人类转录因子样新基因TFL76的初步研究

运用基于基因组数据库特定基因同源基因的克隆策略得到人类新基因TFL76 ,它编码 12个C2 H2 型锌指基序 .其cDNA序列长 2 2 6 8bp,预测的编码蛋白含 6 77个氨基酸 ,分子量 (Mr)为 76× 10 3 .生物信息学分析表明 ,TFL76的N末端含有多种蛋白激酶的磷酸化位点和核定位信号 ,具有转录因子的特征 .染色体定位为 19q13.4 ,此位点存在很多与癌症相关的基因 .对 9.5d和 10 .5d的鼠胚进行全胚原位杂交 ,结果表明 ,此基因在前肢芽和后肢芽表达较高 .图 5表 1参 5     

The genetic architecture of pheromone production between populations distant from the hybrid zone of the pine engraver, <Emphasis Type="Italic">Ips pini</Emphasis>

Summary. Across North America, populations of the pine engraver, Ips pini, differ in their expressed ratios of the two enantiomers of ipsdienol, the main component of its aggregation pheromone. We confirm previous studies, showing that the percentage of (+)-ipsdienol ranged from approximately 40 to 70% for New York (NY) males and less then 5% for California (CA) males. We performed line crosses including the F1, F2, and backcross generations between these populations. These line crosses showed that most F1 hybrids produced an intermediate enantiomeric blend of ipsdienol that was closer to the CA blend, with a frequency distribution peak near 15% (+)-ipsdienol. There was also strong segregation to either parental type in the F2 and backcross generations, but not in a pattern that could be clearly described by a single autosomal locus. There was also an X-linked effect that caused some individuals in the F1 to have phenotypes more characteristic of NY populations. Generation means analysis confirms this X-linked effect, and also suggests a complicated autosomal dominance by dominance epistatic interaction. Despite the appearance of segregation, these results suggest a more complicated system of pheromone blend control than the single major gene previously found between divergent lines for high and low (+)-ipsdienol blends from the hybrid zone in British Columbia.      

几种土壤的基本理化性质与Cu2+吸附的关系

研究了大冶市几种类型土壤的基本性质及与Cu2+吸附的关系,结果表明,土壤对Cu2+的吸附量随其CEC值(记为CEC)而变化,供试土壤的Cu2+吸附量由大到小的顺序为石灰土→水稻土→潮土→棕红壤.加入铜浓度为5 mmol·L-1时11个土壤对铜的吸附量x((mol·g-1)与CEC的直线相关方程为x(Cu2+) = 2.018×CEC + 24.4 (r=0.7066).而影响CEC的因素,如Ph、粘粒含量及其组成、有机质、比表面等,也是决定Cu2+吸附量的重要因素.     

大鼠血红素加氧酶-1基因在乳酸乳球菌中的克隆与表达

采用RTPCR技术从大鼠脾总RNA中分离扩增HO1基因,将该基因克隆进pGEMTeasy质粒中,转化大肠杆菌DH5α,提取质粒,分析基因,酶切后与含有乳酸乳球菌启动子NisA的pSEC质粒连接,经电击转化,将重组质粒转入乳酸乳球菌NZ9000中,转化子在含有氯霉素的脑心浸液培养基上培养.用Nisin诱导HO1表达,SDSPAGE和Westernblot分析、鉴定表达产物,并且用分光光度法测定工程菌表达的HO1活性为0.45nmolmg(protein)-1h-1.图5参18     

植物铜素毒害及其抗性机制研究进展

Cu是植物生命活动必需的微量矿质元素，广泛参与各种生命活动；但过量Cu胁迫将诱导植物细胞产生大量活性氧，引起膜脂过氧化，膜透性增大，细胞内容物大量外渗，甚至发生细胞死亡。Cu^2 扩散到细胞核内会诱发DNA之间、蛋白质之间以及DNA和蛋白质之间发生分子内和分子间交联，DNA链的断裂、重排和脱嘌呤作用等前诱变损伤以及DNA期外合成、DNA甲基化异常等遗传毒害。植物细胞在长期进化过程中形成了各种抗Cu素毒害机制，如细胞壁的固着作用、质膜的限制作用、有机小分子(有机酸、植物螯合肽、金属硫蛋白)螯合作用等。文章综述了有关研究的最新进展。     

Indoor and outdoor household dust contamination in Cincinnati, Ohio, USA

Despite some progress in reducing the average lead level in the USA, the streets of Cincinnati, Ohio, are still contaminated by heavy metals. High levels of heavy metals will have significant unequivocal ecological impacts and pose a potential health hazard. This study evaluates the level of heavy- metal contamination in household dust and examines its relationships with the external environment. Samples of outdoor and indoor dust were collected from middle-income residential homes in the Greater Cincinnati Metropolitan District and the metal content was analysed by inductively coupled plasma atomic emission spectrophotometry. Results showed that the mean levels of lead in outdoor and indoor dusts are 650 g g-1 and 377 g g-1 and the copper levels are 253 g g-1 and 510 g g-1, respectively. The median levels are 156 g g-1 and 139 g g-1 for outdoor and indoor lead dusts and 35 g g-1 and 124 g g-1 for outdoor and indoor copper dusts. The degree of contamination may be ascribable to the age of the dwelling unit and the neighbourhood, the time when the unit was last painted, the presence of pets and the type of space heating. In addition, car exhausts seems to be a possible source of contamination.     

BVR多芯铜导线过电流故障下燃烧及火焰传播研究*

为深入研究BVR多芯铜导线过电流故障下燃烧及火焰传播特征,采用堆栈技术分析导线受热形变,并利用高速摄像机记录故障导线发热、熔断及绝缘燃烧现象,研究导线发热形变、熔断时间及燃烧时火焰传播速度与电流值变化关系。结果表明:当I=136 A时,导线不发生熔断,只有当高温线芯直接接触周围可燃物才可引发火灾;当I=153 A时,导线会发生熔断现象,且熔断时间随过电流值升高而缩短;当I=204 A时,导线发生熔断,断路电弧引燃周围热解气体,火焰前沿迅速蔓延至导线两端,平均火焰前沿传播速度达2.2 m/s,平均明火持续时间达8.2 s,整根导线无需外界可燃物即可发生明火燃烧。研究结果可为起火原因认定提供技术指导。     

我国铜资源物质流分析研究

铜是我国应用最为广泛的有色金属,研究铜资源利用和循环状态对我国经济可持续发展具有重要的战略意义。论文从铜的生产、加工制造、使用和废铜处理4个阶段详细阐述了铜循环的"STAF"物质流分析模型,并以此模型分析了2004年我国铜的流动状况和社会存量变化,得出结论: 1998~2004年,我国铜工业的P_Z、P_S、M_Z和M_S平均值分别为49.08%、25.98%、57.14%和21.45%,远低于欧洲发达国家水平。对比1994年与2004年我国铜物质流图可知,10年来我国铜循环的各阶段中所有流入量和流出量都有较大提高,废铜再资源化程度虽有提高,但较之快速增长的铜需求量仍显不足。因此在资源危机面前,加强政策引导与科研力度,大力提高一次铜的资源生产率和二次铜的再资源化效率是我国铜工业可持续发展的工作重点。     

电镀污泥中铜和镍的湿法冶金回收技术研究进展

电镀污泥中含有多种高品位的金属元素,以铜和镍的湿法回收利用为重点,综述了国内外电镀污泥中重金属元素铜、镍的资源化综合利用的研究进展。     

城市饮用水源地水质健康风险评价

介绍饮用水水源受到基因毒物质和躯体毒物质所致的健康危害的风险度计算模型,并应用于西安市饮用水源地饮水途径健康风险评价,分别计算出了各类污染物的风险度。结果表明：（1）基因毒物质镉所致健康风险大约为10^-7a^-1,躯体毒物质所致风险在10^-12～10^-10之间。所以,基因毒物质是首先控制的污染物质。（2）对于躯体毒物质,铅的风险度是最高的,躯体毒物质所致的风险度大小排序为Pb〉NH3-N〉Hg〉挥发酚。（3）饮用水中的所有有害物质的健康危害总风险度未超过国际辐射防护委员会（ICRP）推荐的最大可接受限值5.0×10^-5a^-1,也没超过瑞典环保局、荷兰建设和环境部推荐的最大可接受水平6.0×10^-5a^-1。研究结果可直接确定该市地表水源水质的风险污染物的主次及治理的优先顺序,为该市地表水源水质风险管理提供了帮助。