中国种子植物区系定量化研究——Ⅰ区域性种子植物区系研究实用程序工作原理(QX—系列程序)

本文根据吴征镒教授对中国种子植物属分市区类型研究结果,研制出定量化研究区域性种子植物区系的电子计算机程序,应用本程序可完成某区系的分布区类型统计分析,科属组成分析和与其它地区以共有属关系构建的相似性系数的谁知盘中计算,同时可大量节省研究人员的劳动强度和时间,对提高研究水平有一定的效果。     

高产融合子Q4413的形态学与生理生化特征的研究

本文通过对枯草芽孢杆菌BR151衍生株与北京棒杆菌1134衍生株的赖氨酸高产融合子Q4413株的形态学、生理生化特性等方面的研究,揭示了融合子与双亲株在这些方面的差异,为Q4413株确系双亲株的重组子或新的融合子增加了佐证.     

壳聚糖固定化木瓜蛋白酶的研究

以壳聚糖为载体,成二醛为交联剂将木瓜蛋白酶固定化。5％戊二醛在4-6℃下处理载体5h,加酶液(3.5mg/mL蛋白,pH7.2)固定12h,活力回收达32％,作用于酪蛋白的半衰期为36天,其表观K_m(酪蛋白)值为0.075％(W/V),溶液酶的K_m值为0.086％;最适pH7.0～7.5,溶液酶为7.0～8.5。固定化酶在pH8.5以下,溶液酶在9.0以下活力稳定。固定化酶在45℃以下,溶液酶在75℃以下稳定。用6mol/L脲洗脱固定化酶4次(5.5h)活力仍有54.5％。用固定化酶处理啤酒浊度比对照下降了1.5-3.7倍,蛋白质含量下降了44％,冷藏(4℃)120天无冷混浊现象发生并保持了啤酒原有风味和理化性状。     

稀土元素Pr~(3+)、Nd~(3+)对蚕豆(Vicia feba)叶片原生质膜上Ca~(2+)·Mg~(2+)-ATPase活性的影响

本文介绍用二相分配法制备蚕豆叶片原生质膜上的Ca~(2+)·Mg~(2+)-ATPase,用以研究镧系,稀土离子对此酶活性的影响。初步证实Pr~(3+)、Nd~(3+)对依赖于CaM的以及不依赖于CaM的蚕豆叶片原生质膜上Ca~(2+)·Mg~(2+)-ATPase活性的抑制不是CaM专一的。     

肌钙蛋白C(Tropnin C)的提纯与鉴定

<正> 肌钙蛋白C(TnC)是肌钙蛋白复合体的钙结合亚基,系骨骼肌和心肌收缩系统的触发因子。研究表明TnC与钙调素(CaM)类似,具有EF手结构和四个特殊的钙结合区。TnC与Ca~(2+)、Mg~(2+)等金属离子的结合可发生构型变化及由此导致的体内一系列酶活性等生理功能的变化。提纯TnC是进行其诸方面研究的基础。     

人参多肽基因的酶法体外随机——定位诱变

本文报道了酶法体外随机——定位诱变人参多肽基因的原理和方法。该法把传统的随机诱变和现代的定位诱变融合起来,可灵活控制基因突变的随机性和定位性。我们用双脱氧末端终止法测定了三个突变株的结果证实了该法的合理性和可行性,     

1,25-双羟胆钙化醇及其受体含量检测的实验研究

 建立了一种改良的血清1,25-双羟胆钙化醇(1,25-Dihydroxycholecalciferol,DHCC)超微量放射受体检测(RRA)技术。完成了灵敏度、精密度、准确度、稳定性及特异性等技术指标。报告了我国健康青年血清DHCC正常值;检测了先天性佝偻病、青春期佝偻病病人及患肾性骨病奶牛等血清DHCC水平。 根据配体与受体相互结合的定量关系,建立了DHCCR(DHCC受体)检测技术。在游离与结合配基分离方面,除建立与比较了DCC(葡聚糖包埋的活性炭)及HAP(羟基磷灰石)方法外,还首次将IEF(等电聚焦电泳)应用于DHCCR分离技术。对佝偻病鸡小肠粘膜上皮细胞受体含量进行了检测并比较了鸡小肠、输卵管壳腺及肝组织DHCCR含量。     

人白血病细胞癌性促凝物(CP)的分离纯化及其特性的初步研究

用三步纯化法从人M_3型白血病细胞中分离纯化出人类肿瘤癌性促凝物(CP)。促凝活性回收率为24％,CP纯化倍数为2481倍。纯化CP在SDS-PAGE上为单一区带,其理化和酶学特性类似于动物肿瘤CP,分子量约为70 000,PI为4.8,在FVⅡ缺乏血浆中以及在含有组织因子(TF)抑制剂情况下仍能激活FX。CP促凝活性能被半胱氨酸蛋白酶抑制剂HgCl_2抑制,纯化CP能与抗动物肿瘤CP抗体形成免疫沉淀反应。     

Increasing carbon dioxide from five percent to ten percent improves rabbit blastocyst development from cultured zygotes.

One-cell rabbit zygotes were cultured at 39 degrees C in basal synthetic medium II (BSM-II) with 5%, 10%, or 15% CO2 and humidified air to determine the effect of CO2 concentration on development in vitro. After 4 days in culture, 37% of the embryos grown in 10% or 15% CO2 had reached the hatching blastocyst stage, but only 10% of the embryos were hatching when cultured under 5% CO2 (P = 0.01). Over all blastocysts, cell numbers were 207, 246, and 205 for the 5%, 10%, and 15% CO2 treatments, respectively. In a second experiment to determine if there was a beneficial effect, particularly at the blastocyst stage, of a higher concentration of CO2, embryos were cultured 4 days in either 5% or 10% CO2 or for 2 days in 5% CO2 followed by 2 days in 10% CO2. The numbers of blastomeres per embryo and embryo diameter were greater (P < 0.05) in embryos cultured continuously in 10% CO2 or in 10% CO2 only during days 3 and 4 of culture than in embryos cultured continuously in 5% CO2. In a third experiment, one-cell rabbit zygotes were cultured with 5% or 10% CO2 in a defined, protein-free medium consisting of 1:1 RPMI 1640 and Dulbecco's modified Eagle's medium. The proportion of embryos hatching and cell counts were significantly greater (P < 0.01) when cultured in the presence of 10% CO2. These data indicate that a 10% CO2 atmosphere exerts a beneficial effect on the development of zygotes into expanding and hatching rabbit blastocysts in vitro.     

Tyrosine phosphorylation of a common 57-kDa protein in growth factor-stimulated and -transformed cells.

Protein tyrosine phosphorylation was studied in macrophages and fibroblasts to identify putative components of post-receptor mitogenic pathways that might be functionally conserved in different cell types. Nondenaturing conditions were established for the approximately quantitative recovery of anti-phosphotyrosine antibody (alpha PY)-reactive proteins from cells. A common, 57-kDa alpha PY-reactive protein was identified by V8 protease peptide mapping in colony-stimulating factor-1 (CSF-1)- or granulocyte-macrophage colony-stimulating factor (GM-CSF)-stimulated BAC1.2F5 macrophages, in platelet-derived growth factor-stimulated NIH-3T3 cells, and in CSF-1-stimulated NIH-3T3 cells expressing the c-fms/CSF-1 receptor. The 57-kDa protein was phosphorylated on serine and tyrosine and was the only alpha PY-reactive protein band whose phosphorylation was reproducibly increased in GM-CSF-stimulated cells. The effect of the growth factors on the tyrosine phosphorylation of the 57-kDa protein could be mimicked by treatment of the cells with orthovanadate, a phosphotyrosine protein phosphatase inhibitor. In the absence of growth factors, tyrosine phosphorylation of the 57-kDa protein was higher in v-fms or c-fms (F969, S301)-transformed NIH-3T3 cells than in untransformed NIH-3T3 (c-fms) and NIH-3T3 (c-fms, F969) cells. These data indicate that the 57-kDa protein is a common target for growth factor-stimulated tyrosine phosphorylation and potentially important for growth factor mitogenic signaling.