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   390篇
  免费   28篇
  国内免费   1篇
儿科学   1篇
妇产科学   1篇
基础医学   38篇
口腔科学   3篇
临床医学   13篇
内科学   30篇
皮肤病学   2篇
神经病学   261篇
特种医学   7篇
外科学   36篇
综合类   14篇
预防医学   3篇
眼科学   2篇
药学   3篇
肿瘤学   5篇
  2020年   3篇
  2019年   4篇
  2017年   2篇
  2016年   3篇
  2015年   7篇
  2014年   2篇
  2013年   4篇
  2012年   5篇
  2011年   7篇
  2010年   8篇
  2009年   11篇
  2008年   8篇
  2007年   12篇
  2006年   24篇
  2005年   18篇
  2004年   18篇
  2003年   21篇
  2002年   30篇
  2001年   29篇
  2000年   19篇
  1999年   25篇
  1998年   11篇
  1997年   14篇
  1996年   13篇
  1995年   14篇
  1994年   10篇
  1993年   8篇
  1992年   7篇
  1991年   5篇
  1990年   6篇
  1989年   6篇
  1988年   14篇
  1987年   6篇
  1986年   10篇
  1985年   7篇
  1984年   6篇
  1983年   6篇
  1982年   1篇
  1981年   1篇
  1980年   6篇
  1979年   3篇
  1978年   1篇
  1977年   1篇
  1976年   2篇
  1974年   1篇
排序方式: 共有419条查询结果,搜索用时 31 毫秒
1.
OBJECTIVE: To assess the feasibility of using archival oral mucosal tissue to examine gene expression at the ribonucleic acid (RNA) level.
MATERIALS AND METHODS: We describe the isolation of RNA from 8 nm sections of formalin-fixed paraffin-embedded oral mucosal tissue. RNA was reverse transcribed and three candidate genes amplified by polymerase chain reaction (PCR). The ribosomal protein S14 gene is a housekeeping gene which has been used as an internal standard in several quantitative PCR protocols. The thymidine kinase (TK) gene is expressed at low levels in most tissues and, with a well-documented genomic organisation, is a useful tool for discrimination between genomic DNA and cDNA. The RIa gene is reported to be overexpressed in many cancer cell lines, in malignant tissue and in vitro transformed cellS. RESULTS: The S14 gene, the TK gene and the RIα gene of the cAMP-dependent protein kinase (PKA) were amplified successfully from formalin-fixed paraffin-embedded tissue sections. The TK primer pair is a useful additional tool in the unambiguous identification of RNA-derived species.
CONCLUSION: RNA suitable for reverse transcribed (RT)-PCR was extracted from archival oral mucosal tissue. This should permit rapid sequence analysis of transcribed tumor suppressor genes and oncogenes in this material. Furthermore, the RT-PCR approach described may allow quantification of gene expression in oral mucosal archival material processed in a standard fashion.  相似文献   
2.
CD4+CD25+ regulatory T cells (T reg cells) play a key role in controlling autoimmunity and inflammation. Therefore, therapeutic agents that are capable of elevating numbers or increasing effector functions of this T cell subset are highly desirable. In a previous report we showed that a superagonistic monoclonal antibody specific for rat CD28 (JJ316) expands and activates T reg cells in vivo and upon short-term in vitro culture. Here we demonstrate that application of very low dosages of the CD28 superagonist into normal Lewis rats is sufficient to induce T reg cell expansion in vivo without the generalized lymphocytosis observed with high dosages of JJ316. Single i.v. administration of a low dose of the CD28 superagonist into Dark Agouti (DA) rats or Lewis rats that suffered from experimental autoimmune encephalomyelitis (EAE) proved to be highly and equally efficacious as high-dose treatment. Finally, we show that T reg cells that were isolated from CD28-treated animals displayed enhanced suppressive activity toward myelin basic protein-specific T cells in vitro, and, upon adoptive transfer, protected recipients from EAE. Our data indicate that this class of CD28-specific monoclonal antibodies targets CD4+CD25+ T reg cells and provides a novel means for the effective treatment of multiple sclerosis and other autoimmune diseases.  相似文献   
3.
4.
5.
6.
Described as asymptomatic and an incidental finding on a plain x-ray film, the “pelvic digit” is a rare congenital anomaly. A 35-year-old man is of a rare symptomatic pelvic digit that warranted surgical excision. Its importance lies in its differentiation from acquired abnormalities due to trauma such as myositis ossificans and avulsion injuries of pelvis. If this entity is kept in mind, unnecessary investigations or interventions can be avoided.  相似文献   
7.
Zusammenfassung Bei 65 Patienten mit Myasthenia gravis (MG) wurden Antikörper gegen Acetylcholin-Receptoren (ACh-R) in der IgG-Fraktion des Patienten-Serums bestimmt (Immunpräzipitations-Assay mit125Jod--Bungarotoxin und menschlichem ACh-R als Antigen). Bei 91% der Patienten zeigte sich eine erhöhte Antikörper-Konzentration bis zum 500fachen des oberen Referenzbereichs. Eine Kontrollgruppe von 77 Patienten mit anderen gesicherten Autoimmunerkrankungen oder positiven Antikörpern gegen Muskulatur wies in keinem Fall erhöhte ACh-R-Antikörper-Konzentrationen auf. Damit ist der in-vitro Nachweis von ACh-R-Antikörpern ein empfindlicher und hochspezifischer Test für die Diagnostik der MG. Der Test eignet sich ebenfalls für die Verlaufskontrolle unter Therapie mit Immunsuppressiva oder Plasmapherese. Immunfluoreszenz-Untersuchung auf Antikörper gegen Muskelgewebe ist für die MG-Diagnostik weniger empfindlich und nicht spezifisch.Herrn Prof. Dr. A. Struppler zum 60. Geburtstag gewidmet  相似文献   
8.
Molecular imaging requires, not only the identification of an appropriate marker, but also its quantitative analysis. We used the Sensitive Particle Acoustic Quantification (SPAQ) technology - a novel ultrasound technique - for detection and quantification of cell adhesion molecules in isolated tissue and in live animals. By conjugating gas-filled microparticles (MPs) with antibodies to intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1), we were able to depict and quantify ICAM-1 and VCAM-1 in isolated brain and spinal cord from rats with autoimmune encephalomyelitis (EAE), an established inflammatory disease model of human multiple sclerosis (MS). Depiction and quantification of specific MPs were also feasible in living animals with AT-EAE with similar results. After treatment with methylprednisolone, the measured number of targeted anti-ICAM-1 and VCAM-1-MPs was significantly lower (P<0.01) compared to untreated animals demonstrating the high sensitivity of this imaging technique. Depending on the antibody linked to the surface of the MPs, the technique can be used to quantify the expression of any accessible antigen expressed on the luminal surface of endothelial cells and is therefore a promising tool for the non-invasive and dynamic assessment of disease-related molecules.  相似文献   
9.
Autoimmune helper T lymphocytes were selected from the blood of two myasthenic patients of different HLA-DR type, using acetylcholine receptor (AChR) from Torpedo californica. These polyclonal T cell lines were tested for reactivity with three synthetic peptides corresponding to the NH2-terminal region of the human AChR alpha subunit. This segment is a good candidate for T cell epitopes since it has a propensity to form an amphipathic alpha helix. The peptides elicited 10-30% of the response induced by native Torpedo AChR. Different peptides were recognized by the autoreactive T cells of the two patients. These results suggest that the NH2-terminal region of the AChR alpha chain contains T cell-stimulating epitopes, and that the T cell autoimmune response in myasthenia gravis, like the B cell response, is heterogeneous.  相似文献   
10.
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