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   52248篇
  免费   4857篇
  国内免费   2845篇
耳鼻咽喉   451篇
儿科学   739篇
妇产科学   788篇
基础医学   7437篇
口腔科学   1163篇
临床医学   5710篇
内科学   8728篇
皮肤病学   775篇
神经病学   3906篇
特种医学   1987篇
外国民族医学   15篇
外科学   6137篇
综合类   6035篇
现状与发展   5篇
一般理论   9篇
预防医学   3311篇
眼科学   1329篇
药学   5368篇
  29篇
中国医学   1899篇
肿瘤学   4129篇
  2023年   443篇
  2022年   1027篇
  2021年   1616篇
  2020年   1200篇
  2019年   1113篇
  2018年   1405篇
  2017年   1283篇
  2016年   1232篇
  2015年   1675篇
  2014年   2099篇
  2013年   2125篇
  2012年   2928篇
  2011年   3226篇
  2010年   2005篇
  2009年   1699篇
  2008年   2360篇
  2007年   2432篇
  2006年   2302篇
  2005年   2139篇
  2004年   1618篇
  2003年   1522篇
  2002年   1250篇
  2001年   2752篇
  2000年   2681篇
  1999年   2315篇
  1998年   977篇
  1997年   771篇
  1996年   561篇
  1995年   518篇
  1994年   444篇
  1993年   343篇
  1992年   1128篇
  1991年   976篇
  1990年   884篇
  1989年   950篇
  1988年   862篇
  1987年   789篇
  1986年   738篇
  1985年   628篇
  1984年   390篇
  1983年   326篇
  1982年   187篇
  1981年   143篇
  1980年   119篇
  1979年   206篇
  1973年   93篇
  1972年   92篇
  1971年   94篇
  1970年   83篇
  1968年   83篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.

Background  

Bortezomib, a proteasome-specific inhibitor, has emerged as a promising cancer therapeutic agent. However, development of resistance to bortezomib may pose a challenge to effective anticancer therapy. Therefore, characterization of cellular mechanisms involved in bortezomib resistance and development of effective strategies to overcome this resistance represent important steps in the advancement of bortezomib-mediated cancer therapy.  相似文献   
52.
OBJECTIVE: The C2A domain of Synaptotagmin I is a molecular probe for the specific imaging of cell death. Here we test the hypothesis that the uptake of 99mTc-C2A in the acute phase of an infarction is associated with cardiac dysfunction in follow-ups. METHODS: The left coronary artery was occluded in Sprague-Dawley rats for 0, 10, 20, and 30 min. 99mTc-C2A was injected intravenously at 2 h of reperfusion. Anterior planar images were acquired with one million counts on a gamma camera 3 h after injection. 99mTc-C2A uptake was calculated as the total counts in the left ventricle region minus blood pool signal. The in-vivo signal detected was correlated with wall motion score index at 1 and 3 weeks follow-ups measured by echocardiography. RESULTS: 99mTc-C2A uptake was higher with increased ischemic time (2244+/-852, 4054+/-1223, and 6178+/-1451 for 10, 20, and 30 min ischemia, analysis of variance P<0.001). A significant correlation was found between 99mTc-C2A uptake and wall motion score index at 1 week (R=0.800, P=0.0006) and 3 weeks (R=0.810, P=0.0008). CONCLUSION: In this ischemia/reperfusion model, 99mTc-C2A uptake in the acute phase was associated with functional abnormality at 1 and 3 weeks. This demonstrates the potential diagnostic and prognostic value of 99mTc-C2A as a novel imaging agent.  相似文献   
53.
54.
Direct vascular injury after primary total knee arthroplasty is rare. This case report illustrates a 65-year-old female who was diagnosed with a pseudoaneurysm of the popliteal artery when she was investigated for increased leg swelling and pain 1 week after total knee arthroplasty. She had a percutaneous endovascular repair with a stent after thrombectomy.  相似文献   
55.
56.
Degranulating mast cells are increased in the airway smooth muscle (ASM) of asthmatics, where they may influence ASM function. The aim of the present study was to determine whether histamine and tryptase modulate ASM cell granulocyte-macrophage colony-stimulating factor (GM-CSF) and RANTES (regulated on activation, normal T-cell expressed and secreted) release and also to examine which receptors are involved in this release. Confluent, quiescent ASM cells from asthmatic and nonasthmatic donors were treated with histamine (1 microM-100 microM) with and without histamine receptor antagonist pre-treatment, or the protease-activated receptor (PAR)-2 agonists tryptase (0.5-5 nM) and SLIGKV (100 and 400 microM). The cells were then stimulated with interleukin (IL)-1beta and/or tumour necrosis factor (TNF)-alpha (10 ng.mL(-1)) or left unstimulated for 24 h. Release of GM-CSF and RANTES was determined by ELISA and prostaglandin (PG)E(2) measured by enzyme immunoassay. Neither histamine nor tryptase induced ASM GM-CSF or RANTES secretion. However, histamine increased IL-1beta-induced GM-CSF release and markedly reduced TNF-alpha-induced RANTES release by both asthmatic and nonasthmatic cells to a similar extent, but did not modulate PGE(2) release. All changes involved activation of the histamine H1 receptor as they were partially or fully blocked by chlorpheniramine, but not ranitidine. Tryptase, via its proteolytic activity, also potentiated GM-CSF, but not RANTES, release from asthmatic and nonasthmatic ASM cells induced by both cytokines. PAR-2 involvement in the tryptase potentiation was unlikely because SLIGKV had no effect. In conclusion, mast cells, through histamine and tryptase, may locally modulate airway smooth muscle-induced inflammation in asthma.  相似文献   
57.
目的 探讨护理干预在2型糖尿病患康复中的作用。方法 对80例2型糖尿病患,随机分成干预组和对照组,干预组实施全程护理干预,对照组实施常规的治疗护理。结果 干预组血糖控制良好,并发症发生率明显降低。结论 护理干预是2型糖尿病康复治疗的有效方法。  相似文献   
58.
59.
60.
目的探讨利用球囊导管加压注射泛影葡胺行子宫输卵管造影的应用价值。方法对219例不孕症用76%泛影葡胺采用球囊导管加压注射法作子宫输卵管造影检查,并在透视下实时点片。结果普通注射时双侧输卵管显示185例(84.47%),单侧显示24例;加压注射后203例(92.69%)双侧输卵管显示,单侧显示14例,成功率100%。子宫畸形见于9例,输卵管异常131例,造影剂弥散与吸收异常104例。结论利用球囊导管加压注射水溶性造影剂,可以明显提高子宫输卵管造影质量及输卵管再通效果,有重要的临床价值。  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