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161.
Men and women in Great Britain are increasingly involved in a variety of economic and social roles, particularly during their mid-life period. This article examines the changes in role occupancy across four birth cohorts passing throughout mid-life over the period 1985-2000. Data from the General Household Survey is used to investigate the occupancy of four key roles: 'partner', 'parent', 'carer' and 'paid worker', analyzing separate and multiple role occupancies and level of commitment to a particular role. The implications of the findings for health and employment policies is also discussed. 相似文献
162.
Carlton JM Angiuoli SV Suh BB Kooij TW Pertea M Silva JC Ermolaeva MD Allen JE Selengut JD Koo HL Peterson JD Pop M Kosack DS Shumway MF Bidwell SL Shallom SJ van Aken SE Riedmuller SB Feldblyum TV Cho JK Quackenbush J Sedegah M Shoaibi A Cummings LM Florens L Yates JR Raine JD Sinden RE Harris MA Cunningham DA Preiser PR Bergman LW Vaidya AB van Lin LH Janse CJ Waters AP Smith HO White OR Salzberg SL Venter JC Fraser CM Hoffman SL Gardner MJ Carucci DJ 《Nature》2002,419(6906):512-519
Species of malaria parasite that infect rodents have long been used as models for malaria disease research. Here we report the whole-genome shotgun sequence of one species, Plasmodium yoelii yoelii, and comparative studies with the genome of the human malaria parasite Plasmodium falciparum clone 3D7. A synteny map of 2,212 P. y. yoelii contiguous DNA sequences (contigs) aligned to 14 P. falciparum chromosomes reveals marked conservation of gene synteny within the body of each chromosome. Of about 5,300 P. falciparum genes, more than 3,300 P. y. yoelii orthologues of predominantly metabolic function were identified. Over 800 copies of a variant antigen gene located in subtelomeric regions were found. This is the first genome sequence of a model eukaryotic parasite, and it provides insight into the use of such systems in the modelling of Plasmodium biology and disease. 相似文献
163.
Sahin E Colla S Liesa M Moslehi J Müller FL Guo M Cooper M Kotton D Fabian AJ Walkey C Maser RS Tonon G Foerster F Xiong R Wang YA Shukla SA Jaskelioff M Martin ES Heffernan TP Protopopov A Ivanova E Mahoney JE Kost-Alimova M Perry SR Bronson R Liao R Mulligan R Shirihai OS Chin L DePinho RA 《Nature》2011,470(7334):359-365
164.
Direct generation of functional dopaminergic neurons from mouse and human fibroblasts 总被引:2,自引:0,他引:2
165.
Although much attention has been devoted to resveratrol, a unique polyphenol produced by plants and credited as potentially being responsible for the 'French paradox'--the observation that French people have a relatively low incidence of coronary heart disease, even though their diet is high in saturated fats--the oligomers of resveratrol have been largely ignored despite their high biological activity. Challenges in achieving their isolation in sufficient quantity from natural sources, coupled with an inability to prepare them easily synthetically, are seen as the main obstacles. Here we report a programmable, controlled and potentially scalable synthesis of the resveratrol family via a three-stage design. The synthetic approach requires strategy- and reagent-guided chemical functionalizations to differentiate two distinct cores possessing multiple sites with the same or similar reactivity, ultimately leading to five higher-order natural products. This work demonstrates that challenging, positionally selective functionalizations of complex materials are possible where biosynthetic studies have indicated otherwise, it provides materials and tools with which to unlock the full biochemical potential of this family of natural products, and it affords an intellectual framework within which other oligomeric families could potentially be accessed. 相似文献
166.
167.
Vacic V McCarthy S Malhotra D Murray F Chou HH Peoples A Makarov V Yoon S Bhandari A Corominas R Iakoucheva LM Krastoshevsky O Krause V Larach-Walters V Welsh DK Craig D Kelsoe JR Gershon ES Leal SM Dell Aquila M Morris DW Gill M Corvin A Insel PA McClellan J King MC Karayiorgou M Levy DL DeLisi LE Sebat J 《Nature》2011,471(7339):499-503
168.
169.
Maria Luiza Beçak Sylvia Mendes Carneiro K. Fukuda 《Cellular and molecular life sciences : CMLS》1978,34(2):171-173
Summary We describe the production of circles in chromomeric loops during the pachytene stage of the spermatocytes. These circles are found attached to chromatin or already free in the nucleoplasm. Each circle measures an average of 3700 Å in circunference. We suggest that such circles might indicate the presence of tandem repetitions.This work was supported by grants from Brazilian National Research Council-CNPq, Fundaçaó de Amparo à Pesquisa do Estado de S. Paulo-FAPESP and Instituto Butantan Research Found-FEDIB.We are grateful to Dr A. Brunner, Jr, for the permission to use the electron microscope. 相似文献
170.
P. Palatroni Maria Gabriella Gabrielli B. Scattolini 《Cellular and molecular life sciences : CMLS》1981,37(4):409-411
Summary Carbonic anhydrase (CA) activity has been localized histochemically by Hansson's method in Malpighian tubules ofCulex pipiens. The enzyme has been observed on membranes of the cytoplasmic inclusions of Malpighian cells; no CA activity has been found in other cytoplasmic structures. The possible meaning of the localization of the enzyme is discussed. 相似文献