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Bicarbon valve - European multicenter clinical evaluation   总被引:1,自引:0,他引:1  
Objective: Fifteen collaborating centers in eight countries present their pooled experience with the new Bicarbon™ bileaflet valve. Methods: Between 4/90 and 4/96, 1351 patients, 806 males and 545 females, aged 10 to 83, mean 58.4±12.4, underwent valve implantation. Operations: AVR, 726; MVR, 475; DVR, 150. Additional procedures: CABG, 211; TV repair, 64; other, 152. Results: Mortality: 67 early (seven valve related) and 56 late (40 valve related). Valve thrombosis: six obstructive, three non-obstructive; embolism: nine major cerebral, 37 other. Major bleeding: 29. Hemolysis: two clinically significant. Non-structural dysfunction: 24 paravalvular leaks, one leaflet interference. No structural failure! Endocarditis: 24. Reoperation 48: 22 non-structural dysfunctions, 14 endocarditis, seven thrombosis and embolism, five other. Estimated 5-year freedom from valve-related deaths is 97.2% for AVR and 92.4% for MVR; 4-year freedom from valve related deaths for DVR is 90.5%. Mean calculated NYHA improvement is 1.24. Conclusions: The Bicarbon mechanical prosthesis is well designed, durable, has good hemodynamic features and an acceptably low incidence of complications.  相似文献   
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Progesterone exerts on the central nervous system a number of effects, some of which are estrogen dependent mostly in the preoptic area and the mediobasal hypothalamus. In these regions, an immunocytochemical study was used to evaluate differences in progesterone receptor (PR) immunoreactivity between the male and the female guinea pig in response to 10 μg/day estradiol benzoate (EB) for 5 consecutive days. Compared to EB-treated females, EB-treated males showed a slightly lower number of PR-immunoreactive cells in the preoptic area whereas PR-immunoreactivity appeared in more cells in the anterior part of the ventrolateral nucleus. The numbers of PR-immunoreactive cells in the arcuate nucleus did not differ significantly between males and females. These results show that regionally localized sex differences exist in the induced PR system after 5 days exposure to EB.  相似文献   
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The biological activity carried by the carboxy-terminal domain of SV40 large T antigen has been investigated by isolating mutants deleted for a stretch of six acidic residues which by analogy with polyoma middle T antigen might be essential for the activity of the protein. We have constructed an "in-phase" deletion of 37 residues that includes the complete acid residues cluster. In order to parallel the polyoma hr-t mutants genotype, the deletion was introduced in virus strains either competent or defective for the small t antigen. We conclude from these experiments that the deletion of this unusual sequence does not affect per se any of the known biological properties of the virus.  相似文献   
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To determine the extent to which the vagina, endocervix, and amniotic fluid screen the Escherichia coli strains responsible for neonatal infections, we studied the genetic relationships among 105 E. coli strains isolated from all of the ecosystems involved in this infectious process. Twenty-four strains were isolated from the intestinal flora, and 25 strains were isolated from the vaginas of pregnant women. Twenty-seven strains were isolated from the amniotic fluid, blood, and cerebrospinal fluid (CSF) of infected neonates. The intraspecies genetic characteristics of all of the isolates were determined by random amplified polymorphic DNA (RAPD) analysis, PCR ECOR (E. coli reference) grouping, and PCR virulence genotyping. A correlation was found between the intraspecies distributions of the strains in the A, B1, B2, and D ECOR groups and in the two major RAPD groups (I and II). Nevertheless, the distribution of the E. coli strains in the RAPD groups according to their anatomical origins was more significant than their distribution in the ECOR groups. This may be explained by the existence of an E. coli subpopulation, defined by the RAPD I group, within the ECOR B2 group. This RAPD I group presents a major risk for neonates: 75% of the strains isolated from patients with meningitis and 100% of the strains isolated from patients with bacteremia were in this group. The vagina and the amniotic fluid are two barriers that favor colonization by highly infectious strains. Indeed, only 17% of fecal strains belonged to the RAPD I group, whereas 52% of vaginal strains and 67% of amniotic fluid strains belonged to this subpopulation. The ibeA and iucC genes were significantly associated with CSF strains, whereas the hly and sfa/foc genes were more frequent in blood strains. These findings could serve as a basis for developing tools to recognize vaginal strains, which present a high risk for neonates, for use in prophylaxis programs.  相似文献   
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Two patients with Ph-positive chronic myelocytic leukemia in erythroblastic transformation and rearrangement of the short arm of chromosome 18 are reported. Fluorescence in situ hybridization studies showed that the 18p rearrangement resulted from translocation of the main part of chromosome 22 long arm to 18p, including BCR-ABL1 fusion. The 18p abnormality resulted, thus, in loss of 18p and duplication of BCR-ABL1 in both patients. The possible relation to the erythroblastic type of blastic phase is briefly discussed. In addition an apparently intact germline ABL1 gene was duplicated and inserted into chromosome 6 at band p21 in one of these patients.  相似文献   
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It was shown that radical polymerization of butadiene in 1-butanol and 2-butanol, initiated by hydrogen peroxide cleaved into two hydroxyl radicals by heat, leads to three types of polymers according to their respective polydispersity. It was found that the formation of these products — oligomers, polymers, and high polymers — can be influenced by modifying the experimental conditions. Thus, it is possible to obtain selectively oligomers free of polymers and polymers free of low molecular weight oligomers.  相似文献   
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Fluorescence in situ hybridization analysis was carried out in five patients with acute myeloblastic leukemia of various French-American-British subtypes and with double trisomy of chromosomes 8 and 21. PML-RARA fusion was detected with appropriate molecular probes in one patient with acute promyelocytic leukemia without t(15;17). Two PAC probes covering the 5' and 3' part of the RUNX1 gene were used in the four other patients. While three copies were present in three patients, as expected from conventional karyotype analysis, only two hybridization signals were present in the fifth patient. This was due to the apparent loss of the 3' part of RUNX1. Since chromosome number abnormalities may be associated with submicroscopic gene rearrangements, it should be important to search for them for a better understanding of mechanisms of leukemogenesis, and to understand the prognostic heterogeneity in leukemic patients with aneusomies without apparent chromosome structure rearrangements.  相似文献   
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The pathogeny of ulcerative colitis (UC) is not yet elucidated, but some arguments suggest the implication of genetic factors. Among the candidate genes, those encoding for HLA class II genotypes have been extensively studied in UC; however, discordant data may be imputable to heterogeneity, characterized by immunological markers such as atypical ANCA (p-ANCA), or to inclusion of more or less intractable UC. The aim of our study is to evaluate the interest of HLA class II and TAP genetic markers to identify different clinical forms of UC, according to p-ANCA status. Unrelated patients with a history of UC (n=91) and healthy control subjects with no personal or family history of inflammatory bowel diseases (IBD) (n=200) were included. HLA-DRB103 was less frequent in UC patients than in healthy controls (8% vs 28%,PC<0.03). No association was found with any TAP genotypes. Moreover, there was no association with the HLA-DR2 specificity, either in the entire group of UC patients (38% vs 28%) or in the p-ANCA-positive subgroup of patients (30%). The most consistent finding in the present study is that some genetic markers may characterize intractability in UC patients. HLA-DR2 was associated with poor prognosis, regardless of p-ANCA status. In HLA-DR2 and non-HLA-DR2 groups, colectomy was done in 55% and 27% of patients, respectively (PC<0.05). Furthermore, in non-HLA-DR2 patients, p-ANCA could be of interest to characterize those with more severe prognosis. Our results confirm the interest of genetic studies to define UC genetic susceptibility, taking into account intractability of the disease. They do not support the hypothesis that p-ANCA is a subclinical marker of genetic susceptibility to UC.  相似文献   
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