last episode, all concerned have learned this simple principle and will accept being guided by it from now on.  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