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901.
Repression of the Escherichia coli modABCD (molybdate transport) operon by ModE. 总被引:5,自引:1,他引:4 下载免费PDF全文
A M Grunden R M Ray J K Rosentel F G Healy K T Shanmugam 《Journal of bacteriology》1996,178(3):735-744
902.
903.
Clinicians rely heavily on expert based systems-consultation with colleagues, journal reviews and textbooks, and continuing education activities-to obtain new information. The usefulness of sources such as these depends on the relevance and validity of the information and the work it takes to obtain it. Useful information can be distinguished from the useless by asking three questions: Does the information focus on an outcome that my patients care about? Is the issue common to my practice, and is the intervention feasible? If the information is true, will it require me to change my practice? If the answer to all three questions is yes, then the information is a common POEM (patient oriented evidence that matters), capable of improving the lives of your patients and must be evaluated for validity. Conclusions based on results of well designed clinical trials are more likely to be valid than those drawn from observations based on experience in clinical practice. Both members of the team, clinicians and experts, must take responsibility for their respective roles. 相似文献
904.
The synthesis, translocation, and decarboxylation of phosphatidylserine can occur in a cell-free system (Voelker, D. R. (1989) J. Biol. Chem. 264, 8019-8025). We made use of the spatial separation of the site of biosynthesis and the site of decarboxylation of phosphatidylserine to demonstrate that mitochondrial contact sites are intimately involved in the translocation of phosphatidylserine prior to decarboxylation. In that sense, the inhibition of phosphatidylserine decarboxylase leads to an accumulation of this phospholipid in the contact site-enriched fractions without mixing the inner membrane phospholipid pool. On the other hand, newly synthesized phosphatidylethanolamine can be exported very rapidly to the mitochondrial surface in the same way, i.e. via contact sites. These data provide further evidence for the existence of a structural and functional microcompartmentation at the inner mitochondrial membrane surface. 相似文献
905.
The rate of proteolysis is an important determinant of the intracellular protein content. Part of the degradation of intracellular
proteins occurs in the lysosomes and is mediated by macroautophagy. In liver, macroautophagy is very active and almost completely
accounts for starvation-induced proteolysis. Factors inhibiting this process include amino acids, cell swelling and insulin.
In the mechanisms controlling macroautophagy, protein phosphorylation plays an important role. Activation of a signal transduction
pathway, ultimately leading to phosphorylation of ribosomal protein S6, accompanies inhibition of macroautophagy. Components
of this pathway may include a heterotrimeric Gi3-protein, phosphatidylinositol 3- kinase and p70S6 kinase. Recent evidence
indicates that lysosomal protein degradation can be selective and occurs via ubiquitin- dependent and -independent pathways.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
906.
907.
F. Vardar-Sukan 《Biotechnology letters》1991,13(2):107-112
The foam collapse and foam formation properties of four different simulated fermentation media were compared in the presence and absence of natural oils. It was found that optimum effective natural oil concentration resulting in optimum foam suppression did not always correspond with the optimum for foam collapse, nor the optimum for maximum foam collapse rate. 相似文献
908.
A method based on the infection of CaCo-2 cells and molecular hybridization with a specific cDNA probe has been developed for the detection of infectious astroviruses in environmental samples. By this procedure wild-type astroviruses have been detected in water from an area where a concurrent gastroenteritis outbreak was reported. 相似文献
909.
910.
Reintroducing the European Beaver to Britain: nostalgic meddling or restoring biodiversity? 总被引:1,自引:0,他引:1
The European Beaver Castor fiber once occurred throughout Europe, but in many countries was exterminated or greatly reduced by over-hunting. In the UK, Beavers were last recorded in Scotland in the sixteenth century. Thirteen countries have carried out reintroduction programmes to restore the range of the Beaver in Europe, We provide a basis for discussing the feasibility and desirability of reintroducing the Beaver to Britain. The basic biology of the Beaver is described, followed by summaries of reintroductions in Europe and an evaluation of their successes and failures. We address the fundamental questions of propagule size, habitat requirements, habitat size and provenance of Beavers to be released, before examining in theory whether reintroducing Beavers to Britain is likely to fulfil UKCINC and IUCN criteria relating to environmental impact, socioeconomics and conservation. We then make suggestions as to how a reintroduction to Britain could proceed. Essential work outstanding includes site assessment and public consultation. The restoration of the Beaver to Britain could be a fitting start to the millennium. 相似文献