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The article deals with the results of complex study of the effect of pulmonary insufficiency on intracardiac hemodynamics and function of the heart in the immediate and late-term periods after radical correction of Fallot's tetralogy. Answers are also given to questions concerning the expediency of the use and functional adequacy of a xeno-pericardial monocusp in the closure mechanism of the pulmonary artery valve. The study showed that massive pulmonary regurgitation has a negative effect on the functional condition of the right ventricle in late-term postoperative periods. Convincing data were obtained which allow a graft with a monocusp of a bull's pericardium to be recommended for further clinical use to prevent insufficiency of the pulmonary artery valve after radical correction of Fallot's tetralogy.  相似文献   
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Cyclic peptide disulfides of the general formula were synthesized from the corresponding peptide derivatives [Boc-Cys(Trt)(Gly)-n-Cys(Trt)-OBut] by oxidation with iodine in methanol and by subsequent removal of the terminal groups with trifluoroacetic acid. Acid ionization constants of the obtained peptides were determined by potentiometric titration in aqueous KCl (0.1 mol/L) medium. All compounds have two dissociable hydrogens, corresponding to carboxyl (pK1= 2.35–2.84) and to terminal amino group (pK2= 5.61–6.93); pK1, values show first an upward and then a downward trend with the increase in ring size; the opposite is true for pK2, values. These trends could be tentatively attributed to the intramolecular salt bridge (-COO——-NH+3-) formation.  相似文献   
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GTP cyclohydrolase (GCH1) is rate limiting for tetrahydrobiopterin (BH4) synthesis, where BH4 is a cofactor for nitric oxide (NO) synthases and aromatic hydroxylases. GCH1 polymorphisms are implicated in the pathophysiology of pain, but have not been investigated in African populations. We examined GCH1 and pain in sickle cell anemia where GCH1 rs8007267 was a risk factor for pain crises in discovery (n = 228; odds ratio [OR] 2.26; P = 0.009) and replication (n = 513; OR 2.23; P = 0.004) cohorts. In vitro, cells from sickle cell anemia subjects homozygous for the risk allele produced higher BH4. In vivo physiological studies of traits likely to be modulated by GCH1 showed rs8007267 is associated with altered endothelial dependent blood flow in females with SCA (8.42% of variation; P = 0.002). The GCH1 pain association is attributable to an African haplotype with where its sickle cell anemia pain association is limited to females (OR 2.69; 95% CI 1.21–5.94; P = 0.01) and has the opposite directional association described in Europeans independent of global admixture. The presence of a GCH1 haplotype with high BH4 in populations of African ancestry could explain the association of rs8007267 with sickle cell anemia pain crises. The vascular effects of GCH1 and BH4 may also have broader implications for cardiovascular disease in populations of African ancestry. Am. J. Hematol. 89:187–193, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
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Summary Three cases of criss-cross heart with severe and complex congenital defects are reported. Precise preoperative diagnosis of the morphologic abnormalities made it possible to choose an optimal method of surgical treatment: all patients successfully underwent a Fontantype surgical procedure.  相似文献   
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