全文获取类型
收费全文 | 2363篇 |
免费 | 138篇 |
国内免费 | 40篇 |
出版年
2023年 | 5篇 |
2022年 | 26篇 |
2021年 | 59篇 |
2020年 | 11篇 |
2018年 | 34篇 |
2017年 | 24篇 |
2016年 | 91篇 |
2015年 | 213篇 |
2014年 | 221篇 |
2013年 | 243篇 |
2012年 | 276篇 |
2011年 | 201篇 |
2010年 | 116篇 |
2009年 | 90篇 |
2008年 | 105篇 |
2007年 | 72篇 |
2006年 | 54篇 |
2005年 | 89篇 |
2004年 | 83篇 |
2003年 | 61篇 |
2002年 | 61篇 |
2001年 | 46篇 |
2000年 | 29篇 |
1999年 | 13篇 |
1998年 | 17篇 |
1997年 | 10篇 |
1996年 | 16篇 |
1995年 | 6篇 |
1994年 | 5篇 |
1993年 | 14篇 |
1992年 | 18篇 |
1991年 | 10篇 |
1990年 | 13篇 |
1989年 | 12篇 |
1988年 | 13篇 |
1987年 | 5篇 |
1986年 | 10篇 |
1985年 | 6篇 |
1983年 | 5篇 |
1982年 | 5篇 |
1978年 | 5篇 |
1974年 | 6篇 |
1973年 | 5篇 |
1972年 | 5篇 |
1968年 | 5篇 |
1962年 | 5篇 |
1957年 | 6篇 |
1951年 | 5篇 |
1947年 | 4篇 |
1926年 | 4篇 |
排序方式: 共有2541条查询结果,搜索用时 746 毫秒
101.
Bouchlaka C Othman TB Aissaoui L Elloumi H Elloumi M Amouri A Abid HB Hadiji S Slama H Makni H Saad A Abdelhak S Dellagi K;Tunisian Fanconi Anemia Study Group 《Genetic testing》2004,8(3):268-275
We report on the effectiveness of molecular studies regarding Fanconi anemia (FA) for a better selection of bone marrow graft donors and for post-transplant follow up. Ten unrelated FA patients and their families were analyzed by microsatellite markers. In 9 cases, the cytogenetic investigation of potential human leukocyte antigen (HLA)-identical related donors was normal, and the molecular analyses confirmed that they were also either normal or heterozygous carriers. For 1 patient, cytogenetic analysis of an HLA-identical sibling donor yielded ambiguous results with a relatively high number of chromosomal breakages using cross-linking agents. However, genotyping of this potential donor demonstrated his heterozygous state. Nine patients have received allogeneic bone marrow transplantation from HLA-matched related donors. Microsatellite analysis showed complete chimerism (CC) in all cases. The median follow up was 54 months (range 8-144 months). One patient out of 9 with CC rejected her graft without prior detection of a transitional mixed chimerism. Among these patients, 1 died 25 months after the transplantation of a chronic graft-versus-host-disease (GVHD). We conclude that, when the cytogenetic studies are not conclusive, molecular analyses are crucial to distinguish heterozygous carriers from asymptomatic FA Tunisian patients. Molecular analyses also allowed the evaluation of hematopoietic chimerism after allogeneic bone marrow transplantation and might be of value to identify patients with a high risk for graft rejection. 相似文献
102.
103.
104.
105.
Morton DB Hawkins P Bevan R Heath K Kirkwood J Pearce P Scott L Whelan G Webb A;British Veterinary Association Animal Welfare Foundation;Fund for Replacement of Animals in Medical Experiments;Royal Society for the Prevention of Cruelty to Animals;Universities Federation for Animal Welfare 《Laboratory animals》2003,37(4):261-299
106.
HLA-DR2 dose effect on susceptibility to multiple sclerosis and influence on disease course 总被引:7,自引:0,他引:7 下载免费PDF全文
Barcellos LF Oksenberg JR Begovich AB Martin ER Schmidt S Vittinghoff E Goodin DS Pelletier D Lincoln RR Bucher P Swerdlin A Pericak-Vance MA Haines JL Hauser SL;Multiple Sclerosis Genetics Group 《American journal of human genetics》2003,72(3):710-716
Models of disease susceptibility in multiple sclerosis (MS) often assume a dominant action for the HLA-DRB1*1501 allele and its associated haplotype (DRB1*1501-DQB1*0602 or DR2). A robust and phenotypically well-characterized MS data set was used to explore this model in more detail. A dose effect of HLA-DR2 haplotypes on MS susceptibility was revealed. This observation suggests that, in addition to the role of HLA-DR2 in MS, two copies of a susceptibility haplotype further increase disease risk. Second, we report that DR2 haplotypes modify disease expression. There is a paucity of benign MS and an increase of severe MS in individuals homozygous for DR2. Concepts of the molecular mechanisms that underlie linkage and association of the human leukocyte antigen (HLA) region to MS need to be revised to accommodate these data. 相似文献
107.
108.
109.
Transport and metabolism of dicarboxylates may be important in the glial-neuronal metabolic interplay. Further, exogenous dicarboxylates have been suggested as cerebral energy substrates. After intrastriatal injection of [(14) C]fumarate or [(14) C]malate, glutamine attained a specific activity 4.1 and 2.6 times higher than that of glutamate, respectively, indicating predominantly glial uptake of these four-carbon dicarboxylates. In contrast, the three-carbon dicarboxylate [(14) C]malonate gave a specific activity in glutamate which was approximately five times higher than that of glutamine, indicating neuronal uptake of malonate. Therefore, neurones and glia take up different types of dicarboxylates, probably by different transport mechanisms. Labelling of alanine from [(14) C]fumarate and [(14) C]malate demonstrated extensive malate decarboxylation, presumably in glia. Intravenous injection of 75 micromol [U-(13) C]fumarate rapidly led to high concentrations of [U-(13) C]fumarate and [U-(13) C]malate in serum, but neither substrate labelled cerebral metabolites as determined by (13) C NMR spectroscopy. Only after conversion of [U-(13) C]fumarate into serum glucose was there (13) C-labelling of cerebral metabolites, and only at <10% of that obtained with 75 micromol [3-(13) C]lactate or [2-(13) C]acetate. These findings suggest a very low transport capacity for four-carbon dicarboxylates across the blood-brain barrier and rule out a role for exogenous fumarate as a cerebral energy substrate. 相似文献
110.
Hartung T;Human 《Alternatives to laboratory animals : ATLA》2002,30(Z2):49-51
The Limulus amoebocyte lysate (LAL) test has replaced about 80% of the use of the rabbit pyrogen test. Ideally, human-based in vitro tests are needed, to replace the remaining use of the rabbit test and the use of the LAL test. The progress of an EU-funded project is described, in which a number of in vitro tests, based on the human fever reaction are passing through a prevalidation study on the way to evaluation in a formal validation study. 相似文献