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排序方式: 共有993条查询结果,搜索用时 15 毫秒
981.
Dr. Ed. Formánek 《Plant Systematics and Evolution》1885,35(4):119-121
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982.
Ed de Jong Evelien E. Beuling Rick P. van der Zwan Jan A. M. de Bont 《Applied microbiology and biotechnology》1990,34(3):420-425
Summary Several bacteria, yeast and fungi selectively isolated from paper-mill waste-water grew on veratryl alcohol, a key intermediate of lignin metabolism. Penicillium simplicissimum oxidized veratryl alcohol via a NAD(P)+-dependent veratryl alcohol dehydrogenase to veratraldehyde, which was further oxidized to veratric acid in a NAD(P)+-dependent reaction. Veratric-acid-grown cells contained NAD(P)H-dependent O-demethylase activity for veratrate, vanillate and isovanillate. Protocatechuate was cleaved by a protocatechuate 3,4-dioxygenase.
Offprint requests to: E. de Jong 相似文献
983.
Dr. Ed. Formánek 《Plant Systematics and Evolution》1885,35(10):355-357
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984.
Dr. Ed. Formánek 《Plant Systematics and Evolution》1885,35(10):345-346
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985.
Carol Kilkenny Nick Parsons Ed Kadyszewski Michael F. W. Festing Innes C. Cuthill Derek Fry Jane Hutton Douglas G. Altman 《PloS one》2009,4(11)
For scientific, ethical and economic reasons, experiments involving animals should be appropriately designed, correctly analysed and transparently reported. This increases the scientific validity of the results, and maximises the knowledge gained from each experiment. A minimum amount of relevant information must be included in scientific publications to ensure that the methods and results of a study can be reviewed, analysed and repeated. Omitting essential information can raise scientific and ethical concerns. We report the findings of a systematic survey of reporting, experimental design and statistical analysis in published biomedical research using laboratory animals. Medline and EMBASE were searched for studies reporting research on live rats, mice and non-human primates carried out in UK and US publicly funded research establishments. Detailed information was collected from 271 publications, about the objective or hypothesis of the study, the number, sex, age and/or weight of animals used, and experimental and statistical methods. Only 59% of the studies stated the hypothesis or objective of the study and the number and characteristics of the animals used. Appropriate and efficient experimental design is a critical component of high-quality science. Most of the papers surveyed did not use randomisation (87%) or blinding (86%), to reduce bias in animal selection and outcome assessment. Only 70% of the publications that used statistical methods described their methods and presented the results with a measure of error or variability. This survey has identified a number of issues that need to be addressed in order to improve experimental design and reporting in publications describing research using animals. Scientific publication is a powerful and important source of information; the authors of scientific publications therefore have a responsibility to describe their methods and results comprehensively, accurately and transparently, and peer reviewers and journal editors share the responsibility to ensure that published studies fulfil these criteria. 相似文献
986.
Dr. Ed. Formánek 《Plant Systematics and Evolution》1885,35(11):386-388
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987.
Ron D.M. Soede Yvonne M. Wijnands Ioana Van Kouteren-Cobzaru Ed Roos 《The Journal of cell biology》1998,142(5):1371-1379
The ZAP-70 tyrosine kinase is essential for T cell activation by the T cell receptor. We show that ZAP-70 is also required for migration of T cells that is dependent on the integrin LFA-1. Invasion of TAM2D2 T cell hybridoma cells into fibroblast monolayers, which is LFA-1–dependent, was blocked by overexpression of dominant-negative ZAP-70 and by piceatannol but not by herbimycin A. The Syk inhibitor piceatannol blocks the Syk homologue ZAP-70, which is expressed by TAM2D2 cells, with the same dose dependence as the inhibition of invasion. Dominant-negative ZAP-70 completely inhibited the extensive metastasis formation of TAM2D2 cells to multiple organs upon i.v. injection into mice. Migration of TAM2D2 cells through filters coated with the LFA-1 ligand ICAM-1, induced by 1 ng/ml of the chemokine SDF-1, was blocked by anti–LFA-1 mAb and also abrogated by dominant-negative ZAP-70 and piceatannol. In contrast, migration induced by 100 ng/ml SDF-1 was independent of both LFA-1 and ZAP-70. LFA-1 cross-linking induced tyrosine phosphorylation, which was blocked by dominant-negative ZAP-70 and piceatannol. We conclude that LFA-1 engagement triggers ZAP-70 activity that is essential for LFA-1–dependent migration. 相似文献
988.
989.
990.
Dr. Ed. Formánek 《Plant Systematics and Evolution》1885,35(8):265-270
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