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   7662篇
  免费   711篇
  国内免费   435篇
耳鼻咽喉   25篇
儿科学   89篇
妇产科学   86篇
基础医学   631篇
口腔科学   121篇
临床医学   687篇
内科学   1279篇
皮肤病学   127篇
神经病学   372篇
特种医学   282篇
外国民族医学   1篇
外科学   499篇
综合类   1035篇
现状与发展   1篇
预防医学   467篇
眼科学   74篇
药学   1838篇
  8篇
中国医学   976篇
肿瘤学   210篇
  2024年   52篇
  2023年   165篇
  2022年   244篇
  2021年   379篇
  2020年   292篇
  2019年   321篇
  2018年   304篇
  2017年   299篇
  2016年   317篇
  2015年   374篇
  2014年   493篇
  2013年   709篇
  2012年   551篇
  2011年   518篇
  2010年   404篇
  2009年   352篇
  2008年   330篇
  2007年   268篇
  2006年   323篇
  2005年   265篇
  2004年   197篇
  2003年   178篇
  2002年   157篇
  2001年   110篇
  2000年   92篇
  1999年   82篇
  1998年   83篇
  1997年   71篇
  1996年   61篇
  1995年   96篇
  1994年   74篇
  1993年   61篇
  1992年   61篇
  1991年   52篇
  1990年   58篇
  1989年   43篇
  1988年   32篇
  1987年   35篇
  1986年   49篇
  1985年   31篇
  1984年   44篇
  1983年   29篇
  1982年   31篇
  1981年   33篇
  1980年   23篇
  1979年   16篇
  1978年   15篇
  1977年   12篇
  1976年   8篇
  1975年   5篇
排序方式: 共有8808条查询结果,搜索用时 62 毫秒
1.
2.
3.
4.
Objectives: To examine the factors associated with increase in lumbar spine bone mineral density (LS-BMD) by bisphosphonates (BPs) with active vitamin D analog (aVD).

Methods: Two independent postmenopausal osteoporotic patients treated by BPs with aVD for 24 months (Study 1: n?=?93, Study 2: n?=?99) were retrospectively analyzed.

Results: In Study 1, LS-BMD of the patients significantly increased for 24 m (5.4%, p?r2: 0.088, p?=?.02). While average sCa of the patients was 9.2?mg/dL before treatment, it increased time-dependently to 9.6?mg/dL for 24 m by treatment. As each patient had their LS-BMD five times during the study, there were four instances of %LS-BMD in each patient, resulting in 372 instances of %LS-BMD in Study 1. The smallest Akaike’s information criterion value for the most appropriate cut-off levels of sCa for %LS-BMD by treatment every 6 m was 9.3?mg/dL. The %LS-BMD by treatment for 6 m during 24 m period in patients with sCa ≥9.3?mg/dL (1.5%) was significantly higher than that in patients with sCa <9.3?mg/dL (0.8%, p?=?.038). The results of Study 2 were similar to those of Study 1, confirming the phenomena observed.

Conclusion: sCa was associated with an increased LS-BMD by BPs with aVD.  相似文献   
5.
6.
Metastatic melanoma is the most deadly skin neoplasm in the United States. Outcomes for this lethal disease have improved dramatically due to the use of both targeted and immunostimulatory drugs. Immunogenic cell death (ICD) has emerged as another approach for initiating antitumor immunity. ICD is triggered by tumor cells that display damage-associated molecular patterns (DAMPs). These DAMP molecules recruit and activate dendritic cells (DCs) that present tumor-specific antigens to T cells which eliminate neoplastic cells. Interestingly, the expression of DAMP molecules occurs in an endoplasmic reticulum (ER) stress-dependent manner. We have previously shown that ER stress was required for the cytotoxic activity of the endocannabinoid metabolite, 15-deoxy, Δ12,14 prostamide J2 (15dPMJ2). As such, the current study investigates whether 15dPMJ2 induces DAMP signaling in melanoma. In B16F10 cells, 15dPMJ2 caused a significant increase in the cell surface expression of calreticulin (CRT), the release of ATP and the secretion of high-mobility group box 1 (HMGB1), three molecules that serve as surrogate markers of ICD. 15dPMJ2 also stimulated the cell surface expression of the DAMP molecules, heat shock protein 70 (Hsp70) and Hsp90. In addition, the display of CRT and ATP was increased by 15dPMJ2 to a greater extent in tumorigenic compared to non-tumorigenic melanocytes. Consistent with this finding, the activation of bone marrow-derived DCs was upregulated in co-cultures with 15dPMJ2-treated tumor compared to non-tumor melanocytes. Moreover, 15dPMJ2-mediated DAMP exposure and DC activation required the electrophilic cyclopentenone double bond within the structure of 15dPMJ2 and the ER stress pathway. These results demonstrate that 15dPMJ2 is a tumor-selective inducer of DAMP signaling in melanoma.  相似文献   
7.
8.
阳洁  陈宏 《现代肿瘤医学》2020,(7):1209-1213
WT1基因位于人类染色体11p13,在80%的急性髓系白血病(acute myeloid leukemia,AML)患者中高表达,是AML预后不良的分子标志,可作为AML预后评估和微小残留病变(minimal residual disease,MRD)监测的有效指标。由于WT1在AML中均有异常高表达,故认为是一种AML抗原,可作为特异性免疫治疗的新靶点。一些小规模的临床试验证实以WT1为靶点的免疫治疗是有效的、安全的,这些免疫治疗可作为那些有高危复发风险及初始标准化疗失败的AML患者的辅助治疗。本文就近几年WT1与AML的预后及有关以WT1为靶点的主动特异性免疫治疗的研究进展予以综述。  相似文献   
9.
An important part of fundamental research in catalysis is based on theoretical and modeling foundations which are closely connected with studies of single-crystalline catalyst surfaces. These so-called model catalysts are often prepared in the form of epitaxial thin films, and characterized using advanced material characterization techniques. This concept provides the fundamental understanding and the knowledge base needed to tailor the design of new heterogeneous catalysts with improved catalytic properties. The present contribution is devoted to development of a model catalyst system of CeO2 (ceria) on the Cu(111) substrate. We propose ways to experimentally characterize and control important parameters of the model catalyst—the coverage of the ceria layer, the influence of the Cu substrate, and the density of surface defects on ceria, particularly the density of step edges and the density and the ordering of the oxygen vacancies. The large spectrum of controlled parameters makes ceria on Cu(111) an interesting alternative to a more common model system ceria on Ru(0001) that has served numerous catalysis studies, mainly as a support for metal clusters.  相似文献   
10.
氯吡格雷防治动脉粥样硬化缺血性疾病的研究进展   总被引:12,自引:0,他引:12  
氯吡格雷防治动脉粥样硬化斑块破裂后血栓形成尤其是冠状动脉疾病及其经皮冠脉介入性治疗有了充足的临床试验证据,对于粥样斑块的形成和发展的相关依据正在进行,现就氯吡格雷全面预防和治疗动脉粥样硬化缺血性疾病的研究进展作一综述。  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