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81.
Saccharomyces paradoxus is the closest known relative of the well-known S. cerevisiae and an attractive model organism for population genetic and genomic studies. Here we characterize a set of 28 wild isolates from a 10-km(2) sampling area in southern England. All 28 isolates are homothallic (capable of mating-type switching) and wild type with respect to nutrient requirements. Nine wild isolates and two lab strains of S. paradoxus were surveyed for sequence variation at six loci totaling 7 kb, and all 28 wild isolates were then genotyped at seven polymorphic loci. These data were used to calculate nucleotide diversity and number of segregating sites in S. paradoxus and to investigate geographic differentiation, population structure, and linkage disequilibrium. Synonymous site diversity is approximately 0.3%. Extensive incompatibilities between gene genealogies indicate frequent recombination between unlinked loci, but there is no evidence of recombination within genes. Some localized clonal growth is apparent. The frequency of outcrossing relative to inbreeding is estimated at 1.1% on the basis of heterozygosity. Thus, all three modes of reproduction known in the lab (clonal replication, inbreeding, and outcrossing) have been important in molding genetic variation in this species. 相似文献
82.
Genomewide scan in families with schizophrenia from the founder population of Afrikaners reveals evidence for linkage and uniparental disomy on chromosome 1 下载免费PDF全文
Abecasis GR Burt RA Hall D Bochum S Doheny KF Lundy SL Torrington M Roos JL Gogos JA Karayiorgou M 《American journal of human genetics》2004,74(3):403-417
We report on our initial genetic linkage studies of schizophrenia in the genetically isolated population of the Afrikaners from South Africa. A 10-cM genomewide scan was performed on 143 small families, 34 of which were informative for linkage. Using both nonparametric and parametric linkage analyses, we obtained evidence for a small number of disease loci on chromosomes 1, 9, and 13. These results suggest that few genes of substantial effect exist for schizophrenia in the Afrikaner population, consistent with our previous genealogical tracing studies. The locus on chromosome 1 reached genomewide significance levels (nonparametric LOD score of 3.30 at marker D1S1612, corresponding to an empirical P value of.012) and represents a novel susceptibility locus for schizophrenia. In addition to providing evidence for linkage for chromosome 1, we also identified a proband with a uniparental disomy (UPD) of the entire chromosome 1. This is the first time a UPD has been described in a patient with schizophrenia, lending further support to involvement of chromosome 1 in schizophrenia susceptibility in the Afrikaners. 相似文献
83.
D. R. R. Burt 《Development genes and evolution》1925,104(3-4):421-433
Summary The head and foot ofPelmatohydra oligactis function in regeneration as unipotent systems. The exact extent of the unipotent tissue immediately posterior to the tentacles and anterior to the foot is not determined in these experiments. The intermediate tissue is pluripotent.The potentiality for head formation is stronger at the oral end and decreases towards the aboral end as the potentiality for foot formation increases.In these grafting experiments the stock has no influence over the graft which retains its individuality.Preliminary account im Akademischen Anzeiger, Wien, No. 24. 22. November 1923: Mitteilungen aus der Biologischen Versuchsanstalt der Akademie der Wissenschaften in Wien, Zoologische Abteilung, Vorstand:H. Przibram. Nr. 113. Kopf und Fuß des Süßwasserpolypen,Pelmatohydra oligactis Pall., als unipotente Systeme vonD. R. R. Burt. 相似文献
84.
85.
An attempt is made to provide a tool for systematically analyzing variations of outdoor human energy budgets and skin temperatures as a result of different urban street canyon geometries and vegetative properties. To this end, three previously developed numerical models were combined. The interaction of the models and the derivation of the necessary human-urban view-factors is discussed. Some sample results are given for non-urban macadam and park plains, to be used later as standards in the comparison of the impact of urban morphology on human comfort. 相似文献
86.
87.
Summary The method of estimating interactions proposed independently by Pimm and Schoener is studied using field data from the community of rodents which lives in the arid, rocky habitats of Israel. One important problem the method addresses is how to remove the effects of habitat heterogeneity on the estimate. We tried six different variations of the analysis scheme outlined by Crowell and Pimm, and found their results qualitatively inconsistent. This was especially true when we compared the results produced from separate habitat variables with those produced from the principal components of the habitat variation.Another problem, this one not previously addressed, is great variation in the average abundance of the different species. We discovered that the ratio of the average abundances of two species is the best predictor of the value of their coefficients of interaction. Common species appear to have weak influence on rare ones; rare ones appear to have strong influence on common ones. The statistical mechanism which produces this relationship is clear, indicating that the relationship is an artifact. 相似文献
88.
Chris Musello Richard Chalfen Ben Burt Timothy Asch Riv‐Ellen Prell Linda L. Layne 《Visual Anthropology: Published in cooperation with the Commission on Visual Anthropology》2013,26(4):475-516
The Family Album. A film by Alan Berliner. 16mm, 55min, b/w. Distributed by Filmmakers Library, Inc. Beyond Words—Images from America's Concentration Camps. By Deborah Gesensway and Mindy Roseman. 1987, 176 pages, illustrated. Ithaca: Cornell University Press. Price: cloth $24.95. The Lau (Granada Television “Disappearing World” Series). A film by Leslie Woodhead, producer‐director; Jon Woods, camera; Ray French, sound; Kimball Horton, editor; David Wasson, researcher; and Pierre Maranda, anthropological consultant. 1987, video, color, 52 minutes. Dialogues: Lau. Subtitles: English. Narration: English. Distributed by Granada TV International, Suite 3468, 1221 Avenue of the Americas, New York, NY 10020, tele. 212–242–2363. Price: on application. Men's Lives: The Surfmen and Baymen of the South Fork. By Peter Matthiessen. 1986, New York: Random House. Price: hardcover $29.95; softcover $7.95 (Vintage Press); limited edition $200 (University of Washington Press, Seattle). In Her Own Time. A film by Lynne Littman with Barbara Myerhoff. 1986, 16mm, color, 60 minutes. Distributed by Direct Cinema, Ltd., P.O. Box 69589, Los Angeles, CA 90060, tele. 213–652–8000. Price: 16mm—purchase $895, rental $100; video—purchase $350, rental $50 (prices quoted are for educational institutions only). The Miracle of Intervale Avenue. A film by Irving Rappaport, producer; Ken Howard, director; and Jack Kugelmaas, associate producer. 1983, 16mm, color, 65 minutes. Catalog #430. Distributed by Ergo Media, Inc., P.O. Box 2037, Teaneck, NJ 07666, tele. 201–692–0404. Some Babies Die. A film by Martyn Landon Down. Australia, 16mm, color, 54 minutes. Distributed by The University of California Extension Media Center, 2176 Shattuck Avenue, Berkeley, CA 94704, tele. 415–642–1340. Price: 16mm—purchase $850, rental $60; video—purchase $450, rental $60. El Sebou’: The Egyptian Birth Ritual. A film by Fadwa El Guindi; produced by El Nil Research Project; co‐sponsored by the Office of Folklife, Smithsonian Institution. 1986, 16mm, color, 27 minutes. Distributed by El Nil Research Project, 1157 Beverwil Drive, Los Angeles, CA 90035, tele. 213–553–5645. Price: 16mm—purchase $570, rental $70; video—purchase $370. Screenings: Society for Visual Anthropology (1987 Award for Excellence); 1987 Margaret Mead Film Festival; Royal Anthropological Institute (1988 Commendation). The Making of El Sebou‘ Classified People. Yolande Zauberman, director; produced by OBSESSION/INA/CNC/ FR3‐TOULOUSE; Dewald Aukema, camera; Tony Bensusan, sound; Jean‐François Naudon, editor. 1987, 16mm, color, 53 minutes. Distributed by TELEMONDIS, 15, rue Mesnil, 75016, Paris, tele. 47–27–03–84, telex: 649 078 TELMOND. In U.S., distributed by Filmmaker's Library, 124 E. 40th Street, New York, NY 10016, tele. 212–355–6545. Price: 16mm—rental only $150; video (½″ or ¾″)—purchase $75, rental $75. Screenings: Festival of Women's Films at Créteil (Prix de Jury); Festival of Young Directors at Belfort (Prix de Publique); Bilan du Film Ethnographique 1988 (Prix Nanook/Grand Prix); 1988 Cinéma du Réel; 1987 Margaret Mead Film Festival; U.S. Public Television. To Cross the Border: An interview with Filmmaker Yolande Zauberman, Paris, May 1988. 相似文献
89.
The presence of muscarinic receptors in sheep and rat pineals was detected by binding of [3H]quinuclidinyl benzilate ([3H]QNB), a potent and specific muscarinic antagonist. [3H]QNB binding to sheep pineal membrane resuspensions was saturable and reversible, with a rate constant for association at 37°C of 6×108M?1min?1 and a rate constant for dissociation of 1×10?2min?1. Kinetic and saturation experiments yielded an equilibrium dissociation constant of 13–18 pM and a concentration of binding sites equivalent to 1.1 pmol/g of original wet weight. This is only about 5% of the level of β-adrenergic receptors. Competition by a variety of cholinergic drugs confirmed the muscarinic nature of the binding sites. Experiments in rats failed to detect a significant decrease in pineal [3H]QNB binding following bilateral superior cervical ganglionectomy, suggesting that the binding sites are not localized exclusively on sympathetic terminals. 相似文献
90.