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1.
Austin A. Robinson Kevin Ikuta Jonathan Soverow 《The Yale journal of biology and medicine》2014,87(2):199-206
Few prospective studies support the use of anticoagulation during the acute phase of ischemic stroke, though observational data suggest a role in certain populations. Depending on the mechanism of stroke, systemic anticoagulation may prevent recurrent cerebral infarction, but concomitantly carries a risk of hemorrhagic transformation. In this article, we describe a case where anticoagulation shows promise for ischemic stroke and review the evidence that has discredited its use in some circumstances while showing its potential in others. 相似文献
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D C Knipple L L Payne D M Soderlund 《Archives of insect biochemistry and physiology》1991,16(1):45-53
A segment of the house fly (Musca domestica) homologue of the para (paralytic) sodium channel gene of Drosophila melanogaster was isolated by using mixed sequence oligonucleotide primers in the polymerase chain reaction (PCR). The specificity of the procedure was demonstrated by genomic Southern analysis using the housefly PCR amplification product as a probe and by DNA sequence analysis. The latter showed structural homology to the para gene, but not to the corresponding region of DSC1, another D. melanogaster gene with structural similarity to vertebrate sodium channel genes. 相似文献
3.
Expression of tetanus toxin fragment C in yeast: gene synthesis is required to eliminate fortuitous polyadenylation sites in AT-rich DNA. 总被引:6,自引:1,他引:5 下载免费PDF全文
M A Romanos A J Makoff N F Fairweather K M Beesley D E Slater F B Rayment M M Payne J J Clare 《Nucleic acids research》1991,19(7):1461-1467
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Abstract Four isolates of the non-motile species Aeromonas media , icluding the type strain, were demonstrated by transmission electronk microcopy to possess polar flagella. Motility appeared to be restricted to old, regularly subcultured strains, and coincided with an increase in colony size and a concomitant reduction in the amount of brown diffusible pigment produced by colonies on tryptone soya agar. 相似文献
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R. C. Spike J. McGadey H. S. Johnston A. P. Payne G. G. Thompson M. R. Moore 《The Histochemical journal》1986,18(5):245-250
Summary The rodent Harderian gland is an important site of porphyrin biosynthesis and storage. Porphyrins are visible at the light and electron microscope level as large intraluminal accretions, as large interstitial accretions surrounded by foreign body giant cells, or as small interstitial deposits within free macrophages. Since porphyrins are soluble in a wide range of solvents, it is important to employ histological routines which minimize porphyrin loss during processing in addition to giving good tissue preservation. In this quantitative investigation, these requirements were optimally achieved with fixation in 3% buffered glutaraldehyde and the use of amyl acetate as a clearing agent. 相似文献
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Abstract— Colchichine blocks axoplasmic flow of proteins in chicken sciatic nerve. The slow component is more effectively blocked than the fast. The colchicine effect on slow flow is independent of the time delay between colchicine injection and that of the [14 C]-leucine used to measure flow, over a period extending from 2 h after to 9 days before the leucine. It is still effective, but to a lesser degree, after a period of 27 days. There is little effect on the fast component when the colchicine is administered after leucine. When given before leucine the effect is not pronounced up to a time interval of 1 day. Maximum blockage was obtained with longer intervals of up to 27 days. These results are discussed in relation to the involvement of the microtubules in both slow flow and rapid flow.
The effect of both cytochalasins A and B on slow and rapid protein flow has also been studied. Neither drug had any significant effect on slow flow. Cytochalasin A reduced the amount of protein flowing at the rapid rate to a small extent when administered 2 h before [14 C]leucine. Cytochalasin B also caused a similar reduction and this effect was independent of dose over the ranges of doses used. The cytochalasin B diminished the incorporation of amino acid into protein in the spinal cord and it has been concluded that these results are due to a membrane effect which reduces uptake of amino acid rather than a direct effect on neurofilaments in the axons. 相似文献
The effect of both cytochalasins A and B on slow and rapid protein flow has also been studied. Neither drug had any significant effect on slow flow. Cytochalasin A reduced the amount of protein flowing at the rapid rate to a small extent when administered 2 h before [
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A new method for selecting RNA polymerase mutants 总被引:12,自引:0,他引:12