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91.
本文针对水电工程建设的特点,阐明了应用模糊系统多目标决策理论进行水电工程规划设计的依据,提供了水电工程决策系统综合指标体系分层递阶结构图,建立了适用于水电工程各类项目和各种主要参数方案评价选择的综合数学模型,以及使用该模型的方法,并给出了通用软件.此外,对权重的确定与修正、单指标评价技术等问题,根据大量资料分析研究和对各种类型决策问题的实例验证,提出了新的方法. 相似文献
92.
Eleonora Dondossola Anna Gasparri Angela Bachi Renato Longhi Marie-Hélène Metz-Boutigue Bruno Tota Karen B. Helle Flavio Curnis Angelo Corti 《Cellular and molecular life sciences : CMLS》2010,67(12):2107-2118
Fibroblast adhesion can be modulated by proteins released by neuroendocrine cells and neurons, such as chromogranin A (CgA)
and its N-terminal fragment vasostatin-1 (VS-1, CgA1–78). We have investigated the mechanisms of the interaction of VS-1 with fibroblasts and of its pro-adhesive activity and have
found that the proadhesive activity of VS-1 relies on its interaction with the fibroblast membrane via a phospholipid-binding
amphipathic α-helix located within residues 47–66, as well as on the interaction of the adjacent C-terminal region 67–78,
which is structurally similar to ezrin–radixin–moesin-binding phosphoprotein 50 (a membrane-cytoskeleton adapter protein),
with other cellular components critical for the regulation of cell cytoskeleton. 相似文献
93.
94.
Infantile-onset symptomatic epilepsy syndrome caused by a homozygous loss-of-function mutation of GM3 synthase 总被引:8,自引:0,他引:8
Simpson MA Cross H Proukakis C Priestman DA Neville DC Reinkensmeier G Wang H Wiznitzer M Gurtz K Verganelaki A Pryde A Patton MA Dwek RA Butters TD Platt FM Crosby AH 《Nature genetics》2004,36(11):1225-1229
We identified an autosomal recessive infantile-onset symptomatic epilepsy syndrome associated with developmental stagnation and blindness. Assuming a founder effect in a large Old Order Amish pedigree, we carried out a genome-wide screen for linkage and identified a single region of homozygosity on chromosome 2p12-p11.2 spanning 5.1 cM (maximum lod score of 6.84). We sequenced genes in the region and identified a nonsense mutation in SIAT9, which is predicted to result in the premature termination of the GM3 synthase enzyme (also called lactosylceramide alpha-2,3 sialyltransferase). GM3 synthase is a member of the sialyltransferase family and catalyzes the initial step in the biosynthesis of most complex gangliosides from lactosylceramide. Biochemical analysis of plasma glycosphingolipids confirmed that affected individuals lack GM3 synthase activity, as marked by a complete lack of GM3 ganglioside and its biosynthetic derivatives and an increase in lactosylceramide and its alternative derivatives. Although the relationship between defects in ganglioside catabolism and a range of lysosomal storage diseases is well documented, this is the first report, to our knowledge, of a disruption of ganglioside biosynthesis associated with human disease. 相似文献
95.
The spindle assembly checkpoint guards against chromosomal missegregation but does not induce arrest in oocytes that contain a few achiasmatic chromosomes (univalents). We followed the fate of univalents in oocytes during the first meiotic division, and although these preserved a meiotic kinetochore structure, they were also bi-oriented in a mitotic manner. The hybrid chromosomal configuration attained by univalents allows them to evade the spindle assembly checkpoint and contribute to aneuploidy in oocytes. 相似文献
96.
Gain-of-function RAF1 mutations cause Noonan and LEOPARD syndromes with hypertrophic cardiomyopathy 总被引:14,自引:0,他引:14
Pandit B Sarkozy A Pennacchio LA Carta C Oishi K Martinelli S Pogna EA Schackwitz W Ustaszewska A Landstrom A Bos JM Ommen SR Esposito G Lepri F Faul C Mundel P López Siguero JP Tenconi R Selicorni A Rossi C Mazzanti L Torrente I Marino B Digilio MC Zampino G Ackerman MJ Dallapiccola B Tartaglia M Gelb BD 《Nature genetics》2007,39(8):1007-1012
Noonan and LEOPARD syndromes are developmental disorders with overlapping features, including cardiac abnormalities, short stature and facial dysmorphia. Increased RAS signaling owing to PTPN11, SOS1 and KRAS mutations causes approximately 60% of Noonan syndrome cases, and PTPN11 mutations cause 90% of LEOPARD syndrome cases. Here, we report that 18 of 231 individuals with Noonan syndrome without known mutations (corresponding to 3% of all affected individuals) and two of six individuals with LEOPARD syndrome without PTPN11 mutations have missense mutations in RAF1, which encodes a serine-threonine kinase that activates MEK1 and MEK2. Most mutations altered a motif flanking Ser259, a residue critical for autoinhibition of RAF1 through 14-3-3 binding. Of 19 subjects with a RAF1 mutation in two hotspots, 18 (or 95%) showed hypertrophic cardiomyopathy (HCM), compared with the 18% prevalence of HCM among individuals with Noonan syndrome in general. Ectopically expressed RAF1 mutants from the two HCM hotspots had increased kinase activity and enhanced ERK activation, whereas non-HCM-associated mutants were kinase impaired. Our findings further implicate increased RAS signaling in pathological cardiomyocyte hypertrophy. 相似文献
97.
Mutations in the gene encoding the 3'-5' DNA exonuclease TREX1 are associated with systemic lupus erythematosus 总被引:1,自引:0,他引:1
Lee-Kirsch MA Gong M Chowdhury D Senenko L Engel K Lee YA de Silva U Bailey SL Witte T Vyse TJ Kere J Pfeiffer C Harvey S Wong A Koskenmies S Hummel O Rohde K Schmidt RE Dominiczak AF Gahr M Hollis T Perrino FW Lieberman J Hübner N 《Nature genetics》2007,39(9):1065-1067
TREX1 acts in concert with the SET complex in granzyme A-mediated apoptosis, and mutations in TREX1 cause Aicardi-Goutières syndrome and familial chilblain lupus. Here, we report monoallelic frameshift or missense mutations and one 3' UTR variant of TREX1 present in 9/417 individuals with systemic lupus erythematosus but absent in 1,712 controls (P = 4.1 x 10(-7)). We demonstrate that two mutant TREX1 alleles alter subcellular targeting. Our findings implicate TREX1 in the pathogenesis of SLE. 相似文献
98.
DMP1 mutations in autosomal recessive hypophosphatemia implicate a bone matrix protein in the regulation of phosphate homeostasis 总被引:14,自引:0,他引:14
Lorenz-Depiereux B Bastepe M Benet-Pagès A Amyere M Wagenstaller J Müller-Barth U Badenhoop K Kaiser SM Rittmaster RS Shlossberg AH Olivares JL Loris C Ramos FJ Glorieux F Vikkula M Jüppner H Strom TM 《Nature genetics》2006,38(11):1248-1250
Hypophosphatemia is a genetically heterogeneous disease. Here, we mapped an autosomal recessive form (designated ARHP) to chromosome 4q21 and identified homozygous mutations in DMP1 (dentin matrix protein 1), which encodes a non-collagenous bone matrix protein expressed in osteoblasts and osteocytes. Intact plasma levels of the phosphaturic protein FGF23 were clearly elevated in two of four affected individuals, providing a possible explanation for the phosphaturia and inappropriately normal 1,25(OH)2D levels and suggesting that DMP1 may regulate FGF23 expression. 相似文献
99.
Helgadottir A Manolescu A Helgason A Thorleifsson G Thorsteinsdottir U Gudbjartsson DF Gretarsdottir S Magnusson KP Gudmundsson G Hicks A Jonsson T Grant SF Sainz J O'Brien SJ Sveinbjornsdottir S Valdimarsson EM Matthiasson SE Levey AI Abramson JL Reilly MP Vaccarino V Wolfe ML Gudnason V Quyyumi AA Topol EJ Rader DJ Thorgeirsson G Gulcher JR Hakonarson H Kong A Stefansson K 《Nature genetics》2006,38(1):68-74
Variants of the gene ALOX5AP (also known as FLAP) encoding arachidonate 5-lipoxygenase activating protein are known to be associated with risk of myocardial infarction. Here we show that a haplotype (HapK) spanning the LTA4H gene encoding leukotriene A4 hydrolase, a protein in the same biochemical pathway as ALOX5AP, confers modest risk of myocardial infarction in an Icelandic cohort. Measurements of leukotriene B4 (LTB4) production suggest that this risk is mediated through upregulation of the leukotriene pathway. Three cohorts from the United States also show that HapK confers a modest relative risk (1.16) in European Americans, but it confers a threefold larger risk in African Americans. About 27% of the European American controls carried at least one copy of HapK, as compared with only 6% of African American controls. Our analyses indicate that HapK is very rare in Africa and that its occurrence in African Americans is due to European admixture. Interactions with other genetic or environmental risk factors that are more common in African Americans are likely to account for the greater relative risk conferred by HapK in this group. 相似文献
100.
Rivas MA Beaudoin M Gardet A Stevens C Sharma Y Zhang CK Boucher G Ripke S Ellinghaus D Burtt N Fennell T Kirby A Latiano A Goyette P Green T Halfvarson J Haritunians T Korn JM Kuruvilla F Lagacé C Neale B Lo KS Schumm P Törkvist L;National Institute of Diabetes Digestive Kidney Diseases Inflammatory Bowel Disease Genetics Consortium 《Nature genetics》2011,43(11):1066-1073
More than 1,000 susceptibility loci have been identified through genome-wide association studies (GWAS) of common variants; however, the specific genes and full allelic spectrum of causal variants underlying these findings have not yet been defined. Here we used pooled next-generation sequencing to study 56 genes from regions associated with Crohn's disease in 350 cases and 350 controls. Through follow-up genotyping of 70 rare and low-frequency protein-altering variants in nine independent case-control series (16,054 Crohn's disease cases, 12,153 ulcerative colitis cases and 17,575 healthy controls), we identified four additional independent risk factors in NOD2, two additional protective variants in IL23R, a highly significant association with a protective splice variant in CARD9 (P < 1 × 10(-16), odds ratio ≈ 0.29) and additional associations with coding variants in IL18RAP, CUL2, C1orf106, PTPN22 and MUC19. We extend the results of successful GWAS by identifying new, rare and probably functional variants that could aid functional experiments and predictive models. 相似文献