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101.
We developed a novel approach for the high-level production of a microbial transglutaminase (TGase) from Streptoverticillium in E. coli. The direct expression of the TGase gene in E. coli cells did not cause overproduction, probably due to the harmful influence of TGase activity, which introduces covalent crosslinks between proteins. Therefore, we fused the chemically synthesized TGase gene coding for the entire 331 amino acid residues at the amino terminus to a bacteriophage T7 gene 10 leader peptide (260 amino acids) using an inducible expression vector. The TGase gene was expressed as inclusion bodies in the E. coli cytoplasm. Restoring 15 amino acid residues upstream of the amino terminus of the mature TGase by a two-step deletion of the fusion sequence facilitated solubilization and subsequent proteolytic cleavage, thus releasing mature TGase. Although the mature form had less TGase activity than native TGase, because of the poor refolding rate, these results suggest that this system is suitable for the efficient production of TGase. 相似文献
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Experience of vascular thrombosis prophylaxis and treatment after reconstructive operation conduction on abdominal aorta and peripheral arteries in 244 patients, including 112 of them immediately after the operation, 32-up to one year time, 100-in long-term follow-up period was summarized. Main aetiological cause for thrombosis occurrence immediately after the operation were technical and tactical failures committed during its conduction, in the early postoperative period-the neointima hyperplasia in the anastomosis area, in late terms-the blood outflow disorder from the reconstructed segment due to the atherosclerosis progression. Original methods of reoperation conduction for the transplant thrombosis and the outflow arteries reconstruction were proposed. Mortality lowering from 8.8 to 5.3% and the extremity revascularization occurrence, in 75% of patients immediately after the operation and in 84%-in long-term period was promoted owing to tactics of postoperative thrombosis treatment elaborated. 相似文献
104.
AP Andonopoulos M Tiniakou M Melachrinou H Sfountouris A Bounas C Zervas NC Zoumbos 《Canadian Metallurgical Quarterly》1997,64(5):287-292
A prfA gene encoding polypeptide release factor RF1 was cloned from Thermus thermophilus. T thermophilus RF1 shares 68% homology with Escherichia coli RF1, and its overproduction reduced readthrough translation of UAG, not of UGA, in the lacZ gene. Rapid purification of T thermophilus RF1 was achieved by T7-RNA polymerase driven overexpression of T thermophilus RF1 protein with a C-terminal histidine tag. 相似文献
105.
NR Every LS Parsons SD Fihn EB Larson C Maynard AP Hallstrom JS Martin WD Weaver 《Canadian Metallurgical Quarterly》1997,96(6):1770-1775
BACKGROUND: Previous studies have documented the strong association between availability of on-site cardiac catheterization facilities and increased use of coronary angiography in patients with acute myocardial infarction (AMI). Although these studies have shown little influence of the availability of catheterization labs on hospital mortality, no long-term follow-up has been reported. METHODS AND RESULTS: From a cohort of 12,331 AMI patients admitted to 19 Seattle area hospitals, we compared long-term outcome in 7985 patients admitted to hospitals with and 4346 patients admitted to hospitals without on-site catheterization labs. During the index hospitalization, patients admitted to hospitals with on-site catheterization were more likely to undergo coronary angiography (67.1% versus 39.3%, P<.0001), coronary angioplasty (32.5% versus 13.2%, P<.0001), or coronary bypass surgery (12.5% versus 9.5%, P<.0001). At 3-year follow-up, patients admitted to hospitals with on-site catheterization labs were more likely to undergo postdischarge angiography (19.2% versus 15.2%, P=.0001) and coronary angioplasty (11.6% versus 8.2%, P<.0001). This was associated with approximately $2500.00 per patient in higher cumulative costs. Despite this higher rate of procedure use, there was no association between admission to a hospital with on-site catheterization facilities and lower long-term mortality (multivariate hazard ratio, 1.0; 95% CI, 0.93 to 1.1., the hazard being associated with admission to hospitals with on-site catheterization facilities). CONCLUSIONS: In an urban area with unconstrained patient transfer mechanisms and high overall cardiac procedure use rates, AMI patients admitted to hospitals without on-site catheterization facilities were managed with fewer procedures during hospitalization and follow-up. This more conservative treatment approach was not associated with any observed increase in long-term mortality. 相似文献
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