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1.
Riccardo E. Marioni Lars Penke Gail Davies Jennifer E. Huffman Caroline Hayward Ian J. Deary 《Proceedings. Biological sciences / The Royal Society》2014,281(1781)
Human cognitive ability shows consistent, positive associations with fitness components across the life-course. Underlying genetic variation should therefore be depleted by selection, which is not observed. Genetic variation in general cognitive ability (intelligence) could be maintained by a mutation–selection balance, with rare variants contributing to its genetic architecture. This study examines the association between the total number of rare stop-gain/loss, splice and missense exonic variants and cognitive ability in childhood and old age in the same individuals. Exome array data were obtained in the Lothian Birth Cohorts of 1921 and 1936 (combined N = 1596). General cognitive ability was assessed at age 11 years and in late life (79 and 70 years, respectively) and was modelled against the total number of stop-gain/loss, splice, and missense exonic variants, with minor allele frequency less than or equal to 0.01, using linear regression adjusted for age and sex. In both cohorts and in both the childhood and late-life models, there were no significant associations between rare variant burden in the exome and cognitive ability that survived correction for multiple testing. Contrary to our a priori hypothesis, we observed no evidence for an association between the total number of rare exonic variants and either childhood cognitive ability or late-life cognitive ability. 相似文献
2.
Gail Landsman 《Medical anthropology quarterly》2004,18(1):115-116
They're All My Children: Foster Mothering in America. Danielle F. Wozniak. New York: NYU Press, 2002. + 245 pp. 相似文献
3.
Ken B. Waites Joseph G. Tully David L. Rose Peggy A. Marriott Richard O. Davis Dr. Gail H. Cassell 《Current microbiology》1987,15(6):325-327
Acholeplasmas have been isolated from a variety of animals, insects, and plants, but onlyAcholeplasma laidlawii has previously been found in humans. We have isolatedAcholeplasma oculi in pure culture from the amniotic fluid of a woman at 19 weeks of gestation. The organism was positively identified by growth inhibition, epi-immunofluorescence, and arbutin hydrolysis. Demonstration of organisms directly in amniotic fluid by DNA fluorochrome and immunofluorescence staining provided additional evidence that the isolate was genuine and not a medium contaminant. The remainder of the pregnancy was unremarkable, and a full-term male infant was delivered without complications. Even though there is some evidence possibly associatingA. oculi with various diseases in livestock, the prevalence and significance ofA. oculi in humans has not been determined. 相似文献
4.
Ramon J. Rhine Guy W. Norton Gail M. Wynn Roger D. Wynn 《International journal of primatology》1989,10(4):319-342
Focal-animal feeding data obtained from 64 adult baboons during a 3-year period were used together with equivalent data from
46 infants to evaluate hypotheses predicting selection for a birth peak and to study the baboon’s eclectic/selective feeding
adaptation, with emphasis on differential feeding by sex, developmental trends, and seasonal use of food classes (fruit, leaf,
flower, grass, etc.). The findings suggest that feeding conditions are better in the wet season than in the dry season. Despite
large sexual dimorphism, estimates of total amounts eaten were virtually identical for males and females. Infants used all
of the same plant-food classes as adults, but proportional differences occurred for some food classes in amounts eaten. Foods
eaten proportionately less by infants were probably harder for them to obtain and process or were chosen through inexperience
or for exploration. There was considerable between-year variation in amounts of food classes eaten, but the within-year standard
deviations were similar, as were also the mean amounts eaten per year. An eclectic/selective feeding adaptation has the advantage
of permitting long-run acquisition of adequate nutrition within a context of high feeding variation from season to season
and year to year. Mixed results were obtained from hypotheses about selection for a birth peak. Although a peak occurred in
the early dry season, this was not the optimal time of birth for survival. Survival was highest for individuals born in the
late wet season, when the availability and probably the quality of food for lactating mothers were greatest. 相似文献
5.
Bhuwan Joshi Ayan Chakrabarty Christopher Bruot Hannah Ainsworth Gail Fraizer et al. 《Plant Growth Regulation》1989,8(3):286-286
Book Review
Techniques in molecular biologyJ.M. Walker and W. Gaastra (Eds.), vol. 2. London: Croom Helm, 1987. iv + 332 pages. £14.95. ISBN 0-7099-3673-7 相似文献6.
Ethylcholine mustard aziridinium ion (ECMA) was infused intracerebroventricularly (icv) to rats followed by measurement of two markers of presynaptic cholinergic neurons, choline acetyltransferase (ChAT) activity and high affinity choline transport (HAChT), in the hippocampus and cortex. Bilateral icv administration of 1, 2, or 3 nmol of ECMA per side produced dose-dependent reductions in each marker in the hippocampus, but not in the cortex, one week after treatment. Reductions of 52% and 46% for ChAT activity and HAChT, respectively, were produced in the hippocampus by 3 nmol ECMA. Measurement of these two markers at different times after icv infusion of 2 nmol ECMA/ventricle revealed that the activity of ChAT was reduced to a greater extent than was HAChT in the hippocampus 1 day and 1, 2, 4, and 6 weeks after treatment. The maximal reductions of ChAT activity and HAChT (61% and 53%, respectively) were reached between 1 and 2 weeks after ECMA administration. There was no evidence of regeneration of either marker at 4 or 6 weeks posttreatment. HAChT and ChAT activity in the cortex were not altered at any of the posttreatment times examined.ECMA-induced deficits in hippocampal ChAT activity and HAChT were not counteracted by the following treatments: (i) daily administration of GM1 ganglioside (10 mg/kg, intraperitoneally (ip)) from the day prior to infusion of ECMA until 2 weeks later; (ii) daily administration of GM1 ganglioside between 2 and 6 weeks after infusion of ECMA; and (iii) icv administration of nerve growth factor (NGF) twice per week for 2 weeks after ECMA treatment. Since similar treatments with NGF and GM1 ganglioside ameliorate lesions induced by other methods, these results indicate that the mechanism of lesion formation and the surviving cellular components influence the functional effects of neurotrophic factors. In contrast to the above results, treatment with vitamin E significantly attenuated ECMA-induced deficits of ChAT activity and HAChT. Further studies of the effects of vitamin E on the development of ECMA-induced deficits may help to elucidate the mechanism action of ECMA. 相似文献
7.
8.
Helen L. Henry Chhanda Dutta Noreen Cunningham Raymond Blanchard Robert Penny Chilung Tang Gail Marchetto Shu-Yin Chou 《The Journal of steroid biochemistry and molecular biology》1992,41(3-8)
The synthesis of 1,25(OH)2D3 is a critical control point in the regulation of calcium metabolism, and possibly in the growth and differentiation of a number of cell types. This paper reviews our current understanding of the regulation of this process at the cellular and molecular levels, with the emphasis on the mechanisms of feedback control 1,25(OH)2D3 itself, control of parathyroid hormone, the roles of cyclic AMP dependent protein kinase and protein kinase C, and the interaction between the various intracellular regulators of 1,25(OH)2D3 production. 相似文献
9.
... Despite the need for physicians to be knowledgeable about and open to advances in genetic technology, little is known about the level of preparedness of primary care physicians to offer new genetic tests. Evidence suggests that several barriers exist to physicians adopting genetic tests. These include lack of knowledge, inability to interpret probabilistic information, low tolerance for uncertainty, negative attitudes about their responsibility for genetic counseling and testing, lack of confidence in their clinical skills, and unfamiliarity with ethical issues raised by testing. This paper will explore some of these barriers in further depth, discuss the ethical impact of physician unpreparedness on both patient care and the diffusion of genetic tests, and describe a study that is currently underway to investigate some of these issues. 相似文献
10.
Summary Leaves of birch (Betula pendula Roth) and sycamore (Acer pseudoplatanus L.) were initiated and grown either in a simulated shadelight (80 mol m-2 s-1, R/FR ratio 0.28)/dark photoenvironment or a white light (250 mol m-2 s-1, R/FR>1)/dark photoenvironment. Until the leaves were more than 50% expanded, growth rates (measured every 24 h) were the same for both species in both environments. After this time, growth rate slowed and this correlated well with a decrease in wall extensibility (WEX). Birch leaves in shadelight showed reduced surface acidification and were the first to show reduced growth. WEX under these conditions was particularly low.Daily patterns of leaf growth of the two species were very different. Sycamore leaves showed a slightly higher growth rate in the dark than in shadelight, while birch leaves grew more rapidly in shadelight than in the dark. Limitation of growth of sycamore leaves in light may be explained by a very high yield threshold turgor for growth (Y). The daily pattern of leaf growth shown by birch is more difficult to explain but the importance of a possible limitation of growth by solute availability and a diurnal variation in Y are discussed. 相似文献