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本文研究了宁夏汉族男性不育患者指长波动性不对称(FA)与不育的相关性。分析了宁夏汉族男性不育患者308例(原发组196例, 继发组112例)各指指长FA(2FA、3FA、4FA、5FA)及复合FA(CFA)的均值及其均值的差异性; 比较了指长FA与a+b级精子比率间的关系。结果表明: 1)原发组各指指长FA均值均高于继发组, 且2FA(P<0.01)、4FA(P<0.05)和CFA(P<0.05)有显著性差异; 2)原发组a+b级精子比率显著低于继发组(P<0.05); 3)原发组2FA分布在|L-R|≥0.04组显著增高(P<0.05), 2FA与a+b级精子比率呈高度负相关(P<0.001)。 相似文献
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饲养方式、社会环境和化学污染是影响动物发育不稳定的重要环境胁迫因素,会使动物种群的适应和竞争能力等指数降低。而波动性不对称FA(Fluctuating asymmetry)的水平可用来指示某一种群对这种环境压力的进化和适应能力。FA的测量方法比常规的参数更加灵敏,而且可将环境压力的影响定量化,同时其测定和分析都比较简单,不需要昂贵的设备和试剂,使研究和监测成本大大降低。 相似文献
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波动性不对称 (Fluctuating asymm etry,FA)是指相对于生物两侧对称发育的一种细微的随机偏离 ,通常用来指示生物在外界环境压力下发育的稳定性程度。 2 0 0 2年在我国北方棉区 1 3个具有 1~ 5 a转 Bt基因棉种植史的市、县采集了棉铃虫上灯蛾 ,测定了各点成虫后足腿节的波动性不对称 (Fluctuating asymmetry,FA)。结果表明 ,1 2个采集地的棉铃虫后足腿节均表现出 FA;相关性分析发现 ,各采集点的 FA值与 Bt棉的种植年代间存在着显著的负相关关系 (r=- 0 .77) ,显示出棉铃虫自然种群对 Bt棉的适应性随着 Bt棉种植时间延长而渐增的趋势。讨论了棉铃虫对 Bt棉的适应以及 FA作为棉铃虫田间种群对 Bt棉早期抗性监测指标的可能性 相似文献
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空间诱变条件下蜜蜂后代的波动性不对称 总被引:1,自引:0,他引:1
利用航天搭载的雄蜂精液对处女王进行人工授精,产卵后大量培育后代蜂王;以SP1、SP2及SP3代蜂王后代工蜂为研究对象,考查波动性不对称(fluctuating asymmetry,FA)在不同代次种群中各对称性状间的表现情况。结果表明:SP1、SP2和SP3代工蜂的前翅长及肘脉a均表现出FA,SP1、SP2代的对照组中均未出现,而SP3代的对照组蜂群则全部表现出FA;与对照蜂群相比,空间诱变后代的前翅长及翅脉a的FA值均较高。此外,讨论FA在蜜蜂种群对生态环境适应性上应用以及利用蜜蜂的FA来监测环境污染的可能性及发展前景。 相似文献
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植物发育的波动性不对称(fluctuating asymmetry,FA)与环境之间具有密切的关系。该研究以城市常用绿化树种大叶女贞(Ligustrum lucidum Ait.)和小叶女贞(Ligustrum quihoui Carr.)为对象,在西安市区9个空气质量监测点采集了两树种成熟叶片样品,以叶脉为对称轴测定叶左右两边的半宽度、半周长和半面积,计算其相应FA,考察植物叶片FA对空气环境条件变化的响应特征,探讨叶FA作为空气质量指标的可行性。结果表明:大叶女贞叶周长(FAP)、宽度(FAW)和面积(FAA)波动性不对称分别为0.051、0.063和0.082,小叶女贞分别为0.043、0.082和0.102,均以FAA最大,FAP最小;FAP、FAW和FAA在树种间、立地环境间均具有极显著的差异;两树种的FAP与空气中SO_2浓度之间存在显著相关性。可见,大叶女贞和小叶女贞叶的波动性不对称特征对不同环境条件具有敏感的反应,具有作为生物监测指标的潜力,但在合适监测物种和叶特征指标的选择、样本数确定以及FA与空气特征污染物的关系等方面有待深入探讨。 相似文献
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本文报告了210例糖尿病患者皮纹的11个参数,与对照组相比,各型男患者的足底(足母)趾球区纹型中,三角斗形纹均显著增多;NIDDM型男女患者atd角显著变小;NIDDM型女患者通贯手出现率显著增高;NIDDM型女患者主线C走向I_3的百分率显著增高;各型女患者的指纹中斗形纹出现率显著增高,而尺箕著减少。 相似文献
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在转Bt基因棉压力下棉铃虫和异色瓢虫的波动性不对称 总被引:7,自引:0,他引:7
以取食转Bt基因棉的棉铃虫和取食转Bt基因棉上的蚜虫的异色瓢虫为研究对象,结合各自的适合度参数考察了波动性不对称(fluctuating asymmetry, FA)在不同种群中各对称性状间的表现情况。结果表明: 处理组棉铃虫种群的前、中、后足腿节,前翅肘横脉,前翅副室短径,后翅翅长均表现出FA;与对照种群比较,前足腿节与后翅翅长的FA值较高。 适合度参数测定结果显示,棉铃虫卵孵化率与成虫寿命显著低于对照种群,而成虫产卵量和幼虫发育历期与对照种群差异不显著。异色瓢虫取食了转Bt基因棉上的蚜虫后对其适合度各参数及各虫龄的捕食功能反应均无不良影响,其后翅翅长表现出FA,但与对照种群的FA值无显著差异。FA的大小与种群适合度间存在一定的联系,尚需做进一步的分析。 相似文献
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为探讨体育专业大学生指长比及其波动性不对称的特征,进而为体质人类学和优秀运动员身体形态特征的研究积累基础资料,本研究特招募374名18~25岁发育正常的汉族在校大学生为研究对象,按照专业和性别分为男生体育组(n=60)、男生普系组(n=143)、女生体育组(n=61)和女生普系组(n=110),计算各个指长比及两侧指长比的波动不对称值并进行检验。结果显示男生体育组与男生普系组之间的指长比(R)存在统计学差异(P<0.05),差异主要表现在R2/5、R3/5和R4/5上,而女生体育组与女生普系组之间的指长比不存在统计学差异(P>0.05)。结果还显示男生体育组与男生普系组之间的偏差(σ)存在统计学差异(P<0.05),差异主要表现在σ2/3和σ2/3上。而女生的指长比偏差在体育组与普系组之间不存在统计学差异(P>0.05)。通过分析讨论提示出大学生指长比及指长比偏差与性别和运动能力有关,R3/5及σ3/5可能与早期生长发育过程中的性激素的暴露水平有关,而且有望成为运动员选材的新生物标记。 相似文献
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LU Hong; HUO Zheng-hao; DANG Jie; SHI ZHi-Yun; PENG Liang; JIAO Hai-yan; ZHONG Hui-jun 《人类学学报》2010,29(04):431
The characteristics of dermatoglyphic parameters found in both hands of 256 men from the Ningxia Han nationality (control group and coronary heart disease sample of 128 each) were studied. The fluctuating asymmetry (FA) was also analyzed with the following results: 1) the mean value of FRC, TFRC and a-b RC were lower in the coronary heart disease patients compared to the control group; 2) the sample of coronary heart disease patients showed a significant difference in atd [ Feng: need to clarify “ adt ”] ( P < 0 . 0 5 ) found in both hands; 3 ) there was a significant difference in the FAII (P < 0. 01) and FAV (P < 0. 05) between the two groups with the coronary heart disease patient sample with a higher FA. There was also a significant difference in |R-L|≥7 on distribution of atd angle between two samples. [Feng: please clarify the abbreciations used in this abstract-here“| R - L | > - 7”] 相似文献
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本文采用随机整体抽样的方法分析了先天性心脏病患者129例(男性59例, 女性70例) 和正常对照人群133例(男性69例, 女性64例) 13项皮纹波动不对称性(Fluctuating asymmetry, FA)的分布特征。结果表明: (1)先天性心脏病患者组与正常对照组在13项皮纹波动不对称性指标中均未出现显著性别差异; (2)先天性心脏病患者组与正常对照组在FAⅥ(P<0.05)和FAⅦ(P<0.01)两项有显著性差异, 表现为患者组明显增高, 提示先天性心脏病患者在胚胎发育早期易受到环境因素影响, 具有较高的发育不稳定性。 相似文献
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DANG Jie; LI Xia; HUO Zheng-hao; ZHONG Hui-jun; ZHU Yong-sheng; PENG Liang; JIAO Hai-yan; LU Hong 《人类学学报》2010,29(03):276
The purpose of this paper is to analyze the fluctuating asymmetry (FA) of the dermatoglyphic count in individuals with congenital heart disease (CHD) from Ningxia, China. Fluctuating asymmetry refers to small random deviations from perfect symmetry in bilaterally paired structure, and is the result of interactions between developmental disturbance and developmental stability. Fluctuating asymmetry has a low heritability, and can be a measure of individual quality but also an indicator of developmental stability. Computing FA was done using the absolute differences between bilateral measurements ( calculated as FA = | R - L | ) , and in order to avoid count and measure error, we choose the equation, FA ij = 100 ×| (XiR - XiL ) /0. 5 ×(XiR - XiL)-1/n×[(XiR - XiL)/0.5×(XiR - XiL)].A random sample of 129 CHDs(59 males and 70 females) was compared to 133 healthy controls (69 male and 64 female), with a study of 13 FA counts between them. The results were as follows: 1. There was no significant difference between two sexes in both CHDs and controls in all 13 FA counts; 2. There was a significant difference in FA VI and FA VII between two groups, and that CHD patients had significantly higher FA rates. These results may indicate that during the course of fetal development, the CHD fetus is much more senstive to a variety of external environmental factors and thus,has higher developmental instability. 相似文献
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Fluctuating asymmetry was measured by the Pearson correlation coefficient between a-b ridge-counts of the right and left hands. Such data were available for 38 samples, which were grouped by major geographical regions. Significant heterogeneity exists within some of the geographical groups but the between geographical group component is highly significant in both sexes. Our results show that a sizable fraction of variation in fluctuating asymmetry is related to geographical race. There is no evidence that it follows environmental or ecological lines. The variation between geographical races suggests that there is a genetic component in the magnitude of fluctuating asymmetry. 相似文献
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Bilateral symmetry is widespread in animal kingdom, however most animal can deviate from expected symmetry and manifest some kind of asymmetries. Fluctuating asymmetry is considered as a tool for valuating developmental instability, whereas directional asymmetry is inherited and could be used for evaluating evolutionary development. We use the method of geometric morphometrics to analyze left/right asymmetries in the whole body, in two sites and totally six populations of Ceroglossus chilensis with the aim to infer and explain morphological disparities between populations and sexes in this species. In all individuals analyzed we found both fluctuating asymmetry and directional asymmetry for size and shape variation components, and a high sexual dimorphism. Moreover a high morphological variability between the two sites emerged as well. Differences in diet could influence the expression of morphological variation and simultaneously affect body sides, and therefore contribute to the symmetric component of variation. Moreover differences emerged between two sites could be a consequence of isolation and fragmentation, rather than a response to local environmental differences between sampling sites. 相似文献
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R L Costa 《American journal of physical anthropology》1986,70(1):119-123
The condyles of 72 aged and sexed Haida Indians were measured for anteroposterior and mediolateral diameter and their approximate areas calculated. Dental wear was assessed for the same individuals. Asymmetry of condyle size did not appear to change with age. In a pair-wise analysis, no relationship was found between the largest of a pair of condyles and the most worn side of the dentition. The difference in size between each pair of condyles (normalized for individual size) was plotted as a histogram and found to have a normal distribution with a mean of 0 and no skewness. Condyle asymmetry does not appear to be related to differential chewing forces but more closely fits the model of fluctuating asymmetry. 相似文献
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Fluctuating asymmetry (FA) is frequently used as a potential marker of developmental stress. It is usually assumed that the distribution of FA within a population is statistically normal with a mean of zero. The relationships between three different FA-dependent survival functions and the resultant FA distribution of surviving individuals are explored. It is shown that with any biologically plausible relationship between survival and FA the resultant distribution is not normal and that this non-normality is dependent upon the form of the survival-FA relationship. Two survival probability functions resulted in leptokurtic distributions, whereas a third generated a slight decline in kurtosis values. 相似文献
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LOREN H. SMITH 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1998,31(2):99-110
Asymmetry in fossils can arise through a variety of biological and geological mechanisms. If geological sources of asymmetry can be minimized or factored out, it might be possible to assess biological sources of asymmetry. Fluctuating asymmetry (FA), a general measure of developmental precision, is documented for nine species of lower Paleozoic trilobites. Taphonomic analyses suggest that the populations studied for each taxon span relatively short time intervals that are approximately equal in duration. Tectonic deformation may have affected the specimens studied, since deviations from normal distributions are common. Several measures of FA were applied to 3–5 homologous measures in each taxon. Measurement error was assessed by the analysis of variance (ANOVA) for repeated measurements of individual specimens and by analysis of the statistical moments of the distributions of asymmetry measures. Measurement error was significantly smaller than the difference between measures taken on each side of a specimen. However, the distribution of differences between sides often deviated from a mean of zero, or was skewed or kurtosic. Regression of levels of FA against geologic age revealed no statistically significant changes in levels of asymmetry through time. Geological and taphonomic effects make it difficult to identify asymmetry due to biological factors. Although fluctuating asymmetry is a function of both intrinsic and extrinsic factors, the results suggest that early Cambrian trilobites possessed genetic or developmental mechanisms used to maintain developmental stability comparable to those of younger trilobites. Although the measures are biased by time averaging and deviations from the normal distribution, these data do not lend strong support to 'genomic' hypotheses that have been suggested to control the tempo of the Cambrian radiation. 相似文献

