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   2018篇
  免费   119篇
  国内免费   4篇
耳鼻咽喉   20篇
儿科学   52篇
妇产科学   33篇
基础医学   352篇
口腔科学   17篇
临床医学   180篇
内科学   276篇
皮肤病学   103篇
神经病学   263篇
特种医学   71篇
外国民族医学   1篇
外科学   189篇
综合类   5篇
预防医学   212篇
眼科学   72篇
药学   164篇
中国医学   1篇
肿瘤学   130篇
  2023年   8篇
  2022年   12篇
  2021年   35篇
  2020年   36篇
  2019年   48篇
  2018年   50篇
  2017年   45篇
  2016年   57篇
  2015年   57篇
  2014年   58篇
  2013年   100篇
  2012年   145篇
  2011年   174篇
  2010年   92篇
  2009年   83篇
  2008年   161篇
  2007年   149篇
  2006年   146篇
  2005年   141篇
  2004年   88篇
  2003年   68篇
  2002年   69篇
  2001年   17篇
  2000年   12篇
  1999年   24篇
  1998年   17篇
  1997年   10篇
  1996年   10篇
  1995年   15篇
  1994年   5篇
  1993年   6篇
  1992年   14篇
  1991年   8篇
  1990年   10篇
  1989年   10篇
  1988年   9篇
  1987年   5篇
  1986年   13篇
  1985年   9篇
  1984年   7篇
  1983年   8篇
  1980年   6篇
  1979年   8篇
  1978年   5篇
  1977年   10篇
  1975年   4篇
  1965年   4篇
  1963年   4篇
  1956年   4篇
  1932年   5篇
排序方式: 共有2141条查询结果,搜索用时 15 毫秒
1.
Follow up MRI study in first episode schizophrenia.   总被引:2,自引:0,他引:2  
  相似文献   
2.
OBJECTIVES: Tumor necrosis factor-alpha (TNF-alpha) is recognized as a likely mediator of the excessive endothelial activation and injury that is a key pathogenetic mechanism of preeclampsia. We used whole blood cell cultures from 12 patients with severe preeclampsia and from 12 healthy pregnant and nonpregnant women to determine the release of TNF-alpha by unstimulated leukocytes as a measure of their state of activation, and their response to stimulation with lipopolysaccharide (LPS) as an indicator of their state of priming. METHODS: Blood was cultivated without and with LPS, and TNF-alpha release was measured after six and 24 hours of cultivation by enzyme-linked immunoassays. Differential leukocyte counts were performed, and TNF-alpha values calculated per 10(5) monocytes. RESULTS: In unstimulated whole blood cultures, TNF-alpha release after six hours of cultivation was similar in all three groups; but after 24 hours, TNF-alpha concentrations in culture supernatants from preeclamptic patients were significantly higher than were values obtained in blood from normotensive pregnant women. In LPS-stimulated blood cultures with a maximum of TNF-alpha release at six hours cultivation time, TNF-alpha concentrations were significantly lower in preeclamptic women than they were in both control groups. We showed in an additional experiment that a strong LPS challenge following preactivation with high doses of LPS resulted in reduced release of TNF-alpha compared with release of TNF-alpha following preactivation with low doses of LPS. CONCLUSIONS: The observed high capacity for spontaneous TNF-alpha release by leukocytes in preeclampsia indicates activation of TNF-alpha producing leukocytes by the disease process. Preactivation and exhaustion of leukocytes by leakage of TNF-alpha could lead to the reduced response to TNF-alpha inducer LPS as observed in blood cultures from preeclamptic patients.  相似文献   
3.
4.
This paper describes the results of an asthma self-management protocol delivered to parents of children aged 0-4 years. The protocol was delivered by general practitioners (GPs), community nurses, asthma nurses, and doctors in child health centers. It consisted of 16 educational modules developed after an initial needs assessment of parents and a task analysis of primary care practitioners. The program was evaluated by means of an experimental design. Parents participating in the program had significantly more knowledge, a more favorable attitude toward asthma, and a higher self-efficacy score with respect to performing asthma self-management behaviors. Also, they reported performing self-management behaviors more frequently than parents in the control group. One-year follow-up results, which were collected for parents in the treatment group only, showed that the described changes were sustained. Further, the treatment group was found to have decreased its emergency and nonemergency use of the physician's office and to have a reduction in (reported) asthma severity. Process evaluation indicated that most modules were provided by the GPs to nearly all parents. After parents had read the modules at home, almost all the information was discussed in the next contact. GPs seldom referred patients to the community nurses, although this was suggested in the protocol.  相似文献   
5.
We report two cases of Sneddon's syndrome. Both cases had widespread livedo reticularis with repeated cerebrovascular accidents without persistent neurological deficit. In one case, hemostatic examination revealed an imbalance of plasminogen activator-inhibitor values, possibly related to the thrombogenic propensity of the syndrome. Treatment with acetylsalicylic acid led to normalization of hemostatic parameters and resulted in a symptom-free period of more than 10 months. The importance of hemostatic screening in patients with Sneddon's syndrome is discussed.  相似文献   
6.
Probiotics as flourishing benefactors for the human body.   总被引:2,自引:0,他引:2  
This article provides a comprehensive review of the beneficial effects of various strains of probiotics in preventing and treating certain diseases. Currently, changed lifestyles as well as the increased use of antibiotics are significant factors challenging the preservation of a healthy intestinal microflora. The concept of probiotics is to restore and uphold a microflora advantageous for the human body. Probiotics are found in a number of fermented dairy products, infant formula, and dietary supplements. In the presence of prebiotics, which are nondigestible food ingredients favorable for probiotic growth, their survival in the intestine is ameliorated.  相似文献   
7.
8.
The human wild-type (wt) p53.264-272 peptide is a universal tumor antigen and recognized by HLA-A*0201 (A2.1)-restricted CTL. Generation of this epitope by constitutive 20S proteasomes is prevented by a p53 R to H hotspot mutation at the C-terminal flanking residue 273. We report on the impact of the interferon-gamma (IFN-gamma)-inducible proteasomal activator PA28 (11S regulator) and the immunoproteasome on the in vitro and cellular processing of wt and mutant (mut) p53 substrates. We found that production of the antigenic 264-272 peptide from wt p53 by constitutive as well as immunoproteasomes is accelerated and amplified by the PA28 activator. PA28 and (immuno)proteasomes were not capable to reconvert the resistance of epitope release from mut p53. Maximum and accelerated antigen production in vitro and on the cellular level required the IFN-gamma-inducible interaction of immunoproteasomes and PA28. We conclude that efficient processing of p53.264272 from wt p53 is governed by the proteasome/PA28 complex. These studies have important implications for p53-specific cancer immunotherapy and demonstrate that the effects of the immunoproteasome and PA28 are influenced by the individual epitope and its flanking sequence context.  相似文献   
9.
In order to investigate the role of the ferric uptake regulator Fur in the porcine lung pathogen Actinobacillus pleuropneumoniae, we constructed an isogenic in-frame deletion mutant, A. pleuropneumoniae Deltafur. This mutant showed constitutive expression of transferrin-binding proteins, growth deficiencies in vitro, and reduced virulence in an aerosol infection model.  相似文献   
10.
Upon the discovery of numerous genes involved in the pathogenesis of neurodevelopmental disorders, several studies showed that a significant proportion of these genes converge on common pathways and protein networks. Here, we used a reversed approach, by screening the AnkyrinG protein-protein interaction network for genetic variation in a large cohort of 1009 cases with neurodevelopmental disorders. We identified a significant enrichment of de novo potentially disease-causing variants in this network, confirming that this protein network plays an important role in the emergence of several neurodevelopmental disorders.Subject terms: Genetics research, Neurological disorders  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