华山松吸收光谱及叶绿素荧光特性的地理变异

利用分离的叶绿体作实验材料,发现华山松(Pinus armandi Franch.)南方种源的4阶导数吸收光谱在680nm处峰值较大,在670nm处峰值较小,而北方种源中出现了在680nm处峰值较在670nm峰值小的类群,推断北方种群反应中心活力有下降趋势。南、北种源之间的低温(77K)荧光发射光谱有明显差异,PSⅠ、PSⅡ发射峰位置出现地理变动。低温荧光激发光谱分析表明,地理变异主要发生在叶绿素a的分子状态上。研究还表明,完整的针叶因为有角质层、松脂等物质干扰,检测不出光谱的差异,不是理想的实验材料。     

水稻病毒的吸收光谱和荧光光谱

本文报导水稻簇矮病毒(RBSV),水稻矮缩病毒(RDV),水稻东格鲁病毒(RTV),水稻齿矮病毒(RRSV)和水稻草矮病毒(RGSV)等的吸收光谱和荧光光谱.结果表明:不同病毒有不同的吸收光谱带和荧光光谱带.它包括主峰,各次峰及其轮廓.通过不同相对强度的光谱,可以判断其浓度.这些光谱可以反映病毒的某些结构信息.同时通过光谱也可以鉴别水稻病毒的类型.     

THE STRUCTURE OF THE ULTRAVIOLET ABSORPTION SPECTRA OF CERTAIN PROTEINS AND AMINO ACIDS

1. The absorption spectra of a number of proteins in the region 2500 to 3000 A. have been found to comprise from six to nine narrow bands. In consequence of variation in the relative intensity of these bands from protein to protein, the absorption curve has a characteristic configuration for each protein. 2. These bands correspond closely in position with the narrow bands which appear in the absorption spectra of tryptophan, tyrosin, and phenylalanine. Tryptophan and tyrosin each present three bands, phenylalanine shows nine. 3. The bands in the proteins are accordingly attributed to these amino acids. In the proteins the bands are displaced from the positions which they occupy in the uncombined amino acids, in most instances, by 10 to 35 A. toward longer wavelengths. 4. The absorption spectrum of Pneumococcus Type I antibody resembles that of normal pseudoglobulin but shows characteristic differences.     

溶菌酶中水分子的红外吸收光谱

本文报导了不同水含量的溶菌酶中水的红外吸收光谱的测量结果.室温下,在远离纯水OH带及OD带的两侧分别出现高频与低频带,峰的位移大小随水含量的不同而改变.低温下,当R(克水/克蛋白)>0.2后,比值A./A.随水含量增大而增大.本文对室温下高频及低频峰的可能原因及与水的冻结过程的联系进行了讨论.     

振动光谱与蛋白质二级结构

红外光谱和拉曼光谱(统称分子振动光谱)应用于蛋白质构象研究经历了定性阶段和半定量阶段.近5年来,去卷积和二阶导教等提高分辨率方法以及曲线拟合方法的应用,使得振动光谱在定量计算蛋白质二级结构和监测蛋白质构象变化等方面取得突破性的进展,进入了定量化的阶段.     

鱼类消化道具有吸收外源生长激素的能力

采用草鱼生长激素夹心式酶联免疫吸附测定法（ＥＬＩＳＡ）,研究了重组鲤生长激素（ｒｃＧＨ）经胃或肠灌注后,胡子鲶、大口鲶和银鲫血清ＧＨ水平的变化规律。胡子鲶、大口鲶直肠分别灌注ｒｃＧＨ（１μｇ／ｇ和５μｇ／ｇ）后,血清ＧＨ水平迅速升高,而在对照组胡子鲶和大口鲶血清中未检测到内源性的ＧＨ,预示处理组血清ＧＨ水平的迅速升高是由ｒｃＧＨ从小肠内转移进血液引起的。胡子鲶胃内灌注ｒｃＧＨ（２５μｇ／ｇ）后,在     

THE CAROTENOIDS OF FOUR BLUE-GREEN ALGAE1

The carotenoids of 4 species of blue-green algae, Anabaena variabilis, Phormidium persicinum, P. ectocarpi, and P. fragile, were investigated. In each, ft-carotene was a major pigment and the only carotene detected. The xanthophylls present in Anabaena variabilis were echinenone, canthaxanthin, and myxo-xanthophyll. Each of the Phormidium species contained zeaxanthin as the major xanthophyll. In each, this was accompanied by trace amounts of echinenone and isocryptoxanthin. In addition, 2 new xanthophylls, spectrally resembling ^-carotene, were found in Phormidium persicinum and P. ectocarpi, while another, with a spectrum similar to that of myxoxanthophyll, was found in P. fragile.     

类胡萝卜素对亚油酸甲酯氧化的抑制作用

研究溶液中类胡萝卜素对2 ,2’ -偶氮二 (2 ,4短杠二甲基戊腈 ) (AMVN)引发的亚油酸甲酯氧化的抑制作用及色素的消耗变化。表明 β-胡萝卜素 ,叶黄素及胭脂树橙都按依赖于剂量的方式抑制亚油酸甲酯氢过氧化物的形成。41.7×10 -6mol/L的叶黄素及玉米黄质的抑制活性相近 ,高于β-胡萝卜素与胭脂树橙的活性 ,后两者活性近似。在83.3×10 -6mol/L浓度下鸡油菌黄质活性高于叶黄素 ,后者又高于 β-胡萝卜素与胭脂树橙 ,最后两者仍近似。结果表明下列五种类胡萝卜素对亚油酸甲酯氧化的抑制能力为 :鸡油菌黄质>玉米黄质≈叶黄素> β-胡萝卜素≈胭脂树橙。类胡萝卜素在抑制脂质氧化过程中 ,本身逐渐损失消耗 ,4h后在试验所用浓度下最高剩余量不超过20 %。其中鸡油菌黄质与胭脂树橙的消耗速度慢于 β-胡萝卜素与玉米黄质。