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1.
In the present paper the frequencies of individuals without middle phalangeal hair was found as 55.75% in the Tibetan males and 68.61% in females. Sex differences were noticed in the present sample. Populations of Mongoloid affinity seems to have a marked increase in the frequency of individuals without phalangeal hair and the present Tibetan sample reflects this tendency.  相似文献   

2.
Data on middle phalangeal hair (MPH) among unrelated autochtonous individuals from Delta de l'Ebre and Murcia (Spain) show remarkable sexual differences in the Murcia population. The Delta de l'Ebre sample seems to have more pilosity than the Murcia sample. In the Spanish and Mediterranean variation range, Delta de l'Ebre is located between the populations with high pilosity while Murcia females show an extremely low value for this trait.  相似文献   

3.
Data relating to middle phalangeal hair (MPH) among unrelated individuals of both sexes born and living in Sardinia are presented. The occurrence of MPH is generally manifested on the 3-4-5 digits of both hands in the two sexes. The observed sex differences are statistically non-significant. The Sardinian sample seems to have a marked decrease in the frequency of individuals with MPH with regard to Mediterranean and other European populations.  相似文献   

4.
宁夏回族、汉族人手指指毛的分布   总被引:5,自引:1,他引:4       下载免费PDF全文
调查了宁夏回族316例(男性166例,女性150例)、汉族542例(男性253例,女性289例)手指指毛的分布。结果表明,手指近侧指节除回族中有2例女性没有指毛外,其余均生指毛;中间指节指毛出现率在同一民族男女间、回汉族间均无显著性差异(P>0.05);各指中间指节指毛出现频率的排列顺序为4>3>5>2;每指两侧指毛分布不对称;左、右手同位指指毛分布基本对称。比较分析了11个民族共13个群体有中间指节指毛的基因频率。  相似文献   

5.
Tricho–rhino–phalangeal syndrome (TRPS) is a rare autosomal dominant disorder. Deletion or mutation of the TRPS1 gene leads to the tricho–rhino–phalangeal syndromes type I or type III. In this article, we describe a Chinese patient affected with type I TRPS and showing prominent pilar, rhinal and phalangeal abnormalities. Mutational screening and sequence analysis of TRPS1 gene revealed a previously unidentified four-base-pair deletion of nucleotides 1783–1786 (c.1783_1786delACTT). The mutation causes a frame shift after codon 593, introducing a premature stop codon after 637 residues in the gene sequence. This deletion is an unquestionable loss-of-function mutation, deleting all the functionally important parts of the protein. Our novel discovery indicates that sparse hair and metacarpal defects of tricho–rhino–phalangeal syndromes in this patient are due to this TRPS1 mutation. And this data further supports the critical role of TRPS1 gene in hair and partial skeleton morphogenesis.  相似文献   

6.
贵州布依族、仫佬族和毛南族9对遗传性状的基因频率   总被引:1,自引:0,他引:1  
对贵州布依族、仫佬族和毛南族1239例的9对遗传性状的基因频率进行了调查, 并对民族间基因频率差异进行显著性检验。结果显示: 卷舌和小指弯曲的显性基因频率高于隐性基因频率, 而叠舌、前额发际、发旋、耵聍、拇指类型、中指毛、环食指长则相反; 卷舌、叠舌、前额发际、耵聍、拇指类型、环食指长的基因频率在民族间差异较大, 而发旋、中指毛、小指弯曲则相对较小。  相似文献   

7.
Experiments were carried out to elucidate changes in cytoskeletal elements and intercellular junctions in the organ of Corti, when hair cells degenerate and phalangeal scars form. Hair cell damage was induced by exposing guinea pigs to high intensity noise. The spatial and temporal changes in the organization of microfilaments, intermediate filaments, and tight junction-specific proteins were investigated using scanning and transmission electron microscopy and histochemistry. The results show that microfilaments, cytokeratins, adherens junctions, and tight junctions rearrange their distribution in damaged areas. From the temporal sequence of these changes it appears that phalangeal scars develop simultaneous with hair cell degeneration, and that the integrity of the luminal membranes in the organ of Corti is not interrupted. Each scar is formed by two supporting cells which expand and invade the sub-apical region of the dying hair cell. This region becomes cytokeratin-positive. The two supporting cells meet at the mid-line of the scar, where a new junctional complex is formed. The junctional complex consists of tight junction and adherens-type junction, but desmosomes are absent.  相似文献   

8.
Middle phalangeal hair was found to be present in 71% if Saudi Arabian males. For those exhibiting this trait, the frequency of combinations of digits with hair was similar to the frequency in other populations.  相似文献   

9.
长久以来,指骨弯曲程度都被用来推断化石灵长类移动行为方式。此前已有一些方法被提出并用于定量化比较指骨弯曲程度,包括半径弯曲程度法(radius of curvature)、夹角法(included angle, IA)、标准化矩臂弯曲程度法(normalized curvature moment arm, NCMA)以及高精度多项式曲线拟合法(high-resolution polynomial curve fitting, HR-PCF)。然而,在对指骨弯曲程度进行定量化的过程中,这些方法都显示出了理论或技术上的局限性。因此,在运用这些方法之前,应当谨慎考虑其适用性和精确程度对分析结果所产生的影响。鉴于此,为了避免先前方法中存在的问题并更加精确地定量描述指骨弯曲程度,本文介绍了一种新方法作为替代。该方法基于对指骨侧视图背侧轮廓曲线几何形态测量学标志点数据的四阶多项式曲线拟合,称为几何形态测量学—多项式曲线拟合法(4th order polynomial curve fitting on geometric morphometric landmark data, GM-PCF)。它以标准化指骨曲线高度(normalized phalangeal curve height, NPCH)作为指骨弯曲程度的定量指标,并且可以将平均标准化指骨曲线进行可视化以用于其弯曲程度的直观对比。此外,它还可以提供在解释指骨弯曲程度的功能意义中非常关键的指骨(背侧轮廓曲线)长度比例信息。GM-PCF还能够分析化石中常见的不完整的指骨。为了检验新方法的适用性,我们从现生类人猿(anthropoids)中选取了15个涵盖灵长类大部分移动行为方式的类群作为参考样本,采用GM-PCF方法对其指骨弯曲程度进行了定量分析,结果表明标准化指骨曲线高度(NPCH)对灵长类移动行为方式有很好的指示意义,配合指骨曲线长度,还可以更进一步了解树栖四足行走(arboreal quadrupedalism)、悬垂(suspension)与摆荡(brachiation)等行为与灵长类体型大小的关系。作为个案,我们采用新方法对中国中新世的两种禄丰古猿(禄丰禄丰古猿Lufengpithecus lufengensis和蝴蝶禄丰古猿Lufengpithecus hudienensis)的指骨弯曲程度与参考样本进行了对比,并根据对比结果对其最为可能的移动行为方式偏好进行了推断。  相似文献   

10.
11.
According to the generally accepted theory of mammalian cochlear mechanics, the fluid in the cochlear scalae interacts with the elastic cochlear partition to generate transversely oscillating displacement waves that propagate along the cochlear coil. Using a computational model of cochlear segments, a different type of propagating wave is reported, an elastic propagating wave that is independent of the fluid-structure interaction. The characteristics of the propagating wave observed in the model, such as the wavelength, speed, and phase lag, are similar to those observed in the living cochlea. Three conditions are required for the existence of the elastic propagating wave in the cochlear partition without fluid-interaction: 1), the stiffness gradient of the cochlear partition; 2), the elastic longitudinal coupling; and 3), the Y-shaped structure in the organ of Corti formed by the outer hair cell, the Deiters cell, and the Deiters cell phalangeal process. The elastic propagating waves in the cochlear partition disappeared without the push-pull action provided by the outer hair cell and Deiters cell phalangeal process. The results suggest that the mechanical feedback of outer hair cells, facilitated by the organ of Corti microstructure, can control the tuning and amplification by modulating the cochlear traveling wave.  相似文献   

12.
According to the generally accepted theory of mammalian cochlear mechanics, the fluid in the cochlear scalae interacts with the elastic cochlear partition to generate transversely oscillating displacement waves that propagate along the cochlear coil. Using a computational model of cochlear segments, a different type of propagating wave is reported, an elastic propagating wave that is independent of the fluid-structure interaction. The characteristics of the propagating wave observed in the model, such as the wavelength, speed, and phase lag, are similar to those observed in the living cochlea. Three conditions are required for the existence of the elastic propagating wave in the cochlear partition without fluid-interaction: 1), the stiffness gradient of the cochlear partition; 2), the elastic longitudinal coupling; and 3), the Y-shaped structure in the organ of Corti formed by the outer hair cell, the Deiters cell, and the Deiters cell phalangeal process. The elastic propagating waves in the cochlear partition disappeared without the push-pull action provided by the outer hair cell and Deiters cell phalangeal process. The results suggest that the mechanical feedback of outer hair cells, facilitated by the organ of Corti microstructure, can control the tuning and amplification by modulating the cochlear traveling wave.  相似文献   

13.
Non-sensory cells in the deafened organ of Corti: approaches for repair   总被引:1,自引:0,他引:1  
After moderate cochlear trauma, hair cells degenerate and their places are taken by phalangeal scars formed by differentiated supporting cells. A short time after trauma, these supporting cells can respond to an induced expression of genes which signal hair cell differentiation during normal development and transdifferentiate into new hair cells. However, these non-sensory cells often lose their differentiated features after severe insults or prolonged hearing loss and become a simple, flat epithelium. The flat organ of Corti can serve as a substrate for gene- and stem cell-based therapies. Despite its prevalence, the flat epithelium is not well characterized. Recent data show that cells of the flat epithelium can divide and maintain the structural confluence of the membranous labyrinth. The mitotic potential of these cells should facilitate production of cells for therapies based on recapitulation of development or insertion of stem cells.  相似文献   

14.
Phenotype and gene frequencies of two blood group and four red cell enzyme systems were examined in a Konda Kapu tribal sample of Coastal Andhra Pradesh, South India. The gene frequencies for these systems in Konda Kapus indicate the middle range values for Andhra Pradesh tribal populations, excepting the ADA and Rh(D) systems, where extreme range values are found. Further, gene flow is indicated between the Konda Kapus under study and Plain Kapus, a neighbouring caste population by calculation of Fi estimates.  相似文献   

15.
Root hairs are an excellent model system to study cell developmental processes as they are easily accessible, single-celled, long tubular extensions of root epidermal cells. In a genetic approach to identify loci important for root hair development, we have isolated eight der (deformed root hairs) mutants from an ethylmethanesulfonate (EMS)-mutagenized Arabidopsis population. The der lines represent five new loci involved in root hair development and show a variety of abnormalities in root hair morphology, indicating that different root hair developmental stages are affected. A double mutant analysis with the short root hair actin2 mutant der1-2 confirmed that the der mutants are disturbed at different time points of root hair formation. Auxin and ethylene are known to be important for trichoblast cell fate determination and root hair elongation. Here, we show that they are able to suppress the phenotype of two der mutants. As the auxin- and ethylene-responsive der mutants are affected at different stages of root hair formation, our results demonstrate that the function of auxin and ethylene is not limited to cell differentiation and root hair elongation but that the two hormones are effective throughout the whole root hair developmental process.  相似文献   

16.
Nowadays research and clinical studies of human reproductive endocrinology are generally carried out using human blood reproductive hormone assays. However the acquisition of human blood samples has some shortcomings. In search of new approaches, we paid attention to the fact that progesterone can be detected in cow's hair. Consequently we investigated whether or not steroid hormones are measurable in human hair. The results showed that the levels of steroid hormones in hair are not affected by shampoo and do not significantly vary between different segments of hair (i.e. top, middle and basal segments). The menstrual estradiol and progesterone rhythm of female hair is similar to that of female serum. The ratio of hair estradiol to serum estradiol in the female is 41.2% and that of hair progesterone to serum progesterone is 59.0%; the ratio of hair testosterone to serum testosterone in male is 116%. There are significant correlations between hair and serum steroid hormones of healthy human adult: γ (estradiol)=0.395 (n=20), p<0.05; γ (progesterone)=0.440 (n=22), p<0.025 and γ (testosterone)=0.395 (n=25), p<0.05.  相似文献   

17.
Summary HLA A and B antigens have been determined in 2740 adult responders to a population health survey in Busselton, Western Australia. HLA A B and C antigens have been determined in 481 schoolchildren. The antigen frequencies are generally close to those obtained elsewhere for subjects of British origin, but there are some differences from the frequencies found in North American Caucasians. The frequencies were not affected by the inclusion of genetically related individuals in the sample. Seventeen HLA A-B haplotypes, six A-C haplotypes and six B-C haplotypes had frequencies above 1%. A total of 1071 distinct phenotypes were identified out of the 5069 which are theoretically possible for the HLAA-B model used in the study. The most frequent phenotype was A2, B12 which occurred in 2.5% of the sample.  相似文献   

18.
The occurrence of brachymesophalangia-V (BMP-V) in 2,012 individuals from five samples of children of different ethnic backgrounds was determined using two indices. Frequencies of BMP-V were analyzed for three variants: BMP-V alone, BMP-V with clinodactyly, and BMP-V with a cone-shaped epiphysis. The two indices used to identify BMP-V indicated highest relative frequencies among Mexican children, moderate frequencies among children of European ancestry (Pennsylvania White, Canadian, West German), and lower frequencies in Pennsylvania Black children. Index 1, based on the ratio of the width to the length of the fifth mid-phalanx, consistently produced higher frequencies than Index 2, based on the ratio of the length of the fifth to the length of the fourth midphalanges. Index 1 was also more selective of BMP-alone, while Index 2 selected primarily BMP-V with clinodactyly and/or cone-shaped epiphyses. The differences between indices were largely due to the fact that Index 1, which basically defines shape, selected both the shortest and/or widest mid-phalanges, while Index 2 related actual length differences. It is suggested that Index 2 provided a more suitable criterion of BMP-V in comparative studies, due to possible population differences in phalangeal shape.  相似文献   

19.
20.
This article examines the curvature of the manual proximal and middle phalanges of species belonging to Pan, Gorilla, Ateles, Macaca, Pongo, Hylobates, and Cebus to determine whether middle phalangeal curvature, when considered in conjunction with proximal phalangeal curvature, yields a locomotor signal. Prior studies have demonstrated the discriminatory power of proximal phalanges for separating suspensory species (including knuckle walkers) from pronograde quadrupedal species, but less emphasis has been placed on the distinguishing phalangeal characteristics of taxa within the suspensory category. This study demonstrates, first, that middle phalanges discriminate suspensory from nonsuspensory species, although not as cleanly as proximal phalanges. Finer discrimination of locomotor signals, including subtle differences among animals employing different modes of suspension, is possible through a comparison of the curvatures of the proximal phalanges and corresponding middle phalanges. Their relative curvature differs in quadrupeds, brachiators, and knuckle walkers. Knuckle walkers (Pan and Gorilla) have relatively little curvature of the middle phalanges coupled with marked curvature of the proximal phalanges, whereas brachiators (Ateles and Hylobates) display marked curvature of both proximal and middle phalanges, and pronograde quadrupeds (Cebus and Macaca) have relatively straight proximal and moderately curved middle phalanges. Quadrumanous climbers (Pongo) have a unique combination of traits, whereby curvature is high in both proximal and middle phalanges, but less so in the latter than the former. These differences, predictable on the basis of the biomechanical forces to which digits are subjected, may open a new venue for future research on the locomotor repertoire of prebipedal ancestors of hominins.  相似文献   

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