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本实验采用国外新近提出的一项能综合评价机体气体交换系统中各氧降阶差时运氧能力的适应水平高低的重要指标──氧比传导(MO2-SC),研究了高原鼠兔气体交换系统运氧能力的低氧适应特征及规律。结果表明,对照条件下,在吸入气(I)至肺泡气(A)(I→A)、A至动脉血(a)(A→a)、a至混合静脉血(v)(a→v)及I→v各阶差中,以A→a的MO2-SC运氧能力最大。低氧15mm后,I→A及a→v的MO2-SC均显著升高,并以I→A增加最为显著,该水平运氧能力是对照的2倍,增长120.9%;而A→a及I→vMO2-SC变化无显著性差异。低氧30min时,I→A的MO2-SC继续显著增长,运氧能力是对照的2.7倍,增长170.7%,其余3个氧降阶差的MO2-SC无显著性改变。以上结果表明,高原鼠兔低氧代偿贮备较大,尤以肺泡气至动脉血阶差最为重要,而通气氧传导能力的增强也是高原鼠兔低氧适应的主要原因。 相似文献
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Tang Xianfa Cheng Hui Cheng Lu Liang Bo Chen Mengyun Zheng Xiaodong Xiao Fengli 《Molecular biology reports》2021,48(8):5955-5964
Molecular Biology Reports - Vitiligo is a complex disease in which patchy depigmentation is the result of an autoimmune-induced loss of melanocytes in affected regions. On the basis of a... 相似文献
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Xie X Molina J Hernandez R Reynolds A Boyko AR Bustamante CD Purugganan MD 《PloS one》2011,6(6):e20670
Oryza sativa or Asian cultivated rice is one of the major cereal grass species domesticated for human food use during the Neolithic. Domestication of this species from the wild grass Oryza rufipogon was accompanied by changes in several traits, including seed shattering, percent seed set, tillering, grain weight, and flowering time. Quantitative trait locus (QTL) mapping has identified three genomic regions in chromosome 3 that appear to be associated with these traits. We would like to study whether these regions show signatures of selection and whether the same genetic basis underlies the domestication of different rice varieties. Fragments of 88 genes spanning these three genomic regions were sequenced from multiple accessions of two major varietal groups in O. sativa--indica and tropical japonica--as well as the ancestral wild rice species O. rufipogon. In tropical japonica, the levels of nucleotide variation in these three QTL regions are significantly lower compared to genome-wide levels, and coalescent simulations based on a complex demographic model of rice domestication indicate that these patterns are consistent with selection. In contrast, there is no significant reduction in nucleotide diversity in the homologous regions in indica rice. These results suggest that there are differences in the genetic and selective basis for domestication between these two Asian rice varietal groups. 相似文献
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Phase coding in a neural network composed of neural oscillators with inhibitory neurons was studied based on the theory of
stochastic phase dynamics. We found that with increasing the coupling coefficients of inhibitory neural oscillators, the firing
density in excitatory population transits to a critical state. In this case, when we increase the inhibitory coupling, the
firing density will come into dynamic balance again and tend to a fixed value gradually. According to the phenomenon, in the
paper we found parameter regions to exhibit those different population states, called dividing zones including flat fading
zone, rapid fading zone and critical zone. Based on the dividing zones we can choose the number ratio between inhibitory neurons
and excitatory neurons in the neural network, and estimate the coupling action of inhibitory population and excitatory population.
Our research also shows that the balance value, enabling the firing density to reach the dynamic balance, does not depend
on initial conditions. In addition, the critical value in critical state is only related to the number ratio between inhibitory
neurons and excitatory neurons, but is independent of inhibitory coupling and excitatory coupling. 相似文献
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Li Meng Li Wang Huayang Tang Xianfa Tang Xiaoyun Jiang Jinhua Zhao Jing Gao Bing Li Xuhui Fu Yan Chen Weiyi Yao Wenying Zhan Bo Wu Dawei Duan Changbing Shen Hui Cheng Xianbo Zuo Sen Yang Liangdan Sun Xuejun Zhang 《PloS one》2014,9(5)
Background
We confirmed that the filaggrin gene mutation c.3321delA is associated with atopic dermatitis in our previous genome wide association study of the Chinese Han population. c.3321delA is the most common filaggrin gene mutation in Chinese atopic dermatitis patients but is not present in European populations.Objective
To investigate the genetic model for the c.3321delA mutation and to determine the correlation between c.3321delA and atopic dermatitis clinical phenotypes in the Chinese Han population.Method
The filaggrin gene mutation c.3321delA was sequenced in 1,080 atopic dermatitis patients and 908 controls from the Chinese population. The χ2 test, ANOVA,nonparametric tests and logistic regression were used to investigate the relationship between the c.3321delA genotype and atopic dermatitis clinical phenotypes in the Chinese Han population.Results
Analyses of the genetic model revealed that the additive model best described the c.3321delA mutation (P = 3.09E-11, OR = 3.43, 95%CI = 2.38–4.96). Stratified analyses showed that the c.3321delA allele frequency distribution is significantly associated with concomitant skin xerosis (P = 1.68E-03, OR = 2.13,95%CI = 1.32–3.46), palmar hyperlinearity (P = 3.64E-17, OR = 4.0,95%CI = 2.86–5.70), white dermatographism (P = 4.25E-03, OR = 1.82,95%CI = 1.22–2.71), food intolerance (P = 1.51E-03, OR = 1.76,95%CI = 1.23–2.50) and disease severity ( P = 9.67E-05).Conclusion
Our study indicates that the filaggrin gene mutation c.3321delA is associated with clinical phenotypes of atopic dermatitis in the Chinese Han population, which might help us gain a better understanding on the pathogenesis of atopic dermatitis. 相似文献9.
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中枢神经系统急性低氧反应的个体差异及其评定 总被引:1,自引:0,他引:1
为了观察急性低氧条件下中枢神经系统机能状态的改变,用改进了的方法测定了健康人乘车抵达海拔4700m高原现场前后,和在实验室内吸入低氧混合气体(相当于海拔4500~4700m)前后的“光单纯反应时”。在两种条件下,所得结果基本相同:人体中枢神经系统对急性低氧的反应有明显个体差异,可区别出稳定型、兴奋型和抑制型三类。其中抑制型现场和实验室分别有83%及75%的人出现急性低氧反应,其他两型合并统计,分别有79%及80%的人基本无反应。反应时抑制型的人急性低氧反应的发生率高。反应时测定方法用来评定急性低氧反应出现程度,其结果与症状学评定法相比,在两种条件下,吻合率分别为81%及78%,不吻合率分别为19%及22%,其中假阳性率分别为6%及10%,假阴性率分别为14%及12%。 相似文献