全文获取类型
收费全文 | 2693374篇 |
免费 | 190799篇 |
国内免费 | 5855篇 |
专业分类
耳鼻咽喉 | 37713篇 |
儿科学 | 86597篇 |
妇产科学 | 75998篇 |
基础医学 | 381134篇 |
口腔科学 | 79875篇 |
临床医学 | 237702篇 |
内科学 | 521496篇 |
皮肤病学 | 61146篇 |
神经病学 | 211110篇 |
特种医学 | 103280篇 |
外国民族医学 | 659篇 |
外科学 | 410268篇 |
综合类 | 62909篇 |
现状与发展 | 10篇 |
一般理论 | 926篇 |
预防医学 | 196532篇 |
眼科学 | 65048篇 |
药学 | 199510篇 |
11篇 | |
中国医学 | 6430篇 |
肿瘤学 | 151674篇 |
出版年
2018年 | 27998篇 |
2017年 | 21614篇 |
2016年 | 23963篇 |
2015年 | 27193篇 |
2014年 | 37964篇 |
2013年 | 56526篇 |
2012年 | 76606篇 |
2011年 | 81014篇 |
2010年 | 48122篇 |
2009年 | 45464篇 |
2008年 | 76078篇 |
2007年 | 82034篇 |
2006年 | 82637篇 |
2005年 | 79474篇 |
2004年 | 77070篇 |
2003年 | 73829篇 |
2002年 | 71820篇 |
2001年 | 131542篇 |
2000年 | 134701篇 |
1999年 | 112692篇 |
1998年 | 30500篇 |
1997年 | 27227篇 |
1996年 | 26701篇 |
1995年 | 25500篇 |
1994年 | 23523篇 |
1993年 | 21902篇 |
1992年 | 86476篇 |
1991年 | 84050篇 |
1990年 | 81527篇 |
1989年 | 78884篇 |
1988年 | 72508篇 |
1987年 | 71285篇 |
1986年 | 67679篇 |
1985年 | 64315篇 |
1984年 | 47938篇 |
1983年 | 40854篇 |
1982年 | 23822篇 |
1981年 | 21512篇 |
1979年 | 44458篇 |
1978年 | 31278篇 |
1977年 | 26859篇 |
1976年 | 24639篇 |
1975年 | 27183篇 |
1974年 | 32563篇 |
1973年 | 31603篇 |
1972年 | 29817篇 |
1971年 | 27791篇 |
1970年 | 26093篇 |
1969年 | 24731篇 |
1968年 | 23244篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
H.M. Evans 《Canadian Medical Association journal》2005,172(5):667-668
992.
993.
Guerard W. Byrne Johannes M. Schirmer David N. Fass Sumeet S. Teotia Walter K. Kremers Hui Xu Bashoo Naziruddin Henry D. Tazelaar John S. Logan Christopher G. A. McGregor 《American journal of transplantation》2005,5(5):1011-1020
Microvascular thrombosis is a prominent feature in cardiac delayed xenograft rejection (DXR). We investigated the impact of warfarin or low-molecular-weight heparin (LMWH) anti-coagulation on xenograft function using a heterotopic pig-to-primate model. Donor hearts were from CD46 transgenic pigs and baboon immunosuppression included tacrolimus, sirolimus, anti-CD20 and TPC, an alpha-galactosyl-polyethylene glycol conjugate. Three groups of animals were studied. Group 1 (n = 9) was treated with warfarin, Group 2 (n = 13) with LMWH and Group 3, received no anti-coagulant drugs. The median duration of xenograft function was 20 days (range 3-62 days), 18 days (range 5-109 days) and 15 days (range 4-53 days) in Groups 1 to 3 respectively. Anti-coagulation achieved the targeted international normalized prothrombin ratio (INR) and anti-factor Xa levels consistent with effective in vivo therapy yet, no significant impact on median xenograft function was observed. At rejection, a similar histology of thrombosis and ischemia was apparent in each group and the levels of fibrin deposition and platelet thrombi in rejected tissue was the same. Anti-coagulation with warfarin or LMWH did not have a significant impact on the onset of DXR and microvascular thrombosis. However, a role for specific anti-coagulant strategies to achieve long-term xenograft function cannot be excluded. 相似文献
994.
995.
Fady K. Baddoura Isam W. Nasr Barbara Wrobel Qi Li Nancy H. Ruddle Fadi G. Lakkis 《American journal of transplantation》2005,5(3):510-516
Lymphoid neogenesis is the process by which ectopic lymphoid accumulations that resemble lymph nodes arise in nonlymphoid tissues. Such lymphoid accumulations, known as tertiary lymphoid organs (TLO), are observed in chronic autoimmunity and they propagate immune pathology by setting up local antigen presenting sites. Whether lymphoid neogenesis occurs in transplanted organs and contributes to rejection is not well understood. To begin to address this question, we retrospectively analyzed 319 murine cardiac allografts for microscopic evidence of lymph-node-like structures. We found 78 allografts that had either classical TLO, characterized by discrete T- and B-cell zones and high endothelial venules (HEV) expressing peripheral node addressin (PNAd) (n = 34), or PNAd(+) HEV without organized lymphoid accumulations (n = 44). These changes were present in both short- and long-lived allografts and were invariably associated with rejection. Importantly, they occurred in 78% of allografts undergoing chronic rejection (n = 85) but in only 7% of allografts undergoing primarily acute rejection (n = 184). These findings indicate that, like autoimmunity, alloimmunity is associated with lymphoid neogenesis in the target organ and suggest a role for local T-cell activation in chronic allograft rejection. 相似文献
996.
U. Bolm-Audorff S. Brandenburg T. Brüning H. Dupuis R. Ellegast G. Elsner K. Franz H. Grasshoff V. Grosser L. Hanisch B. Hartmann E. Hartung K. G. Hering G. Heuchert M. Jäger J. Krämer Dr. A. Kranig E. Ludolph A. Luttmann A. Nienhaus W. Pieper K.-D. Pöhl T. Remé D. Riede G. Rompe K. Schäfer S. Schilling E. Schmitt F. Schröter A. Seidler M. Spallek M. Weber 《Trauma und Berufskrankheit》2005,7(3):211-252
Occupational diseases Nos. 2108 and 2110 correspond to intervertebral disc-related diseases of the lumbar spine from many years of carrying or lifting heavy loads, occupations in extreme postures of full flexion or oscillation of the whole body when seated, and which compel the cessation of all activities which are or could be the cause for the origin, exacerbation or recurrence of the disease. These occupational diseases came into force at the start of 1993, but there have been considerable problems in their implementation. The present Part I of the contribution is the result of the work of an interdisciplinary study group and contains medical criteria for the assessment of possibly strain-related clinical characteristics and the evaluation of other possible causes. Part II is to be published in Volume 4/2005 and will deal with questions related to forced cessation and to the assessment of the loss of earning ability. Agreement was reached in many areas related to the assessment of occupational claims. This should allow for evidence-based decision making in the future for the occupational diseases Nos. 2108 and 2110. 相似文献
997.
Michael Rosenzweig Martha Skinner Tatiana Prokaeva Roger Théberge Catherine Costello Brian M Drachman Lawreen H Connors 《Amyloid》2007,14(1):65-71
We report the identification of a new transthyretin (TTR) gene mutation and variant protein, Glu61Gly, in a 55-year-old man with progressive cardiomyopathy, mild peripheral neuropathy and bilateral carpal tunnel syndrome. A diagnosis of TTR-associated familial amyloidosis (ATTR) was considered after an endomyocardial biopsy revealed amyloid deposits in the heart of a patient who had no family history of amyloidosis and no evidence of a plasma cell dyscrasia. Serum screening for a TTR variant by isoelectric focusing (IEF) was positive and prompted further studies to identify the genetic abnormality and to characterize the amyloidogenic protein. Direct DNA sequence analysis of all four coding regions in the TTR gene demonstrated heterozygosity in exon 3. Near equal amounts of guanine (G) and adenine (A) were observed at the second base position of codon 61. The wild-type (GAG) and mutated (GGG) sequences found in codon 61 correspond to glutamic acid (Glu) and glycine (Gly) residues, amino acids which differ in mass by -72 Da. Mass spectrometric analyses of TTR immunoprecipitated from serum showed the presence of both wild-type and variant proteins. The observed mass results for the wild-type and variant proteins were consistent with the predicted values calculated from the genetic analysis data. 相似文献
998.
999.
1000.
The β‐adhesin part of the Porphyromonas gingivalis W50 (ATCC 53978) protease HRgpA was cloned in an eukaryotic expression vector and expressed in COS‐7 cells. The monoclonal antibody MAb (61BG1.3), specific for the hemagglutinating domain of β‐adhesin, recognized the expressed β‐adhesin in the transfected cells both by immunoblot and immunofluorescence. Sprague Dawley rats were immunized intramuscularly with β‐adhesin encoding expression plasmid and expression plasmid without β‐adhesin insert. Skeletal muscle tissue at the site of immunization in the β‐adhesin immunized animals was shown to express this protein. The immunization induced a β‐adhesin‐specific antibody response. Sera from the immunized animals were tested for hemagglutination inhibiting activity. Due to high natural inhibiting activity in all rat sera tested, no increased hemagglutination inhibition was detected in sera from the β‐adhesin immunized animals. 相似文献