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排序方式: 共有112条查询结果,搜索用时 23 毫秒
1.
G. Bergström A. -B. Wassgren O. Anderbrant J. Fägerhag H. Edlund E. Hedenström H. -E. Högberg C. Geri M. A. Auger M. Varama B. S. Hansson J. Löfqvist 《Cellular and molecular life sciences : CMLS》1995,51(4):370-380
The main component of the sex pheromone secretion of femaleDiprion pini L. (Hymenoptera: Diprionidae) from insects collected both in Finland and in France has been identified as athreo-3,7-dimethyl-2-tridecanol (8 ng per female) stereoisomer by GC-MS and synthesis. The secretion also contains lower and higher homologues in small amounts (1–4% of the main component). Combined gas chromatographic-electroantennographic detection showed activity in both natural and esterified extracts (acetates and propionates); the esters of the main component gave the largest responses. The acetates and propionates of the eight stereoisomers of 3,7-dimethyl-2-tridecanol were synthesized from enantiomerically highly enriched (>99% ee) building blocks. The stereochemistry of the main component was established to be (2S,3R,7R)-3,7-dimethyl-2-tridecanol by GC analysis of the natural material. It was purified by liquid chromatography prior to the GC analysis of both its pentafluorobenzoates and its isopropylcarbamates on a non-chiral polar column (ECD) and a chiral column (NPD), respectively. Field tests demonstrated that both the acetate and propionate of the main component (100 g of each applied on cotton roll dispensers) were active in attracting males, with or without the presence of several of the minor compounds. Experiments with smaller amounts of the acetate and the propionate (1 g in France and 50 g in Finland) demonstrated that the propionate was more active than the acetate, and that it also caught more males than a blend of the two compounds. 相似文献
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Macgregor S Montgomery GW Liu JZ Zhao ZZ Henders AK Stark M Schmid H Holland EA Duffy DL Zhang M Painter JN Nyholt DR Maskiell JA Jetann J Ferguson M Cust AE Jenkins MA Whiteman DC Olsson H Puig S Bianchi-Scarrà G Hansson J Demenais F Landi MT Dębniak T Mackie R Azizi E Bressac-de Paillerets B Goldstein AM Kanetsky PA Gruis NA Elder DE Newton-Bishop JA Bishop DT Iles MM Helsing P Amos CI Wei Q Wang LE Lee JE Qureshi AA Kefford RF Giles GG Armstrong BK Aitken JF Han J Hopper JL Trent JM Brown KM 《Nature genetics》2011,43(11):1114-1118
We performed a genome-wide association study of melanoma in a discovery cohort of 2,168 Australian individuals with melanoma and 4,387 control individuals. In this discovery phase, we confirm several previously characterized melanoma-associated loci at MC1R, ASIP and MTAP-CDKN2A. We selected variants at nine loci for replication in three independent case-control studies (Europe: 2,804 subjects with melanoma, 7,618 control subjects; United States 1: 1,804 subjects with melanoma, 1,026 control subjects; United States 2: 585 subjects with melanoma, 6,500 control subjects). The combined meta-analysis of all case-control studies identified a new susceptibility locus at 1q21.3 (rs7412746, P = 9.0 × 10(-11), OR in combined replication cohorts of 0.89 (95% CI 0.85-0.95)). We also show evidence suggesting that melanoma associates with 1q42.12 (rs3219090, P = 9.3 × 10(-8)). The associated variants at the 1q21.3 locus span a region with ten genes, and plausible candidate genes for melanoma susceptibility include ARNT and SETDB1. Variants at the 1q21.3 locus do not seem to be associated with human pigmentation or measures of nevus density. 相似文献
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Loos RJ Lindgren CM Li S Wheeler E Zhao JH Prokopenko I Inouye M Freathy RM Attwood AP Beckmann JS Berndt SI;Prostate Lung Colorectal Ovarian 《Nature genetics》2008,40(6):768-775
To identify common variants influencing body mass index (BMI), we analyzed genome-wide association data from 16,876 individuals of European descent. After previously reported variants in FTO, the strongest association signal (rs17782313, P = 2.9 x 10(-6)) mapped 188 kb downstream of MC4R (melanocortin-4 receptor), mutations of which are the leading cause of monogenic severe childhood-onset obesity. We confirmed the BMI association in 60,352 adults (per-allele effect = 0.05 Z-score units; P = 2.8 x 10(-15)) and 5,988 children aged 7-11 (0.13 Z-score units; P = 1.5 x 10(-8)). In case-control analyses (n = 10,583), the odds for severe childhood obesity reached 1.30 (P = 8.0 x 10(-11)). Furthermore, we observed overtransmission of the risk allele to obese offspring in 660 families (P (pedigree disequilibrium test average; PDT-avg) = 2.4 x 10(-4)). The SNP location and patterns of phenotypic associations are consistent with effects mediated through altered MC4R function. Our findings establish that common variants near MC4R influence fat mass, weight and obesity risk at the population level and reinforce the need for large-scale data integration to identify variants influencing continuous biomedical traits. 相似文献
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Revealing modular organization in the yeast transcriptional network 总被引:21,自引:0,他引:21
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Loss and recovery of wings in stick insects 总被引:14,自引:0,他引:14
The evolution of wings was the central adaptation allowing insects to escape predators, exploit scattered resources, and disperse into new niches, resulting in radiations into vast numbers of species. Despite the presumed evolutionary advantages associated with full-sized wings (macroptery), nearly all pterygote (winged) orders have many partially winged (brachypterous) or wingless (apterous) lineages, and some entire orders are secondarily wingless (for example, fleas, lice, grylloblattids and mantophasmatids), with about 5% of extant pterygote species being flightless. Thousands of independent transitions from a winged form to winglessness have occurred during the course of insect evolution; however, an evolutionary reversal from a flightless to a volant form has never been demonstrated clearly for any pterygote lineage. Such a reversal is considered highly unlikely because complex interactions between nerves, muscles, sclerites and wing foils are required to accommodate flight. Here we show that stick insects (order Phasmatodea) diversified as wingless insects and that wings were derived secondarily, perhaps on many occasions. These results suggest that wing developmental pathways are conserved in wingless phasmids, and that 're-evolution' of wings has had an unrecognized role in insect diversification. 相似文献
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Hypotrichosis simplex of the scalp is associated with nonsense mutations in CDSN encoding corneodesmosin 总被引:6,自引:0,他引:6
Levy-Nissenbaum E Betz RC Frydman M Simon M Lahat H Bakhan T Goldman B Bygum A Pierick M Hillmer AM Jonca N Toribio J Kruse R Dewald G Cichon S Kubisch C Guerrin M Serre G Nöthen MM Pras E 《Nature genetics》2003,34(2):151-153
We have identified nonsense mutations in the gene CDSN (encoding corneodesmosin) in three families suffering from hypotrichosis simplex of the scalp (HSS; OMIM 146520). CDSN, a glycoprotein expressed in the epidermis and inner root sheath (IRS) of hair follicles, is a keratinocyte adhesion molecule. Truncated CDSN aggregates were detected in the superficial dermis and at the periphery of hair follicles. Our findings suggest that CDSN is important in normal scalp hair physiology. 相似文献
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Sven Dijkgraaf 《Cellular and molecular life sciences : CMLS》1946,2(11):438-448
Ohne Zusammenfassung 相似文献
9.
Hypophysectomy increases both periosteal resorption and endosteal apposition along the femur diaphysis in rat. Administration of alpha-MSH decreased the periosteal resorption but had no effect on the endosteal apposition. ACTH had only minor effects on the endosteum. Thus, alpha-MSH and ACTH, in the doses used, have different effects on cortical bone in rat. The effect of alpha-MSH on cortical bone could be an effect of the hormone alone or by its stimulation of other factors. 相似文献
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