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排序方式: 共有237条查询结果,搜索用时 0 毫秒
181.
182.
Molecular species of the urobilins 总被引:2,自引:0,他引:2
183.
184.
Churchill GA Airey DC Allayee H Angel JM Attie AD Beatty J Beavis WD Belknap JK Bennett B Berrettini W Bleich A Bogue M Broman KW Buck KJ Buckler E Burmeister M Chesler EJ Cheverud JM Clapcote S Cook MN Cox RD Crabbe JC Crusio WE Darvasi A Deschepper CF Doerge RW Farber CR Forejt J Gaile D Garlow SJ Geiger H Gershenfeld H Gordon T Gu J Gu W de Haan G Hayes NL Heller C Himmelbauer H Hitzemann R Hunter K Hsu HC Iraqi FA Ivandic B Jacob HJ Jansen RC Jepsen KJ Johnson DK Johnson TE Kempermann G 《Nature genetics》2004,36(11):1133-1137
The goal of the Complex Trait Consortium is to promote the development of resources that can be used to understand, treat and ultimately prevent pervasive human diseases. Existing and proposed mouse resources that are optimized to study the actions of isolated genetic loci on a fixed background are less effective for studying intact polygenic networks and interactions among genes, environments, pathogens and other factors. The Collaborative Cross will provide a common reference panel specifically designed for the integrative analysis of complex systems and will change the way we approach human health and disease. 相似文献
185.
Jackson IJ 《Nature genetics》2004,36(9):935-936
Several mutant strains of mice have dark skin pigmentation due to an aberrant accumulation of pigment-producing melanocytes in the dermal layer of the skin. A new study shows that three such strains carry activating mutations in the genes encoding the G-protein subunits Galphaq or Galpha11, resulting in more pigment cell precursors and an excess of dermally retained pigment cells at birth. 相似文献
186.
LMNA, encoding lamin A/C, is mutated in partial lipodystrophy 总被引:23,自引:0,他引:23
Shackleton S Lloyd DJ Jackson SN Evans R Niermeijer MF Singh BM Schmidt H Brabant G Kumar S Durrington PN Gregory S O'Rahilly S Trembath RC 《Nature genetics》2000,24(2):153-156
The lipodystrophies are a group of disorders characterized by the absence or reduction of subcutaneous adipose tissue. Partial lipodystrophy (PLD; MIM 151660) is an inherited condition in which a regional (trunk and limbs) loss of fat occurs during the peri-pubertal phase. Additionally, variable degrees of resistance to insulin action, together with a hyperlipidaemic state, may occur and simulate the metabolic features commonly associated with predisposition to atherosclerotic disease. The PLD locus has been mapped to chromosome 1q with no evidence of genetic heterogeneity. We, and others, have refined the location to a 5.3-cM interval between markers D1S305 and D1S1600 (refs 5, 6). Through a positional cloning approach we have identified five different missense mutations in LMNA among ten kindreds and three individuals with PLD. The protein product of LMNA is lamin A/C, which is a component of the nuclear envelope. Heterozygous mutations in LMNA have recently been identified in kindreds with the variant form of muscular dystrophy (MD) known as autosomal dominant Emery-Dreifuss MD (EDMD-AD; ref. 7) and dilated cardiomyopathy and conduction-system disease (CMD1A). As LMNA is ubiquitously expressed, the finding of site-specific amino acid substitutions in PLD, EDMD-AD and CMD1A reveals distinct functional domains of the lamin A/C protein required for the maintenance and integrity of different cell types. 相似文献
187.
J. P. J. Billen B. D. Jackson E. D. Morgan 《Cellular and molecular life sciences : CMLS》1988,44(8):715-719
Summary The Dufour gland of the primitive Australian antNothomyrmecia macrops contains microgram quantities in total of linear alkanes and alkenes from C13 to C30 with heptadecene the major component (66%). In all, 50 substances, including methyl-branched hydrocarbons, aldehydes and acetates, -farnesene and -springene in low nanogram amounts, were identified by gas chromatography-mass spectrometry. 相似文献
188.
Evidence of atmospheric sulphur in the martian regolith from sulphur isotopes in meteorites 总被引:6,自引:0,他引:6
Sulphur is abundant at the martian surface, yet its origin and evolution over time remain poorly constrained. This sulphur is likely to have originated in atmospheric chemical reactions, and so should provide records of the evolution of the martian atmosphere, the cycling of sulphur between the atmosphere and crust, and the mobility of sulphur in the martian regolith. Moreover, the atmospheric deposition of oxidized sulphur species could establish chemical potential gradients in the martian near-surface environment, and so provide a potential energy source for chemolithoautotrophic organisms. Here we present measurements of sulphur isotopes in oxidized and reduced phases from the SNC meteorites--the group of related achondrite meteorites believed to have originated on Mars--together with the results of laboratory photolysis studies of two important martian atmospheric sulphur species (SO2 and H2S). The photolysis experiments can account for the observed sulphur-isotope compositions in the SNC meteorites, and so identify a mechanism for producing large abiogenic 34S fractionations in the surface sulphur reservoirs. We conclude that the sulphur data from the SNC meteorites reflects deposition of oxidized sulphur species produced by atmospheric chemical reactions, followed by incorporation, reaction and mobilization of the sulphur within the regolith. 相似文献
189.
190.
Estevão Alves-Silva Alexandra Bächtold Gudryan Jackson Barônio Helena Maura Torezan-Silingardi Kleber Del-Claro 《Journal of Natural History》2015,49(13-14):841-851
Extrafloral nectary drinking ants are known as effective plant guards, but some herbivores may circumvent ant attacks by foraging on different plant parts or presenting adaptations to avoid ant predation. Here we experimentally investigated the effect of Camponotus blandus on the florivory of the extrafloral nectaried shrub Banisteriopsis malifolia; and a possible spatial segregation between ants and herbivores (leaves and flowers). Flower buds are attacked by Anthonomus weevils. Results revealed no significant influence of C. blandus on the reduction of florivory. Adult Anthonomus are hard-bodied and were immune to ant bites; larvae are endophytic, so protected from ants. Ants and adult beetles were concentrated in different plant parts (leaves and flowers, respectively) so restraining the probability of encounters. Our results indicate that the system C. blandus–Anthonomus–B. malifolia is not stable, as ants receive extrafloral nectar, but are unable to protect the plant against weevils. 相似文献