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Surface denaturation kinetics of different classes of crystallins have been studied by monolayer technique at air-NaCl solution interfaces. An increase of the conformation stability puts in the following order: pre-alpha < alpha approximately equal to beta H approximately equal to beta L approximately equal to gamma. 相似文献
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VI Chukanov 《Canadian Metallurgical Quarterly》1997,(4):17-19
The paper presents the current approaches to chemotherapy in patients with pulmonary tuberculosis and shows the main reasons that do not allow one to achieve high outcomes of treatment. These involve the drug resistance of Mycobacterium tuberculosis, the morphological features of a specific process in the lung, the higher incidence of acutely progressive types of pulmonary tuberculosis in particular; tuberculosis-contaminant diseases (diabetes mellitus, gastrointestinal, hepatic, renal diseases, and non-specific respiratory diseases, etc.). Recommendations how to eliminate the reasons for ineffective treatment of pulmonary tuberculosis are given. 相似文献
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VI Novoselov IV Peshenko VA Evdokimov SS Kamzalov SV Novoselov IuV Nikolaev MF Bystrova EE Fesenko 《Canadian Metallurgical Quarterly》1998,43(4):610-616
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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