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31.
鲜王浆中超氧化物歧化酶的初步研究 总被引:1,自引:0,他引:1
本工作以一种非酶体系核黄素、四甲基乙二胺光照产生 Oi 氧化羟胺形成亚硝酸盐为原理测定 SOD 活性的新方法对新鲜蜂王浆中超氧化物歧化酶(SOD)的活性进行测定,结果表明,新鲜蜂王浆中存在 SOD,其活性含量大约为0.403ng/g。 相似文献
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袁德正 《内蒙古农业大学学报(自然科学版)》1990,(2)
矩阵∈AR~(n×n)称为实广义正定矩阵,如果对任意非零向量 X∈R~n,有XTAX>0成立。本文讨论了矩阵的kronecker积。Hadamard积和矩阵乘积的正定性,给出相应一些性质。 相似文献
34.
在论述计算机支持的协同工作定义的基础上,阐述了协同工作的模式和范围,介绍了子午线轮胎模具设计与制造的流程,及其汽车轮胎模具异地协同设计制造系统的关键技术. 相似文献
35.
The male sterility fluctuation of photo-thermo-sensitive genic ma1e sterile〔P(T) GMS〕lines induced by low air temperature is a key problem troubling the application of two-line system hybrid rice. The paper suggests to solve this problem by the breeding approeches, i.e, developing low sterile critical temperature P(T)GMS lines, herbicie resistant restorer lines, herbicide sensitive P(T)GMS lines and tetracycline-conditioned P(T)GMS lines to ensure the hybrid purity; and by the hybrid seed production techniques, i.e, taking the correct procedure of foundation seed production, the suitable district and season for hybrid seed production and the deep irrigation method against cold weather in high summer. 相似文献
36.
F. RODRÍGUEZ G. A. RAMÍREZ A. S. RAMÍREZ H. J. BALL A. ESPINOSA
DE LOS MONTEROS A. FERNNDEZ 《Zoonoses and public health》2002,49(5):226-229
Samples from the mammary tissue of 14 lactating goats (12 naturally infected and two experimentally infected) were examined for the presence of Mycoplasma agalactiae. A monoclonal antibody (5G12) was applied to formalin‐fixed, paraffin‐wax‐embedded sections and labelled by the avidin–biotin peroxidase complex (ABC) method. Histological examination of tissue sections revealed strong immunoreactivity in all animals included in the study. Mycoplasma agalactiae antigen was mainly detected in the cellular debris at the periphery of purulent exudates present within lactiferous sinuses, and lactiferous and interlobular ducts. In addition, M. agalactiae organisms appeared in the cytoplasm of the epithelium of ducts, and in infiltrating macrophages and neutrophils within the ducts, alveoli, interstitial tissue and regional lymph node sinuses. It is concluded that this monoclonal antibody‐based immunohistochemical technique is an efficient and specific method for the post‐mortem detection of M. agalactiae in cases of clinical mastitis as well as being a useful tool for the study of the route of infection and cellular types involved during mastitis caused by this organism. 相似文献
37.
获能是哺乳动物精子的成熟过程和受精的必要前提,获能液中添加物从不同方面影响精子获能;本文阐述了肝素、Ca2 载体A23187、葡萄糖、孕酮、咖啡因等添加物对精子体外获能的影响及其作用机制。 相似文献
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K. CARPENTER HELEN J. COTTRELL W. H. DE SILVA B. J. HEYWOOD W. G. LEEDS K. F. RIVETT MARGERY L. SOUNDY 《Weed Research》1964,4(3):175-195
Summary. The preparation of ioxynil, bromoxynil, and their salts is described, and information on solubilities and stability to storage is summarized. Although the toxicology of the herbicides is to be reported in greater detail, a preliminary statement is made here. Evidence of herbicidat activity under glasshouse conditions is indicated briefly, and supports the conclusion that both compounds are effective when applied to the foliage of a wide range of dicotyledon weed species. Seedlings of some weed species resistant to the phenoxy alkanoic acids are controlled under glasshouse conditions at doses as low as 0.125 lb/ac, and ioxynil has a wider range of activity than bromoxynil at these low doses. Graminaceous species tolerate 4–8 lb/ac of both herbicides without injury, and certain leguminous crops tolerate one or other herbicide at doses of 0.5–0.75 lb/ac. The contact action of the herbicides is rapid, there are also slower systemic effects, and seed germination is inhibited. In susceptible species the level of post-emergence activity is shown to be influenced by the growth stage of the weed, the distribution of herbicide on the foliage, and environmental factors of which light intensity appears to be most important.
Propriétés chimiques et biologiques de deux nouveaux herbicides: ioxynil et bromoxynil 相似文献
Propriétés chimiques et biologiques de deux nouveaux herbicides: ioxynil et bromoxynil 相似文献