The neuroprotective effect of L-Theanine and its inhibition on nicotine dependence

The benefits of tea for human health are widely accepted all over the world. L-Theanine, a nonprotein amino acid found in tea plants, is the major tea component that contributes to the unique pleasing taste of tea. L-Theanine has been shown to promote relaxation, enhance cognitive performance and act antagonistically against the excitement induced by caffeine. Recently, it was found that L-Theanine had inhibitory effect on nicotine dependence. This paper reviews the neuroprotective properties of L-Theanine and discusses the inhibitory effects of L-Theanine on nicotine dependence.     

X射线荧光光谱法用于不锈钢建材元素分析的方法研究

应用分子克隆技术,构建重组腺病毒质粒Adtrack-canstatin(Ad-can),并建立人卵巢上皮性癌移植瘤动物模型.动物模型建立后,将荷瘤裸鼠随机分为3组,Ad-Can、Ad-GFP和PBS对照组,每组6只.治疗采用肿瘤内局部多点注射4.0×1010PFU/ml病毒上清液或PBS液0.1 ml,共2次,注射间隔72小时.8天后肿瘤体积出现明显差异,Ad-can组明显小于对照组,P<0.01,而Ad-GFP和PBS对照组间无明显差异,P>0.05.另外,Ad-can组CD105明显减少,微血管密度降低,P<0.05.结果提示:Canstatin基因能明显抑制人卵巢上皮性癌的生长,其机制可能是通过抑制肿瘤新生血管形成起作用的.     

重复性经颅磁刺激对吗啡依赖小鼠条件性位置偏爱表达的影响

通过检测重复性经颅磁刺激（rTMS）对吗啡依赖小鼠条件性位置偏爱（CPP）表达的影响,探讨rTMS对吗啡依赖小鼠的治疗效应。30只雄性ICR小鼠随机分为对照组、CPP模型组和rTMS治疗组。CPP模型组与rTMS治疗组通过交替注射吗啡和生理盐水建立CPP模型;对照组皮下注射等量生理盐水替代吗啡。在成功建立CPP模型的基础上,rTMS治疗组采用频率为1Hz的低频脉冲磁场进行治疗,每天治疗15min,连续7d;CPP模型组进行假电磁刺激操作;对照组不作任何处理。在rTMS治疗后分别检测三组小鼠的CPP表达并进行比较。结果显示在rTMS治疗的前3d内,rTMS治疗组小鼠的CPP值显著低于CPP模型组（P < 0.01）,且维持在相对稳定的范围内。结果表明1Hz rTMS能有效抑制吗啡依赖小鼠的CPP表达,可能成为戒毒治疗的新方法。     

5种灵芝硒多糖抑制小鼠S180肉瘤生长作用的比较研究

比较5种灵芝硒多糖S180肉瘤的抑制作用及其与抗氧化作用的关系.用浓度为2.5g/L的SeGLP5种系列产品的溶液对BALB-c小鼠进行皮下注射,以正常小鼠作阳性对照,以注射生理盐水的荷瘤小鼠作阴性对照,连续注射14d,第15天测定小鼠血液和肝脏中SOD的活性和MDA的含量,并测肿瘤重量.结果显示,5种灵芝硒多糖对小鼠S180肉瘤都有不同程度的抑制作用,抑瘤率从62.79%到32.26%不等,其中SeGLP-1B的抑瘤作用最显著(P0.001),SeGLP-2B次之,其余各种多糖的抑瘤效果也都显著或极其显著(P0.005或P0.001).认为SeGLP5种系列产品均可通过提高机体的抗氧化能力来抑制S180肉瘤的生长,其抑瘤效果与硒的含量呈正相关的剂量依赖关系.     

Maternal inhibition of hepatitis B surface antigen gene expression in transgenic mice correlates with de novo methylation

Differential modifications of the genome during gametogenesis result in a functional difference between the paternal and maternal genomes at the moment of fertilization. A possible cause of this imprinting is the methylation of DNA. The insertion of foreign DNA into transgenic mice allows the tagging of regions that are differentially methylated during gametogenesis. We describe here a transgenic mouse strain in which the expression of the hepatitis B surface antigen gene is irreversibly repressed following its passage through the female germ line. This inhibition is accompanied by the methylation of all the HpaII and HhaI sites within the foreign gene, which we have shown to be integrated into a site on chromosome 13. The irreversibility reported here contrasts with what is found with other transgenic mice sequences which are reversibly methylated after passage through the male or female germ line, though in both cases methylation appears to be important in the imprinting process.     

对-二氯苯在乙醇中的溶解度测定

测定了对一二氯苯在乙醇中的溶解基准曲线和溶解度曲线，分别获得了-二氯苯的浓度与峰高、浓度与温度关系图。     

含水乙醇汽油稳定性研究

使用市售车用93号乙醇汽油和纯汽油分别配制出高乙醇含量和高含水量的含水乙醇汽油,试验研究乙醇汽油中乙醇含量、含水量以及5种添加剂(正丁醇、异丁醇、甲基叔丁基醚、棕榈酸、失水山梨醇单油酸酯)对含水乙醇汽油相分离温度的影响。结果表明,含水量减少、乙醇含量增加都可降低含水乙醇汽油的相分离温度;使用纯汽油配制的含水乙醇汽油含水量在3%时,相分离温度低于-20℃,且在大气环境温度为-5~10℃的条件下放置30d以上不发生分层现象;使用乙醇汽油配制的含水乙醇汽油比使用纯汽油配制的含水乙醇汽油稳定性要强,在相同乙醇含量和含水量下,前者的相分离温度要低9~15℃;5种添加剂均能明显降低含水乙醇汽油的相分离温度,其中正丁醇和异丁醇的效果最好。     

非晶聚合物构型熵的温度关系

基于无序非晶材料“关联蕈排区域”的构型熵理论，运用构型熵与热容龟差的关系式、弛豫时间与活化势垒的基本公式，及聚合物量热学的实验结果和热容量差与温度的基本关系，研究了4种情况下构型熵、介电弛豫指数和关联重排区域大小的温度变化关系，研究结沦表明：聚合物的构型熵随温度的上升均增大，并由同一物质非品态的热容量与晶态的热容量之差决定，其变化限制在热容量差为恒定及与温度成倒数的范围之内。     

Thickness dependence of magnetic properties in DyFeCo films

Films of amorphous DyFeCo were deposited on glass substrates using RF sputtering deposition system. The thickness dependence of the coercivity of DyFeCo films prepared under the same sputtering conditions was investigated.It is found that the composition is nearly thickness independent, while the coercivity is shown to increase with the film thickness increasing at the beginning, then above a certain thickness decrease with the thickness increasing. The thickness dependence of the coercivity is believed to be due to microstructure-induced variations in the short-range order during the film growth.     

Parametric dependence of the line emissions in sonoluminescence

Based on a series of spectral measurements of sonoluminescence, this paper investigates parametric dependence of the line emissions in single bubble sonoluminescence (SBSL) and multi-bubble sonoluminescence (MBSL). The experiments show that the intensities of the OH* radical line, the sodium line and the noble gas lines in SBSL are relevant to the driving pressure of the acoustic field and the concentration of the noble gases dissolved in host liquids. The intensity of line emissions in total spectrum increases with the decreasing driving pressure and the increasing concentration of noble gases. Parametric dependence of line emissions in MBSL consists with that in SBSL. Line emissions in sonoluminescence should correspond to lower temperature inside the bubbles. SBSL and MBSL share the same spectral structure, and the difference between them found by previous experiments should result from the different temperatures inside bubbles.     

分光光度法测定乙醛催化剂中的钯含量

拟定了乙醛催化剂中钯的分析方法。用４－（２－吡啶偶氮）－间苯二酚作显色剂，在ｐＨ＝５．６０－９．００范围内与钯形成红色本合物，其最大吸收峰位于５０２ｎｍ处，表观魔鬼洋吸光系数为２．５２×１０＾４Ｌ．ｍｏｌ＾－１．ｃｍ＾－１。钯浓度在０－２．４μｇ／ｍＬ范围内等符合比尔定律。     

溶剂法分离制备大豆肌醇磷脂

利用乙醇为溶剂对大豆磷脂中肌醇磷脂进行分离。建立了乙醇一正己烷体系分离肌醇磷脂的分离度的概念。研究了可以用不同浓度的乙醇对大豆磷脂中的肌醇磷脂进行分离。得出当乙醇浓度为55％时,乙醇一正己烷体系有一个较佳的分离度。