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   126980篇
  免费   7213篇
  国内免费   1169篇
耳鼻咽喉   1951篇
儿科学   1914篇
妇产科学   1873篇
基础医学   20232篇
口腔科学   3076篇
临床医学   11823篇
内科学   22716篇
皮肤病学   3966篇
神经病学   10304篇
特种医学   7257篇
外科学   16625篇
综合类   551篇
现状与发展   3篇
一般理论   27篇
预防医学   6691篇
眼科学   3197篇
药学   11457篇
中国医学   1457篇
肿瘤学   10242篇
  2023年   906篇
  2022年   2715篇
  2021年   4393篇
  2020年   2105篇
  2019年   2945篇
  2018年   3675篇
  2017年   2990篇
  2016年   3901篇
  2015年   5434篇
  2014年   6440篇
  2013年   7504篇
  2012年   11240篇
  2011年   10778篇
  2010年   6170篇
  2009年   5291篇
  2008年   7530篇
  2007年   7200篇
  2006年   6475篇
  2005年   5995篇
  2004年   5214篇
  2003年   4538篇
  2002年   3904篇
  2001年   3039篇
  2000年   2789篇
  1999年   2141篇
  1998年   908篇
  1997年   679篇
  1996年   517篇
  1995年   458篇
  1994年   393篇
  1993年   338篇
  1992年   750篇
  1991年   700篇
  1990年   643篇
  1989年   559篇
  1988年   469篇
  1987年   466篇
  1986年   332篇
  1985年   369篇
  1984年   261篇
  1983年   191篇
  1982年   132篇
  1981年   168篇
  1980年   129篇
  1979年   222篇
  1978年   163篇
  1976年   132篇
  1975年   120篇
  1974年   139篇
  1973年   119篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
针灸治疗中风偏瘫选穴规律研究   总被引:2,自引:1,他引:2  
目的对针灸治疗中风偏瘫的临床研究文献进行统计分析,为临床选穴与合理组穴提供依据。方法收集近28年来针灸治疗中风偏瘫的临床文献,对选用的腧穴种类、归经及使用频次进行统计分析。结果针灸治疗弛缓性偏瘫为主的文献276篇,共使用195个穴位,总频次为2 957次,十四经穴174个,总频次2 849次,占96%;经外奇穴108次,占4%。出现频率占10%以上的经穴29个,阳经穴21个,阴经穴8个。针灸治疗痉挛性偏瘫为主的文献52篇,共使用106穴,总频次为530次,十四经穴97个,总频次511次,占96%;经外奇穴19次,占4%。出现频率占10%以上的经穴31个,阳经穴21个,阴经穴10个。治疗弛缓性偏瘫和痉挛性偏瘫,均以十四经穴为主体,选用阳经穴为主。结论针灸治疗中风弛缓性瘫选用手足阳明、足少阳经、督脉四条阳经,治疗痉挛性瘫以手足少阳经、手阳明经及足太阳经四条经脉为主,上肢配以心包经,下肢配以足太阴经和足阳明经。  相似文献   
992.

Ethnopharmacological relevance

Uwhangchungsimwon (UCW) is a representative traditional herbal medicine for central nervous system disorders in East Asia countries over thousand years. To evaluate the pharmacological effects of UCW against oxidative brain injury in a chronic restraint stress mice model.

Methods and materials

C57BL/6 male mice underwent daily oral administration of distilled water, UCW or ascorbic acid 1 h before induction of restraint stress (5 h of immobilization daily for 14 days). Nitric oxide (NO), total reactive oxygen species (ROS) levels, malondialdehyde, protein carbonyl contents, and activities of antioxidant enzymes, and concentrations of corticosterone, adrenaline, noradrenaline, and dopamine, were measured in brain tissues or sera.

Results

Restraint stress notably increased NO and ROS levels, malondialdehyde and protein carbonyl contents in brain tissues, but decreased activities of catalase, glutathione reductase and glutathione peroxidase. These alterations were significantly ameliorated by UCW. UCW significantly attenuated the elevated serum concentrations of corticosterone, adrenaline and noradrenaline. UCW also significantly normalized the gene expressions in brain tissues altered by restraint stress; up-regulation of phenylethanolamine N-methyltransferase (PNMT) and N-methyl-d-aspartate type 1 receptor (NMDAR1), and down-regulation of gamma-Aminobutyric acid type A receptor (GABAAR), glutamate decarboxylase 1 (GAD 67), and glutamate decarboxylase 2 (GAD 65), respectively. Moreover, UCW considerably restored neurogenesis in the hippocampal regions which was disturbed by chronic restraint stress.

Conclusions

These results evidenced that UCW has pharmacological properties for brain protection and neurogenesis in status of stress-associated oxidative damage, and the underlying mechanisms involve the regulation of HPA axis in stress responses.  相似文献   
993.
We examined the effect of HemoHIM on the protective efficacy of hematopoietic stem cells and on the recovery of immune cells against sublethal doses of ionizing radiation. Two‐month‐old mice were exposed to γ‐rays at a dose of 8, 6.5, or 5 Gy for a30‐day survival study, endogenous spleen colony formation, or other experiments, respectively. HemoHIM was injected intraperitoneally before and after irradiation. Our results showed that HemoHIM significantly decreased the mortality of sublethally irradiated mice. The HemoHIM administration decreased the apoptosis of bone marrow cells in irradiated mice. On the other hand, HemoHIM increased the formation of endogenous spleen colony in irradiated mice. In irradiated mice, the recovery of total leukocytes in the peripheral blood and lymphocytes in the spleen were enhanced significantly by HemoHIM. Moreover, the function of B cells, T cells, and NK cells regenerated in irradiated mice were significantly improved by the administration of HemoHIM. HemoHIM showed an ideal radioprotector for protecting hematopoietic stem cells and for accelerating the recovery of immune cells. We propose HemoHIM as a beneficial supplement drug during radiotherapy to alleviate adverse radiation‐induced effects for cancer patients. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
994.
The oncogenic PI3K/Akt/mammalian target of rapamycin (mTOR) signaling axis and its downstream effector, the ribosomal protein S6 kinase 1 (S6K1) play a key role in mediating cell survival in various tumor cells. Here, we investigated the effects of brassinin (BSN), a phytoalexin first identified as a constituent of cabbage, on the PI3K/Akt/mTOR/S6K1 activation, cellular proliferation, and apoptosis in PC‐3 human prostate cancer. BSN exerted a significant dose‐dependent cytotoxicity and reduced constitutive phosphorylation of Akt against androgen‐independent PC‐3 cells as compared to androgen‐dependent LNCaP cells. Moreover, knockdown of androgen receptor (AR) by small interfering RNA enhanced the potential effect of BSN on induction of apoptosis in LNCaP cells. BSN clearly suppressed the constitutive activation of PI3K/Akt/mTOR/S6K1 signaling cascade, which correlated with the induction of apoptosis as characterized by accumulation of cells in subG1 phase, positive Annexin V binding, TUNEL staining, loss of mitochondrial membrane potential, down‐regulation of antiapoptotic and proliferative proteins, activation of caspase‐3, and cleavage of PARP. Additionally, BSN could block broad‐spectrum inhibition of PI3K/Akt/mTOR/S6K1 axes, and aberrant Akt activation by pcDNA3‐myr‐HA‐Akt1 plasmid could not prevent the observed suppressive effect of BSN on constitutive mTOR activation. Finally, overexpression of Bcl‐2 also attenuated BSN‐mediated apoptosis in PC‐3 cells. Taken together, our findings suggest that BSN can interfere with multiple signaling cascades involved in tumorigenesis and might be provided as a potential therapeutic candidate for both the prevention and treatment of prostate cancer. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
995.
996.
997.
998.

Background.

Both the American Society of Clinical Oncology and the European Society for Medical Oncology strongly endorse integrating oncology and palliative care (PC); however, a global consensus on what constitutes integration is currently lacking. To better understand what integration entails, we conducted a systematic review to identify articles addressing the clinical, educational, research, and administrative indicators of integration.

Materials and Methods.

We searched Ovid MEDLINE and Ovid EMBase between 1948 and 2013. Two researchers independently reviewed each citation for inclusion and extracted the indicators related to integration. The inter-rater agreement was high (κ = 0.96, p < .001).

Results.

Of the 431 publications in our initial search, 101 were included. A majority were review articles (58%) published in oncology journals (59%) and in or after 2010 (64%, p < .001). A total of 55 articles (54%), 33 articles (32%), 24 articles (24%), and 14 articles (14%) discussed the role of outpatient clinics, community-based care, PC units, and inpatient consultation teams in integration, respectively. Process indicators of integration include interdisciplinary PC teams (n = 72), simultaneous care approach (n = 71), routine symptom screening (n = 25), PC guidelines (n = 33), care pathways (n = 11), and combined tumor boards (n = 10). A total of 66 articles (65%) mentioned early involvement of PC, 18 (18%) provided a specific timing, and 28 (28%) discussed referral criteria. A total of 45 articles (45%), 20 articles (20%), and 66 articles (65%) discussed 8, 4, and 9 indicators related to the educational, research, and administrative aspects of integration, respectively.

Conclusion.

Integration was a heterogeneously defined concept. Our systematic review highlighted 38 clinical, educational, research, and administrative indicators. With further refinement, these indicators may facilitate assessment of the level of integration of oncology and PC.  相似文献   
999.
Masson's vegetant intravascular hemangioendothelioma has only been reported intracranially in 12 patients. The pathological diagnosis is important given its benign natural history. We report the 13th case in a woman who presented with headaches and dysphasia. A thorough literature review is presented and an appropriate management strategy is proposed.  相似文献   
1000.
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