疏雄醇对板栗叶片、雄花和花粉的影响

研究了疏雄醇（ＳＸＣ）对板栗叶片、雄花和花粉的影响。结果表明：疏雄醇对叶片和雄花序的大小有明显的抑制生长作用，叶片鲜重有增加的趋势，而对花粉的萌发率与花粉管的长度无明显的影响。     

蚕豆细胞微核技术在遗传毒理学研究中的应用

回顾蚕豆细胞微核技术的建立和发展，综述国内研究概况，对该技术的可能发展趋势进行预测。     

Determination of copy number for 5S rDNA and centromeric sequence RCS2 in rice by Fiber-FISH

The copy number of 5S rDNA and centromeric sequence RCS2 was determined by extended DNA fiber based fluorescence in situ hybridization (Fiber-FISH) in rice (Oryza sativa ssp. indica cv. Guangluai No. 4) genome. In order to determine the copy number, it is necessary to know the basepair number that a given length DNA fiber contains under a microscope. Therefore, the length of two DNA fragments, in which the basepair number had been already known, was measured. The insert sequence of the tested BAC 38D17 was 136 kb and its extended DNA was 56.4 μm long, 2.41 kb/μm on average, while that of the tested BAC 44B4 was 144.5 kb in total and 55.7 μm long, 2.60 kb/μm on average under the microscope. They were very close to the theoretical value of B-DNA in the Watson-Crick DNA model, which is 2.97 kb/μm. According to the average value of basepair number per μm of the two samples mentioned above, that is, 2.51 kb/μm, it could be estimated that the copy number was about 686 for 5S rDNA and 286-1121 for the centromere sequence RCS2.     

家用洗洁精对蚕豆根尖的毒性效应

本文研究了８种家用洗洁精对蚕豆根尖的毒性效应，结果表明，在０．１％的浓度下，６种洗洁精溶液使得蚕豆根尖细胞的微核率显著上升，在１％和１０％的浓度下，８种洗洁精溶液均使得蚕豆根尖发黑，生长变形．     

温度、压力、底物浓度和光照强度对过氧化氢酶动力学性质的影响

本试验以极谱氧电极法测定苹果叶片中过氧化氢酶促反应曲线的斜率表示酶的活性,研究了温度、压力、底物浓度和光照强度等物理因子对过氧化氢酶活性的影响。结果表明,酶活性在10～50℃范围内随温度升高酶活性增强,底物浓度对酶的影响符合米氏方程;压力对酶活性的影响,随负压的加大,酶活性有提高的趋势;光强对酶活性的影响,表现为二次曲线型。     

Novel activity of KRAB domain that functions to reinforce nuclear localization of KRAB-containing zinc finger proteins by interacting with KAP1

Previously, we found that two isoforms of the ZNF268 gene (ZNF268a and ZNF268b2, with and without the KRAB domain, respectively) might play distinct roles in normal epithelia and in cervical cancer. Here we further investigated that KRAB domain defined the function disparity in part by reinforcing nuclear localization of ZNF268a. We found that the A-box of KRAB alone retained major specific nuclear localization activity. In contrast, the B-box alone did not have nuclear localization activity but enhanced it significantly. Consistent with the critical function of the A-box, each mutation of six conserved residues (V9, V11, F13, E16, E17 and W18) in the A-box dramatically impaired nuclear localization activity. Furthermore, the unique nuclear localization activity of KRAB was verified in seven additional KRAB-containing zinc finger proteins (KRAB-ZFPs), suggesting that it is a universal feature of KRAB-ZFPs. Finally, KRAB exerted its unique nuclear localization activity by interacting with the RBCC domain of its corepressor KAP1. Our results have revealed a novel mechanism by which the KRAB domain reinforces nuclear localization of KRAB-ZFPs by interacting with KAP1. Our study also suggests that loss of the KRAB domain in KRAB-ZFPs due to aberrant alternative splicing might contribute to carcinogenesis.     

Further molecular evidence for the Hordeum vulgare ssp. spontaneum in Tibet as ultimate progenitor of Chinese cultivated barley

106 aeeessions of Tibetan wild barley, including 50 accessions of the two-rowed wiht barley Hordeum vulgare ssp. sopntaneum （HS）, 27 accessions of the six-rowed bottle-shaped wild barley H. lagunculiforme （HL） and 29 accessions of the six-rowed wiht barley H. agriocrithon （HA） that separately represent different agrigeographical regions of Tibet, were used to study the genetic diversity and genetie differentiation using SSR markers selected from seven barley linkage groups. 229 allelic variants were identified with an average of 7.6 alleles/locus. The average of total number of alleles per locus in HA （6.4） is much higher than that in HS （3.9） and HL （3.4）. The genetie diversity and its standard deviation among the three subspecies were in the order of HS〉HL〉HA. Very significant genetic differentiation was observed among the three subspecies of wild barley. Comparisons of the results fiom this and previous studies showed a strong Oriental-Occidental differentiation of barley, and that Shannan region of Tibet might be the center of origin of the Tibetan two-rowed wild barley, thus supporting not only the hypothesis of a mono-phyletie origin of cultivated barley but also the proposition that the Tibetan two-rowed wild barley as ultimate progenitor of Chinese cultivated barley.     

泡沫镍上原位生长CoMn2O4多级空心纳米球作为超级电容器电极材料的电化学性能研究

采用水热法结合空气气氛中的热处理过程,在泡沫镍（NF）表面生长了锰酸钴（CoMn₂O₄）多级空心纳米球,通过X射线衍射仪（XRD）、场发射扫描电镜（FE-SEM）和X射线光电子能谱（XPS）等测试手段对纳米球进行了表征.在三电极电化学测量系统中,0.1Co²⁺-250电极材料在5 mA·cm^-2时的面积比电容高达6 184 mF·cm^-2.以0.1Co²⁺-250为正极,商用活性炭（AC）为负极组装而成的混合超级电容器,在1.6 mW·cm^-2时的最大能量密度为0.112 mWh·cm^-2.即使在功率密度为16 mW·cm^-2时,能量密度仍达到0.064 mWh·cm^-2.在2 mA·cm^-2的电流密度下,经过10 000次充放电循环后,电容保持了初始值的93%.因其优越的电化学性能和低成本的便捷合成方法,CoMn₂O₄多级空心纳米球作为电极材料具有重要的应用前景.     

植物激素对过氧化氢酶的影响

采用极谱氧电极测定过氧化氢酶酶促反应的双曲函数曲线,以回旧斜率的倒数表示酶的活性,研究不同浓度的生长素、赤霉素、细胞激动素、脱落酸和乙烯利对过氧化氢酶的影响,试验结果表明,生长素、赤霉素对过氧化氢酶有抑制作用,细胞激动素对过氧化氢酶有促进作用,脱落酸和乙烯利对过氧化氢酶无显著的影响。     

桑椹作为加工食品添加色素的研究

本文着重研究了桑椹的营养价值,色素的组成、含量和 PH、温度、紫外光对桑椹色素的影响。讨论了加工食品添加剂、防腐剂和加工工艺过程中 Fe~(+++)、Al~(++)的影响。认为桑椹是一种很有开发前途的天然植物色素资源,本文还对桑椹色素的提取、保存和利用作了初步的研究。