Proximal load transfer with a stemless uncemented femoral implant

Bone stock preservation is crucial when performing total hip replacement in young patients. The aim is to save good bone stock for a possible revision procedure. Furthermore, there is an increasing demand from young and active patients to receive a new joint which allows a normal or nearly normal life style. With this in mind, we began, in 1993, to develop a new femoral implant. The purpose of this ultra-short stem was a physiologic strain distribution on the proximal femur with a proximal load transfer from the implant to the femoral bone. Main features were an almost complete absence of the diaphyseal portion of the stem, a well defined lateral flare with load transfer on the lateral column of the femur, and a very high femoral neck cut. These innovations resulted in a conservative implant on both the bone stock and the soft tissues. This implant, in the first years, was recommended only for young and active patients. Over the last thirteen years, this project has undergone several modifications but the basic principles of the implant have remained the same. In the present review, we present the rationale, the surgical technique and the clinical and experimental results so far obtained with this implant.     

胸腺内注射异基因抗原诱导鼠神经移植免疫耐受的实验研究

目的探讨小鼠胸腺内注射异基因抗原在同种异体异基因坐骨神经移植免疫耐受中的作用。方法自供体小鼠C57BL／6的脾细胞中提取MHC抗原注人受体鼠Balb／c小鼠胸腺内，于2周后移植供体鼠坐骨神经。48只Balb／c小鼠随机分为4组，A组（胸腺内注射组）、B组（自体神经移植组）、C组（冷冻异体神经移植组）、D组（异体神经移植加用免疫抑制剂组）。于3周后进行电生理学、组织学、免疫学检测。结果A组运动神经传导速度（38．23m／s）与D组（36．39m／s）相比无显著性差异（P〉0．05），组织学、电镜、免疫学（混合淋巴细胞培养及迟发性超敏反应）检测结果均证实B组分别优于A组、D组和C组。结论胸腺内注射异基因MHC抗原可诱导大鼠对异体坐骨神经移植的特异性免疫耐受。     

采用半透明效果实现医学三维整体可视化

目的通过改进直接体绘制技术（DVR）算法中的关键步骤，绘制能表达数据场中不同层次组织的内部结构。方法根据界面对光线的反射和物质本身对光线的衰减，将数据场划分为边界不丰富的简单数据场和边界丰富的复杂数据场，从而采用分段线性函数来构造阻光度传递函数（TF）；将数据场中低灰度体素点看为一种不发光但会导致采样光线衰减的物质；根据采样结束时采样光线的阻光度分布来调整TF，完成三维绘制。结果绘制出了不同层次组织的内部结构。结论本算法有效地解决了体素点相互遮挡的问题，实现了医学三维整体可视化。     

心理干预对行体外受精病人的影响

体外受精(IVF)治疗对不育夫妇既是一种生理负担又是一种心理负担,在IVF各个时期均表现出心理应激,其中胚胎移植后至妊娠试验前和IVF失败后应激最强,出现负性心理反应,以焦虑、抑郁多见。研究表明,通过心理干预能有效缓解患者的负性心理,并可能提高妊娠率和降低治疗中断率。     

Design of an intravenous oxygenator

The aim of this study was to design a new intravenous blood–gas exchange device and to estimate the design characteristics of the device with a dimensionless function by using a substance that can be used instead of bovine blood. In addition, the characteristics of oxygen transfer were estimated using empirical formulas and the reliability of the equations was ascertained by comparing their output with an experiment performed using bovine blood. The dimensionless function was derived using distilled water and bovine blood to estimate the oxygen transfer rate. Using the derived equations, the calculated oxygen transfer rates for bovine blood and distilled water were similar for Reynolds numbers ranging from 0.7 to 7.0. Therefore, it is possible to estimate the oxygen transfer rate in bovine blood, which is a non-Newtonian fluid, using distilled water, which is a Newtonian fluid. Moreover, it was possible to verify the related equations because the oxygen transfer rate could be estimated using the derived equations, according to the diameters of the various device modules.     

Derivation and spontaneous differentiation of human embryonic stem cells

Embryonic stem (ES) cells are unique cells derived from the inner cell mass of the mammalian blastocyst. These cells are immortal and pluripotent, retain their developmental potential after prolonged culture, and can be continuously cultured in an undifferentiated state. Many in vitro differentiation systems have been developed for mouse ES cells, including reproducible methods for mouse ES cell differentiation into haematopoietic and neural precursors, cardiomyocytes, insulin‐secreting cells, endothelial cells and various other cell types. The derivation of new human ES cell lines provides the opportunity to develop unique models for developmental research and for cell therapies. In this review we consider the derivation and spontaneous differentiation of human ES cells.     

MISE AU POINT D'UNE TECHNIQUE D'ADMINISTRATION IN VIVO DES VECTEURS GENETIQUES DANS LEMUSCLE CARDIAQUE

Objective In order to improve the in vivo gene transfer into the heart muscle, we have designed a ECG-synchronized microinjection system that allows sequential gene delivery to the myocardium.Methods A cannula was introduced into the right carotid artery of the Wistar rat under general anesthesia.With the ECG-synchronized injection during diastole, the genetic vector (Ad CMV lacZ ) infusion was performed with various concentrations( l07 ～ l010pfu ) and different frequency ( the ratio of heart beats per injection from 1: 1 to 4: 1 ). The hearts of the rats were removed after 7 days for histological examination. Results Best results were obtained with a total vector amount of l09 pfu and a good ratio 3: 1 between heart frequency and injection frequency. The transfection efficiency was increased by use of vasodilators and by an increase of vascular permeability. No signs of myocardial ischemia or ventricular arrythmia were observed. Conclusion We have established a novel and safe method for in vivo gene transfer into the heart. Transgene expression suggests that this method may be useful technique to study cardiac function of treat cardiac diseases by means of gene theratpy.     

白细胞介素-18基因修饰的胎肝细胞经脾移植对小鼠免疫功能的影响

目的：观察表达mIL-18的重组腺病毒基因修饰的胎肝细胞（AdmIL-18/BNL.CL2)经脾移植对正常小鼠免疫功能的影响。方法：实验组小鼠经脾移植AdmIL-18/BNL.CL2，同时设LacZ病毒对照组（Ad-LacZ/BNL.CL2),BNL.CL2细胞对照组及空白对照组。2周后处死，留取血清，制备腹腔巨噬细胞、脾淋巴细胞、肝组织匀浆液，提取肝组织总RNA。采用ELISA法检测各组小鼠血清、腹腔Mφ和脾细胞培养上清、肝匀浆中细胞因子的含量；采用半定量RT－PCR法，检测肝组织细胞因子mRNA相对表达量；以LDH释放法测定腹腔Mφ杀伤活性和脾NK细胞活性，用MTT还原比色法测定脾淋巴细胞的增殖活性。结果：实验组小鼠血清、细胞培养上清及肝匀浆中，IL－18、IL－2、IFN－γ、TNF-α稔均高于其它对照组，而IL－4、IL－10水平则低于对照组；半定量RT－PCR结果与ELISA检测结果一致；同时，实验组腹腔Mφ的杀伤活性和脾NK细胞活性，及脾淋巴细胞增殖活性也明显高于对照组。结论：AdmIL-18能有效转染至胎肝细胞并稳定表达mIL-18;AdmIL-18基因修饰的胎肝细胞经脾移植后，可显著提高肝脏、脾脏免疫细胞活性，活化腹腔Mφ，促进Th1类细胞因子表达，抑制Th2类细胞因子的分泌。