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71.
72.
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
73.
74.
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
75.
76.
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
77.
A. Witvrouw K. Maex W. De Ceuninck G. Lekens J. D'Haen L. De Schepper 《Microelectronics Reliability》1998,38(6-8)
The degradation due to stress induced voiding of nitride passivated Al-1 wt.% Si and Ti/TN/ Al-1wt.% Si-0.5 wt. % Cu/Ti/TN interconnects with widths ranging between 0.4 and 1.2 μm was studied by in-situ conventional
high resolution resistance measurements (HRRM) during storage at temperatures between 168 and 240°C. The conventional measurements on Al-Si lines, which lasted more than one year, clearly showed that the interconnect lifetime decreases with decreasing line width. With HRRM the degradation due to stress induced voiding can be detected much sooner and with much more detail. From the HRRM it is clear that the resistance changes during storage often happen in jumps and that the degradation has a rather complex alloy, line width and temperature dependence. Both for 0.4 and 0.6 μm wide Al---Si lines more degradation occurred for storage at 175 °C compared to storage at 200 °C. For the Al---Si---Cu stacks the degradation of 0.4 μm wide lines was worse for storage at 240°C compared to storage at 200 °C, but the opposite was true for the 0.6 μm wide lines. 相似文献
78.
Balasa F. Catthoor F. Hugo De Man 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》1995,3(2):157-172
Memory cost is responsible for a large amount of the chip and/or board area of customized video and image processing system realizations. In this paper, we present a novel technique-founded on data-flow analysis which allows one to address the problem of background memory size evaluation for a given nonprocedural algorithm specification, operating on multidimensional signals with affine indexes. Most of the target applications are characterized by a huge number of signals, so a new polyhedral data-flow model operating on groups of scalar signals is proposed. These groups are obtained by a novel analytical partitioning technique, allowing to select a desired granularity, depending on the application complexity. The method incorporates a way to tradeoff memory size with computational and controller complexity 相似文献
79.
Pb1–x
Ca
x
[(Co0.5W0.5)0·05Ti0.95]O3 ceramics with x = 0.24, 0.30 and 0.35, are prepared by a solid state reaction of oxides. Deviations from nominal chemical compositions and formation of segregated phases different from modified lead titanate perovskites, are studied. Pyro- and non-pyroelectric currents excited in the material by a thermal wave are investigated and related to mobility of electrical charges in the materials. 相似文献
80.
The conclusions are put forward that are adopted by a discussion group preparing the framework for a limitation policy of the radon problem in Belgium. Existing and future situations are treated in a coherent policy that is adequate for practical implementation. An action level is defined, together with a hierachy of levels for new constructions. The decision logic for the acceptance of building materials is explained. 相似文献