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261.
Wilfred Y. Fujimoto Richard W. Bergstrom Edward J. Boyko Donna L. Leonetti Laura L. Newell-Morris Patricia W. Wahl 《Obesity (Silver Spring, Md.)》1995,3(Z2):179s-186s
There is good evidence that central (visceral) adiposity is important in the development of the insulin resistance or metabolic syndrome (obesity, hyperinsulinemia, dyslipidemia, glucose intolerance, hypertension, and coronary heart disease). It is proposed that some non-Caucasian populations are especially susceptible to development of this syndrome, and that lifestyle changes may play important etiologic roles. We postulate that this is due to the presence in these populations of a genetic predisposition to weight gain, perhaps related to a “thrifty” genotype, leading to the concentration of weight gain in visceral fat depots, when there is exposure to conditions associated with westernization. 相似文献
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263.
Success in plant genetic transformation depends on the efficiency of explant regeneration and transgene integration. Whereas
the former one depends on explant totipotency, the latter depends on the activity of host DNA repair and chromatin organisation
factors. We analyzed whether factors that result in an increase in recombination frequency can also increase transformation
efficiency. Here, we report that a threefold increase in the concentration of NH4NO3 in the growth medium results in more than a threefold increase in the Agrobacterium tumefaciens-mediated transformation frequency of Nicotiana tabacum plants. Regeneration of calli without selection showed that the increase in transformation frequency was primarily due to
the increase in transgene integration efficiency rather than in tissue regeneration efficiency. PCR analysis of insertion
sites showed a decrease in the frequency of truncations of the T-DNA right border and an increase on the left border. We hypothesize
that exposure to ammonium nitrate modifies the activity of host factors leading to higher frequency of transgene integrations
and possibly to the shift in the mechanism of transgene integrations.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
264.
The methanolysis product of methyl 6-deoxy-3-C-methyl-alpha-L-mannofuranoside has been reassigned as methyl 6-deoxy-3-C-methyl-alpha-L-mannopyranoside by X-ray crystallographic and n.m.r.-spectral analyses. The crystals of methyl alpha-L-evalopyranoside are monoclinic, space group C2, with cell dimensions: a = 12.913(2), b = 8.052(1), c = 9.766(2) A, B = 105.13(2) degrees. The pyranoside ring exists in the 1C4 conformation, with the methoxyl and 3-C-methyl groups axial. Nuclear Overhauser effects were measured for selected proton resonances in the 1H-n.m.r. spectrum. Irradiation of the 3-C-methyl and 5-C-methyl group proton signals resulted in enhancements for H-2, H-4, H-5, and the methoxyl group hydrogen atoms, but not for H-1. 相似文献
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266.
A factor reacting with SRBC and rabbit IgG was obtained under mild conditions from rat thymus and spleen.The isolation procedure includes incubation of thymocytes or splenocytes with IgG-cellulose adsorbent, destruction of cells, washing the adsorbent and elution of an adsorbed material at pH 2. This preparation as well as the purified substance previously obtained by affinity chromatography on IgG-cellulose columns were found to agglutinate both SRBC and autologous erythrocytes. Preincubation in 1% SDS leads to dissociation of the preparation into several components separated by gel electrophoresis.A probable relation of this structure to the rosette forming capacity of T-lymphocytes is discussed. 相似文献
267.
Paranoplocephala aquatica n. sp. is described from Arvicola terrestris and Ondatra zibethica (Rodentia, Cricetidae) in Bulgaria. The new species is characterised by a band-like strobila, a uterus forming a fine reticulate structure in the early stages of development, numerous testes (approximately 92) situated mainly aporally to the ovary in both the median and the aporal lateral fields, few testes positioned anterior to the ovary and genital ducts, the prominent asymmetrical situation of the female organs, the length of the vagina c. 0.65–0.68 of the length of the cirrus-sac, and the external seminal vesicle covered by a cellular sleeve. The new species is distinguished from P. ondatrae, P. macrocephala, P. dasymidis and P. sciuri. The specimens from O. zibethica reported as P. ondatrae by Tenora & Murai (1980) and as Aprostatandrya macrocephala by Spasskii et al. (1951) are believed to belong to P. aquatica. The type-series of P. ondatrae and P. macrocephala are redescribed and figured; metric data and an illustration of the holotype of P. sciuri are presented. The genus Paranoplocephala sensu Tenora et al. (1986) is regarded as a heterogeneous group because of the two patterns of uterine development in the species studied. Taxonomic criteria used for distinguishing the genera Andrya and Paranoplocephala, and some criteria applicable at the species level, are discussed. 相似文献