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81.
Pea (Pisum sativum L.) chloroplastic phosphoriboisomerase (EC 5.3.1.6) can be purified to apparent homogeneity in less than 2 days time with a 53% yield. Important steps in the purification include heat treatment and pseudoaffinity chromatography on Red H-3BN Sepharose. The purified isomerase has a subunit molecular mass of 26.4 kD. The N-terminal sequence has been determined through 34 residues. pH optima are 7.8 (ribose-5-phosphate) and 7.7 (ribulose-5-phosphate); Km values are 0.9 millimolar (ribose-5-phosphate) and 0.6 millimolar (ribulose-5-phosphate). The enzyme is inhibited by erythrose-4-phosphate, sedoheptulosebisphosphate, glyceraldehyde-3-phosphate, and 3-phosphoglycerate at concentrations close to those found in photosynthesizing chloroplasts. Countercurrent phase partitioning experiments indicate that the pea chloroplastic phosphoriboisomerase interacts physically with phosphoribulokinase. 相似文献
82.
Renmei Ren Kanhui Yan Yanjie Su Hanjun Qi Bin Liang Wunyong Bao Frans B. M. de Waal 《Primates; journal of primatology》1991,32(3):321-327
Observations were made following 130 spontaneous aggressive incidents in two small breeding groups of captive golden monkeys
(Rhinopithecus roxellanae roxellanae). Participants were observed both during the first 10 min following these incidents and during matched control observations.
An increased contact rate was observed between opponents following the aggressive incident. Post-conflict contacts were characterized
by a number of behavior patterns: open mouth, rapid grooming, embrace, and crouching. Adult males played an important role
as mediator in agonistic disputes among females: males intervened in 93.6% of female fights. It is speculated that this intervention
behavior is related to the species' organization into one-male units. 相似文献
83.
Brefeldin A's effects on endosomes, lysosomes, and the TGN suggest a general mechanism for regulating organelle structure and membrane traffic. 总被引:81,自引:0,他引:81
Addition of brefeldin A (BFA) to most cells results in both the formation of extensive, uncoated membrane tubules through which Golgi components redistribute into the ER and the failure to transport molecules out of this mixed ER/Golgi system. In this study we provide evidence that suggests BFA's effects are not limited to the Golgi apparatus but are reiterated throughout the central vacuolar system. Addition of BFA to cells resulted in the tubulation of the endosomal system, the trans-Golgi network (TGN), and lysosomes. Tubule formation of these organelles was specific to BFA, shared near identical pharmacologic characteristics as Golgi tubules and resulted in targeted membrane fusion. Analogous to the mixing of the Golgi with the ER during BFA treatment, the TGN mixed with the recycling endosomal system. This mixed system remained functional with normal cycling between plasma membrane and endosomes, but traffic between endosomes and lysosomes was impaired. 相似文献
84.
Yang YB Lin CS Tseng CP Wang YJ Tsai YC 《Applied and environmental microbiology》1991,57(4):1259-1260
A d-aminoacylase from Alcaligenes faecalis DA1 has been purified to homogeneity by a simple purification procedure with two columns, Fractogel DEAE-650 and HW-50. The specific activity of the purified enzyme was found to be 580 U/mg of protein with N-acetyl-dl-methionine as the reaction substrate. The apparent molecular weight and isoelectric point of this enzyme were determined to be 55,000 and 5.4, respectively. 相似文献
85.
Yan Ming Ling Yihling Huang Shansheng Gong Shuqing Xu Zhenxing 《Biological trace element research》1991,29(3):281-288
Contents of Cu and Zn of into-pulmonary blood (IPB), out-pulmonary blood (OPB), Lung tissue, and supernatant and macrophages of Lung Lavage were determined in superior mesenteric artery occlusion (SMAO) shock of rabbits. Zn of pulmonary tissue was 11.42 +/- 0.60 and 14.52 +/- 1.78 (micrograms/g wet wt) in SMAO shock and control groups, respectively. Content of Zn was found to be lower, Cu was not changed, and Cu/Zn ratio increased in lung tissue in SMAO shock. Contents of Cu and Zn in other samples were not changed. The results suggest that lower Zn in lung tissue related to acute lung injury. 相似文献
86.
山西永济白草坪组具刺疑源类的发现及其地质意义 总被引:13,自引:0,他引:13
该文着重报道了山西永济白草坪组(一般认为系中元古界上部相当于蓟县系的层位),以具刺疑源类为主的微化石群,计有4类6属15种,其中包括1新属,4新种,1新组合,1亲近种,2未定种,新属是具细网状纹饰的复杂具刺疑源类Shuiyousphaeridium Yan gen.nov.,4新种是Shuiyousphaeridium membraniferum Yan sp.nov.,Dictyosphaera incrassate Yan sp.nov.,Foliomorpha stipuliferaYan sp.nov.,Manicosiphoninema shuiyouense Yan sp.nov.。本微化石群以球形疑源类为主体,以具刺疑源类的大量发育为特征,并伴生有推测是绿藻和褐藻的化石,其组合面貌与蓟县上前寒武系各组皆有明显区别,具有更高的进化程度,从生物地层标志推测白草坪组所在的汝阳群应归入震旦系。白草坪组具刺疑源类可能是横裂甲藻的原始分子,它在地层对比和藻类进化方面皆具有重要意义。 相似文献
87.
王国亮;南蓬;龚复俊;朱信强;袁晓;袁萍 《武汉植物学研究》1992,10(4):355-358
利用2DNMR结合其他波谱方法从苦皮藤种子油中鉴定了2个新倍半萜多元酯,它们分别是1α-苯甲酰氧-8β-烟酰氧-9α、11β-2乙酰氧-β-二氢沉香呋喃,1β-苯甲酰氧-2α、8β、9α、11β-4乙酰氧-β-二氢沉香呋喃,命名为苦皮藤酯2和3。 相似文献
88.
袁晓;卢大炎;王国亮;叶婉成 《武汉植物学研究》1992,10(4):359-362
从卫矛科南蛇藤属植物毛枝南蛇藤(Celastrus hookeri Prain)根皮中首次分离出一个红色立方体形结晶,经紫外、红外、高分辨质谱和~(13)C核磁共振谱分析,并与有关文献数据对照,确认是南蛇藤素。作者用薄层扫描和高效液相两种方法初步测定了毛枝南蛇藤根皮和根的木栓化表皮的南蛇藤素含量,结果表明南蛇藤素主要集中在根的木栓化表皮,含量在12%以上,而在整个根皮中的含量大约为1%。 相似文献
89.
活性氧对巨噬细胞呼吸爆发影响及云芝多糖的保护作用 总被引:2,自引:0,他引:2
用化学发光法观察到叔丁基氢过氧化物对培养的小鼠腹腔巨噬细胞呼吸爆发有强烈的抑制作用。云芝多糖经腹腔注射后,能增强巨噬细胞呼吸爆发功能对叔丁基氢过氧化物损伤的抵抗力。云芝多糖处理的巨噬细胞谷胱甘肽过氧化物酶基础活力显著提高,在叔丁基氢过氧化物作用下,云芝多糖处理的巨噬细胞仍有较高的谷胱甘肽过氧化物酶活力。说明巨噬细胞的免疫功能与谷胱甘肽过氧化物酶活力有关,非特异性免疫多糖可提高细胞抗氧化能力,减轻活性氧损伤作用。 相似文献
90.
人体和动物模型的体表物理信息地形图的研究 总被引:1,自引:0,他引:1
对人体头面、躯干、四肢、耳廓各局部几十个及整个人体等体表部位正、背面等210个部位进行超微弱冷光和温度测量,输入电子计算机,经特殊的自编程序处理,获得十分清晰的,由3000多数据构成的各个局部或人体整体的冷光和温度地形图。 对家兔左、右耳廓、胸腹部、背部都分别观察32个部位的冷光与体表温度,经计算机分析处理,每观察区域获得约由2000个数据构成的精确的冷光、温度地形分市图。并可见不同生理、病理状态及不同病程家兔体表冷光、温度等地形图呈有规律的改变。 此外,我们还编制了以体表左右相应对称部位差值为分析数据进行地形图分析的程序,用以人体和动物体表物理信息对称规律的研究。 本工作以图形的形式显示物理参量在体表的广泛的分布规律,以揭示机体内部的不同生理、病理状态。本方法定位准确、直观醒目,为研究体表信息及机体生命活动规律提供了与逐点直接测量方法相互补充的有益的新手段。 相似文献