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   7296篇
  免费   444篇
  国内免费   99篇
耳鼻咽喉   89篇
儿科学   114篇
妇产科学   141篇
基础医学   813篇
口腔科学   268篇
临床医学   600篇
内科学   2253篇
皮肤病学   85篇
神经病学   619篇
特种医学   257篇
外国民族医学   2篇
外科学   1207篇
综合类   14篇
一般理论   1篇
预防医学   287篇
眼科学   77篇
药学   364篇
中国医学   6篇
肿瘤学   642篇
  2024年   15篇
  2023年   137篇
  2022年   265篇
  2021年   481篇
  2020年   278篇
  2019年   321篇
  2018年   356篇
  2017年   247篇
  2016年   286篇
  2015年   304篇
  2014年   403篇
  2013年   436篇
  2012年   629篇
  2011年   544篇
  2010年   306篇
  2009年   296篇
  2008年   415篇
  2007年   375篇
  2006年   343篇
  2005年   270篇
  2004年   215篇
  2003年   185篇
  2002年   147篇
  2001年   50篇
  2000年   47篇
  1999年   40篇
  1998年   37篇
  1997年   20篇
  1996年   23篇
  1995年   21篇
  1994年   18篇
  1993年   8篇
  1992年   21篇
  1991年   28篇
  1990年   32篇
  1989年   28篇
  1988年   19篇
  1987年   22篇
  1986年   18篇
  1985年   16篇
  1984年   9篇
  1980年   8篇
  1979年   15篇
  1978年   11篇
  1977年   8篇
  1974年   14篇
  1971年   8篇
  1970年   10篇
  1969年   8篇
  1966年   7篇
排序方式: 共有7839条查询结果,搜索用时 15 毫秒
121.
122.
In this article we analyze some of the structural characteristics of the coding section and the intron of the human chemokine CXC receptor 4 (a 7-transmembrane receptor) pre-mRNA. In the coding sequence the frequencies of the individual nucleotides do not depart significantly from 0.25, while in the intron the frequencies of the As and Gs are significantly lower and higher, respectively, than expected from a random distribution. Analysis of the pattern of association of nucleotides into triplets or couples shows that some triplets or couples occur with frequencies significantly higher or lower than expected when assuming a random association of nucleotides. In particular, in the intron combinations of the same nucleotide are over-represented. 7-or-more nucleotide repeats occur in both the coding section and the intron with frequencies which exceed the confidence limits for a random distribution. For the coding sequence this is possibly explained by the alternans of relatively similar hydrophobic-coding sections and relatively similar intervening intracellular and extracellular hydrophilic-coding sections. 7-or-more nucleotide repeats in reverse order and in reverse/complemented order occur in the intron, but not in the coding section, with frequencies which significantly exceed a random distribution. The numerous intronic repeats in reverse/complemented order may be of relevance for the secondary structure of the intron and might be one important element of the integrated splicing code.  相似文献   
123.
European Child & Adolescent Psychiatry - Attention-Deficit/Hyperactivity Disorder (ADHD) comprises disturbances in attention, emotional regulation, and reward-related processes. In spite of the...  相似文献   
124.
125.
126.
Tumor progression is deeply influenced by epigenetic changes induced by tumor stroma. Cancer-associated fibroblasts (CAFs) have been reported to promote epithelial–mesenchymal transition in cancer cells, thereby enhancing their aggressiveness and stem-like properties. As CAFs are able to recruit endothelial progenitor cells (EPCs) to tumor site, we aim to investigate their interplay for prostate carcinoma progression. Both prostate CAFs and cancer cells actively recruit EPCs, known to affect tumor progression through increased vasculogenesis. EPCs synergize with CAFs to further promote epigenetic plasticity of cancer cells, through a mesenchymal-to-amoeboid transition. Indeed, after fibroblasts have engaged epithelial–mesenchymal transition in cancer cells, a further shift towards amoeboid motility is promoted by EPCs through contact-mediated triggering of the bidirectional ephrinA1/EphA2 signaling. The activation of ephrinA1 reverse pathway enhances EPC-induced neo-vascularization, thus promoting tumor growth, while EphA2 forward signaling elicits mesenchymal–amoeboid transition in cancer cells, favoring their adhesion to endothelium, transendothelial migration, and lung metastatic colonization. We therefore underscore that the metastatic advantage given by tumor microenvironment embraces different motility strategies and propose EphA2-targeted tools as useful adjuvants in anti-metastatic treatments.  相似文献   
127.
Anxiety and depression in Parkinson’s disease (PD) reduce well-being of the patients. Emotional alterations influence motor skills and cognitive performance; moreover, they contribute significantly and independently to worsen rehabilitative treatment response. We investigated anxiety, depression, and quality of life in PD patients subjected to multidisciplinary rehabilitative training. The self-controlled study included 100 PD patients (49 males and 51 females with the mean age of 64.66 years) admitted to 60 days hospitalization rehabilitative program, between January 2017 and December 2018. Motor, cognitive, linguistic abilities, and functional independence were evaluated at admission (T0 baseline visit) and 60 days after (T1) the multidisciplinary rehabilitation including motor exercises, speech therapies, and cognitive intervention. The multidisciplinary rehabilitation improved functional status in PD patients and exerted its positive effects on mood, motor abilities, autonomy in the activities of daily life, perception of quality of life, cognitive performance and speech skills. Non-motor symptoms may worsen severe disability and reduce quality of life. They are often poorly recognized and inadequately treated. Nonetheless, multidisciplinary rehabilitative training represents an optimal strategy to improve disease management. The study was approved by Istituito di Ricovero e Cura a Carattere Scientifico (IRCCS) Centro Neurolesi “Bonino-Pulejo” Ethical Committee (approval No. 6/2016) in June 2016.  相似文献   
128.
129.
The phenotype of infused cells is a major determinant of Adoptive T-cell therapy (ACT) efficacy. Yet, the difficulty in deciphering multiparametric cytometry data limited the fine characterization of cellular products. To allow the analysis of dynamic and complex flow cytometry samples, we developed cytoChain, a novel dataset mining tool and a new analytical workflow. CytoChain was challenged to compare state-of-the-art and innovative culture conditions to generate stem-like memory cells (TSCM) suitable for ACT. Noticeably, the combination of IL-7/15 and superoxides scavenging sustained the emergence of a previously unidentified nonexhausted Fit-TSCM signature, overlooked by manual gating and endowed with superior expansion potential. CytoChain proficiently traced back this population in independent datasets, and in T-cell receptor engineered lymphocytes. CytoChain flexibility and function were then further validated on a published dataset from circulating T cells in COVID-19 patients. Collectively, our results support the use of cytoChain to identify novel, functionally critical immunophenotypes for ACT and patients immunomonitoring.  相似文献   
130.
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