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   5388篇
  免费   357篇
  国内免费   45篇
耳鼻咽喉   28篇
儿科学   177篇
妇产科学   115篇
基础医学   784篇
口腔科学   241篇
临床医学   407篇
内科学   1474篇
皮肤病学   128篇
神经病学   553篇
特种医学   130篇
外科学   450篇
综合类   9篇
一般理论   1篇
预防医学   245篇
眼科学   26篇
药学   356篇
中国医学   5篇
肿瘤学   661篇
  2023年   48篇
  2022年   56篇
  2021年   126篇
  2020年   113篇
  2019年   123篇
  2018年   159篇
  2017年   110篇
  2016年   137篇
  2015年   163篇
  2014年   242篇
  2013年   295篇
  2012年   467篇
  2011年   432篇
  2010年   254篇
  2009年   220篇
  2008年   402篇
  2007年   392篇
  2006年   374篇
  2005年   368篇
  2004年   306篇
  2003年   294篇
  2002年   306篇
  2001年   29篇
  2000年   14篇
  1999年   19篇
  1998年   40篇
  1997年   37篇
  1996年   24篇
  1995年   37篇
  1994年   29篇
  1993年   13篇
  1992年   18篇
  1991年   16篇
  1990年   17篇
  1989年   10篇
  1988年   10篇
  1987年   3篇
  1986年   18篇
  1985年   7篇
  1984年   8篇
  1983年   8篇
  1982年   10篇
  1981年   9篇
  1980年   5篇
  1976年   3篇
  1974年   3篇
  1973年   2篇
  1972年   2篇
  1971年   2篇
  1968年   2篇
排序方式: 共有5790条查询结果,搜索用时 15 毫秒
1.
Journal of Digital Imaging - Deep learning (DL) strategies applied to magnetic resonance (MR) images in positron emission tomography (PET)/MR can provide synthetic attenuation correction (AC) maps,...  相似文献   
2.
Journal of Interventional Cardiac Electrophysiology - Implantable cardioverter defibrillators (ICD) are widely accepted therapy in children and adolescents who are survivors of cardiac arrest or...  相似文献   
3.
Chronic hepatitis C virus (HCV) infection is the principal etiology of cirrhosis and, ultimately, hepatocellular carcinoma (HCC). At present, approximately 71 million people are chronically infected with HCV, and 10%–20% of these are expected to develop severe liver complications throughout their lifetime. Scientific evidence has clearly shown the causal association between miRNAs, HCV infection and HCC. Although it is not completely clear whether miRNA dysregulation in HCC is the cause or the consequence of its development, variations in miRNA patterns have been described in different liver diseases, including HCC. Many studies have analyzed the importance of circulating miRNAs and their effect on cell proliferation and apoptosis. In this Review, we aim to summarize current knowledge on the association between miRNA, HCV and HCC from a diagnostic point of view, and also the potential implications for therapeutic approaches.  相似文献   
4.
5.
6.
7.

Backgound

A significant proportion of hepatitis B surface antigen (HBsAg) negative/anti-hepatitis B core antigen (anti-HBc) positive patients with non-Hodgkin lymphoma (NHL) undergoing rituximab-based chemotherapy (R-CT) may suffer hepatitis B virus (HBV) reactivation.

Aims

We wanted to assess efficacy and safety of lamivudine (LMV) prophylaxis to prevent this complication.

Methods

Eighty-five consecutive HBsAg negative/anti-HBc positive NHL patients (71 years, 100% serum HBV DNA undetectable, 74% anti-HBs positive) received LMV coadministered with R-CT and for 18 months after the end of R-CT. Serum ALT, HBsAg, anti-HBs and HBV DNA were assessed every 4 months during and after end of LMV.

Results

During 39 (2–108) months of study period, including 21 months of LMV and 27 additional months after LMV discontinuation, one patient (2%) had HBV reactivation, 31 months after stopping LMV and during administration of new immunosuppressive regimens, without LMV prophylaxis, owing to incomplete oncological response. A 50% decline of anti-HBs titers occurred in 22/63 (35%) patients, including 12 who became anti-HBs seronegative. Five (6%) patients had ALT increase during R-CT but none required R-CT discontinuation. Seventeen (20%) patients died, all for tumour progression.

Conclusion

LMV prophylaxis is safe and effective in preventing HBV reactivation in HBsAg negative/anti-HBc positive NHL patients receiving R-CT.  相似文献   
8.
9.
Bucello  Sebastiano  Annovazzi  Pietro  Ragonese  Paolo  Altieri  Marta  Barcella  Valeria  Bergamaschi  Roberto  Bianchi  Alessia  Borriello  Giovanna  Buscarinu  Maria Chiara  Callari  Graziella  Capobianco  Marco  Capone  Fioravante  Cavalla  Paola  Cavarretta  Rosella  Cortese  Antonio  De Luca  Giovanna  Di Filippo  Massimiliano  Dattola  Vincenzo  Fantozzi  Roberta  Ferraro  Elisabetta  Filippi  Maria Maddalena  Gasperini  Claudio  Grimaldi  Luigi Maria Edoardo  Landi  Doriana  Re  Marianna Lo  Mallucci  Giulia  Manganotti  Paolo  Marfia  Girolama Alessandra  Mirabella  Massimiliano  Perini  Paola  Pisa  Marco  Realmuto  Sabrina  Russo  Margherita  Tomassini  Valentina  Torri-Clerici  Valentina Liliana Adriana  Zaffaroni  Mauro  Zuliani  Cristina  Zywicki  Sofia  Filippi  Massimo  Prosperini  Luca 《Journal of neurology》2021,268(8):2922-2932
Journal of Neurology - To identify baseline factors associated with disease activity in patients with relapsing–remitting multiple sclerosis (RRMS) under teriflunomide treatment. This was an...  相似文献   
10.
Phthalates are found in different plastic materials, such as packaging, toys and medical devices. Some of these compounds are endocrine disruptors, comprising substances that are able to induce multiple hormonal disturbances and downstream developmental effects, including the disruption of androgen‐dependent differentiation of the male reproductive tract and changes in pathways that regulate hormone‐dependent behaviours. In a previous study, metabolites of diisopentyl phthalate (DiPeP), a potent anti‐androgenic phthalate, were found in the urine of Brazilian pregnant women. Therefore, the present study aimed to evaluate the effects of DiPeP exposure during critical developmental periods on behaviours controlled by sex hormones in rats. Pregnant Wistar rats were treated with DiPeP (1, 10 or 100 mg kg day‐1) or canola oil by oral gavage between gestational day 10 and post‐natal day (PND) 21. Male offspring were tested in a behavioural battery, including the elevated plus maze task, play behaviour, partner preference and sexual behaviour. After the behavioural tests, the hypothalamus and pituitary of these animals were removed on PND 60‐65 and PND 145‐160 to quantify gene expression for aromatase, androgen receptor (Ar) and oestrogen receptors α (Esr1) and β (Esr2). Male rats exposed to 1 and 10 mg kg day‐1 DiPeP displayed no preference for the female stimulus rat in the partner preference test and 1 mg kg day‐1 DiPeP rats also showed a significant increase in mount and penetration latencies when mated with receptive females. A decrease in pituitary Esr1 expression was observed in all DiPeP treated groups regardless of age. A reduction in hypothalamic Esr1 expression in rats exposed to 10 mg kg day‐1 DiPeP was also observed. No significant changes were found with respect to Ar, Esr2 and aromatase expression in the hypothalamus. These results suggest that DiPeP exposure during critical windows of development in rats may induce changes in behaviours related to mating and the sexual motivation of males.  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