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1.
On 11 May 1985 the main stand of Bradford City Football Club caught fire. Within four minutes the stand was alight from end to end. Fifty three people were burnt to death and about 250 injured; 83 required admission to hospital, and 55 of these were treated by primary excision of their burns and skin grafting. In such disasters the help of staff from other hospitals and areas is essential. Patients should be assessed to see whether they have burns that will ultimately be fatal; if they have they should not be sent to regional burns units, where they would take up beds that could be used for patients with treatable burns. All districts should ensure that their plans for accidents in which burns injuries predominate are adequate.  相似文献   
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Leukosialin is one of the major glycoproteins of thymocytes and T lymphocytes and is notable for a very high content of O-linked carbohydrate structures. The full protein sequence for rat leukosialin as translated from cDNA clones is now reported. The molecule contains 371 amino acids with 224 residues outside the cell, one transmembrane sequence and 124 cytoplasmic residues. Data from the peptide sequence and carbohydrate composition suggest that one in three of the extracellular amino acids may be O-glycosylated with no N-linked glycosylation sites. The cDNA sequence contained a CpG rich region in the 3' coding sequence and a large 3' non-coding region which included tandem repeats of the sequence GGAT.  相似文献   
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A study is made of the effect of GSH as a co-antioxidant with vitamin E during free radical chain autoxidation inhibition studies of dilinoleoylphosphatidylcholine (DLPC) liposomes. Oxidations are initiated in the aqueous phase with azobis(2-amidinopropane hydrochloride) and in the bilayer phase of DLPC with azobis(2,4-dimethylvaleronitrile) under known conditions of the rate of free radical chain initiation (Ri). In reactions initiated in the aqueous phase, GSH is not an efficient antioxidant when acting alone; however, in cooperation with vitamin E in the bilayers, it does effect significant extensions of the efficient induction period of vitamin E. Quantitative studies show that GSH "spares" 0.4 molecules of vitamin E in the bilayer/molecule of GSH and therefore terminates approximately 0.8 peroxyl radical chains as a co-antioxidant with vitamin E. In contrast, GSH is not an effective co-antioxidant with an efficient water-soluble antioxidant, 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylate (Trolox). GSH spares only 0.08 molecules of Trolox/molecule of GSH during autoxidation initiated in the aqueous phase with azobis(2-amidinopropane hydrochloride). The inhibition rate constant for GSH in trapping aqueous phase peroxyls is at least an order of magnitude less than that of Trolox. When peroxidation is initiated in the bilayer phase of DLPC with azobis(2,4-dimethylvaleronitrile), GSH is not an effective co-antioxidant with either vitamin E in the bilayer or Trolox in the water. Comparatively higher ratios of GSH to E (GSH/E = 50) or Trolox (GSH/Trolox = 30) are required to give significant extensions of the E or Trolox induction periods. GSH is estimated to preserve only approximately one vitamin E or Trolox molecule for a hundred GSH for peroxidations initiated in the DLPC bilayers. From the kinetic studies and GSH decay studies during inhibition periods, it is concluded that GSH does not act synergistically by regenerating ArOH from the phenoxyl, ArO, radical of vitamin E or Trolox. The mode of antioxidant action of GSH is concluded to be that of trapping peroxyl radicals in the aqueous phase and thereby indirectly sparing vitamin E in the bilayer.  相似文献   
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Methods were devised to purify the cell-associated, iron-binding compounds known as mycobactins from the closely related species Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium scrofulaceum (i.e., the MAIS complex of organisms). The mycobactins from these three species showed a structure that is common to the mycobactins from all the mycobacteria examined to date. However, these mycobactins were unique in that they had more than one alkyl chain. The M. scrofulaceum mycobactins differed from other MAIS mycobactins by a shift in the position of the double bond in the R1 alkyl chain. Traces of other mycobactin types were observed in ethanol extracts of the three species, and examination of the chromatographic properties of these mycobactins showed that each species produced five mycobactin types. Each mycobactin could be subdivided further by the length of its R1 alkyl chain. No differences in the production of these novel mycobactin were observed among species. Mycobactins from three strains of Mycobacterium paratuberculosis and two wood pigeon strains of Mycobacterium avium which had lost their original growth requirements for mycobactin after repeated subculturing in laboratory growth media were examined by thin-layer chromatography and high-pressure liquid chromatography. Each organism produced a mycobactin with similar chromatographic properties to those synthesized by MAIS organisms. M. paratuberculosis NADC 18 produced at least two components in our laboratory, and nuclear magnetic resonance analysis of the major component showed this mycobactin to be identical to that produced by M. intracellulare M12. However, a sample of mycobactin J isolated by Merkal and McCullough (Curr. Microbiol. 7:333-335, 1982) from M. paratuberculosis NADC 18 was different from our isolates and appeared to correspond to a minor mycobactin component we had seen by thin-layer chromatography. No reason for this difference could be evinced. Our findings indicate that there is a close taxonomic relationship between M. paratuberculosis and the MAIS complex.  相似文献   
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The leukocyte-common antigen (L-CA or T200) includes a family of lymphoid and myeloid cell surface glycoproteins with apparent molecular weights from 180,000 to 240,000. We report a partial protein sequence for thymocyte L-CA containing 1073 amino acids predicted from cDNA clones isolated using an oligonucleotide probe. Only one segment (residues 347-368) is likely to cross the membrane, and peptide data suggest that sequences N-terminal to this are outside the cell, with residues 369-1073 inside. The cytoplasmic domain includes possible phosphorylation sites and an internal homology between residues 385-671 and 676-986. Analysis of B lymphocyte cDNA clones suggests that B cell and thymocyte mRNAs are identical in 3' sequences, but size differences in Northern blots suggest 5' sequences may differ.  相似文献   
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The thermal polymerization of orosomucoid   总被引:1,自引:1,他引:0       下载免费PDF全文
1. Orosomucoid was prepared from the urine of a nephrotic patient and polymerized by heating it in a range of salt concentrations at pH4·1. 2. Heating at low ionic strengths produced a `chain' polymer of indefinite length but having the same width as the diameter of the monomer (5·0nm.). Similar treatment in high ionic strengths also produced a spherical (`ball') polymer of limited diameter (14·8nm.). 3. The size and shape of both polymers were determined from ultra-centrifuge, gel-filtration and electron-microscope results. The results suggest that eight monomer units condense to form the ball polymer. 4. Heating orosomucoid at pH1·8 hydrolysed the N-acetylneuraminic acid off the molecule; only chains could then be formed, even in high ionic strengths. 5. Both polymers were stable under normal conditions but could be depolymerized in 3m-guanidine hydrochloride. The monomer could be repolymerized on heating: the `chain monomer' only formed chains at all ionic strengths, but the `ball monomer' was indistinguishable from the original monomer in its immunological properties and polymerization reaction.  相似文献   
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