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471.
Japanese goshawk was classified as a vulnerable species in the Red Data Book. There have been possibilities of a decrease of genetic diversity accompanied by habitat loss and genetic pollution due to hybridization with escaping imported goshawks. In this paper, genetic diversity, gene flow and conservation of Northern Goshawk (Accipiter gentilis) in Japan are discussed and compared with that in Central Asia. We used 11 newly developed microsatellite markers and also adopted six previously published markers. Genetic diversity was shown to be maintained with 0.58 as mean heterozygosity and 3.95 as mean allelic richness. The degree of genetic differentiation across all populations was low (Nei’s genetic differentiation index = 0.036, Wright’s genetic differentiation index = 0.039), possibly due to gene flow via adjacent regions (average number of migrants = 4.26; 0.68–20.30). However, it is possible that slight differentiation resulted from the short divergence time and/or inflow of escaping imported individuals. We recommend that goshawks in eastern Japan should be managed as a single unit. They do not appear to be under threat genetically at present, but there is the potential for rapid loss of genetic diversity. For future conservation, investigations of dispersal routes and actual conditions of gene flow are also recommended. To prevent further inflow of escaping goshawks into natural populations, it is desirable to reduce importation of goshawks and to enact a regulation obliging purchasers to register imported goshawks. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
472.

Background  

The use of knowledge-based potential function is a powerful method for protein structure evaluation. A variety of formulations that evaluate single or multiple structural features of proteins have been developed and studied. The performance of functions is often evaluated by discrimination ability using decoy structures of target proteins. A function that can evaluate coarse-grained structures is advantageous from many aspects, such as relatively easy generation and manipulation of model structures; however, the reduction of structural representation is often accompanied by degradation of the structure discrimination performance.  相似文献   
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Renal tubular dysplasia is a hereditary disease of Japanese black cattle showing renal failure and growth retardation with an autosomal recessive trait. In the present study, we mapped the locus responsible for the disease (RTD) by linkage analysis with an inbred paternal half-sib pedigree obtained from commercial herds. By analyzing segregation of microsatellite markers in the half-sibs, significant linkage was observed between the RTD locus and markers on bovine Chromosome (Chr) 1 with the highest lod score of 11.4. Homozygosity mapping with the inbred pedigree further defined the localization of the RTD locus in a 4-cM region between microsatellite markers BMS4003 and INRA119. Mapping of the RTD locus on bovine Chr 1 will facilitate cloning and characterization of the gene responsible for this disease. Received: 24 September 1999 / Accepted: 14 December 1999  相似文献   
476.
Patients presenting with functional somatic syndrome (FSS) are common, and the symptoms are persistent and difficult to treat for doctors and costly for society. The aim of this study was to clarify the common pathophysiology of FSS, especially the relationship between hypothalamic-pituitary-adrenal (HPA) axis function and psychological characteristics of patients with FSS. The subjects were 45 patients with FSS and 29 healthy controls. Salivary free cortisol was measured in the morning, and psychological tests examining depression, anxiety and quality of life (QOL) were performed on the same day. In patients with FSS, depressive scores showed a significant negative correlation with salivary free cortisol in the morning, although in healthy controls, cortisol showed a significant positive correlation with depressive scores. In addition, the correlation between other psychological test scores and cortisol secretion in patients with FSS contrasted with that of controls. The relationship between cortisol and depression, anxiety or QOL, suggests that the HPA axis of patients with FSS is dysfunctional and does not function properly when patients with FSS are under stress. This dysfunction may explain the pathology of medically unexplained persistent symptoms of patients with FSS.  相似文献   
477.
SAP155, a subunit of the U2 snRNP, is essential for prespliceosome assembly and splicing catalysis of the major spliceosome. Moreover, the protein has been identified in the minor (U12-dependent) spliceosome. These facts strongly suggest that SAP155 is shared by two distinct complexes owing to its importance in the removal of any type of intron. Here we have isolated a cDNA encoding the 146-kDa mouse homolog, designated Sf3b1. The amino acid sequence of Sf3b1 is very highly conserved among homologs from Schizosaccharomyces pombe (52.4% identity) to human (99.6%), and the C-terminal 825 residues of these Sf3b1 homologs show even higher identities. This C-terminal region shows significant similarity to the PR65 subunit of protein phosphatase 2A, which is composed of 15 tandem repeats of a 39 amino acid sequence. Mouse genome analyses showed Sf3b1 to be a single-copy gene mapping to the central part of Chromosome (Chr) 1. Northern blot analysis and whole mount in situ hybridization revealed Sf3b1 to be ubiquitously expressed in a variety of adult tissues and mid-gestation embryos. Received: 14 June 2000 / Accepted: 19 October 2000  相似文献   
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