全文获取类型
收费全文 | 116篇 |
免费 | 17篇 |
出版年
2022年 | 2篇 |
2020年 | 2篇 |
2019年 | 1篇 |
2017年 | 2篇 |
2016年 | 5篇 |
2015年 | 7篇 |
2014年 | 10篇 |
2013年 | 15篇 |
2012年 | 7篇 |
2011年 | 7篇 |
2010年 | 6篇 |
2009年 | 8篇 |
2008年 | 9篇 |
2007年 | 10篇 |
2006年 | 4篇 |
2005年 | 8篇 |
2004年 | 4篇 |
2003年 | 3篇 |
2002年 | 6篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1995年 | 2篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1975年 | 2篇 |
1974年 | 1篇 |
排序方式: 共有133条查询结果,搜索用时 15 毫秒
1.
Ludo Filez Willy Stalmans Freddy Penninkx Raymond Kerremans Karel Geboes 《Bioscience reports》1987,7(12):917-923
Lactate dehydrogenase has been measured in the small-intestinal mucosa in order to assess its value as a marker for the effects of ischemia and of reperfusion. The decrease in specific activity of the enzyme illustrates the deleterious effect of reperfusion on the quality of the remaining epithelial cells. However, this parameter fails to detect the loss of epithelial cells, which is the major event during ischemia as well as during reperfusion. In contrast, the expression of enzyme activity per g protein of the underlying intestinal muscle allowed us, in addition, to assess quantitatively the loss of epithelial cells, in good agreement with the histological data. 相似文献
2.
Using enzyme and immunohistochemical methods on whole-mount preparations and cryostat sections, a morphologic and semiquantitative study was performed of the nervous tissue in the appendix and the ileum (areas with and without Peyer's patches) of the rabbit. The plexus submucous externus (Meissner) consists of a network of small ganglia, vaguely associated with the vascular submucosal plexus. From the nerve cell bodies, cell processes occasionally penetrate the lymphoid follicles at the junction between the mucosa and the submucosa while other extensions form a dense plexus in the lamina propria of the mucosa. No nerve fibers are present in the dome of the follicles. The plexus submucous internus (Henle), consisting of large cell bodies and large processes, closely follows the blood vessels. The numeration of the nerve fibers of the submucosal plexus endorses the histological finding that the appendix is a richly innervated lymphoid organ. In addition, the plexus myentericus (Auerbach) of the appendix is a network of small meshes, while in the ileum, in the area of Peyer's patches, the same plexus is composed of a network with large meshes. These differences point to a higher density of innervation in the appendix. Yet a specialized anatomic distribution of the innervation of lymphoepithelial structures cannot be demonstrated. 相似文献
3.
Posttranslational regulation of nitrogenase in Rhodospirillum rubrum strains overexpressing the regulatory enzymes dinitrogenase reductase ADP-ribosyltransferase and dinitrogenase reductase activating glycohydrolase. 总被引:6,自引:5,他引:1 下载免费PDF全文
Rhodospirillum rubrum strains that overexpress the enzymes involved in posttranslational nitrogenase regulation, dinitrogenase reductase ADP-ribosyltransferase (DRAT) and dinitrogenase reductase activating glycohydrolase (DRAG), were constructed, and the effect of this overexpression on in vivo DRAT and DRAG regulation was investigated. Broad-host-range plasmid constructs containing a fusion of the R. rubrum nifH promoter and translation initiation sequences to the second codon of draT, the first gene of the dra operon, were constructed. Overexpression plasmid constructs which overexpressed (i) only functional DRAT, (ii) only functional DRAG and presumably the putative downstream open reading frame (ORF)-encoded protein, or (iii) all three proteins were generated and introduced into wild-type R. rubrum. Overexpression of DRAT still allowed proper regulation of nitrogenase activity, with ADP-ribosylation of dinitrogenase reductase by DRAT occurring only upon dark or ammonium stimuli, suggesting that DRAT is still regulated upon overexpression. However, overexpression of DRAG and the downstream ORF altered nitrogenase regulation such that dinitrogenase reductase did not accumulate in the ADP-ribosylated form under inactivation conditions, suggesting that DRAG was constitutively active and that therefore DRAG regulation is altered upon overexpression. Proper DRAG regulation was observed in a strain overexpressing DRAT, DRAG, and the downstream ORF, suggesting that a proper balance of DRAT and DRAG levels is required for proper DRAG regulation. 相似文献
4.
5.
6.
7.
Christine Breynaert Tom Dresselaers Clémentine Perrier Ingrid Arijs Jonathan Cremer Leentje Van Lommel Kristel Van Steen Marc Ferrante Frans Schuit Séverine Vermeire Paul Rutgeerts Uwe Himmelreich Jan L. Ceuppens Karel Geboes Gert Van Assche 《PloS one》2013,8(7)
Introduction
Chronically relapsing inflammation, tissue remodeling and fibrosis are hallmarks of inflammatory bowel diseases. The aim of this study was to investigate changes in connective tissue in a chronic murine model resulting from repeated cycles of dextran sodium sulphate (DSS) ingestion, to mimic the relapsing nature of the human disease.Materials and Methods
C57BL/6 mice were exposed to DSS in drinking water for 1 week, followed by a recovery phase of 2 weeks. This cycle of exposure was repeated for up to 3 times (9 weeks in total). Colonic inflammation, fibrosis, extracellular matrix proteins and colonic gene expression were studied. In vivo MRI T 2 relaxometry was studied as a potential non-invasive imaging tool to evaluate bowel wall inflammation and fibrosis.Results
Repeated cycles of DSS resulted in a relapsing and remitting disease course, which induced a chronic segmental, transmural colitis after 2 and 3 cycles of DSS with clear induction of fibrosis and remodeling of the muscular layer. Tenascin expression mirrored its expression in Crohn’s colitis. Microarray data identified a gene expression profile different in chronic colitis from that in acute colitis. Additional recovery was associated with upregulation of unique genes, in particular keratins, pointing to activation of molecular pathways for healing and repair. In vivo MRI T2 relaxometry of the colon showed a clear shift towards higher T2 values in the acute stage and a gradual regression of T2 values with increasing cycles of DSS.Conclusions
Repeated cycles of DSS exposure induce fibrosis and connective tissue changes with typical features, as occurring in Crohn’s disease. Colonic gene expression analysis revealed unique expression profiles in chronic colitis compared to acute colitis and after additional recovery, pointing to potential new targets to intervene with the induction of fibrosis. In vivo T2 relaxometry is a promising non-invasive assessment of inflammation and fibrosis. 相似文献8.
Lies Boelen Patrick K. O’Neill Kathryn J. Quigley Catherine J. Reynolds Bernard Maillere John H. Robinson Ganjana Lertmemongkolchai Daniel M. Altmann Rosemary J. Boyton Becca Asquith 《PLoS computational biology》2016,12(3)
Activation of CD4+ T cells requires the recognition of peptides that are presented by HLA class II molecules and can be assessed experimentally using the ELISpot assay. However, even given an individual’s HLA class II genotype, identifying which class II molecule is responsible for a positive ELISpot response to a given peptide is not trivial. The two main difficulties are the number of HLA class II molecules that can potentially be formed in a single individual (3–14) and the lack of clear peptide binding motifs for class II molecules. Here, we present a Bayesian framework to interpret ELISpot data (BIITE: Bayesian Immunogenicity Inference Tool for ELISpot); specifically BIITE identifies which HLA-II:peptide combination(s) are immunogenic based on cohort ELISpot data. We apply BIITE to two ELISpot datasets and explore the expected performance using simulations. We show this method can reach high accuracies, depending on the cohort size and the success rate of the ELISpot assay within the cohort. 相似文献
9.
Joke Duyck Katleen Vandamme Stefanie Krausch-Hofmann Lies Boon Katrien De Keersmaecker Eline Jalon Wim Teughels 《PloS one》2016,11(1)