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91.
1-Aminocyclopropane-l-carboxylate (ACC) synthase from applefruits was purified over 5,000-fold by conventional column chromatography.By immunizing mice with this partially purified enzyme preparation,8 hybridoma lines producing monoclonal antibodies against appleACC synthase were isolated. While all 8 clones immunoprecipitatednative ACC synthase, only two clones recognized the putative(48 kDa) ACC synthase on Western blots. When a partially purifiedACC synthase preparation was incubated with S-adenosyl-L-[carboxyl-14C]methionine(AdoMet), only one radioactive protein of 48 kDa was detectedon sodium dodecyl sulfate-poly-acrylamide gel electrophoresis.This radioactive protein was specifically immunoprecipitatedby the monoclonal antibodies, indicating that apple ACC synthaseis specifically radiolabeled by its substrate AdoMet, as istomato ACC synthase. Thus, the monoclonal antibodies recognizedboth native and AdoMet-inactivated forms of ACC synthase. Whilethese antibodies failed to im-munoprecipitate ACC synthase isolatedfrom ripe tomato fruits, ripe avocado fruits or auxin-treatedmungbean hypocotyls, they were effective in immunoprecipitatingthe enzyme isolated from ripe pear fruits. (Received August 11, 1990; Accepted October 17, 1990) 相似文献
92.
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
93.
C T Liu Z M Guo 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1991,197(4):400-403
To study biochemical changes in cerebrospinal fluid (CSF), we developed a reliable technique for repeated collection of CSF in anesthetized strain 13 guinea pigs. The animal's head was mounted in a stereotaxic instrument with ventral tilt at 30 degrees, and cisternal puncture was made with an L-shaped, 23-gauge needle through the shaved skin. Clear CSF was collected in a 1-ml syringe surrounded by crushed ice. Each collection procedure lasted for 3 min, and three consecutive collections produced about 0.2 ml of CSF. Sampling was repeated at 3-hr intervals. With intravenous saline infusion (10 ml/kg.hr), a total volume of 0.6-1.0 ml of CSF was collected over 6 to 12 hr. Animals maintained a mean blood pressure, heart rate, and minute volume, with few changes during CSF sampling for the entire collection. 相似文献
94.
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
95.
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
96.
羊草草原枯枝落叶分解的研究——主要优势植物的分解速率和损失率 总被引:15,自引:2,他引:13
分解速率和损失率从不同侧面反映了枯枝落叶分解动态,羊草草原主要优势植物,羊草(Leymus chinensis),拂子茅(Calamagrostis epigejos),减蓬(Suaeda glauca),碱茅(Puccinellia tenuiflora),五脉山黎豆(Lathyrus quinqueneruivs),碱蒿(Artemisia anethifolia)分解速率的季节变化动态近似倒“V”字型,损失率的季节变化呈S型,反了枯枝落叶的失重情况,枯枝落叶的化学组成成分是造成不同种植物间分解差异的主要原因,特别是C/N比与分解快慢有密切关系,分解初期,枯枝落叶的损失符合指数衰减模型,枯枝落叶损失95%所需时间,羊草群落约为8.8a,杂类草群落约为9.7a,碱茅群落约为7.1a,碱蓬群落约为4.7a。 相似文献
97.
9种针阔叶幼树的蒸腾速率、叶水势与环境因子关系的研究 总被引:24,自引:2,他引:22
应用QK-1气孔仪和压力室测定了樟子松、青杨等9种针阔叶幼树的蒸腾速率与其叶水势及与环境因子的关系。采用多元线性回归和逐步回归对观测值的统计分析结果表明:在土壤供水良好的条件下,其蒸腾速率主要受气象因子的影响,与其叶水势的相关性不显著。控水试验结果表明:在水分胁迫条件下其蒸腾速率与其叶水势和土壤含水量的相关性最显著。 相似文献
98.
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
99.
100.