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   1587篇
  免费   103篇
  国内免费   12篇
耳鼻咽喉   10篇
儿科学   50篇
妇产科学   18篇
基础医学   297篇
口腔科学   11篇
临床医学   122篇
内科学   245篇
皮肤病学   305篇
神经病学   77篇
特种医学   60篇
外科学   107篇
综合类   18篇
一般理论   2篇
预防医学   59篇
眼科学   9篇
药学   90篇
中国医学   1篇
肿瘤学   221篇
  2022年   9篇
  2021年   13篇
  2019年   11篇
  2018年   15篇
  2017年   18篇
  2016年   22篇
  2015年   24篇
  2014年   23篇
  2013年   44篇
  2012年   48篇
  2011年   49篇
  2010年   35篇
  2009年   36篇
  2008年   65篇
  2007年   60篇
  2006年   64篇
  2005年   76篇
  2004年   91篇
  2003年   67篇
  2002年   79篇
  2001年   69篇
  2000年   65篇
  1999年   55篇
  1998年   28篇
  1997年   34篇
  1996年   28篇
  1995年   26篇
  1994年   25篇
  1993年   21篇
  1992年   52篇
  1991年   43篇
  1990年   36篇
  1989年   30篇
  1988年   28篇
  1987年   27篇
  1986年   23篇
  1985年   14篇
  1984年   26篇
  1983年   10篇
  1979年   19篇
  1978年   11篇
  1977年   9篇
  1976年   14篇
  1975年   13篇
  1974年   19篇
  1973年   19篇
  1972年   12篇
  1971年   12篇
  1970年   16篇
  1969年   8篇
排序方式: 共有1702条查询结果,搜索用时 0 毫秒
991.
992.
ISCL/EORTC推荐蕈样肉芽肿协作组使用皮肤T细胞淋巴瘤(Cutaneous T-cell lymphoma,CTCL)分类及分期修订方案.这个修订方案吸收了自1979年最初的指南发表以来的有关蕈样肉芽肿(MycosisFungoides,MF)和Sézary综合征(Sézary syndrome,SS)肿瘤细胞生物学和诊断技术的进展,明确目前影响研究机构和调查者之间有效交流和(或)MF及SS标准化临床实验发展的某些指标,而且为追踪其他有潜在预后意义的指标提供了一个平台.此外,鉴于皮肤淋巴瘤中非MF/非SS亚型预后和临床特点的差异,本方案是特别针对MF和SS的.除了对本修订方案的评估和分期程序做出推荐外,该文还对修订方案的论据做了讨论.[Blood.2007,110(6):1713-1722]  相似文献   
993.
Fixed drug eruptions (FDEs) represent an uncommon subset of drug reactions where typically dusky red skin eruptions recur at the same site each time a drug is administered. Multifocal FDEs are defined by skin eruptions at more than one site. We describe a patient with metastatic melanoma who developed a multifocal FDE to paracetamol, tropisetron and ondansetron during chemoimmunotherapy with interleukin 2 (IL-2) and dacarbazine. This case is unique since to our knowledge there has been no previous report of such a drug reaction to tropisetron. Moreover, recurrences were induced by drugs which were chemically unrelated (i.e. tropisetron and paracetamol). We propose that this unusual skin reaction to multiple drugs was induced by IL-2 administered during immunochemotherapy for the metastatic melanoma.  相似文献   
994.
Several pathogenetic factors such as peripheral neuropathy, vasculopathy and infection are responsible for the development of diabetic foot ulcerations. An important factor contributing to the high infection risk in diabetic patients is a defect in neutrophil granulocytes. Deficiencies in neutrophil chemotaxis, phagocytosis and respiratory burst activity with the decrease of the super- and peroxids are known to be associated with diabetes. Granulocyte-colony stimulating factor (G-CSF) increases the release of neutrophils from the bone marrow and improves neutrophil function. A 78-year old patient with non-insulin-dependent diabetes presented with ulcerations of both big toes and a malum perforans on the right sole. He also had generalized arteriosclerosis as well as a polyneuropathy with a dry foot and typical foot deformation as well as decreased in sensitivity. Intensive local care for 35 days led to no improvement of the ulcerations. Then G-CSF (Neupogen) was administered in a total dose of 165 million IU over 11 days; the daily dose varied between 15-30 million IU depending on the absolute leucocyte count. In addition 500 mg of oral ciprofloxacin (Ciproxin) was given b.i.d. This treatment led to a significant improvement of the lesions. Within 11 days cost analysis suggests G-CSF may be a cost-effective addition to antimicrobial therapy in diabetic foot infection.  相似文献   
995.
CD1 proteins are a family of cell surface molecules that present lipid antigens to T cells. We investigated skin dendritic cells and monocyte-derived dendritic cells for expression of CD1 molecules using a panel of 10 different monoclonal antibodies focusing on the recently described CD1d molecule. By immunohistochemical analysis, CD1d expression in normal human skin was restricted to dendritic appearing cells in the papillary dermis mainly located in a perivascular localization. Langerhans cells did not show detectable CD1d expression in situ. Epidermal/dermal cell suspensions analyzed by flow cytometry demonstrated distinct subpopulations of HLA-DR positive dermal dendritic cells expressing CD1a, CD1b, and CD1c. CD1d was expressed on HLA-DRbright dermal antigen-presenting cells in dermal suspensions (16% +/- 3.6%), as well as on highly enriched dermal dendritic cells migrating out of skin explants (60.5% +/- 8.0%). Migrated mature dermal dendritic cells coexpressed CD83 and CD1d. Western blot analysis on microdissected skin sections revealed the presence of a 50-55 kDa CD1d molecule in dermis, suggesting that CD1d is highly glycosylated in skin. Both immature and mature monocyte-derived dendritic cells cultured in autologous plasma expressed CD1d molecules. In contrast, culture in fetal bovine serum downregulated CD1d expression. In conclusion, antigen-presenting cells in skin express different sets of CD1 molecules including CD1d and might play a role in lipid antigen presentation in various skin diseases. Differential expression of CD1 molecules depending on culture conditions might have an impact on clinical applications of dendritic cells for immunotherapy.  相似文献   
996.
INTRODUCTION: Melaleuca alternifolia is a coniferous tree found in tropical regions, the needles contain an essential oil that is used in medical and cosmetic products. The essential oil contains turpentines (limonene, alpha-pinene, phellandrene) that are potentially allergenic.PATIENTS AND METHODS: In 1997, 1216 patients were patch tested in our dermatoligic unit. Fourteen of them tested because of eczema used products containing tea tree oil. The patients used creams, hair products and essential oils containing Melaleuca alternifolia for cosmetic reasons and to treat skin affections. They were patch tested for a standard panel of allergens, topical emulgators, perfumes, plants, topical medications, metal, gloves, topical disinfectants and preservatives, dental products and rubber derivatives. Products containing Melaleuca alternifolia were tested concentrated or diluted.RESULTS: We report on 7 cases of patients with an allergic contact dermatitis due to tea tree oil. Two of them also exhibited from a delayed type IV hypersensitivity towards fragrance-mix or colophony suggesting the possibility of cross reaction or an allergic group reaction caused by contamination of the colophony with the volatile fraction of turpentines.DISCUSSION: The allergic potential of low concentrations of Melaleuca alternifolia is presumed to be low on healthy skin. Photoaged Melaleuca alternifolia must be considered to be a stronger sensitizer.  相似文献   
997.
998.
Legislation and prospective legislative proposals in for instance the USA, Europe, and Japan require, or may require that chemicals are tested for their ability to disrupt the hormonal systems of mammals. Chemicals found to test positive are considered to be endocrine active substances (EAS) and may be putative endocrine disruptors (EDs). To date, there is still little or no experience with incorporating metabolic and toxicokinetic aspects into in vitro tests for EAS. This is a situation in sharp contrast to genotoxicity testing, where in vitro tests are routinely conducted with and without metabolic capacity. Originally prepared for the Organisation of Economic Cooperation and Development (OECD), this detailed review paper reviews why in vitro assays for EAS should incorporate mammalian systems of metabolism and metabolic enzyme systems, and indicates how this could be done. The background to ED testing, the available test methods, and the role of mammalian metabolism in the activation and the inactivation of both endogenous and exogenous steroids are described. The available types of systems are compared, and the potential problems in incorporating systems in in vitro tests for EAS, and how these might be overcome, are discussed. Lastly, some recommendations for future activities are made.  相似文献   
999.
1000.
Rabbit cortical collecting tubules were perfused in vitro to investigate the control of bicarbonate transport. Bicarbonate was measured by microcalorimetry as total CO2. The perfusate and bath were identical solutions containing 25 mM bicarbonate at pH 7.4. The mean pH of the urine in the bladders of untreated rabbits at the time they were killed was 7.4. Their individual tubules, studied in vitro, either absorbed or secreted bicarbonate, and, combining the results, there was on the average no significant net transport. When the rabbits were treated with NH4Cl the day before the experiment, their urine was acidic and their tubules studied in vitro absorbed bicarbonate (i.e., there was net lumen-to-bath transport). In contrast, when the rabbits were treated with NaHCO3, their urine was significantly more alkaline, and their tubules studied in vitro generally secreted bicarbonate (i.e., net bath-to-lumen transport). Thus, the direction of bicarbonate transport by cortical collecting tubules studied under standard conditions in vitro correlated with the urine pH and was determined by the preceding treatment of the animals in vivo with acidifying or alkalinizing salts. These results demonstrate a previously unrecognized mechanism which contributes to the control of urinary bicarbonate excretion.  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