Improved Performance of Hip DXA Using a Novel Region of Interest in the Upper Part of the Femoral Neck: In Vitro Study Using Bone Strength as a Standard of Reference

We tested the hypothesis that bone mineral density (BMD) and bone mineral content (BMC) in proximal human femur specimens in the upper neck region of interest (ROI) and femoral neck axis length (FNAL) provide a significantly better prediction of femoral bone strength than standard ROIs in vitro. BMD and BMC were measured in 110 proximal femur specimens using a standard dual-energy X-ray absorptiometry (DXA) scanner. The analysis included a new ROI in the upper neck as well as the standard ROIs. FNAL was obtained from the scan images. The specimens' failure-load was measured in a mechanical loading device, simulating a fall on the greater trochanter. For the standard ROIs, correlations between failure-load and BMD ranged from R2 = 0.64 (shaft ROI) to R2 = 0.70, p < 0.001 (femoral neck). Prediction of strength by BMD did not significantly differ from those of BMC (R2 ranging from 0.65 to 0.75, p < 0.001). In the upper neck ROI, for both BMD and BMC correlations with failure-load were higher (R2 = 0.76 and 0.81, respectively; p < 0.001). A lower, yet still significant, correlation was found between FNAL and bone strength (R2 = 0.23, p < 0.001). Normalization of failure-load with respect to FNAL did not significantly increase the correlations with densitometric measures. This study provides in vitro evidence indicating that among the ROIs of the proximal femur the newly defined upper neck ROI provides the best prediction of bone strength. Only a weak association was observed between failure load and FNAL.     

按压骨穴调节围绝经期妇女心脏植物神经功能的研究

目的观察按压骨穴对围绝经期妇女心脏植物神经功能的影响。方法设按压骨穴组30例、空白对照组30例。用美国BraemarDL700型动态心电检测仪,检测试验前后的心率变异性(HRV):TF代表总频,LF代表交感神经活性,HF代表迷走神经活性,LF/HF代表交感神经与迷走神经均衡性。结果按压骨穴后4项指标均有显著下降(P<0.01,P<0.05)。空白对照组变化不显著(P>0.05)。骨穴组4项指标的变化率与对照组比较均有显著性差异(P<0.01)。结论按压骨穴有抑制心脏交感神经活性的良性调整作用,此效应具有相对的特异性。     

新生儿骨矿质含量及影响因素的研究

应用双光子及单光子吸收测定技术，检测了９２名出生３ｄ内的新生儿骨矿质含量，其中巨大儿３０名，正常体重儿３２名，低出生体重儿３０名，其孕龄分别是４０．１±０．７、３９．１±１．５和３７．４±１．２孕周。结果表明，巨大儿、正常体重儿、低出生体重儿的全身骨矿质含量分别是１０１．６±２８．８、８５．２±１９．８、５９．９±２７．２ｇ／ｃｍ２，巨大儿骨矿质含量最高，正常体重儿次之，低出生体重儿最低，差异有显著性（Ｐ＜０．０１）。颅骨、肱骨、股骨的骨矿质含量与全身的骨矿质含量有高度的相关性，相关系数分别是０．９４３、０．８７９和０．７４５（Ｐ＜０．０１）。全身的骨矿质含量与出生体重、孕龄及头围有高度相关性，相关系数分别是０．７５５、０．５９６和０．５５６（Ｐ＜０．０１）。提示颅骨、肱骨及股骨的任一部位均可代表全身的骨矿质含量，肱骨是确定全身骨矿质含量较好的部位，新生儿骨矿质含量受出生体重、孕龄及头围的影响较大。     

Mechanical energy absorption in human hand-arm exposed to sinusoidal vibration

Summary A possible basis for risk assessment of human exposure to vibration when using hand-held tools may be to determine the amount of mechanical energy that is absorbed by the hand-arm system. The aim of this investigation was to study the absorption of mechanical energy in the human hand-arm system during exposure to sinusoidal vibration within the frequency range of 20 to 1500 Hz. A handle, specially designed for this type of experiments, was used during the measurements. The influence of various experimental conditions, such as three different hand-arm postures, grip force (25–75 N) and vibration levels (27–53 mm/s_rms), were studied on eight subjects. The outcome clearly shows that the energy absorption properties of the human hand-arm system are more or less dependent on all of the experimental conditions studied, but mainly to the frequency of the vibration stimuli. Furthermore, the results indicate a non-linear relationship between the energy absorbed and all other variables studies.     

Ridge number density: A new parameter for in vivo bone structure analysis

An advanced analysis of the mechanical properties of bone should include information about the microarchitecture of cancellous bone in addition to its density. It has recently been shown that high-resolution quantitative computed tomography and magnetic resonance imaging have the potential to assess such information in a noninvasive way in patients. Both techniques, however, lack sufficient spatial resolution to image the individual trabeculae with true precision. In this work, a new parameter, Ridge number density (RND), is introduced. RND is a measure for the trabecular number, which can be extracted directly from high-resolution three-dimensional (3D) images of patients. We applied the RND technique to a test group of nine healthy, postmenopausal women measured repetitively with a high-resolution 3D peripheral quantitative computed tomography (3D-pQCT) system with 165 × 165 × 165 μm³ voxel size. Simultaneously with the RND determination, the trabecular bone density (TBD) was also assessed in the same volume of interest. The examination site was the distal radius. The intersubject variability of the measured test group was 10.5% for RND and 26.3% for TBD. The root mean square error between first and second examinations (midterm reproducibility) was 1.6% and 1.1%, respectively. RND is determined independently from TBD and pertains to the structure of the cancellous bone. As such, it might add crucial information in cases where bone mass or bone density measurements alone give ambigous results.     

颞耳岩锥长轴方向的确定和应用

用头颅表面两个标志点确定岩锥长轴方向，指导梅氏（Ｍａｙｅｒ）位和斯氏（Ｓｔｅｎｖｅｒｓ）位摄影操作。对１２０例正常头颅ＣＴ图像进行测量，进行统计学处理，确定正常人岩锥长轴前延长线与头颅表面交点的大概位置。结果为：岩锥长轴前延长线交于对侧听眦线外眦后０．８２～２．９０ｃｍ区间，平均值左为１．６６ｃｍ，右为１．８２ｃｍ。结论，以平均值的邻值２ｃｍ为常数，即对侧听眦线外眦后２ｃｍ为岩锥长轴前延长线的前端体表定位标志，与其后端的乳突最突点共同确定岩锥长轴方向。     

胎骨移植治疗骨肿瘤缺损：附10例报告

近3年来，用制备的胎骨充填良性骨肿瘤及病样病变术后骨缺损，经观察10例效果良好。胎骨因其自身组织学和生理学特点，具有抗原性小、诱导成骨活性高，利于“爬行各代”等优点。而且来源丰富、采制简单、储存容易、费用低度，是一种良好的植骨材料，特别适于儿童及年老体弱患者自身取骨困难的骨缺损植骨需要。但其为异体骨，有一定免疫原性，抗支撑强度略差，应注意严格无菌操作、消除免疫原性、配合使用内、外固定等措施。     

复方18甲基炔诺酮透皮控释传递系统的LNG人体药物动力学与药效学评价

复方18甲基炔诺酮/雌二醇透皮控释传递系统(LNG/E_2 TCDS)能同时恒速释放低剂量的LNG和E_2,在1周内维持一个平稳而有效的LNG血药浓度。药动学与药效学研究证明,该系统释放的LNG能达到血清LNG目标水平,产生有效的排卵抑制(6/6)。LNG/E_2 TCDS可望发展成为一种安全、有效、非侵入性的新型生育调节避孕制剂。     

Antitumor activity of normal bone marrow cells

After separation of normal murine bone marrow cells in a Percoll density gradient cellular fractions with densities of 1.076 and 1.060 g/ml are capable of suppressing thein vitro growth of leukemia cells. The cytostatic activity of these fractions, however, does not surpass the level of antitumor antiproliferative activity intrinsic to intact bone marrow cells. These cells were found to be capable of joining the splenocytes, thymocytes, and lymph node cells in effector cytostatic cooperation and thus enhance the final antitumor effect. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 8, pp. 181–183, August, 1995     

Benign osteoblastoma of the parietal bone

A 5-year-old girl presented with a 1-year history of a subcutaneous swelling in the right parietal region. There were no cerebral symptoms or signs. Plain X-ray of the skull showed a lytic bony lesion with sclerotic margin. Computed tomography showed a hypodense, osteolytic lesion with thinned and bulged inner and outer skull tables with intact continuity. There was no intracranial lesion. At operation, the mass was found to be pink and granular, and was totally enucleated. Histology revealed it to be a benign osteoblastoma.