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1.
The growth of the 19 tubular hand bones from fetal months 5 to 9 was studied by the allometric method. The hand bones were carefully dissected under a low power stereoscopic microscope. The length and breadth of all bones was found to be monophasic in relation to crown-rump length. In general, maximum bone and ossified shaft lengths in the same row group demonstrate similar allometric coefficients. The specific growth rate of ossified shaft length for all fetal hand bones is greater than the growth rate of maximum length. The highest allometric coefficients for both maximum length and ossified shaft length were obtained from the middle phalanges. The shape of the metacarpals and distal phalanges becomes thinner, while the other bones become thicker or maintain their length-breadth ratio. The relative growth pattern of the first proximal phalanx differed from the middle phalangeal group of the other digits. This suggests that current nomenclatures for the three bones of the pollex is appropriate.  相似文献   

2.
A survey of hominid hand and wrist bones of Plio-Pleistocene fossil hominid sites in Africa was undertaken. There are 101 specimens in total, from 7 sites. Carpals are most rarely preserved, but certain elements such as the capitate tend to be more frequently preserved than others. There is a preservation rate cline from proximal to distal in the hand, proximal elements (metacarpals) being numerically better preserved than the distal elements (proximal, middle and distal phalanges, in that order of preservation). The proportion of complete, or nearly complete hand and wrist bones is greater in the distal than in the proximal elements. There is no statistical difference in the frequency of preservation of left and right sides, or in the frequency of preservation of proximal and distal ends of individual bones, although there is a tendency for proximal ends to occur more frequently than distal ends. The incidence of hand and wrist bones in fossil deposits is low compared with that of other post-cranial skeletal elements (with the exception of foot bones, where the incidence is similar). This could be accounted for by depositional factors, but preparation techniques and differential collection of specimens may play a role.  相似文献   

3.
Serial radiographs of the hand-wrist were used to analyze the associations within bones between the rates of change in skeletal maturity, diaphyseal and epiphyseal lengths and diaphyseal width. In previous studies of these children, it has been shown that these rates are linear in relation to chronological age. The associations between the rates of change in these parameters were analyzed using the slopes (b values) for regression lines flitted to the data in each child. In individual bones, most of the correlation coefficients were moderate to low; some were negative. For most associations in each sex they were relatively high for metacarpal II. The rates of skeletal maturation and diaphyseal elongation were correlated more highly in the girls than in the boys but the rates of skeletal maturation and epiphyseal elongation were correlated more highly in the boys. When bones were considered in groups, relatively high correlations were noted for the metacarpals and ray II, lower correlations were common for the middle and distal phalanges. There was no evidence of real neighborhood effects but marginal effects were present.  相似文献   

4.
Communality indices for rates of elongation of diaphyses of short bones of the hand were computed from serial data for children with Down syndrome, 7 to 14 years of age. Communalities were larger for adjacent than for nonadjacent bones and also larger for bones grouped in rows rather than rays of the hand. This pattern is similar to that reported for normal children. Communality indices for rates of diaphyseal elongation for girls with Down syndrome were lower than those of boys with Down syndrome and normal children.  相似文献   

5.
B. Hughes 《Journal of Zoology》1968,156(4):457-481
A new reconstruction of the tarsus of Stenaulorhynchus stockleyi differs from that previously offered by von Huene (1938) and Schaeffer (1941), and leads to a revaluation of the tarsi of other rhynchosaurs and rhynchocephalians. The tarsi of the rhynchosaurs Stenaulorhynchus, Scaphonyx, Cephalonia, Rhynchosaurus, Hyperodapedon, Howesia and Mesosuchus appear to comprise a proximal row of three bones (tibiale, intermedium, and fibulare) and a distal row of three bones associated with metatarsals–4. The metatarsals increase in length but decrease in thickness from the first to fourth, and the fifth is "hooked". The first metatarsal of Stenaulorhynchus, Scaphonyx , and Rhynchosaurus is unusually short. Among the remaining rhynchocephalians, the tarsi of claraziids and pleurosaurids are simplified in accord with aquatic habits involving the use of the limbs as paddles, and those of sphenodontids and Sapheosaurus are alike in the following respects. An astragalus (intermedium+tibiale+ centrale) and calcaneum (fibulare), or a single conjoined bone, occupy the proximal row of the tarsus and the distal row comprises four (first to fourth), three (second to fourth), or but two (third and fourth) bones; the fourth is the largest. The metatarsals increase in length from first to fourth but do not decrease in thickness. In both rhynchosaurian and spheno-dontid types tarsal movement is largely mesotarsal, a condition derived from their eosuchian ancestors and not independently developed as Schaeffer (1941) has thought. The specialization of the sphenodontid tarsus parallels that seen in lizards which have the same eosuchian ancestry.  相似文献   

6.

Background

Stepping over an obstacle is a kind of compound movement that makes walking more difficult, especially for preschool children. This study examines sex and age-level differences in walking time in preschool children on an obstacle frame.

Methods

The participants included 324 healthy preschool children: four-year-old boys (51) and girls (51), five-year-old boys (50) and girls (60), and six-year-old boys (62) and girls (50). A 5 cm- or 10 cm-high obstacle (depth 11.5 cm, width 23.5 cm) was set at the halfway point of a 200 cm × 10 cm walking course.

Results

The participants walked to the end of the course and back as fast as possible under three conditions: no obstacle, low obstacle and high obstacle. Walking time showed age-level differences in all conditions, but there were no differences in sex. Age levels were divided into two groups, with one group within the first six months of their birthday, and the second group within the last six months of that year. Walking time for children in the first half of their fourth year was longer than that of the five- and six-year-old children. In addition, for children in the last half of their fourth year, walking time was longer than both sexes in the last half of their fifth and sixth years. The children in the latter half of their fifth year had a longer walking time in the high obstacle condition than those in the last half of their sixth year. In the four-year-old participants, walking time was shorter with no obstacles than with a high obstacle frame.

Conclusions

In the above data, obstacle course walking time does not show a gender difference, except that the four-year-old participants needed longer than the five- and six-year-old children. Setting the obstacle 10 cm high also produced a different walking time in the five- and six-year-old participants. The high obstacle step test (10 cm) best evaluated the dynamic balance of preschool children.  相似文献   

7.
Data from serial radiographs of 40 children were used to study the rates of total, diaphyseal and epiphyseal elongation of the bones of the hand from 3–13 years. Communality indices were calculated from complete correlation matrices for each sex. These indices tended to be lower for boys than girls. Communality indices for distal phalanges were lower than for the other bones and those for epiphyseal elongation were lower than those for total or diaphyseal elongation. Correlations between groups of bones in their rates of elongation were higher in rows of bones than in rays. There were statistically significant neighborhood effects and a slight tendency to marginal effects in the correlations between rates of elongation in rows of bones; neither of these effects was present in rays.  相似文献   

8.
Natural markers in bone growth   总被引:1,自引:0,他引:1  
Three features in the long bones, shown by radiograms, have been used as markers for the study of bone growth.
  • (I) Transverse lines of arrested growth. Radiograms of six long limb bones from 1,576 individuals were investigated for clearness and persistence of these lines. Both ends of tibia and fibula showed very high frequency of suitable lines for markers, possibly also the distal end of femur and radius.
  • (II) Notches in the base of second and fifth metacarpal bones. Measurements of growth from apex of the basal notch to the ends of the shaft were performed on serial hand radiograms. The proportion of growth from distal and basal ends averaged 87:13 in the second and 80:20 in the fifth metacarpal bones.
  • (III) Nutrient canals. The initial point of ossification was determined by a prolongation of the nutrient canal intersecting the central axis of the medullary cavity. The proportion of growth from that point to distal and basal ends of the shaft averaged 68:32 and 64:36 for the second and the fifth metacarpal bones, respectively. These values are significantly different from the measurements obtained from the notches.
  相似文献   

9.
达斡尔族学生皮下脂肪发育的研究   总被引:25,自引:3,他引:22  
作者内蒙古莫力达瓦达斡尔族自治旗1759例中小学生项项皮褶厚度及体脂发育情况进行了调查研究。结果表明:(1)达斡尔族学生进入青春期后,随着年龄的增长,男性躯干部皮变厚,四肢部皮褶变薄,女性躯干、四肢部皮褶均增厚。(2)12岁后,女性皮褶厚度显著大于男性。(3)青春发育早期,男性体脂逐渐有下降,女性于12-14岁体脂迅速增加。(4)总体说来,达斡尔族学生并不偏于肥胖。  相似文献   

10.
Serial annual radiographs of the hand have been used to analyze the rates of elongation of the epiphyses and diaphyses of the metacarpals and phalanges in children at ages from 3 to 13 years. The rates of elongation for many corresponding ephiphyses and diaphyses (i.e., of the same bone) are negatively correlated but to an extent that is not statistically significant for any particular bone. This tendency toward negative correlations is found for most of these bones although the correlation coefficients for most of the metacarpals are positive in each sex. Within rays, the correlation indices between the rates of elongation for corresponding epiphyses and diaphyses (i.e., of the same bone) have larger negative or smaller positive values than for those between either adjacent and non-corresponding or non-adjacent and non-corresponding epiphyses and diaphyses (i.e., not of the same bone but of either adjacent or non-adjacent bones). The communality indices for the ratio between the rates of epiphyseal and diaphyseal elongation in particular bones are more highly correlated in the girls than in the boys and within the rows than within the rays. Some implications of the tendency to negative correlations between the rates of elongation of corresponding epiphyses and diaphyses have been discussed.  相似文献   

11.
12.
The determination of physiologic lower limb functional imbalance among healthy teenagers is important to follow the rehabilitation progress and return to normal activity of injured subjects. We investigated the differences in vertical jump capacity between both legs in a group of healthy boys and girls, considering the performances in the dominant vs. non-dominant, and in the most vs. least efficient leg. Strength and power performances were compared in 117 boys and 106 girls aged 10-16 years during a single-leg vertical countermovement jump (SLVCJ) test. When leg dominance was defined subjectively by the participant, no difference was noted between the 2 legs. Statistically significant differences were recorded between the most and less efficient leg in strength and power performances for both genders. Girls had significantly greater peak strength than did age-matched boys, but boys showed significant increases in maximal power outputs compared with that shown by age-matched girls. When the results were analyzed according to the percentage of participants falling within certain bands of limb asymmetry, approximately 20-30% showed a difference of >15% between the 2 limbs without any relation to gender. Subjective expression of leg dominance cannot be used as a predictor of SLVCJ performance. Differences of <15% in SLVCJ performance between both legs should be considered as the physiological norm in this age group. A greater appreciation of the potential diagnostic value of the SLVCJ test may be obtained if the results are interpreted in terms of the percentage of subjects falling within certain bands of limb asymmetry. Gender-based differences in the SLVCJ test vary and depend upon whether the results are interpreted in terms of strength or power output.  相似文献   

13.
Blood and saliva were collected in the autumn and spring from a group of schoolchildren (39 girls, 35 boys) with a mean age of 11.4 years. Serum immunoglobulin IgG, IgA, IgM and IgE, alpha 1-antitrypsin (A 1-AT), alpha 2 macroglobulin (A 2M), transferrin (TRF), ceruloplasmin (CPL), lysozyme (LYS) and pertussis (PE) antibody levels were determined. Calcium (Ca2+) and total serum protein levels were also determined. Secretory IgA (sIgA) and secretory lysozyme (sLYS) levels were assessed in the saliva. A highly significant drop in Ca2+ levels was found in the spring in boys, while in girls there was only a greater scatter of the values. Mean IgG, IgA and IgM values fell significantly in the spring in both sexes, but IgE levels fell significantly only in boys. PE levels rose significantly in the spring in girls. Among the other proteins, all the values rose in boys, except for TRF, whose levels fell. In girls, LYS and TRF levels rose, but all the other values fell. The coefficients of correlation between Ca2+ and the tested proteins showed a significant relationship only for A 2M and PE in girls and only for the total protein level in boys; in boys, the determination coefficient for sIgA and IgM was over 10%. The results do not testify to the existence of a close relationship between blood Ca2+ levels and Ig and other blood protein levels.  相似文献   

14.
从中指骨长度推算身高的研究   总被引:2,自引:0,他引:2  
朱芳武 《人类学学报》1983,2(4):375-379
作者对近年在华南地区收集的,已知生前身高的汉族成年男性骨骼的中指骨近节、中节进行了测量。用直线回归方程、多元回归方程对从中指骨长度推算身高进行了研究。并用50例国人骨骼标本对这些推算身高的方法作了检验。结果表明,中指骨与四肢大型长骨,以及从中指骨长度推算身高的直线回归方程与多元回归方程,对推算身高的价值都是相同的。  相似文献   

15.
Skeletal maturation rates for the age interval 3 to 13 years were analyzed using bone-specific assessments (Greulich-Pyle) of serial radiographs of 40 children. The mean rates of skeletal maturation resembled those of the population from which the atlas standards had been derived. There was a linear trend of skeletal age against chronological age for most bones in each sex. Regression lines were fitted to these data and the b values of the regression lines were calculated. Communality indices were calculated from an intercorrelation matrix of these b values. There was a statistically significant rank order correlation between the sexes in the communality indices. They tended to be higher in the girls than in the boys and were relatively low for the radius, ulna and carpals. Communality indices within groups of bones were high in all rows, especially the metacarpals, but in each sex they were comparatively low in the first ray (metacarpal plus the phalanges of the corresponding digit) and in the fifth ray of the boys. Neighborhood effects on the levels of association of maturation rates were present, particularly in the carpus, but marginal effects were not noted.  相似文献   

16.
By antropometry and roentgenography methods in 52 twin pairs of different sex, body dimensions, the third metacarpal bone and the phalange of the third right hand finger, as well as the terms of permanent teeth eruption were studied. The investigation revealed no timely coincident periods in growth activity between girls and boys. During the first period (6,5--10 years), predominance of some dimentions is observed in boys, during the second (8,5--14 years)--in girls, and during the third (11--17 years)--in boys again. Somewhat different terms for permanent teeth eruption make it possible to distinguish two periods: 7 years when the boys surpass the girls in the number of permanent teeth (two teeth in average) and 8--14 years when the boys lag behind the girls in the number of permanent teeth.  相似文献   

17.
The present study investigated the impact of puberty on sex differences in neural sensitivity to negative stimuli. Event-related oscillation technique was used. Because girls are more vulnerable to affective disturbances than boys during adolescence, it was hypothesized that puberty exerts different influences on neural sensitivity to negative stimuli in boys and girls. EEGs were recorded for highly negative (HN), mildly negative (MN) and neutral pictures, when boys and girls distinct in pubertal status performed a non-emotional distracting task. No emotion effect and its interaction with sex and puberty were observed in response latencies. However, puberty influenced the gamma-band oscillation effect for negative stimuli differently for boys and girls: Pre-pubertal boys showed a significant emotion effect for HN stimuli, whose size was decreased in pubertal boys. By contrast, there was a significant emotion effect for HN stimuli in pubertal girls but not in pre-pubertal girls. On the other hand, the size of the emotion effect for HN stimuli was similar for pre-pubertal boys and girls; while this effect was significantly more pronounced in pubertal girls compared to pubertal boys. Additionally, the size of the emotion effect in gamma oscillations decreased as a function of pubertal development during both HN and MN stimulation in boys. For girls, the emotion effect in gamma oscillations increased with pubertal development during HN stimulation. Thus, puberty is associated with reduced neural sensitivity in boys but increased sensitivity in girls, in reaction to negative stimuli. The implications of these results for the psychopathology during adolescence were discussed.  相似文献   

18.
The rate of growth in height and the timing of adolescent growth events are analyzed for two samples of Guatemalan children. One sample includes Mayan school children, 33 boys and 12 girls between the ages of 5.00 to 17.99 years, living under poor conditions for growth and development. The second sample includes ladino children, 78 boys and 85 girls of the same age range, living under favorable conditions for growth. The Preece-Baines model I function is used to estimate mean values for rates and timing of childhood and adolescent growth events for the two groups. Significant statistical contrasts (t-tests) of these means show Mayan boys reach the age of "take-off" (TO; the onset of the adolescent growth spurt) 1.45 years later, achieve peak height velocity (PHV) 1.68 years later, and continue growing for about 2.0 years longer than do the ladino boys. Despite the Mayan boys' increased duration for growth they grow significantly more slowly than the ladinos. Mayan boys are 6.60 cm shorter than ladinos at the age of TO and are estimated to be 7.71 cm shorter than the ladinos at adulthood. Mayan girls reach the age of TO 0.93 years later than do the ladina girls, but the two groups do not differ in the age at PHV or the age at adulthood. The mean height of Mayan girls is significantly less than that of ladinas at the age of TO (6.5 cm), and this difference increases to an estimated 11.14 cm at adulthood. Possible causes of these ethnic and sex-related differences in amounts and rates of growth are discussed in relation to hypotheses about the genetic and environmental determinants of human development.  相似文献   

19.
Transverse lines on the distal tibia, transiently present in 90% of boys and girls, afford the possibility of measuring localized bone growth, proximal and distal, epiphyseal and diaphyseal, and their relative and shifting contributions to total bone growth in children followed in longitudinal fashion.  相似文献   

20.
A cross sectional study of the physical growth status was made on 655 Kamar children (341 boys and 314 girls), aged 5 to 18 years, in the Raipur district of Chhattisgarh. The study aimed to find out the growth pattern of the Kamar children, which is considered to be a primitive tribe of Chhattisgarh, India and was compared with another Indian tribe and the official data for all India (ICMR). Anthropometric measurements included height, weight, sitting height, biacromial diameter, biilliocrystal diameter, upper arm circumference, calf circumference and measurements of the triceps and subscapular skinfolds. All anthropometric measurements except skinfold thickness exhibit uniform increase with age in both sexes. However, when height and weight of the Kamar boys and girls were compared with the data for other tribes and for all India, the Kamar children (both boys and girls) indicated lower weight and height and the difference showed to be significant, for almost all ages. Kamar boys showed higher anthropometric values than girls in almost all measurements except in biilliocrystal diameter and in measured skinfolds. Poor socio-economic status of this primitive tribe may be one of the reasons for this poor growth pattern. However, in-depth study is necessary in order to arrive at any basic conclusions and to recommend any policy and interventions.  相似文献   

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