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八甲人与空格人属于我国未识别族群。我们去云南省西双版纳调查了八甲人158例(男为61例,女为97例)与空格人71例(男为46例,女为25例)的86项体质指标,初步分析了八甲人与空格人的体质特征。结果如下:1)八甲人的上眼睑皱褶率男为95.08%,女为98.97%;空格人的上眼睑皱褶率男为80.43%,女为100%。八甲人蒙古褶率男为18.03%,女为29.90%;空格人的蒙古褶率男为32.61%,女为64.00%。八甲人与空格人眼裂高度多为中等,眼外角高于眼内角。八甲人男女鼻根高度多为中等。空格人男性鼻根较高,女性鼻根中等。八甲人与空格人男女均为直型鼻梁,鼻基部多为水平方向。八甲人男女颧骨体不突出。八甲人鼻翼高度约为鼻高的1/4。八甲人与空格人男女鼻翼宽与两眼内角间宽几乎等长,多为圆形耳垂,上红唇多为薄唇,唇皮类型多为中等。八甲人眼色多为褐色,空格人眼色多为黑色。2)根据头面部、体部指数分型,八甲人与空格人男女均以高头型率、阔头型率、中鼻型率、中腿型率、宽肩型率、身材矮型率最高。八甲人男女还以圆头型率、长躯干型率、宽胸型率最高。空格人男女还以中胸型率、窄骨盆型率最高。八甲人与空格人男性还以阔面型率最高,而女性则以中面型率最高。3)聚类分析显示八甲人与空格人体质特征属于南方族群类型。 相似文献
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兴安盟3个民族7种不对称行为特征的研究 总被引:31,自引:1,他引:30
于1998年9月对内蒙古兴安盟的汉、蒙古、朝鲜族调查了1852例(男875例,女977例)中学生的7种不对称行为特征(利手、扣手、叠臂、叠腿、起步类型、利足、利眼)。结果显示:(1)3个民族中多数不对称行为特征的右型出现率过半。(2)扣手、叠壁、起步类型的出现率存在一定的民族间差异,而其它4种行征的出现率无此差异。(3)多数特征的出现率男女间差异不显著。(4)不对称行为特征间具有相关的数量较多,程序较高,所有存在相关的特征间均表现为同侧组合特征类型为其亲合特征。 相似文献
3.
在贵州省安顺市对359例屯堡人(男145例,女214例)中学生的7项不对称行为特征(扣手、利手、叠臂、叠腿、利足、起步类型和优势眼)进行了调查。研究结果显示:1)屯堡人除叠臂左型率高于右型率外,其他6项不对称行为特征均为右型率高于左型率;2)屯堡人7项不对称行为特征的出现率均无性别差异;3)与其他族群比较,屯堡人利足右型率和叠臂右型率中等,叠腿右型率和扣手右型率高;4)屯堡人两两不对称行为中,扣手与利手、扣手与叠臂、扣手与叠腿、叠腿与起步相关,利手、利足、起步三种行为彼此相关。 相似文献
4.
小鼠血浆TNF-α、NO、NOS水平与脑不对称的关系 总被引:2,自引:0,他引:2
研究脑不对称对单核巨噬细胞(Mo/MФ)的影响.选用雌性4周龄Balb/c健康小鼠, 用伸爪取食法根据右利分将小鼠区分为左利、右利和双利三组.细菌脂多糖(lipopolysaccharide, LPS)腹腔注射两小时后取血浆检测肿瘤坏死因子-α(TNF-α)、一氧化氮(NO)、一氧化氮合酶(NOS)水平.结果显示: (1)各组间血浆TNF-α和NO、NOS水平的变化: 正常生理组NO水平为双利组高于左利组(P<0.05); LPS刺激后双利组和右利组血浆TNF-α水平高于左利组(P<0.05), NO水平为双利组高于右利组(P<0.01)和左利组(P<0.05), NOS水平在三组小鼠间无明显差别.(2) 血浆TNF-α、NO、NOS与右利分有一定的相关关系, 各项指标随右利分的变化趋势多为双利>右利和左利, 形成一以双利分段(右利分为21~29)为高峰的弓形向上的曲线, 随右利分的增加或减少曲线向两侧延伸和下降.上述结果提示, 脑不对称小鼠单核/巨噬细胞功能存在差异.脑不对称对免疫功能的影响程度与右利分有关, 各免疫指标随右利分的变化趋势多为一以双利分段为高峰的弓形向上的曲线. 相似文献
5.
Two hundred thirty–five (235) normal male participants of the Baltimore Longitudinal Study were classified as right handed, left handed, and ambidextrous on the basis of their grip–strength performance. Their left and right hands were also radiographed and the measurements of the second metacarpal bones were evaluated on the basis of hand dominance. The results indicated that, as a rule, the right hand measurements are higher than those of the left hand, regardless of hand dominance. The bilateral differences in total width, length, total area and cortical area are significant among the right hand dominant and nonsignificant among the left hand dominant. Regardless off hand dominance the bilateral differences in medullary width are nonsignificant. These results suggest an inherent tendency of the right second metacarpal to have more bone than the left regardless of hand dominance. Differential stress due to hand dominance will increase the bilateral difference in the right handed and reduce it in the left handed. 相似文献
6.
Combined gas chromatography-mass spectrometry procedures have been used to establish that the indole acetic acid levels of lateral buds from Phaseolus seedlings rise following removal of the shoot apex.Abbreviations GC
gas chromatograph
- GC-MS
combined gas liquid chromatography mass spectrometry
- bis-TMS
bis-trimethylsilyl
- IAA
indole acetic acid
- MPM
multiple-peak monitoring
- MS
mass spectrometer
- GLC
gas liquid chromatography
- TLC
thin-layer chromatography 相似文献
7.
Functional dominance rather than taxonomic diversity and functional diversity mainly affects community aboveground biomass in the Inner Mongolia grassland
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Qing Zhang Alexander Buyantuev Frank Yonghong Li Lin Jiang Jianming Niu Yong Ding Sarula Kang Wenjing Ma 《Ecology and evolution》2017,7(5):1605-1615
The relationship between biodiversity and productivity has been a hot topic in ecology. However, the relative importance of taxonomic diversity and functional characteristics (including functional dominance and functional diversity) in maintaining community productivity and the underlying mechanisms (including selection and complementarity effects) of the relationship between diversity and community productivity have been widely controversial. In this study, 194 sites were surveyed in five grassland types along a precipitation gradient in the Inner Mongolia grassland of China. The relationships between taxonomic diversity (species richness and the Shannon–Weaver index), functional dominance (the community‐weighted mean of four plant traits), functional diversity (Rao's quadratic entropy), and community aboveground biomass were analyzed. The results showed that (1) taxonomic diversity, functional dominance, functional diversity, and community aboveground biomass all increased from low to high precipitation grassland types; (2) there were significant positive linear relationships between taxonomic diversity, functional dominance, functional diversity, and community aboveground biomass; (3) the effect of functional characteristics on community aboveground biomass is greater than that of taxonomic diversity; and (4) community aboveground biomass depends on the community‐weighted mean plant height, which explained 57.1% of the variation in the community aboveground biomass. Our results suggested that functional dominance rather than taxonomic diversity and functional diversity mainly determines community productivity and that the selection effect plays a dominant role in maintaining the relationship between biodiversity and community productivity in the Inner Mongolia grassland. 相似文献
8.
Diego Raymundo Caroline Elisabeth Randlev Lehmann Norberto Emídio de Oliveira-Neto Vitor Campana Martini Monize Altomare Jamir Prado-Junior Paulo Eugênio Oliveira 《植被学杂志》2023,34(2):e13178
Questions : Woody encroachment in savannas has been associated with changing taxonomic composition and ecosystem function. Interestingly, there is little understanding of how encroachment impacts plant functional diversity and how those changes relate to plant demography, a crucial mediator between taxonomic composition and ecosystem function. Location : Southeastern Brazil. Methods: Using a landscape scale fire suppression experiment in a diverse Brazilian savanna, we quantify how change in species composition over seven years impacted vegetative and reproductive tree functional diversity as determined by new recruits, dead and surviving trees. Results: Over seven years, tree above-ground biomass increased by 15%, while total species richness did not change. Despite minor changes, species composition remained overall similar (82%), with few species contributing significantly to plot dissimilarity over time. There were small changes in vegetative traits, where the community-weighted mean increased in maximum tree height (↑ 2.1%) and specific leaf area (↑ 5.3%), and decreased in wood density (↓ 1.3%) and bark thickness (↓ 9.4%). Changes in reproductive traits were larger than in vegetative traits, with an increase in the prevalence of monoecy (↑ 32.6%), dioecy (↑ 44.2%), large seeds (↑ 20.3%), animal-mediated seed dispersal (↑ 4.9%) and pollination by very small insects (↑ 45.5%), and a decrease in the prevalence of hermaphroditism (↓ 9%), small seeds (6.8%) and pollination by small insects (12.5%). The overall decrease in bark thickness and increase in monoecy and dioecy were mainly driven by characters of the new recruits, while the overall increase in specific leaf area (SLA) and decrease in small seeds appeared largely determined by the loss of trees possessing those traits. Conclusions: Encroachment leads to changes that are likely increasing ecosystem vulnerability to fire and drought. Further, the compositional changes observed appear to drive marked change in reproductive traits, indicating increasing dependence on animals for dispersal and reproduction. Understanding post-hoc encroachment impacts in an era of widespread pervasive encroachment is fundamental to reconciling ecosystem functions such as nutrient cycling and pollination services as there is a loss of species with open ecosystem life-history strategies. Among savannas, there remains an urgent need to understand relationships between woody cover and ecosystem function to determine thresholds in woody cover promoting resilient savanna ecosystems. 相似文献
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A lateral bud growth inhibitor was isolated from etiolated pea seedlings and identified as indole-3-aldehyde. The indole-3-aldehyde content was significantly higher in the diffusates from explants with apical bud and indole-3-acetic acid treated decapitated explants, in which apical dominance is maintained, than in those from decapitated ones releasing apical dominance. When the indole-3-aldehyde was applied to the cut surface of etiolated decapitated plants or directly to the lateral buds, it inhibited outgrowth of the latter. These results suggest that indole-3-aldehyde plays an important role as a lateral bud growth inhibitor in apical dominance of pea seedlings. 相似文献
10.
Carbon storage in tropical forests correlates with taxonomic diversity and functional dominance on a global scale 总被引:2,自引:0,他引:2
Kyle C. Cavanaugh J. Stephen Gosnell Samantha L. Davis Jorge Ahumada Patrick Boundja David B. Clark Badru Mugerwa Patrick A. Jansen Timothy G. O'Brien Francesco Rovero Douglas Sheil Rodolfo Vasquez Sandy Andelman 《Global Ecology and Biogeography》2014,23(5):563-573
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