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   890篇
  免费   31篇
  国内免费   65篇
耳鼻咽喉   2篇
儿科学   54篇
妇产科学   13篇
基础医学   69篇
口腔科学   36篇
临床医学   137篇
内科学   215篇
皮肤病学   24篇
神经病学   7篇
特种医学   244篇
外科学   42篇
综合类   29篇
预防医学   25篇
眼科学   15篇
药学   40篇
肿瘤学   34篇
  2021年   7篇
  2020年   2篇
  2019年   3篇
  2018年   3篇
  2017年   6篇
  2016年   5篇
  2015年   16篇
  2014年   14篇
  2013年   22篇
  2012年   9篇
  2011年   11篇
  2010年   30篇
  2009年   41篇
  2008年   13篇
  2007年   55篇
  2006年   21篇
  2005年   16篇
  2004年   11篇
  2003年   6篇
  2002年   11篇
  2001年   15篇
  2000年   10篇
  1999年   16篇
  1998年   61篇
  1997年   69篇
  1996年   70篇
  1995年   59篇
  1994年   42篇
  1993年   49篇
  1992年   8篇
  1991年   14篇
  1990年   13篇
  1989年   39篇
  1988年   22篇
  1987年   36篇
  1986年   12篇
  1985年   25篇
  1984年   15篇
  1983年   23篇
  1982年   19篇
  1981年   17篇
  1980年   20篇
  1979年   1篇
  1978年   5篇
  1977年   9篇
  1976年   4篇
  1975年   6篇
  1966年   2篇
  1948年   1篇
  1947年   1篇
排序方式: 共有986条查询结果,搜索用时 0 毫秒
11.
A cell line, designated RS4;11, was established from the bone marrow of a patient in relapse with an acute leukemia that was characterized by the t(4;11) chromosomal abnormality. The cell line and the patient's fresh leukemic cells both had the t(4;11)(q21;q23) and an isochromosome for the long arm of No. 7. Morphologically, all cells were lymphoid in appearance. Ultrastructurally and cytochemically, approximately 30% of the cells possessed myeloid features. The cells were strongly positive for terminal deoxynucleotidyl transferase. They were HLA-DR positive and expressed surface antigens characteristic for B lineage cells, including those detected by anti-B4, BA-1, BA-2, and PI153/3. Immunoglobulin gene analysis revealed rearrangements of the heavy chain and kappa chain genes. The cells lacked the common acute lymphoblastic leukemia antigen and antigenic markers characteristic of T lineage cells. The cells reacted with the myeloid antibody 1G10 but not with other myeloid monoclonal antibodies. Treatment with 12-O-tetradecanoyl- phorbol-13-acetate induced a monocyte-like phenotype demonstrated by cytochemical, functional, immunologic, and electron microscopic studies. The expression of markers of both early lymphoid and early myeloid cells represents an unusual phenotype and suggests that RS4;11 represents a cell with dual lineage capabilities. To our knowledge, RS4;11 is the first cell line established from t(4;11)-associated acute leukemia.  相似文献   
12.
锌酞菁脂质体光动力作用引起小鼠肿瘤的细胞程序性死亡   总被引:3,自引:1,他引:3  
电镜观察了锌酞菁脂质体光动力作用引起小鼠MS-2纤维肉瘤的形态学变化。发现其作用很强,并对肿瘤细胞有明显的直接影响。肿瘤细胞的结构表现出明显的程序性细胞死亡(apoptosis,programmedceldeath)的特点:胞核染色质凝聚边集、核固缩、核破裂、染色质凝块流失、胞质内吞噬现象、胞膜表面肿胀粗钝的胞突形成、细胞碎裂等。加深了对锌酞菁脂质体光敏作用机理的认识,但其详细的发生机制和调节途径有待阐明。  相似文献   
13.
14.
15.
The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use.  相似文献   
16.
Digital imaging of the chest   总被引:4,自引:0,他引:4  
During the past several years, image acquisition in nuclear medicine, computed tomography, ultrasonography, subtraction angiography, and magnetic resonance has been by digitization. Despite these advances, research in the development of digital imaging in conventional radiography has lagged behind. Although studies with a variety of digital techniques have been carried out on several fronts, we still do not possess a method that has captured the imagination of the majority of radiologists and other physicians to a point where it could replace conventional screen-film imaging. This article reviews the current status and general principles of the technology, focusing on the four digital radiographic techniques that have shown the greatest promise - film digitization, an image intensifier - based system, photostimulable phosphor plates, and a scanned projection system. The physical aspects of each of the four systems and the clinical results that have been reported to date, as well as the advantages and disadvantages of each system, are presented.  相似文献   
17.

Background

Products containing dexpanthenol are used to treat irritated and inflamed skin. So far there is a lack of data for the evidence of patient-relevant benefits.

Objective

Assessment of the patient-relevant benefit of ointments containing dexpanthenol in the self-medicated therapy of irritated skin.

Methods

Prospective, observational study in a network of 392 pharmacies. Consecutive recruitment of n=1,886 patients with symptoms of irritated skin, including non-inflammatory intervals of atopic eczema, other xerotic skin conditions and impairment of skin barrier. The patient-relevant benefit was ascertained prior to and 7–10 days after treatment through the patient-benefit index (PBI).

Results

The PBI showed that 91.5% of the patients experienced a relevant benefit from treatment. 94.7% directly indicated to have had achieved successful therapeutic results. All symptoms of irritated skin (e.g. xerosis, erythema, desquamation) significantly improved (p≤0,001). The subjective response was independent of age, gender and underlying skin disease.

Conclusion

High patient-relevant benefits were observed in the treatment of irritated skin with dexpanthenol ointment.  相似文献   
18.
多索茶碱及其片剂的高效液相色谱分析   总被引:3,自引:0,他引:3  
多索茶碱及其片剂的高效液相色谱分析刘春胜,何秀峰,王云萍,谷士杰,周同惠(中国医学科学院、中国协和医科大学药物研究所,北京100050)多索茶碱(doxofylline)是用于治疗支气管哮喘合并支气管痉挛的慢性阻塞性肺部疾病的新一代黄嘌吟衍生物,其药...  相似文献   
19.
The authors evaluated magnetic resonance (MR) images obtained with intravenously administered gadolinium in ten patients who had facial paralysis and no facial nerve tumor. In patients with either Bell palsy (four patients) or facial paralysis after temporal bone surgery (six patients), intratemporal facial nerve enhancement was seen. Facial nerve enhancement on MR images proved to be a nonspecific finding.  相似文献   
20.
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