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Amelogenesis imperfecta (AI) is a collective term used to describe phenotypically diverse forms of defective tooth enamel development. AI has been reported to exhibit a variety of inheritance patterns, and several loci have been identified that are associated with AI. We have performed a genome-wide scan in a large Brazilian family segregating an autosomal dominant form of AI and mapped a novel locus to 8q24.3. A maximum multipoint LOD score of 7.5 was obtained at marker D8S2334 (146,101,309 bp). The disease locus lies in a 1.9 cM (2.1 Mb) region according to the Rutgers Combined Linkage-Physical map, between a VNTR marker (at 143,988,705 bp) and the telomere (146,274,826 bp). Ten candidate genes were identified based on gene ontology and microarray-facilitated gene selection using the expression of murine orthologues in dental tissue, and examined for the presence of a mutation. However, no causative mutation was identified.  相似文献   
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The relationship between biodiversity and the activities of small-scale farmers remains poorly understood despite its importance for conservation. In tropical forest areas farmers often include extraction of forest products in their subsistence strategies, and it has been suggested that factors such as market access and diversity levels influence people’s use of forest products. To investigate these relationships, we studied the use of palms in five villages inhabited by colonists and indigenous Shuar in the lower montane forest in south-eastern Ecuador by means of interviews and line transects around the villages. We found that use of palms was not driven by the diversity of palms available in the forest surrounding each village. Instead, the most important factor seemed to be lack of market access so in villages furthest away from the nearest road people used more palm products for their subsistence life compared to villages closer to the road. Forests around more remote villages had higher utility levels when evaluated on the basis of the villagers’ use of palms, despite lower levels of palm diversity and richness in these forests. The lower diversity levels may reflect past human activity or ecological factors, or a combination of both. In either case, our results show that forests with higher diversity levels are not necessarily more valuable to local people compared to less diverse forests. Instead, socio-economic factors such as market access may be more important in shaping people’s relationship with the natural environment.  相似文献   
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Mäki  Mari  Aaltonen  Hermanni  Heinonsalo  Jussi  Hellén  Heidi  Pumpanen  Jukka  Bäck  Jaana 《Plant and Soil》2019,441(1-2):89-110
Plant and Soil - Vegetation emissions of volatile organic compounds (VOCs) are intensively studied world-wide, because oxidation products of VOCs contribute to atmospheric processes. The overall...  相似文献   
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Schizophrenia is a severe mental disorder affecting approximately 1% of the world's population. Here, we report the results from a three-stage genomewide screen performed in a study sample from an internal isolate of Finland. An effort was made to identify genes predisposing for schizophrenia that are potentially enriched in this isolate, which has an exceptionally high lifetime risk for this trait. Ancestors of the local families with schizophrenia were traced back to the foundation of the population in the 17th century. This genealogical information was used as the basis for the study strategy, which involved screening for alleles shared among affected individuals originating from common ancestors. We found four chromosomal regions with markers revealing pairwise LOD scores>1.0: 1q32.2-q41 (Z(max)=3.82, dominant affecteds-only model), 4q31 (Z(max)=2. 74, dominant 90%-penetrance model), 9q21 (Z(max)=1.95, dominant 90%-penetrance model), and Xp11.4-p11.3 (Z(max)=2.01, recessive 90%-penetrance model). This finding suggests that there are several putative loci predisposing to schizophrenia, even in this isolate.  相似文献   
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Nõges  Peeter  Tuvikene  Lea  Feldmann  Tõnu  Tõnno  Ilmar  Künnap  Helen  Luup  Helen  Salujõe  Jaana  Nõges  Tiina 《Hydrobiologia》2003,506(1-3):567-573
Hydrobiologia - The hydrochemical regime and the biota in two lakes of Vooremaa landscape protection area, Central Estonia, were studied in 2000–2001 within the frames of the EC project...  相似文献   
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ABSTRACT: BACKGROUND: Considerable evidence suggests that food impacts both the gastro-intestinal (GI) function and the microbial ecology of the canine GI tract. The aim of this study was to evaluate the influence of high-carbohydrate (HC), high-protein (HP) and dry commercial (DC) diets on the canine colonic microbiota in Beagle dogs. Diets were allocated according to the Graeco-Latin square design. For this purpose, microbial DNA was isolated from faecal samples and separated by density gradient centrifugation, resulting in specific profiling based on the guanine-cytosine content (%G+C). In addition, 16S rRNA gene amplicons were obtained from the most abundant %G+C peaks and analysed by sequence analysis, producing a total of 720 non-redundant sequences (240 sequences per diet). RESULTS: The DC diet sample showed high abundance of representatives of the orders Clostridiales, Lactobacillales, Coriobacteriales and Bacteroidales. Sequence diversity was highest for DC diet samples and included representatives of the orders Lactobacillales and Bacteroidales, which were not detected in samples from the HP and HC diets. These latter two diets also had reduced levels of representatives of the family Lachnospiraceae, specifically Clostridial cluster XIVa. The HC diet favoured representatives of the order Erysipelotrichales, more specifically the Clostridial cluster XVIII, while the HP diet favoured representatives of the order Fusobacteriales. CONCLUSIONS: This study detected Coriobacteriales in dog faeces, possibly due to the non-selective nature of the %G+C profiling method used in combination with sequencing. Moreover, our work demonstrates that the effect of diet on faecal microbiota can be explained based on the metabolic properties of the detected microbial taxa.  相似文献   
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