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   50879篇
  免费   5155篇
  国内免费   1873篇
耳鼻咽喉   411篇
儿科学   410篇
妇产科学   497篇
基础医学   6101篇
口腔科学   1369篇
临床医学   5314篇
内科学   5545篇
皮肤病学   444篇
神经病学   3470篇
特种医学   1746篇
外国民族医学   1篇
外科学   4635篇
综合类   8918篇
现状与发展   4篇
预防医学   7686篇
眼科学   806篇
药学   5357篇
  84篇
中国医学   2922篇
肿瘤学   2187篇
  2024年   321篇
  2023年   1163篇
  2022年   2285篇
  2021年   2693篇
  2020年   2312篇
  2019年   1885篇
  2018年   1753篇
  2017年   1932篇
  2016年   1771篇
  2015年   1962篇
  2014年   3329篇
  2013年   3718篇
  2012年   3045篇
  2011年   3474篇
  2010年   2676篇
  2009年   2785篇
  2008年   2706篇
  2007年   2648篇
  2006年   2268篇
  2005年   1975篇
  2004年   1558篇
  2003年   1372篇
  2002年   1040篇
  2001年   921篇
  2000年   852篇
  1999年   716篇
  1998年   549篇
  1997年   513篇
  1996年   439篇
  1995年   407篇
  1994年   384篇
  1993年   293篇
  1992年   294篇
  1991年   209篇
  1990年   224篇
  1989年   178篇
  1988年   152篇
  1987年   158篇
  1986年   112篇
  1985年   158篇
  1984年   117篇
  1983年   74篇
  1982年   86篇
  1981年   80篇
  1980年   69篇
  1979年   62篇
  1978年   45篇
  1977年   32篇
  1976年   35篇
  1975年   20篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
ObjectiveReview the applicability of the Transtheoretical model and provide updated guidance for clinicians working with women experiencing intimate partner violence.MethodsCritical review of related primary research conducted from 1990 to March 2013.ResultsWomen's experiences of creating change within abusive relationships can be located within a stages of change continuum by identifying dominant behavioral clusters. The processes of change and constructs of decisional-balance and turning-points are evident in women's decision-making when they engage in change.ConclusionClinicians can use the stages of change to provide a means of assessing women's movement toward their nominated outcomes, and the processes of change, decisional-balance and turning-points, to enhance understanding of, and promote women's movement across stages in their journey to safety.Practice implicationsClinicians should assess women individually for immediate and ongoing safety and well-being, and identify their overarching stage of change. Clinicians can support women in identifying and implementing their personal objectives to enhance self-efficacy and create positive change movement across stages.The three primary objectives identified for clinician support are: 1. Minimizing harm and promoting well-being within an abusive relationship, 2. Achieving safety and well-being within the relationship; halting the abuse, or 3. Achieving safety by ending/leaving intimate relationships.  相似文献   
994.
Eukaryotic translation initiation factor 5A (eIF5A) is a small acidic protein highly conserved from archaea to mammals. eIF5A is the only protein which undergoes a unique lysine residue modification to hypusine. Hypusinylation is important for the function of eIF5A which is reported to be essential for cell viability. eIF5A promotes formation of the first peptide bond at the onset of protein synthesis. However, its function in Leishmania donovani is unclear. The present study focuses on the characterization and localization of L. donovani eIF5A protein. The eIF5A gene contains an ORF of 501×bp encoding 166 amino acid residues with a predicted molecular mass and isoelectric point of 17.8 kDa and 4.83 respectively. A phylogenetic tree analysis revealed its close proximity to trypanosomes however it is distantly located from Trichomonas vaginalis and Plasmodium falciparum. The L. donovani eIF5A was expressed as a 6× His tagged protein whose identity was confirmed by western blot and MALDI. Biophysical investigation by CD revealed the predominant presence of 49% β sheet structure which correlated well with secondary structure prediction. To gain insight into the role of eIF5A in L. donovani, we investigated the subcellular distribution of eIF5A. A GFP-fusion of L. donovani eIF5A was found to be localized in cytoplasm as confirmed by subcellular fractionation. Our studies indicated that eIF5A is primarily localized to cytoplasm and is undetectable in nuclear fraction. The homology model of eIF5A of L. donovani was built and the resulting model showed acceptable Ramachandran statistics. The model is reliable and can be used to study eIF5A binding with its effector molecules.  相似文献   
995.
Shigellosis is a worldwide disease, characterized by abdominal pain, fever, vomiting, and the passage of blood‐ and mucus‐streaked stools. Rhesus monkeys and other primates are the only animals that are naturally susceptible to shigellosis. A suitable animal model is required for the pre‐clinical evaluation of vaccines candidates. In this study, the minimal dose of Shigella dysenteriae1 1617 strain required to produce dysentery in four of five (80% attack rate) monkeys using an escalating dose range for three groups [2 × 108, 2 × 109 and 2 × 1010 colony forming unit (CFU)] was determined. In addition, the monkeys were re‐infected. The identified optimal challenge dose was 2 × 109 CFU; this dose elicited 60% protection in monkeys when they were re‐challenged with a one log higher dose (2 × 1010 CFU). The challenge dose, 2 × 1010 CFU, produced severe dysentery in all monkeys, with one monkey dying within 24 h, elicited 100% protection when re‐challenged with the same dose. All monkeys exhibited immune responses. This study concludes that the rhesus monkey model closely mimics the disease and immune response seen in humans and is a suitable animal model for the pre‐clinical evaluation of Shigella vaccine candidates. Prior infection with the 1617 strain can protect monkeys against subsequent re‐challenges with homologous strains.  相似文献   
996.
997.
目的研究SIRS模型肠组织中TFmRNA的表达,探讨TF在SIRS发生中的作用。方法40只新生Wistar大鼠,出生36h~48h,随机分成正常对照组(A组)10只及模型组(B组)30只。48小时后处死动物,根据血液白细胞总数及呼吸改变确定为SIRS。将B组分为未发生SIRS组(B1组)和发生SIRS组(B2组)。实时荧光定量聚合酶链反应(QRT—PCR)检测肠组织TFmRNA的表达。结果肠组织Ⅱ1瑚RNA表达水平(2-△△Ct值):A组1.01±0.04,B1组2.14±0.19,B2组3.78±1.2,三组间比较差异有显著性(P〈0.05)。结论从转录水平证实,SIRS新生大鼠模型中,TF水平增加.提示TF参与炎症反应。  相似文献   
998.
BACKGROUND Post-transplant dyslipidemia(PTDL) is a common complication in liver recipients and can cause morbidity and threaten graft function. The crosstalk between metabolic inflammation and dyslipidemia has been recently revealed. However,the role of grafts' and recipients' metabolic status in the development of PTDL has not been evaluated.AIM To investigate the association of recipients' metabolic inflammation status with PTDL and construct a predictive model.METHODS A total of 396 adult patients who received primary liver transplantation between2015 and 2017 were enrolled. Metabolomics and cytokines were analyzed using recipients' pre-transplant peripheral blood in a training set(n = 72). An integrated prediction model was established according to the clinical risk factors and metabolic inflammation compounds and further verified in a validation set(n = 144).RESULTS The serum lipid profile took 3 mo to reach homeostasis after liver transplantation.A total of 278(70.2%) liver recipients developed PTDL during a follow-up period of 1.78(1.00, 2.97) years. The PTDL group showed a significantly lower tumorfree survival and overall survival than the non-PTDL group in patients with hepatocellular carcinoma(n = 169). The metabolomic analysis showed that metabolic features discriminating between the PTDL and non-PTDL groups were associated with lipid and glucose metabolism-associated pathways. Among metabolites and cytokines differentially expressed between the two groups,interleukin-12(p70) showed the best diagnostic accuracy and significantly increased the predictive value when it was incorporated into the clinical model in both training and validation sets.CONCLUSION Recipients' pre-transplant serum interleukin-12(p70) level is associated with the risk of PTDL and has potential clinical value for predicting PTDL.  相似文献   
999.
年资积分是PF医师费制度中体现医疗团队合作、实践经验传承的重要部分。作者以清华大学附属北京清华长庚医院为样本,以医师职业进阶路径为基础,结合培养年限,架构出公立医院年资积分设计的基本模型。该模型既体现尊师重教的基本职业伦理,又激励年轻医师追求卓越。  相似文献   
1000.
Modern clinical trials have produced controversial data interpretation which refutes conventional standard teachings and practices. Acupuncture scholars and practitioners have been stimulated to scrutinize these trials and analyze conventional practices. This paper presents two acupuncture models which address these issues. One rationalizes the clinical trial results with newer understanding of acupuncture points and techniques, while the other reconciles these results with rediscovered techniques of palpating points and performing needling. These two models indicate that acupuncture is in transition from classical model to evidence-based models.  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