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   2435篇
  免费   97篇
  国内免费   25篇
耳鼻咽喉   40篇
儿科学   126篇
妇产科学   139篇
基础医学   301篇
口腔科学   43篇
临床医学   152篇
内科学   480篇
皮肤病学   67篇
神经病学   205篇
特种医学   74篇
外科学   134篇
综合类   26篇
一般理论   1篇
预防医学   237篇
眼科学   117篇
药学   259篇
中国医学   2篇
肿瘤学   154篇
  2024年   2篇
  2023年   19篇
  2022年   90篇
  2021年   123篇
  2020年   41篇
  2019年   55篇
  2018年   66篇
  2017年   54篇
  2016年   57篇
  2015年   78篇
  2014年   101篇
  2013年   112篇
  2012年   208篇
  2011年   205篇
  2010年   116篇
  2009年   94篇
  2008年   143篇
  2007年   130篇
  2006年   155篇
  2005年   149篇
  2004年   148篇
  2003年   124篇
  2002年   114篇
  2001年   10篇
  2000年   3篇
  1999年   17篇
  1998年   21篇
  1997年   27篇
  1996年   18篇
  1995年   10篇
  1994年   18篇
  1993年   13篇
  1992年   2篇
  1991年   6篇
  1990年   1篇
  1989年   6篇
  1988年   5篇
  1986年   1篇
  1985年   4篇
  1984年   2篇
  1983年   1篇
  1982年   1篇
  1981年   1篇
  1980年   1篇
  1977年   2篇
  1975年   2篇
  1966年   1篇
排序方式: 共有2557条查询结果,搜索用时 12 毫秒
81.
Porter  JB; Hoyes  KP; Abeysinghe  RD; Brooks  PN; Huehns  ER; Hider  RC 《Blood》1991,78(10):2727-2734
Five orally effective iron chelators of the 3-hydroxypyridin-4-one series have been administered intraperitoneally to iron-overloaded and nonoverloaded male mice at a dose of 200 mg/kg/24 h for a total of 60 days to investigate the effect on iron loading and toxicity. There was a significant reduction in hepatic iron at the end of the study in the iron-overloaded mice with all compounds studied using chemical iron quantitation (P less than .001) and with Perls' stain (P less than .01). Liver iron removal with the hydroxypyridinones ranged from 37% with CP20 to 63% with CP51, compared with 46% removal for desferrioxamine (DFO). There was no significant reduction in splenic or cardiac iron with any chelator. There were no deaths in iron-overloaded animals receiving any of the hydroxypyridin-4-ones, but significantly more deaths in the nonoverloaded groups as a whole (P less than .03). No weight loss was observed with any chelator. Significant reductions in hemoglobin and white cell count were observed with CP20(L1). No histologic abnormalities of kidney, spleen, bone marrow, or stifle joints were observed. Intracytoplasmic inclusion bodies were observed in the centrilobular hepatocytes of animals administered each of the hydroxypyridin-4-ones, while the DFO-treated and control groups showed no such changes.  相似文献   
82.

Objectives

To evaluate sensitization to chemicals present in work environment after an outbreak of contact dermatitis in workers of vehicle equipment factory, exposed to polyurethane foam, based on 4,4′-diphenylmethane diisocyanate (MDI).

Material and Methods

From among 300 employees, 21 individuals reporting work-related skin and/or respiratory tract symptoms underwent clinical examination, patch testing, skin prick tests, spirometry and MDI sIgE measurement in serum. Patch tests included isocyanates series, selected rubber additives, metals, fragrances, preservatives, and an antiadhesive agent.

Results

Clinical examination revealed current eczema in the area of hands and/or forearms in 10 workers. Positive patch test reactions were found in 10 individuals, the most frequent to diaminodiphenylmethane and 4-phenylenediamine (7 persons). Reactions to an antiadhesive agent were assessed as irritant (5 workers). Except for sensitization to common aeroallergens, no significant abnormalities were found in the remaining tests. Occupational allergic contact dermatitis was diagnosed in 7 workers, irritant contact dermatitis in 10 and coexisiting allergic and irritant contact dermatitis in 3 workers.

Conclusions

In workers manufacturing products from polyurethane foam, attention should be paid to the risk of developing contact dermatitis. Skin problems in our study group were attributable probably to insufficient protection of the skin.  相似文献   
83.
The article presents a systematic review protocol. The aim of the study is an assessment of current studies regarding the application of artificial intelligence and neural networks in the screening for adverse perinatal outcomes. We intend to compare the reported efficacy of these methods to improve pregnancy care and outcomes. There are more and more studies that describe the role of machine learning in facilitating the diagnosis of adverse perinatal outcomes, like gestational diabetes or pregnancy hypertension. A systematic review of available literature seems to be crucial to compare the known efficacy and application. Publication of a systematic review in this category would improve the value of future studies. The studies reporting on artificial intelligence application will have a major impact on future prenatal practice.  相似文献   
84.
Suszek  Dorota  Górak  Anna  Majdan  Maria 《Rheumatology international》2020,40(10):1625-1629
Rheumatology International - New markers of systemic lupus erythematosus (SLE) activity are under investigation. In recent years, the researchers have been focusing increased attention on the role...  相似文献   
85.
86.
87.
88.
Skeletal involvement is a rare complication of hairy cell leukemia (HCL) with an incidence of approximately 3%. Bone lesions are commonly lytic, and the most common sites of involvement are the femoral head and neck. Skeletal involvement is typically associated with high tumor burden and bone marrow infiltration. However, isolated cases of skeletal disease without splenomegaly or bone marrow involvement are occasionally reported. This review focuses on skeletal lesions in HCL, particularly the pathogenesis, clinical symptoms, diagnostic methods, and treatment approach. A literature review of the MEDLINE database for articles in English concerning hairy cell leukemia, skeletal symptoms, bone involvement was conducted via PubMed. Publications from January 1970 to May 2020 were scrutinized. Additional relevant publications were obtained by reviewing the references from the chosen articles.  相似文献   
89.
Non‐HLA antibodies (Abs) targeting vascular receptors are thought to have an impact on renal transplant injury. Anti‐angiotensin II type 1‐receptor‐activating antibodies (anti‐AT1R) have been mentioned to stimulate a severe vascular rejection, but the pretransplant screening has not been introduced yet. The aim of our study was to assess the incidence and importance of anti‐AT1R antibodies and their influence on renal transplant in the 1st year of observation. We prospectively evaluated the presence of anti‐AT1R antibodies in 117 consecutive renal transplant recipients in pre‐ and post‐transplant screening. Anti‐AT1R antibodies were observed in 27/117 (23%) of the analyzed recipients already before transplantation. The function of renal transplant was considerably worse in anti‐AT1R(+) group. The patients with anti‐AT1R Abs >9 U/ml lost their graft more often. Biopsy‐proven AR was described in 4/27 (15%) pts in the anti‐AT1R(+) group and 13/90 (14.4%) in the anti‐AT1R(?) group, but more severe cases of Banff IIB or antibody‐mediated rejection (AMR) were more often observed in anti‐AT1R (+) 4/27 (15%) vs. 1/90 (1.1%) in anti‐AT1R(+) (P = 0.009). Patients with anti‐AT1R Abs level >9 U/ml run a higher risk of graft failure independently of classical immunological risk factors. The recipients with anti‐AT1R Abs developed more severe acute rejections described as IIB or AMR in Banff classification. More recipients among the anti‐AT1R‐positive ones lost the graft. Our study suggests monitoring of anti‐AT1R Abs before renal transplantation for assessment of immunologic risk profiles and the identification of patients highly susceptible to immunologic events, graft failure, and graft loss.  相似文献   
90.
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