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   25045篇
  免费   2243篇
  国内免费   2104篇
耳鼻咽喉   170篇
儿科学   247篇
妇产科学   231篇
基础医学   2972篇
口腔科学   389篇
临床医学   3344篇
内科学   3573篇
皮肤病学   165篇
神经病学   1270篇
特种医学   860篇
外国民族医学   18篇
外科学   2892篇
综合类   4326篇
现状与发展   4篇
一般理论   1篇
预防医学   1752篇
眼科学   658篇
药学   2735篇
  24篇
中国医学   1382篇
肿瘤学   2379篇
  2024年   109篇
  2023年   408篇
  2022年   1040篇
  2021年   1215篇
  2020年   955篇
  2019年   833篇
  2018年   857篇
  2017年   745篇
  2016年   777篇
  2015年   1131篇
  2014年   1388篇
  2013年   1216篇
  2012年   1702篇
  2011年   1951篇
  2010年   1247篇
  2009年   997篇
  2008年   1306篇
  2007年   1364篇
  2006年   1274篇
  2005年   1312篇
  2004年   812篇
  2003年   913篇
  2002年   689篇
  2001年   575篇
  2000年   636篇
  1999年   743篇
  1998年   460篇
  1997年   461篇
  1996年   323篇
  1995年   302篇
  1994年   307篇
  1993年   169篇
  1992年   214篇
  1991年   179篇
  1990年   150篇
  1989年   150篇
  1988年   126篇
  1987年   103篇
  1986年   75篇
  1985年   82篇
  1984年   28篇
  1983年   17篇
  1982年   13篇
  1981年   11篇
  1980年   6篇
  1979年   19篇
  1974年   1篇
  1929年   1篇
排序方式: 共有10000条查询结果,搜索用时 13 毫秒
81.
[目的]探讨当归六黄汤加减对混合痔术后盗汗的疗效。[方法]对32例混合痔术后盗汗患者采用当归六黄汤加减。[结果]治愈11例(占34·4%),显效16例(占50·0%),有效5例(占16·6%)。[结论]当归六黄汤能有效治疗混合痔术后盗汗。  相似文献   
82.
83.
Axitinib is a potent vascular endothelial growth factor receptor (VEGFR) inhibitor, which has a strong inhibitory effect on the three isoforms of VEGFR 1–3. Having strong therapeutic efficacy, its broad use is limited by its side effects such as hypertension, proteinuria, cardiovascular damage, and liver and kidney dysfunction. Selenium compounds are broadly reported to have a good protective effect on cardiovascular disease, inflammation, infection, and immune function. In this study, a selenium substitute of axitinib was synthesized, and its anti-renal cell carcinoma activity and side effects were investigated. The results of the study indicated that Se-axitinib had potent antitumor activity on renal cell carcinoma (RCC), alleviated vascular hyperpermeability, and also alleviated axitinib-related side effects including hypertension, liver dysfunction and kidney dysfunction significantly. Therefore, we suggest that Se-axitinib could be a solution to the severe side effects of VEGFR inhibitors and provide evidence to improve the outcome of RCC treatment.

Se-axitinib is a selenium substitution of sulfur in axitinib, which reduced the side effect of VEGFR inhibitors and maintained the potent anticancer activity of the original drug.  相似文献   
84.
BackgroundThere is increasing attention on the association of socioeconomic status and individual behaviors (SES/IB) with mental health. However, the impacts of SES/IB on mental disorders are still unclear. To provide evidence for establishing feasible strategies on disease screening and prevention, we implemented Mendelian randomization (MR) design to appraise causality between SES/IB and mental disorders.MethodsWe conducted a two-sample MR study to assess the causal effects of SES and IB (dietary habits, habitual physical activity, smoking behaviors, drinking behaviors, sleeping behaviors, leisure sedentary behaviors, risky behaviors, and reproductive behaviors) on three mental disorders, including bipolar disorder, major depressive disorder and schizophrenia. A series of filtering steps were taken to select eligible genetic instruments robustly associated with each of the traits. Inverse variance weighted was used for primary analysis, with alternative MR methods including MR-Egger, weighted median, and weighted mode estimate. Complementary methods were further used to detect pleiotropic bias.ResultsAfter Bonferroni correction and rigorous quality control, we identified that SES (educational attainment), smoking behaviors (smoking initiation, number of cigarettes per day), risky behaviors (adventurousness, number of sexual partners, automobile speeding propensity) and reproductive behavior (age at first birth) were causally associated with at least one of the mental disorders.ConclusionsMR study provides robust evidence that SES/IB play broad impacts on mental disorders.  相似文献   
85.
The Epstein–Barr virus (EBV) can cause different types of cancer in human beings when the virus infects different cell types with various latent patterns. EBV shapes a distinct and immunosuppressive tumor microenvironment (TME) to its benefit by influencing and interacting with different components in the TME. Different EBV-associated malignancies adopt similar but slightly specific immunosuppressive mechanisms by encoding different EBV products to escape both innate and adaptive immune responses. Strategies reversing the immunosuppressive TME of EBV-associated malignancies have been under evaluation in clinical practice. As the interactions among EBV, tumor cells, and TME are intricate, in this review, we mainly discuss the epidemiology of EBV, the life cycle of EBV, the cellular and molecular composition of TME, and a landscape of different EBV-associated malignancies and immunotherapy by targeting the TME.  相似文献   
86.
87.
BackgroundOur previous study showed that two different regimens of moderate hypofractionated radiotherapy (HFRT) delivered with helical tomotherapy (HT) are well tolerated in older prostate cancer patients. We provide a longterm efficacy and toxicity after > 7 years of follow-up.Patients and methodsThe study recruited 33 patients from February 2009 to July 2011 (76 Gy/34F; Group-1); and 34 from July 2011 to February 2014 (71.6 Gy/28F; 50.4 Gy/25F for the risk of pelvic lymph nodes involvement (LNI) >15%; Group-2). The primary outcomes were biochemical failure (BF), biochemical failure and clinical disease failure (BCDF), progression-free survival (PFS), overall survival (OS), late genitourinary (GU) and gastrointestinal (GI) toxicity.ResultsThe average ages of two groups were 80 and 77 years and the proportions of patients with LNI > 15% were 69.7% and 73.5%, respectively. At the final follow-up in February 2020, 27.3% and 20.6% cases experienced BF, with a median time until BF of 3.3 years. A total of 38.8% patients reached primary endpoints, in which 18 deaths were reported BCDF events (45.5% vs. 32.4%, p = 0.271). There was no significant difference in 7-year PFS (68.6% vs. 74.8%, p = 0.591), BCDF (45.5% vs. 32.4%, p = 0.271) and OS (71.9% vs. 87.5%, p = 0.376) for full set analysis and for subgroup analysis (all p > 0.05). The incidence of grade ≥ 2 late GU (6.2% vs. 6.3%, p = 0.127) and GI toxicities (9.4% vs. 15.6%, p = 0.554) was comparable.ConclusionsIn older patients with localized prostate cancer, two moderate hypofractionated regimens were all well tolerated with similar, mild late toxicities and satisfactory survival, without necessity of prophylactic pelvic node irradiation.Key words: helical tomotherapy, radiation dose hypofractionation, progression-free survival, follow-up studies, prostatic neoplasms, adenocarcinoma  相似文献   
88.
89.
摘 要 目的: 研究松茸不同提取部位的体外抗肿瘤活性。 方法: 采用MTT法测定松茸乙醇提取物各部位及多糖部位对HepG-2细胞、Hela细胞和MCF-7细胞的抑制作用;采用流式细胞术检测多糖部位诱导HepG-2细胞和Hela细胞凋亡的作用。结果:松茸多糖部位体外对3种肿瘤细胞的IC50分别为53.77μg·ml-1(HepG-2)、40.04 μg·ml-1(Hela)、100.65 μg·ml-1(MCF-7),抑制作用均优于其他各部位,且对HepG-2细胞和Hela细胞抑制作用呈现良好的时间与浓度依赖性;松茸多糖部位能诱导HepG-2细胞和Hela细胞凋亡。结论: 松茸多糖部位能显著抑制HepG-2和Hela等肿瘤细胞的生长,具有诱导凋亡的作用,为松茸抗肿瘤的主要活性部位。  相似文献   
90.
中药饮片质量标准是中药炮制研究的重要内容,也是整个中药标准化体系的关键环节。尽管中药饮片有了国家标准,但是中药饮片标准化水平仍然处于较低水平。在中药饮片质量标准研究中,还存在一些实际问题需要我们加以重视和思考。本文结合作者长期的研究和生产实践,提出在中药饮片质量标准研究中要更加注重和传统炮制理论、炮制机理研究与药效物质研究的结合,努力构建更加全面、科学、合理的中药饮片质量标准。  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