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Recombinant horseradish peroxidase reactivated from E. coli inclusion bodies was studied in a reversed micellar system of AOT in octane. The ability of the recombinant enzyme, in contrast to native horseradish peroxidase, to form a dimeric structure was found. The existence of the dimer was proved by results of sedimentation analysis. Dimer/monomer ratio in the enzyme-containing micelles and dimer catalytic activity were found to depend on the substrate used (pyrogallol, guaiacol, o-dianisidine, o-phenylenediamine). Computer modelling was used to describe possible structures of the dimeric recombinant horseradish peroxidase.  相似文献   
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BACKGROUND: Percutaneous mitral valvuloplasty with the Inoue balloon is conventionally performed with double vascular access: arterial and venous. However, in patients with a good echogenic window it may be performed with venous access only and the procedure monitored by 2D-echocardiography and colour flow mapping. This should result in early ambulation and hospital discharge with reduced arterial complications. AIMS: To compare retrospectively the immediate results of percutaneous mitral valvuloplasty with the Inoue balloon in two groups of patients: Group I: venous access only (no arterial access, n = 102) and Group II: conventional double vascular access (arterial and venous access, n = 275). METHODS AND RESULTS: The baseline characteristics of the two groups were comparable for age, sex, clinical, echocardiographic, radiological and haemodynamic variables. The mitral valve area (Group I: 1.1 +/- 0.3 to 1.85 +/- 0.5 cm2 vs Group II: 1.05 +/- 0.2 to 1.85 +/- 0.5 cm2, P = ns) and transmitral gradient (Group I: 11 +/- 4 to 4.7 +/- 2 mmHg vs Group II: 12 +/- 4 to 4.8 +/- 2 mmHg, P = ns) before and after mitral valvuloplasty were not statistically different. A good immediate result, defined as mitral valve area > 1.5 cm2 and mean mitral gradient < 5 mmHg with mitral regurgitation < or = 2+ at the end of the procedure, was observed in 77% of the cases in the venous-only group and 79% in the double access group (P = ns). The incidence of severe mitral regurgitation (Grade III or IV) was not statistically significant. Procedural duration (71 +/- 24 min vs 109 +/- 26 min, P < 0.01), fluoroscopic time (12.5 +/- 5.5 min vs 18.5 +/- 6 min, P < 0.01) and hospital stay (2.8 +/- 1.5 days vs 4.8 +/- 2.6 days, P < 0.001) were significantly shorter in the venous-only group than in the conventional Inoue series. CONCLUSION: Single venous access balloon mitral valvuloplasty is as equally safe and effective as double vascular access. The additional advantages of single venous access are shorter procedural duration, fluoroscopic time and hospital stay. We recommend that it be performed by an experienced operator (minimum of 100 trans-septal punctures) in patients without major thoracic deformity and a good echogenic window.  相似文献   
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The effect of alpha-tocopherol and its derivatives on viability and growth of attached cells culture: human epithelioid carcinoma of cervix HeLa-S3K and human cervical carcinoma cell line C-4-1 according to protein content and level of alkaline phosphatase, as well to unattached cells: human acute leukemia cell cultures CEM-C-1 and CEM-C-7 according to the amount of viable cells in suspension has been studied. It has been shown that alpha-tocopherol acetate and tocopherol maintain the viability of cells, while the derivatives of tocopherol with shorted side chain considerably inhibit growth of researched cultures, alpha-tocopherol with lacking side chain being most active among them.  相似文献   
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