胫骨判定性别的逐步判别分析

西安地区现代成人男女各50例的胫骨,进行12项测量,用逐步判别分析的方法进行研究。其结果:仅用下段宽判定性别,准确性达71％;而用下段宽,下段矢径和滋养孔平面最大矢径判定性别,准确性可达77％。并将该结果与美国白人和黑人的有关资料进行了对比。     

胫骨中段横断面与年龄变化的研究

本文对218例1—94岁中国汉族人胫骨中段横断面的矢状径、横径、髓腔矢、横径及骨密质前、内、外缘,内、外、后面厚度等10项指标进行了测量分析。结果表明,胫骨中段矢状径、横径及骨密质相对厚度在1—30岁年龄阶段与年龄具有高度正相关性。髓腔平均直径在1—25岁年龄阶段亦呈规律性变化。     

太行山猕猴第Ⅶ颈椎变量的异速生长分析

以肱骨最大长为参照,对成年太行山猕猴第Ⅶ颈椎变量进行了异速生长分析。结果表明,椎体后高、椎体上矢径、全宽呈正异速生长;椎体下横径接近等速生长;椎体前高、椎体下矢径、椎体上横径、椎孔矢径、椎孔横径、矢径呈负异速生长。     

国人胫骨的测量及其性别差别分析

为积累国人资料,本文对长春、通辽两地出土的１２７副胫骨（男７１,女５６）进行了胎骨大长、胎骨全长等２６项指标的测量,计算出胫骨中部断面指数和胎骨指数等４项指数及其分型,进行了侧别、性别及地区比较,并用胫骨最大长等７项因素进行了Ｆｉｓｈｅｒ法性别判别分析,得出５个判别式。结果显示：除个别测量项外均无显著性侧别差异,但均具有显著性性别差异,部分项目存在显著性地区差异;判别分析中判别正确率,介于美国白人     

从X线片研究不同类型的体育运动对胫骨内、外径的影响

本文对45名男少年(依其从事运动情况分为举重、跳跃组,不从事专项运动者为普通组)胫骨正位和侧位X线片进行了观察、测量,并对三组胫骨的髓腔径、内外横径比和内外矢状径比等指标进行了统计分析。结果表明:不同机能对髓腔大小的影响既在某些方面相似,又在另一些方面出现不同的趋势;对内外径比的某些方面也有不同影响;内外径比变化趋势并非国外某些学者所记载的以8:11最为适宜。     

国人胫骨的测量及其性别判别分析

为积累国人资料,本文对长春、通辽两地出土的１２７副胚骨（男７１,女５６）进行了胚骨最大长、胚骨全长等２６项指标的测量,计算出胫骨中部断面指数和胚骨指数等４项指数及其分型,进行了侧别、性别及地区比较,并用胫骨最大长等７项因素进行了Ｆｉｓｈｅｒ法性别判别分析,得出５个判别式．结果显示：除个别测量项外均无显著性侧别差异,但均具有显著性性别差异,部分项目存在显著性地区差异;判别分析中判别正确率（７８．３％－８２．３％）介于美国白人与黑人之间。     

寰椎的测量、相关与性别判别分析

本文对85例(男46,女39)国人寰椎进行了四项测量,其性差均非常显著,但两性重迭率≥38.9％。另算出两项指数,其性差不显著。从中挑选全宽(X_1)和矢径(X_2)两个变量经计算得判别式Z=X_1+2.21098x_2,临界值Z_0=172.9102。经组内外回代误判率分别为18.5％和12.9％。对四项测量作了相关分析,其中寰椎矢径与椎孔横径、全宽与椎孔矢径均呈中度正相关。并用寰椎矢径(X_2)推算椎孔横径(y),其男性Y=18.01±0.2579X_2,女性Y=4.88±0.5505X_2。     

中国汉族男性腰椎的身高推断

本文研究了中国汉族男性腰椎的测量及腰椎推断身高的方法。测量指标有 :椎体前高、椎体后高、椎体上矢径、椎体下矢径、椎体上横径、椎体下横径、椎体中部横径、椎孔矢状径、椎孔横径、左侧椎弓根厚度。将各腰椎的测量数据与身高进行了相关分析并建立了中国汉族男性腰椎推断身高的回归方程。本研究所建立的方程 ,可以用于中国汉族男性腰椎的身高推断。     

快速扩弓前方牵引矫治替牙期骨性反合效果的CT观察

目的:应用CBCT观察快速扩弓前方牵引矫治替牙期骨性安氏Ⅲ类错合对上气道的影响。方法:选取替牙期骨性安氏Ⅲ类错合患者22例,采用上颌快速扩弓前方牵引治疗,应用CBCT评估矫治前后上气道的大小和形态的变化。结果:替牙期骨性安氏Ⅲ类错合患者矫治后上气道的总体积、腭咽、舌咽、喉咽及口咽体积显著增大(P0.05);软腭尖、会厌顶平面上气道的截面积及口咽段最小截面积、软腭尖平面矢状径、横径与会厌顶平面横径均显著增大(P0.05);硬腭平面的截面积、横径与矢状径及会厌平面的矢状径无显著变化(P0.05)。软腭尖平面上气道的矢横径比显著增大,会厌顶平面的矢横径比显著减小(P0.05)。结论:快速扩弓前方牵引矫治替牙期骨性安氏Ⅲ类错合患者后上气道变大。     

珠江口棘头梅童鱼耳石的生长特性

研究了棘头梅童鱼(Collichthys lucidus)耳石的形态参数、生长特性及其与鱼体生长的关系,选用左矢耳石为研究对象,用直线、对数、多项式、幂函数和指数函数拟合矢耳石各参数的生长关系式,依据耳石日轮鉴定了日龄。结果表明,体长范围为29.8～104.0 mm的棘头梅童鱼矢耳石的长直径随鱼体生长而增大,但短直径与长直径的比值以及长直径方向上的短半径与长半径的比值则基本稳定。矢耳石的长、宽和重之间,以及长半径和短半径之间均呈显著的幂函数相关关系;矢耳石生长与鱼体生长的关系中,矢耳石长、宽、厚、重与长半径和体长、体重之间的关系,除了体长与耳石厚的关系为显著的二次多项式外,全部呈显著的幂函数相关关系。     

中国汉族髋骨的性别差异和判断

本文研究乌鲁木齐市附近出土的汉族达到成年尺寸的正常髋骨(男115块,女54块,性别主要借助骨盆形态来判断)。测量了耻骨长、坐骨长、髋臼径及坐骨大切迹宽、深等八个项目。列表和图显示了各项数据的分布。利用这些图表可以帮助鉴别中国汉人髋骨的性别。经统计方法检验,这些特征在性别和人种之间有非常显著或显著的差异,汉人与美国白人及爱斯基摩人较接近。     

Sex differences in the relative lengths of metacarpals and metatarsals in gorillas and chimpanzees

Sex differences other than the simple dimorphism in size were documented for the metapodials of two primate species. Lengths of metacarpals and metatarsals were obtained from the skeletons of 64 gorillas and 42 chimpanzees. Length ratios were constructed for all possible pairings of the five bones in each individual hand and foot. For both species, several of these length ratios exhibited substantial differences between the sexes. Body size was not the basis for these sex differences; when specimens of similar size were compared, the sex differences remained. In humans, length ratios for the fingers and toes also have previously been demonstrated to exhibit sex differences, and the length ratio for the index and ring fingers (the 2D:4D ratio) has been shown to correlate with various medical conditions. Various facts suggest that length ratios in human digits are associated with androgen exposure, probably during prenatal development. For gorillas, the metacarpal length ratio showing the largest sex difference was 4Mc:5Mc in both hands, and the metatarsal length ratio showing the largest sex difference was 1Mt:2Mt in the left foot. Sex differences in length ratios also existed for chimpanzees, but they were generally smaller than for gorillas. Apparently, both gorillas and chimpanzees are affected by developmental mechanisms, possibly androgenic mechanisms, similar to those in humans. Analyses of previous measurements [Susman, R.L., 1979 Comparative and functional morphology of hominoid fingers. Am. J. Phys. Anthropol. 50, 215-236] revealed that all components of the rays are not affected equally by whatever mechanisms are responsible for the sex differences in length ratios.     

Biomechanical factors affecting fracture stability and femoral bursting in closed intramedullary rod fixation of femur fractures

Intramedullary rodding of femur fractures, although a safe and rapidly performed procedure, can result in several complications. If the rod fit is too loose, fracture instability, rod migration, and delayed union may result. If the rod fit is too tight, cracking of the femur may occur during rod insertion. These complications were investigated in terms of geometric and mechanical parameters of the bone-implant system. Results showed that rods of the same nominal size from different manufacturers showed more than twofold difference in flexural rigidity and a threefold difference in torsional modulus. These differences appear to be due to differences in cross sectional shape and wall thickness of the rods. Measurements of pushout force and hoop stress in cadaver femora showed a large difference in pushout force with different rods, and significantly lower forces in distal than in proximal femoral fracture components. Pushout force decreased with fracture component length proximally and dropped to zero in distal components less than 170 mm long. An increase in ream diameter in the distal components of just 1 mm was found to decrease the mean pushout force from 740N to 90N. The most significant variable was found to be anterior offset of the starting hole more than 6 mm from the centerline of the medullary canal which resulted in consistent lifting of the anterior cortex during insertion of the rod.     

CT and radiographic analysis of sagittal profile changes following thoracoscopic anterior scoliosis surgery

ABSTRACT: BACKGROUND: Previous studies report an increase in thoracic kyphosis after anterior approaches and a flattening of sagittal contours following posterior approaches. Difficulties with measuring sagittal parameters on radiographs are avoided with reformatted sagittal CT reconstructions due to the superior endplate clarity afforded by this imaging modality. METHODS: A prospective study of 30 Lenke 1 adolescent idiopathic scoliosis (AIS) patients receiving selective thoracoscopic anterior spinal fusion (TASF) was performed. Participants had ethically approved low dose CT scans at minimum 24 months after surgery in addition to their standard care following surgery. The change in sagittal contours on supine CT was compared to standing radiographic measurements of the same patients and with previous studies. Inter-observer variability was assessed as well as whether hypokyphotic and normokyphotic patient groups responded differently to the thoracoscopic anterior approach. RESULTS: Mean T5-12 kyphosis Cobb angle increased by 11.8 degrees and lumbar lordosis increased by 5.9 degrees on standing radiographs two years after surgery. By comparison, CT measurements of kyphosis and lordosis increased by 12.3 degrees and 7.0 degrees respectively. 95% confidence intervals for inter-observer variability of sagittal contour measurements on supine CT ranged between 5-8 degrees. TASF had a slightly greater corrective effect on patients who were hypokyphotic before surgery compared with those who were normokyphotic. CONCLUSIONS: Restoration of sagittal profile is an important goal of scoliosis surgery, but reliable measurement with radiographs suffers from poor endplate clarity. TASF significantly improves thoracic kyphosis and lumbar lordosis while preserving proximal and distal junctional alignment in thoracic AIS patients. Supine CT allows greater endplate clarity for sagittal Cobb measurements and linear relationships were found between supine CT and standing radiographic measurements. In this study, improvements in sagittal kyphosis and lordosis following surgery were in agreement with prior anterior surgery studies, and add to the current evidence suggesting that anterior correction is more capable than posterior approaches of addressing the sagittal component of both the instrumented and adjacent non instrumented segments following surgical correction of progressive Lenke 1 idiopathic scoliosis.     

Sex differences in the growth of the human bony pelvis

The study of individual patterns of longitudinal growth of the bony pelvic complex reveals the following findings concerning the sex differences in the growth of the bony pelvis. (1) The patterns of growth show the same individual variability and male-female overlap as the adult configuration of pelves. (2) The sex differences in the adult bony pelvis cannot be attributed to the differential response of one bone to sex hormone. (3) Sex differences develop from complicated variations in rates and direction of growth of local areas of the pelvic complex. (4) The superior functional division of the bony pelvis shows only one notable sex difference — the sexual dimorphism of the directional growth of the anterior one-half of the iliac crest. (5) The inferior functional division of the bony pelvis shows numerous local areas of sexually dimorphic growth, but the major sex differences result from the greater lateral migration of the ischia. (6) Of the regions showing definite sexual dimorphism in growth, the pelvic inlet and sciatic notch are the more variable because of their dependency on two separate anatomical systems for their final adult morphological configuration. The subpubic angle and length of the superior pubic ramus are directly associated with only one anatomical system, the enlargement of the pelvic cavity, thus, they show less variability and more definitive sex difference.     

A simple method to determine leaf angles of grass species

There are several very accurate methods to determine leaf angles in closed canopies. However, these are generally very time-consuming or require special equipment. Average canopy leaf angles were derived from simple height and blade length measurements. An exponential relationship between the height/length ratio and the average blade leaf angle was used. The method was tested for two grass species, Dactylis glomerata and Festuca arundinacea, grown under different UV-B levels. The results clearly show that the method is reasonably accurate and able to identify UV-B induced changes in leaf angle. To get these results only 50 measurements of leaf blade height and length were necessary to calculate the allometric relationship, after which 10 length and height measurements from a canopy were used to calculate the average canopy leaf angle.     

Morphometric study of the fetal development of the human hip joint: significance for congenital hip disease.

Hip joints (280) from 140 human fetuses, obtained from abortions and deaths in the perinatal period, were studied. The fetuses ranged from 8.7 to 40 cm in crown-rump length and are believed to be between 12 and 42 weeks in age. The joints were dissected, morphology inspected, and measurements taken of the depth and diameter of the acetabulum, the diameter of the femoral head, length and width of the ligament of the head, the neck-shaft, and torsion angles of the proximal femur. Regression models were fitted to determine which would best predict the growth pattern. Multivariate analysis of variance showed no significant differences between males and females or between the right and left sides. Acetabular depth was shown to be the slowest-growing hip variable, increasing less than fourfold in the period studied. Acetabular indices less than 50 percent indicate a shallow socket at term. Femoral head and acetabular diameter demonstrated a strong relationship (r = 0.860) and in many joints the femoral head diameter exceeded that of the acetabulum. Considerable variability was demonstrated in both femoral angles. The femoral angles showed only low correlation with the other hip variables. These observations indicate that soft tissue structures about the joint must play an important role in neonatal joint stability. The explanation of greater female and left side involvement in congenital hip disease must lie in factors other than growth changes of hip dimensions. Neither angle appears to be a useful indicator of normal joint development.     

The number of sarcomeres and architecture of the M. gastrocnemius of the rat

The aim of this study was to investigate the number of sarcomeres of different regions (proximal, intermediate and distal third) of the M. gastrocnemius of the rat and compare them with in vivo measurements of the length of the most proximal and distal muscle bundles. These lengths were measured with the aid of dividers at the muscle resting length. The number of sarcomeres was calculated from the length of fibres (measured at 20 times enlargement) tested from HNO3-treated muscle and the average sarcomere length (determined from 80 microns samples taken along the fibres every 800 microns). Ten fibres were isolated from each of three regions of six muscles. All muscles showed the smallest number of sarcomeres in the proximal region of the muscle and increasingly higher numbers in the intermediate and distal parts. The number of sarcomeres in the proximal region is significantly (p less than 0.01) smaller than that of the distal region. These results agree with the results of in vivo length measurements of the most proximal and distal bundles (resp. 31 and 36% of the muscle resting length), the former being significantly (p less than .01) smaller. As there is no significant difference (p less than 0.01) in the length of the treated fibres of the three regions it is concluded that HNO3 treatment does affect the fibres of the muscle in the different regions in a non uniform fashion.     

Treadmill vs. floor walking: kinematics, electromyogram, and heart rate

To identify the degree of difference between treadmill and floor walking, kinematic, electromyographic (EMG), and heart rate measurements were recorded in seven normal female subjects during walking at three speeds on the treadmill and on the floor. During treadmill walking, subjects tended to use a faster cadence and shorter stride length than during floor walking. In addition the displacements of the head, hip, and ankle in the sagittal plane showed statistically significant differences between floor and treadmill walking. Average EMG activity was usually greater on the treadmill than on the floor; however, this difference was only significant for the quadriceps. Heart rate was significantly higher during fast treadmill walking than floor walking. In general, treadmill walking was not found to differ markedly from floor walking in kinematic measurements or EMG patterns.