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21.
We examined the interaction of the albino locus with the maternal environment on the behavioral development of two coisogenic strains of mice. Subjects of the pigmented C57BL/6 strain (=B6+/+) and of the albino C57BL/6c2J strain (=B6c/c) were either fostered by a mother of their own strain or cross-fostered at birth to an F1 hybrid dam. They were compared for the amount and daily distribution of activity displayed during 48 h in a seminatural device at weaning and when 75 days old. Food hoarding in the nest and food consumption at the food-search place were also recorded in adult subjects. When animals were fostered by a mother of their own strain, albino mice were more active and less nocturnal than pigmented mice at both ages. They hoarded less food in the nest and ate more at the food-search place. Most of these differences disappeared when both strains were fostered by an F1 dam. The amount of activity displayed during 48 h increased between 21 and 75 days of age. This increase was affected by cross-fostering to an F1 dam in B6c/c mice only. The developmental pattern of daily distribution of activity was changed by F1 dams in B6+/+ mice only. Whereas these influences of F1 dams produced subjects resembling the mother's phenotypic score, maternal effects on hoarding behavior in B6c/c mice produced subjects which did not resemble their foster mother. The results are discussed in terms of different possible ways of hereditary transmission of behavior and some methodological consequences are emphasized.  相似文献   
22.
New HLA-B locus alleles have been found in South American Amerindian populations but were largely absent in North American Amerindian tribes also descended from this first Paleo-Indian migration. We have now extended these studies to the Navajo, descendants of the second Nadene migration. No new functional alleles were found at the B locus of this tribe. This limited study supports the notion that while new B locus variants are common in South American Amerindians, it is more difficult to find new B locus alleles in North American native peoples. Whether this dichotomy is due to differences in pathogen environment and/or population structures between North and South America remains a subject of speculation.  相似文献   
23.
Abstract: Many new HLA-C locus alleles have recently been identified by DNA sequencing, and a molecular based method for their detection using PCR with sequence specific primers has been reported. However, other methods may be more appropriate for the identification of C locus alleles in larger studies. Here we describe one such system, based on PCR sequence specific oligonucleotide probes, (SSOP) for C locus typing. Advantages of SSOP typing compared to SSP are that it is easier to detect new alleles, more cost effective and less time consuming. We have developed a DNA typing method to identify the broad C locus antigens (including those not yet defined serologically) using a minimum of probes with one amplification. We use a C locus specific sense primer in exon 2 and a consensus antisense primer in exon 3, in a two-step PCR, giving a product of 710 bp. Probes were designed with similar melting temperatures (54–56C) that would identify as many alleles as possible. The method was established using DNA from B lymphoid cell lines of known C locus type, mostly 10th workshop homozygous cell lines, plus as many other sequenced cell lines as possible. The system was able to correctly identify their C locus types using only 26 probes. DNA was tested from a panel of serologically typed individuals which included many different heterozygous combinations. We found a high concordance of results, with all discrepancies being additional antigens identified by molecular typing, filling in serological blanks. We can identify all common heterozygote combinations using this method.  相似文献   
24.
Reactivity of murine T cells with viral or bacterial superantigensis clearly correlated with the expression of TCR Vßdomains. Thus, T cells responding to the minor lymphocyte stimulatorylocus (Mls-1a) or staphylococcal enterotoxin B (SEB) expresspredominantly TCR Vß6 or Vß8.2 respectively.We have investigated the involvement of the other major variableelement of the TCR, the V domain, in these superantigen responses.Using a panel of anti-TCR V mAbs, It is demonstrated that theTCR V repertoire among superantigen stimulated Vß6+or Vß8.2+ blasts (responding to Mls-1a or SEB respectivelyin vitro) is altered in comparison with anti-CD3 stimulatedcells expressing the same V domains. Furthermore, the TCR Vrepertoire is strongly skewed in TCR Vß8.2 transgenicmice that have undergone extensive peripheral clonal deletionafter SEB injection. These data imply that the V domain influencessuperantigen recognition by sthe TCR.  相似文献   
25.
目的探讨D7S2 1位点在河北汉族人群分布的多态性 ,为DNA指纹数据库的构建及其法医学应用提供基础资料。方法应用MVR PCR方法和聚丙烯酰胺梯度凝胶电泳银染法对 12 4名河北汉族人群无关个体D7S2 1位点进行了快速检测 ,并进行数字编码。结果每一个体平均得到 3 6个数字编码 ,未发现任何两个无关个体所有编码相同 ,两无关个体 3 6个编码相同的机率为 3 .4 8× 10 -18。三种重复单位a 型、t 型和o 型出现的机率分别为 4 8.5 %、4 9.5 %和 2 .1%。该位点杂合度为 0 .9876,非父排除率为 0 .974 6,多态性信息含量为 0 .9872。结论D7S2 1位点在河北汉族人群中具有高度的多态性 ,聚丙烯酰胺梯度凝胶电泳银染法简便、快速 ,具有一定的实用价值  相似文献   
26.
目的:为了解广西壮族人群D1S80位点群体遗传资料,方法,使用扩增片段长度多态性(Amp-Flp)和PCR结合聚丙烯酰胺凝电脉及银染技术,对300名文本地区壮族无关个体D1S80位点多态性分析,结果,观察到23个等位基因,74个基因型,杂合度,非交排除率,个体识别力及多态信息含量分别为0.824,0.763,0.968,0.875,其基因频率分布符合Hardy-weinberg定律,对5个家系相关个体分析符合孟德尔定律,结认,该方法具有快速,简便,特异性强,灵敏度高特点。  相似文献   
27.
目的;研究DYS19基因座在中国北方汉族、维吾尔族、哈萨克族群体中的遗传多态性及其法医学应用。方法:应用聚合酶链反应后变性聚丙烯酰胺凝胶电泳分离扩增产物结合银染显带的方法,对101例北方汉族、56例维吾尔族、30例哈萨克族无关男性个体的DYS19基因座进行检测。结果:DYS19基因座在3个群体中共检出5种等位基因,基因频率分布范围分别为0.069-0.594,0.071-0.500,0.100-0.667;个人识别机率分别为0.600,0.675,0.491。χ^2检验表明等位基因分布具有明显的人群差异。家系调查符合单体父系遗传方式。结论:DYS19基因座个人识别机率高,属较高鉴别能力的遗传标记系统,且具有明显的人群分布差异,在法医学及人类遗传学研究中具有重要的应用价值。  相似文献   
28.
In chronic experiments on rabbits and rats, parameters of eye homeostasis (intraocular pressure and ocular hydrodynamics) and lungs (water balance and surface-active properties of surfactant) were studied during electrical stimulation of the locus coeruleus against the background of chronic stress induced in rabbits by repeated electrical stimulation of the ventromedial nucleus and in rats by daily immobilization on a platform. Stimulation of the locus coeruleus eliminated ocular hypertension of hypothalamic origin and stress-induced disturbances in surface activity, blood volume, and water balance in the lungs.  相似文献   
29.
The GNAS locus is an imprinted site. The α-subunit of the stimulatory G protein (Gsα) and extralarge variant (XLαs) are the two important products of the GNAS locus. The abnormal expression of Gsα is associated with pseudohypoparathyroidism (PHP) and related disorders, including Albright hereditary osteodystrophy (AHO), pseudopseudohypoparathyroidism (PPHP), and progressive osseous heteroplasia (POH). XLαs protein can mimic the catalytic intracellular synthesis of cyclic adenosine monophosphate (cAMP) by Gsα in response to parathyroid hormone (PTH) stimulation, which may be involved in the pathogenesis of PPHP and POH in patients with paternal GNAS defects. A paternally inherited nonsense variant in the first exon of XLαs in an adult patient may be associated with fractures and osteopetrosis. The relationship between the XLαs product of the GNAS locus and bone remodeling may have been overlooked. Here, we summarize the phenotypes of genetic mouse models and clinical cases of XLαs variations and suggest that the abnormal paternal expression of XLαs may be associated with the development of POH and affect osteoblast and osteoclast differentiation.  相似文献   
30.
Objective. To compare health locus of control scores in women from different ethnic backgrounds.

Method. One‐hundred and twenty‐eight Caucasian, South Asian and Afro‐Caribbean women completed written or orally presented versions of the multidimensional health locus of control scale, as well as ratings of religiousness, health status and occupational status.

Results. South Asian women scored higher on ‘chance’ and ‘powerful others’ locus of control as predicted. They also had higher scores on internality. The ethnic differences persisted after controlling for occupation and health status. High religiousness among the South Asians appeared to explain some, but not all, of their higher scores.

Conclusion. South Asians may differ from British Caucasians in relation to their beliefs about internal and external influences on health.  相似文献   

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