三种不同科属蛙类外周血细胞的比较

采用快速瑞氏-姬姆萨(Wright's-Giemsa's)染色法对斑腿泛树蛙(Polypedates megacephalus)和沼水蛙(Hylarana guentheri)的外周血细胞进行观察,并与北部湾棱皮树蛙(Theloderma corticale)己有的数据进行了比较.结果显示,三种蛙的血细胞均由红细胞、白...     

Production of Melanins by Ceruloplasmin

It was shown that ceruloplasmin, apart from the known oxidative conversion of dopamine into melanin, can also produce (DHI)-melanin from 5,6-dihydroxyindole and THP-melanin from tetrahydropapaveroline. Ceruloplasmin acts as an oxidase and the kinetic parameters for these oxidative reactions are reported. Since these ceruloplasmin-catalyzed reactions occur also at pH 7.4, they could have a significant physiological impact. This ceruloplasmin-oxidasic activity is enhanced by copper ions and inhibited by chelators, such as ethylenediaminetetraacetic acid (EDTA) and desferoxamine (DEF). Some possible implication of melanin production in blood are discussed.     

超高产杂交水稻皮秒分辨荧光特性

采用时间分辨荧光光谱测试系统，研究了超高产杂交水稻(Oryza sativa L.)两优培九(P9)和对照汕优63(SH 63)类囊体膜的荧光光谱特性和时间特性。以脉宽为120ps，重复率为4MHz，波长为514nm的Ar^-激光分别激发P9和SH 63水稻类囊体膜荧光。通过对其超快荧光的时间特性和光谱特性比较研究发现：无论是在灌浆期还是在扬花期，P9水稻类囊体膜中光系统I激发能传递的速度比光系统Ⅱ的快；P9和SH 63两种水稻类囊体膜在灌浆期的激发能传递速度都比扬花期的快；两种水稻类囊体膜的光谱特性还给出，在从扬花期到灌浆期这一生长发育过程中，SH63水稻类囊体膜的色素成分和结合状态发生了变化，而P9却没有出现这种变化。