Ca^＋＋对链霉素抗原—抗体反应的抑制作用

为探讨临床中使用钙制剂抢救链霉素过敏休克病人有良好效果的原因,由被动血凝试验、被动皮肤过敏试验和ELISA法证实,Ca~( )可以抑制链霉素抗原-抗体的反应。这种抑制作用是通过Ca~( )链霉素抗原结合,封闭链霉素抗原决定簇来加以实现的。     

Social and psychological factors associated with adolescents'' self-acceptance of occlusal condition

Studies using plaster models of teeth and photographs simulating the full range of occlusal conditions have found high agreement between measures of adolescent social acceptability of these conditions and perceived need for orthodontic treatment. This study examined the association between adolescents' acceptability of their own occlusal condition, severity of malocclusion, and likelihood of undergoing orthodontic treatment. The factors predicting the acceptability of occlusal condition of 13-yr-olds, as assessed by the SASOC scale, were measurements of acceptability of general physical appearance, and the severity of occlusal condition. Variability in SASOC scores appeared to be independent of gender, socioeconomic status, and ethnicity. Gender, and severity of occlusal condition were important differences between subjects who had received, planned, or were undergoing orthodontic treatment, and those who had not. Neither SASOC scores nor perceived need for treatment accounted for a significant proportion of the variance between these groups. Although adolescents seeking orthodontic treatment had a greater severity of malocclusion than those not, little difference was observed between these groups in acceptance of occlusal condition.     

Prefrontal cerebral activity during a simple “rock, paper, scissors” task measured by the noninvasive near-infrared spectroscopy method

We conducted a noninvasive near-infrared spectroscopy (NIRS) study using the game of rock, paper, scissors (RPS) as a simple neurocognitive task for the prefrontal cortex (PFC) in 15 healthy volunteers. We employed an opposite “to lose” RPS task coupled with a normal “to win” RPS task, since the former requires inhibition of behavior, one of the most important functions of the prefrontal cortex. During the NIRS examination, subjects had to present one of the three RPS hands in response to hands displayed randomly on a computer screen every 1.5 s, and were required to show hands that lose to the computer, or that beat the computer. We measured the relative concentrations of oxyhemoglobin (oxy-Hb) using the prefrontal probes of the NIRS system during the tasks. The increases in oxy-Hb during the “to win” RPS task were small, but were quite large and laterally dominant during the “to lose” RPS task. The difference between the two tasks might have been due to the participants’ cognitive conflict with losing on the RPS. We conclude that losing is better than winning on the RPS as a sensitive indicator in the NIRS examination of PFC.     

胎肌条件培养液对白血病细胞的体外效应

以髓系(HL-60)与淋系(Molt-4)细胞为观察对象,用细胞计数、细胞集落培养、台酚蓝拒染及溴化二甲噻唑二苯四唑试验为观察手段,研究胎肌条件培养液(FMCM)对白血病细胞的影响.实验标本分为4组:①对照组.②20%FMCM处理组.③阿糖胞苷(Ara-C,1×10~(-7)M/L)处理组.④混合处理组(经FMCM与Ara-C二者的处理).发现:①FMCM对两个细胞株均无明显的直接作用.②当HL-60细胞经FMCM预处理或在用Ara-C处理同时加入FMCM,Ara-C对其抑制作用可为FMCM加强,已受Ara-C抑制的HL-60细胞则无此现象.③Ara-C对Molt-4的抑制作用不受FMCM的影响.由此而初步认为:①FMCM对白血病细胞似无明显直接作用.②某些(非全部)白血病细胞对Ara-C的敏感性可为FMCM加强.③在己受抑制的细胞中不呈现这种致敏现象.①提示FMCM有可能用于白血病临床治疗.     

胎肌条件培养液抗损伤效应的观察

胎肌条件培养液（ＦＭＣＭ）可在ＣＦＵ－ＧＭ体外培养中提供集落刺激活性。研究发现它还能在体外培养中保护ＣＦＵ－ＧＭ，减轻理化损伤因素对其生长的抑制效应。所用化学损伤因素为５×１０－７Ｍ的阿糖胞苷与９×１０－９Ｍ的三尖杉酯碱，物理损伤因素为放射（３．５Ｇｙ），热（４４℃，６０分钟）与冷（—２０℃，１６分钟）。在损伤因素作用下，ＣＦＵ－ＧＭ的集落产率受到明显抑制，用２０％ＦＭＣＭ处理后，抑制现象可以减轻。ＦＭＣＭ可以对抗多种因素对ＣＦＵ－ＧＭ的抑制作用，没有特异性。用胰蛋白酶或热（８５℃，３０分钟）处理后的ＦＭＣＭ不具上述保护效应，用酸（ＰＨ＝２），碱（ＰＨ＝１０），ＤＮＡ酶与透析处理则无明显影响。提示ＦＭＣＭ中起保护作用的活性物质可能为分子量大于１００００的蛋白质。     

B组轮状病毒WH-2株vp7基因的原核表达与抗体的制备

目的：在大肠杆菌中表达人B组轮状病毒WH-2株VP7蛋白并制备其兔抗血清。方法：根据B组轮状病毒（GBRV）WH-2株vp7基因的全序列设计引物,用PCR的方法扩增得到vp7基因的编码区。将其克隆到原核GST融合表达载体pGEX-KG内,转化大肠杆菌E.coliDH5α,IPTG诱导表达人B组轮状病毒WH-2株VP7蛋白,经SDS-PAGE分离纯化表达的蛋白免疫新西兰兔,制备人B组轮状病毒WH-2株VP7蛋白抗血清。结果：经鉴定确认,vp7基因以正确的方式插入到载体中,此重组表达载体经IPTG诱导后,可表达相对分子量为53.4 kDa的GST-VP7融合蛋白。制备的抗血清经同样诱导表达的表达载体pGEX-KG表达产物吸收后1：500倍稀释后用Western Blot分析,与53.4 kDa的GST-VP7融合蛋白获得特异性显色信号。结论：人B组轮状病毒WH-2株VP7蛋白成功在大肠杆菌中GST融合表达,所表达的蛋白和制备的抗体不但为研究结构与功能提供了物质基础,也为GBRV所引起的疾病预防、诊断和治疗等流行病学研究和临床诊断奠定了基础,具有重要实际应用价值。     

YAG激光器谐振腔光振状态的调整

本文介绍了调整谐振腔光振状态的方法和要点，它包括调整谐振腔体和其它的光学部件。本法可应用于YAG激光器谐振腔的维修拆卸重装工作中。     

金银花nrDNA ITS区聚合酶链反应条件的研究

目的:金银花nrDNA ITS区序列G C含量为68%,用常规的PCR方法扩增效果差.本研究通过改变扩增程序及使用改性剂的方法显著提高了金银花nrDNA ITS区的扩增效率.方法:分别从金银花叶及药材中提取总DNA,通过优化扩增条件,对nrDNA ITS区进行扩增,并比较了两种优化方法的差别及适应性.方法1:提高变性温度至97℃;方法2:添加混合改性剂(DMSO 4%-甘油10%).结果:与方法1相比,方法2可降低变性温度5 ℃,升高退火温度9 ℃,降低镁离子浓度至0.5 mmol/L,降低Taq DNA聚合酶用量至0.1 U(30 μl体系),PCR产物量显著提高,且可消除植物DNA粗提物中杂质的干扰.结论:通过提高退火温度及添加改性剂可克服高G C含量金银花nrDNA ITS区序列扩增的困难,该方法的建立有助于解决植物来源DNA模板的PCR扩增问题.     

相对湿度对空调环境至适温度影响的研究

本文研究空调室内相同温度（夏季：２４℃，２８℃：冬季：１９℃；２２℃）条件下相对湿度（分别为３０～７０％；８５～９５％）对至适温度的影响。以健康成年人为研究对象，以体温、皮温、皮温差、温热感和舒适感为观察指标。结果表明：空调室内气温相同时，皮温差、温热感、舒适感均随气湿不同而出现差异。夏季空调温度为２８℃、气湿为８５～９５％时，皮温差（２．１℃）已超出生理至适范围，温热感（１２．５％）和舒适感（０％）也随湿度增高而下降（Ｐ＜０．０１）。提出在制订空调至适温度卫生标准时，应考虑空气湿度对至适温度的影响。