TAUTOMERISM AND SITE OF PROTONATION OF 1-METHYLCYTOSINE: PROOF BY NUCLEAR MAGNETIC RESONANCE SPIN-SPIN COUPLING     

MILES HT  BRADLEY RB  BECKER ED 《Science (New York, N.Y.)》1963,142(3599):1569-1571

New nuclear magnetic resonance data lead to a completely unambiguous proof that the predominant tautomeric form of 1-methylcytosine is the amino form and that in acid solution the molecule protonates at 3-N. The close similarity of the nuclear magnetic resonance spectra of this compound to the spectra of the cytosine nucleosides indicates that these structures also exist in the nucleosides. These conclusions are reached on the basis of the spectra of analogs labeled with N15 and of the proton spin decoupling measurements made at low temperature.  相似文献   

MALDI‐MS Lipid Profiles of Oocytes Recovered by Ovum Pickup from Bos indicus and 1/2 indicus × taurus with High vs Low Oocyte Yields     

KC Silva‐Santos  CR Ferreira  GMG Santos  MN Eberlin  LS Siloto  CO Rosa  TN Marcantonio  MM Seneda 《Reproduction in domestic animals》2014,49(5):711-718

The aim of the present study was to compare the lipid profile in oocytes of indicus and 1/2 indicus × taurus cows with high and low antral follicle count (AFC)/oocyte yields. After an OPU procedure (D0), antral follicles ≥3 mm were counted by ultrasonography (D4, 19, 34, 49, 64), and cows were assigned to groups with either high AFC (≥30 follicles; indicus, NH group; 1/2 indicus × taurus, AH group) or low AFC (≤15 antral follicles; indicus, NL group; 1/2 indicus × taurus, AL group). The lipid profiles of the oocytes were determined by MALDI‐MS. For GI, GII and GIII oocytes, the indicus samples tend to cluster separately from the 1/2 indicus × taurus samples. The lipid species [PC (P‐38:5) + H]⁺ and/or [PC (P‐36:2) + Na]⁺, [PC (38:2) + H]⁺, [PC (38:5) + Na]⁺ and [TAG (60:8) + NH⁴]⁺ were more abundant in indicus (NH and NL groups) than 1/2 indicus × taurus. The higher lipid content in the indicus oocytes likely reflects differences in the rate of lipid metabolism and may contribute to oocyte competence and embryo development.  相似文献   

A functional analysis of regional differences in the human fovea     

MILES WR 《Science (New York, N.Y.)》1948,108(2816):683

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NITRATE/NITRITE POISONING OF CATTLE ON RYEGRASS PASTURE     

T. J. NICHOLLS  E. J. MILES 《Australian veterinary journal》1980,56(2):95-96

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Use of a Custom Orthotic Boot for Management of Distal Extremity and Pad Wounds in Three Dogs     

Robert J. Hardie DVM  Diplomate ACVS & ECVS  James T. Lewallen CO 《Veterinary surgery : VS》2013,42(6):678-682

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虾蛋白肽对蛋鸡产蛋性能和蛋品质的影响     

朱碧英  汪依凡  池进军  吕子利 《家畜生态》2008,(6):22-25

研究和探讨了虾加工副产物的酶解产物（Enzymatic Hydrolysis Production,EHP）对蛋鸡产蛋率和蛋品质的影响。以虾加工副产物为原料,应用复合生物酶酶解技术制备EHP,选择产蛋率在80%以上的300日龄笼养褐壳蛋鸡288只,随机分成3组,在基础日粮中分别添加0、1.5g/100g、3g/100g虾加工副产物EHP,并替代相应重量的鱼粉,试验期为60天。EHP,可显著提高鸡蛋的哈夫单位（P〈0.05）,试验组蛋鸡产蛋率平均提高3.14%,料蛋比相应低于对照组。表明虾加工副产物EHP可显著提高产蛋高峰期过后处于衰减期的鸡蛋的哈夫单位及产蛋率。  相似文献   

甘蓝型油菜高含油量隐性胞核雄性不育两型系的选育   总被引：2，自引：0，他引：2  

李厚英  陈德珍  陈松  夏海乾  罗光智  余忠刚  苏跃 《中国油料作物学报》2003,25(4):122-124

采用复合回交方法,选育出甘蓝型油菜双低隐性核不育两型系。双低不育系121AB、123AB、175AB、932AB、933AB等表现高含油量、产量高等性状,品质优良。其中175AB、932AB、933AB含油量42．7％～44．0％,蛋白质含量24．2％～25．3％。组配的德油系列优质杂交油菜新组合在比较试验中均比对照种油研七号增产,增产率9．98％～27．34％,表现出较大的增产潜力。  相似文献   

高新技术在茶叶加工中的应用   总被引：1，自引：0，他引：1  

任俊银 《蚕桑茶叶通讯》1999,(3):2-5

本文简述了膜分离技术,超临界流体萃取技术,冷杀菌技术及真空冷冻干燥等新技术的基本原理及其在茶叶加工中的应用状况。  相似文献   

Rapid method for measurement of rate of adsorption of DDT by mud surfaces     

MILES JW  PEARCE GW 《Science (New York, N.Y.)》1957,126(3265):169-170

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利用¹⁰B示踪法研究栗钙土中硼肥的生物效应(简报)     

王沛芹  马兴旺  彭根元  黄庆文  林英钊 《中国农业大学学报》1992,(2):174-174

硼对植物营养生理的作用,不仅能使植物细胞壁坚韧与木质化,促进与增强植物的抗逆性(抗旱性与抗寒性),而且能促进植物根系发育及糖在体内的运输等。但是有关硼肥营养机理的研究报道较少,尤其是利用~(10)B 示踪研究植物硼肥营养及其在土壤中的转化,更是罕见。为此,我们应用~(10)B 研究了球茎甘蓝在栗钙土上对硼肥的吸收利用,为栗钙土的硼肥使  相似文献