毛细管水解及反相高效液相色谱分析蛋白质的氨基酸组成

 毛细管水解及反相高效液相色谱分析蛋白质的氨基酸组成陈平,梁宋平（湖南师范大学生物研究所,长沙４１０００６）氨基酸组成的分析是阐明蛋白质和多肽化学特性的基础,在蛋白质与多肽的氨基酸组成分析中,常采用对水解管反复充氮并抽真空的方法使蛋白质和多肽在隔绝氧气...     

链霉菌酪氨酸酶基因的克隆与表达

本文综述了近年来对链霉菌酪氨酸酶基因的研究。由酪氨酸酶合成黑色素是链霉菌属各个种的共同特性,并受到酪氨酸酶基因的控制。链霉菌几个种的酪氨酸酶基因已克隆到,其产黑色素的特性使之作为重要的标记基因得以广泛应用,同时,该基因在链霉菌的不同种及不同属的微生物中得到了高水平的表达。链霉菌酪氨酸酶基因表达调控的分子机制也得到较深入的研究。     

Inheritance of resistance to watermelon mosaic virus in the cucumber line TMG-1: tissue-specific expression and relationship to zucchini yellow mosaic virus resistance

The inbred cucumber (Cucumis sativus L.) line TMG-1 is resistant to three potyviruses:zucchini yellow mosaic virus (ZYMV), watermelon mosaic virus (WMV), and the watermelon strain of papaya ringspot virus (PRSV-W). The genetics of resistance to WMV and the relationship of WMV resistance to ZYMV resistance were examined. TMG-1 was crossed with WI-2757, a susceptible inbred line. F₁, F₂ and backcross progeny populations were screened for resistance to WMV and/or ZYMV. Two independently assorting factors conferred resistance to WMV. One resistance was conferred by a single recessive gene from TMG-1 (wmv-2). The second resistance was conferred by an epistatic interaction between a second recessive gene from TMG-1 (wmv-3) and either a dominant gene from WI-2757 (Wmv-4) or a third recessive gene from TMG-1 (wmv-4) located 20–30 cM from wmv-3. The two resistances exhibited tissue-specific expression. Resistance conferred by wmv-2 was expressed in the cotyledons and throughout the plant. Resistance conferred by wmv-3 + Wmv-4 (or wmv-4) was expressed only in true leaves. The gene conferring resistance to ZYMV appeared to be the same as, or tightly linked to one of the WMV resistance genes, wmv-3.     

龙血树真菌群及其对血竭形成的影响

从柬埔寨龙血树（Ｄｒａｃａｅｎａｃｏｃｈｉｎｃｈｉｎｅｎｓｉｓ）茎杆中分离到３０３株真菌,其中镰刀菌属（Ｆｕｓａｒｉｕｍ）菌株占总分离频率的５２％,其次是短梗霉（Ａｕｒｅｏｂａｓｉｄｉｕｍ）和枝孢霉（Ｃｌａｄｏｓｐｏｒｉｕｍ）。通过活体接种对血竭产生的影响试验表明,对血竭形成起重要作用的真菌主要是禾谷镰刀菌龙血树变种（Ｆ．ｇｒａｍｉｎｕｍｖａｒ．ｄｒａｃａｅｎａ）等４株红色镰刀菌,可使血竭形成量提高６６％－１２０％。     

人Ⅳ型胶原的提纯及其抗血清制备

采用胃蛋白酶限制性消化,NaCl分级盐析,还原和烷基化反应,纤维素离子交换层析从人胎盘组织分离纯化Ⅳ型胶原.经SDS-PAGE电泳鉴定符合Ⅳ型胶原α肽链电泳带.用纯化的Ⅳ型胶原免疫兔制备出高效价的特异抗血清.     

神经生长因子结构与功能研究进展

神经生长因子(NGF)是神经营养因子家族的典型代表, 它控制着脊椎动物周围和中枢神经系统中部分神经元的发育和存活.NGF的三维结构是以“胱氨酸结”和β折叠为基础,它以二聚体的形式结合细胞表面的受体从而发生生物学效应.参与这些反应的氨基酸残基已通过化学修饰和定点突变法加以确定,这有助于更进一步理解其结构与功能的关系.     

生物分子相互作用分析技术应用实例（四）——实时监测分子生物学过程

利用BIA技术来观察DNA之间的任何相互反应.包括：DNA的延长、连接和退火等.无需任何标记并可测定相互作用的动态参数.     

Respiratory function of velopharyngeal constrictor muscles during wakefulness in normal adults

Launois, Sandrine H., Judy Tsui, and J. Woodrow Weiss.Respiratory function of velopharyngeal constrictor muscles during wakefulness in normal adults. J. Appl.Physiol. 82(2): 584-591, 1997.The levator velipalatini (LVP) and the superior pharyngeal constrictor (SPC) influencevelopharyngeal patency and soft palate position, but their behaviorduring respiration is incompletely characterized. To further clarifytheir respiratory function, we recorded electromyographic activity(EMG) in the LVP and the SPC in awake normal subjects breathing orally.EMG data were obtained in six subjects for the LVP and in nine subjectsfor the SPC. EMG activity and timing and ventilation were measuredduring isocapnic hypoxia and hyperoxic hypercapnia. Phasic EMG activitywas inconsistently present during unstimulated oral breathing. Timingof EMG phasic activity was variable for both muscles. Peak LVP activitywas mainly or exclusively expiratory in three of six subjects. Peak SPCactivity was mainly or exclusively expiratory in five of nine subjects.With chemostimulation, recruitment of phasic activity was observed inthe LVP in four of six subjects and in the SPC in five of ninesubjects. Tonic activity increased in four of six subjects for the LVPand in three of nine subjects for the SPC. However, the response wasalinear, and intersubject as well as breath-to-breath variability wassubstantial. In conclusion, LVP and SPC are characterized by the highinter- and intrasubject variability of EMG activity, timing ofactivation, and response to chemostimulation.