应用合成肽研究柯萨奇B病毒衣壳蛋白VP1的共同抗原表位

对柯萨奇B4病毒(CVB4)衣壳蛋白VPl保守区的亲水性和二级结构进行分析和预测,选择可能代表优势抗原表位的肽段进行合成(VPl-l肽,RIYF KPKHVK AYV),并截取了该肽段的前12个残基(VPI-2肽)用同样方法进行合成.用VP1-1肽免疫家兔制备出高效价抗体,应用酶联免疫吸附法(ELISA)检测,这些抗体与CVBI-6病毒均有结合反应,VP1-1肽与型特异性CVB1-6抗体均有良好的结合反应,表明VP1-1肽是CVB的共同抗原表位.用VP1-1肽检测心肌炎患者血清CVBIgM抗体,阳性率在40%左右.     

Activation of CD8+ T cells by allogeneic class II-deficient B-cell lines derived from patients with bare lymphocyte syndrome

The major histocompatibility complex (MHC) class II antigens (Ags) are known to carry the major stimulating determinants of the primary mixed lymphocyte reactions (MLR). We investigated the mechanism of generating HLA class I-directed alloreactive T-cells in primary MLR. With the use of class II-deficient EBV-transformed B-lymphoblastoid cell lines (B-LCLs) derived from patients with bare lymphocyte syndrome (BLS), we have demonstrated in the present study that class I disparity alone can trigger primary MLR in the absence of exogenous IL-2. The CD8+ T cells were primary MLR-responsive cells, and the CD4+ T cells seem to play no role in primary MLR when class II alloantigens are not involved in stimulation. Addition of autologous macrophages did not influence the primary MLR response. The primary MLR was completely blocked by anti-class I or anti-CD8 antibodies but not by anti-class II or anti-CD4 antibodies. The MLC-generated CD8+ T cells exhibited cytolytic activity as well as proliferative responses. The proliferative response of the CD8+ T cells was specifically directed against class I antigens, demonstrated by proliferative assays; and the helper-independent CD8+ T cells were generated only when the activation of CD4+ T cells did not occur. This observation suggests that functional recruitment of T-cell receptor (TCR) repertoire is under active regulation, and the suppression of CD8+ T-cell helper recruitment appears to be dictated by the CD4+ T-cell subset. Further analysis of the primed T-cell specificities showed that alloreactivity of the CD8+ T cells was mostly accounted for by the HLA-B Ags.(ABSTRACT TRUNCATED AT 250 WORDS)     

Laparoscopy-assisted urologic surgery through minilaparotomy

Minimally invasive surgery has gained wide acceptance as a method of reducing postoperative pain and curtailing the convalescence period. We have devised a modified surgical technique of laparoscopy-assisted surgery through minilaparotomy. It is a hybridized form of conventional open and laparoscopic surgery and it combines the benefits of both techniques by reducing postoperative pain and scarring as in laparoscopy, but at the same time maintaining the safety of conventional open surgery. From January 1992 to September 1999, we performed laparoscopy-assisted surgery through minilaparotomy in 167 patients. The operative time for laparoscopy-assisted surgery through minilaparotomy ranged from 79 to 290 minutes (mean 125). There was no conversion to open surgery, no peri- or postoperative complications, and only 3 patients needed a blood transfusion at any stage. Pain was significant on the first day but resolved quickly. All patients resumed consistent oral intake on the second day. All patients commenced ambulation by the second postoperative day and were able to resume full ambulatory activity by the fourth postoperative day. The final would size did not exceed 10 cm in size and all patients expressed satisfaction with their wounds. In conclusion, we believe that laparoscopy-assisted minilaparotomy surgery is a truly minimally invasive technique maintaining the advantages of conventional surgery. Our method could become a first-line approach for simple nephrectomy, living donor nephrectomy and radical nephrectomy, as well as surgery for kidney and ureter stones.     

慢性肾功能不全患者血清及尿液超氧化物歧化酶含量的变化

用放射免疫分析测定７５例肾病患者血清和尿液含铜锌离子超氧化物歧化酶（Ｃｕ－Ｚｎ－Ｓｕｐｅｒｏｘｉｄｅｄｉｓｍｕｔａｓｅ，简称Ｃｕ－Ｚｎ－ＳＯＤ或ＳＯＤ－１）的含量，并与５１名健康人对比。结果显示，慢性肾功能不全（ＣＲＦ）血透组患者血清ＳＯＤ－１含量显著增高（Ｐ＜０．０１），随着血液透析期的延长，其含量有渐升趋势；非血透组略有降低（Ｐ＞０．０５；其它肾病组明显降低（Ｐ＜０．０１）。三组患者尿液ＳＯＤ－１含量呈不同程度增高（Ｐ均＜０．０１），并随着病变的严重程度而增幅更明显，血／尿ＳＯＤ－１比值也随之降低。本文初步分析了这些变化的原因及意义。     

Preparation of poly(amide-imide)s by means of triphenyl phosphite, 1. Aliphatic-aromatic poly(amide-imide)s based on trimellitimide

Aliphatic-aromatic poly(amide-imide)s with high molecular weight (η_inh up to 2,91 dl/g in DMAc/5% LiCl) were synthesized by direct polycondensation reaction of imide-containing dicarboxylic acids and aromatic diamines using triphenyl phosphite in N-methyl-2-pyrrolidone (NMP)/pyridine solution in the presence of metal salts. The factors affecting the reaction of N-(trimellitoyl)glycine and 4,4′-oxydianiline were investigated. The molecular weight of the polymer varied with the amount of metal salts, showing a maximum at a concentration of about 1 wt.-% CaCl₂ or about 2 wt.-% LiCl in the reaction mixture. A monomer concentration of about 0,2 mol/l gave the most favorable result. Among the solvents tested, NMP was most effective. Similarly, polycondensations of several combinations of three imide-diacids with various aromatic diamines were carried out. Solubility, thermal properties, and tensile properties of the polymers are discussed.     

Preparation of graded porous titanium coatings on titanium implant materials by plasma spraying

Graded porous titanium coatings have been deposited on titanium substrates for dental implants by plasma spraying in an argon atmosphere. X-ray diffraction (XRD), scanning electron microscopy (SEM), surface roughness measurement, and tensile strength tests were performed on graded porous coatings. The results showed that Ti(3)O(5) was formed in the outermost surface of the porous coatings due to oxidation. The graded porous coatings consisted of three layers. The outer layer was full of macropores with a surface roughness of approximately 100 microm. The diameter of many macropores reached and even surpassed 150 microm, which could be beneficial for tissue to grow into the coating. The middle layer consisted of a mixture of micropores and macropores. The inner layer was a very dense and tight interface layer that included mechanical, physical, and metallurgical bonding. In tensile strength tests, testing bars peeled off the coatings, because the adhesive agent fractured, but the coatings remained intact.     

Characterization of acrylic bone cement using dynamic mechanical analysis

Dynamic mechanical analysis (DMA) was used to characterize the properties of acrylic bone cement with the addition of tricalcium phosphate (TCP), hydroxyethyl methacrylate (HEMA), and ethylene glycol dimethacrylate (EGDMA). The glass transition temperature of acrylic bone cement is >100 degrees C; the cement has a flat modulus response near human body temperature. The height of the damping peak decreases and becomes broader with increasing TCP content. Thus, TCP is incompatibile with acrylic bone cement. When the frequency is changed from high to low, the damping peak shifts to low temperature. The shift in damping peak with frequency indicates that this relaxation is time-dependent. When acrylic bone cement contains TCP with HEMA and EGDMA, the incompatibility between acrylic bone cement and TCP can be ameliorated.     

Windows环境下步进电机匀加速的实现与计算机程序设计

本文主要介绍了奔腾计算机和步进电机的接口电路,提出了步进电机匀加速的控制算法,探讨了在 Windows 环境下以 Visual C++实现步进电机匀加速的实现途径和多任务环境下匀加速程序的设计方法。     

鄂伦春族Y染色体短串联重复序列多态性研究

目的 调查鄂伦春族Y染色体上10个短串联重复序列基因座及单倍型的遗传多态性。方法 应用PCR和变性聚丙烯酰胺凝胶电泳结合银染显色分型技术，检测102名无关系鄂伦春族男性血样。结果 在DYS392、DYS438、DYS439、DYS456、DYS459、DYS460、DYS461、DYS462、DYS389Ⅰ、DYS389Ⅱ等10个基因座中共检出44个等位基因，等位基因频率分布在0．418（DYS461）至0．727（DYS389Ⅰ）之间，除了DYS461（0．418）和DYS462（0．479）以外，其余等位基因频率均大于0．5。由10个基因座组成的Y染色体单倍型系统单倍型有101种，单倍型频率0．99。结论 上述10个Y-短串联重复基因座在鄂伦春族群体中具有较好的多态性，单倍型具有很高的遗传多态性。