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131.
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Cystic fibrosis (CF) is the most common lethal autosomal recessive disorder among Caucasians and is caused by abnormalities in the cystic fibrosis transmembrane conductance regulator gene (CFTR). CFTR gene encodes a chloride channel that regulates secretion in many exocrine tissues especially pancreatic and pulmonary tissues. The clinical presentation of cystic fibrosis is highly variable with isolated CAVD (congenital absence of vas deferens) and/or typical pancreatic and pulmonary manifestations. Over 500 mutations in the CFTR gene have been described and vary among different geographic locations. The severity of clinical manifestations and specially the pulmonary disease is poorly correlated with genotype. It is interesting to collect clinical and genetical data by analysing a larger cohort of CF patients. These results are likely to improve our understanding of the physiopathology of CF and the genetic counselling; particular biochemical defect could lead to more specific treatments in the future. From our 110 patients selected in Champagne-Ardenne country, we analysed the entire coding sequence of CFTR gene and detected 95% of CF mutations and in fact, 89.5% if we include the CAVD patients; 59.4% of CF mutations were detected for these patients. Three new mutations have been here reported. We found numerous CF mutations with a large distribution throughout the gene. Nevertheless, three exons are mainly involved: 10, 11 and 21. Relationships between the genotype and phenotype are difficult to assess. 相似文献
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J Barreto J Liljestrand C Palha de Sousa S Bergstr?m B B?ttiger G Biberfeld F De la Cruz 《Canadian Metallurgical Quarterly》1993,25(6):685-688
The seroprevalence of HIV-1 and HIV-2 among pregnant women in Maputo, the capital of Mozambique, was compared between the years 1982/83, 1988 and 1990. None of the 432 serum samples collected in 1982/83 was positive for HIV antibodies whereas in 1988 the HIV-1 and HIV-2 seroprevalence was 0.4% (2/500) and 0.6% (3/500), respectively, and in 1990 0.6% (12/2014) and 0.2% (4/2014), respectively. These results indicate that HIV infection has been introduced recently in Maputo and is spreading at a slow rate among women. 相似文献
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F Devlieghere B De Meulenaer P Sekitoleko AA Estrella Garcia A Huyghebaert 《Canadian Metallurgical Quarterly》1997,14(6-7):671-683
In this study several types of bottle materials (glass, PET (polyethylene terephthalate), PC (polycarbonate), HDPE (high density polyethylene), PP (polypropylene) and PVC (polyvinyl chloride)) were evaluated in order to be used as food refillables, comparing the residual chemical contamination after classical caustic washing. Bottles were contaminated with model chemicals (chloroxylenol and d-limonene) and caustic washed with varied process parameters using a simulated laboratory-scale washing procedure. After washing, the chemical-contaminated bottles were filled with water and stored for 28 days at 37 degrees C. The concentrations of the model chemicals in the water after storage were taken as a measure of chemical contamination. The influence of the cleaning parameters (temperature, caustic and commercial additive concentration) was studied using response surface methodology. Washing temperature showed a significant influence on the removal of absorbed chemicals from surfaces compared with the effect of the caustic and especially the additive concentration. Optimization of caustic cleaning for the cleaning process in question led to better cleaning effectiveness, although none of the different washing conditions were able to remove all absorbed chemicals out of the polymeric resins. Commercially available plastic refillables (PET and PC) showed the best chemical rinsability. Glass bottles, however, had in every case the best rinsing characteristics. 相似文献
138.
A method of posterior mitral annulus remodeling is presented. The posterior annulus is divided into three segments, each segment encircled by a suture that is passed in a tourniquet. Coaptation of the leaflets can be achieved by tightening the tourniquets while the ventricle is being filled. This technique is simple and quick, avoids the use of foreign material, and requires less expertise and judgment than traditional annuloplasties. 相似文献
139.
D. J. Strike N. F. De Rooij M. Koudelka-Hep M. Ulmann J. Augustynski 《Journal of Applied Electrochemistry》1992,22(10):922-926
The oxidation of methanol on gold electrodes modified with polypyrrole and platinum is reported. These electrodes were characterized by cyclic voltammetry and by 12h polarizations in methanol solutions. They were found to give higher currents and lower rates of drift than electrodes of platinum and platinized gold. The effect of varying the amount of platinum deposited is also discussed. 相似文献
140.