加碘芝麻油中碘含量测定方法的研究

本研究根据加碘芝麻油颜色深，碘含量低这一特点，通过对样品进行碱灰化处理，采用离子选择电极法对碘含量进行测定。其变异系数为2.8%(n=5)，加标回收率在92.0%～100.6%之间，能够很好地满足实际测定的需要。     

Alpha-芋螺毒素TxID合成方法的优化

在常规两步氧化法合成的基础上,对芋螺毒素TxID第2对二硫键形成的条件进行了优化。优化条件包括有无氮气保护、氧化试剂中碘的浓度、三氟乙酸(TFA)含量、氧化时间等多个参数,研究其对TxID氧化折叠的影响。结果表明,氮气保护有利于TxID的氧化折叠,碘浓度需5~10倍于巯基浓度,TFA含量对氧化折叠影响不明显,氧化时间约5 min为宜。     

烟叶烘烤特性研究——I．烟叶自由水和束缚水含量与品种及烟叶着生部位和成熟度的关系

为弄清烤烟品种K326和翠碧1号的烘烤特性，根据渗透原理，用阿贝折射仪测定经蔗糖溶液浸泡的2个品种不同部位、不同成熟度烟叶组织前后的浓度，换算出烟叶自由水和束缚水含量。结果表明：翠碧1号自由水含量显著低于K326，束缚水含量则显著高于K326；烟叶着生部位自下而上，总水分含量和自由水含量渐次降低，而束缚水含量渐次升高；烟叶成熟度自欠熟至过熟，总水分含量、自由水、束缚水含量均渐次降低。     

旱稻叶片含氮量与水分含量的定量关系

在池栽条件下研究了不同水分处理对早稻叶片氮素含量以及叶片组织水势、自由水和束缚水含量的影响。结果表明：在不同土壤水分条件下，植株全氮含量基本上表现为先下降而后升高再下降的变化趋势，随土壤含水量增加叶片中全氮含量逐渐减少，叶片的组织水势和自由水含量逐渐增大，束缚水含量逐渐下降。叶片氮素含量与分蘖高峰期（播种后40～46d）的组织水势呈显著负相关。叶片氮素含量（y）与叶片组织水势（z）间存在y=-0．6999x＋2．3764的显著直线回归定量关系。     

基因专利法律保护相关问题研究

通过对基因的可专利性问题的探讨,阐明了科学发现和科学发明的区别,并结合我国现有专利法对基因专利的法律保护及基因的生物学特点,剖析了基因专利的新颖性、创造性和实用性要求,同时论述了基因专利的保护范围.     

Differences in chlorophyll fluorescence parameters and water content in heteromorphic leaves of <Emphasis Type="Italic">Populus euphratica</Emphasis> from Inner Mongolia,China

We studied three typical heteromorphic leaves of Populus euphratica trees growing in the Wuhai region of Inner Mongolia,China,i.e.,lanceolate,broad-ovate and dentate broad-ovate leaves and mainly focused on the changes in chlorophyll fluorescence parameters and free water and bound water content.The results show that the values of Fm(maximal fluorescence yield),Fv/Fm(maximum photochemical quantum yield of PSII) and Fv/F0(potential quantum efficiency of PSII) of lanceolate leaves were the least on young trees,while these parameters were the least on the ovate leaves of old trees.Compared with young trees,the free water content of heteromorphic leaves of old trees increased significantly,i.e.,by 78.94% in lanceolate leaves and in the leaves of broad-ovate and dentate broad-ovate by 10.99% and 10.60%,respectively.Correlation analysis showed that free water content is significantly related to Fv/Fm and Fv/F0 in young trees,while the relationship of total water content with Fv/Fm and Fv/F0 is positive in old trees.     

Iodine biofortification in tomato

Iodine is an essential element in the human diet, and iodine deficiency is a significant health problem. No attempts to increase iodine content in plant‐derived food (biofortification) have so far been particularly effective. We studied iodine uptake in tomato (Solanum lycopersicum L.) to evaluate whether it is possible to increase the iodine concentration in its fruits. Iodine translocation and storage inside tomato tissues were studied using radioactive iodine. Potassium iodide was also supplied at different concentrations to tomato plants to evaluate the resulting iodide concentration both in the vegetative tissues and the fruits. The results indicate that iodine was taken up better when supplied to the roots using hydroponically grown plants. However, a considerable amount of iodine was also stored after leaf treatment, suggesting that iodine transport through phloem also occurred. We found that tomato plants can tolerate high levels of iodine, stored both in the vegetative tissues and fruits at concentrations that are more than sufficient for the human diet. We conclude that tomato is an excellent crop for iodine‐biofortification programs.     

Comparison of three preoperative skin preparation techniques in ponies

The purpose of this study was to evaluate the efficacy of 3 preoperative skin preparations (povidone‐iodine [PI] removed with 70% isopropanol, and 4% chlorhexidine gluconate [CG] removed with either 70% isopropanol [CA] or sterile saline solution [CS]) in ponies. Eighteen ponies were randomly assigned to one of the 3 preoperative skin preparation groups. The skin of ponies was aseptically prepared with PI removed with alcohol, or 4% CG removed with either alcohol or sterile saline solution. The antimicrobial efficacy of each skin preparation technique was assessed quantitatively by culturing for surface bacteria with replicating organism detection and counting plates. The percentage of negative cultures, the percentage of cultures with >5 colony forming units (CFU) and the percentage bacterial reduction after the cleansing scrub, the sterile scrub, and the surgical procedures were compared. There was a significant difference between CG and PI in percentage bacterial reduction after the cleansing scrub, but no significant difference at any other time (sterile scrub, post operative skin sampling). In a comparison of the number of negative microbial cultures at each sampling point, there were no significant differences among the 3 skin preparation techniques. There were no significant differences among the treatment groups comparing the number of cultures with a high colony count (>5 CFU) after the cleansing scrub. Skin preparation with CS and PI resulted in significantly fewer cultures with >5 CFU after the sterile scrub than CA. Post operatively, CA had a higher number of samples with >5 CFU than CS and PI. PI removed with alcohol and 4% CS are equally effective in the reduction of skin bacteria after a sterile skin scrub in the operating room; however, CG was more effective in reducing bacterial numbers after the cleansing scrub. The number of cultures with high bacterial counts was greater post operatively, when alcohol was used as a rinse with chlorhexidine. In cases where a sterile scrub is not performed following a cleansing scrub, CG may be a better choice than PI. CA should not be used as a presurgical skin preparation method in ponies.     

两种药物对两个翘嘴鲌群体的急性毒性试验

为研究南北水系翘嘴鲌群体对活性碘和阿维菌素这2种常用水产药物的耐受性差异,为翘嘴鲌在养殖过程中进行消毒和杀虫工作提供数据参考和理论支持,开展了2种药物对南北水系2个翘嘴鲌选育群体鱼种的急性毒性试验.试验中,每个群体对每种药物均设置3个平行,每个平行设对照组和5个浓度梯度试验组.试验结果显示,活性碘对南方水系和北方水系翘...