Genetic resistance to aflatoxin in Japanese quail

Progress was rapid in attempts to develop lines of quail resistant to acute aflatoxicosis induced by oral dosing with aflatoxin. After five generations of selection, 8- and 11-fold differences were present in mortality between two selected lines and their respective control lines. These quail lines should be of value in investigating the physiological basis of resistance to aflatoxin.     

Avian pineal gland: progonadotropic response in the Japanese quail

Pinealectomy in juvenile Japanese quail (Coturnix coturnix japonica) exposed to stimulatory photoperiods results in delay of ovarian and oviducal development and decreased pituitary weight. These effects are transitory and occur during a phase of growth immediately preceding the onset of sexual maturity. No effect was found in males. These results suggest that the pineal gland in females has a stimulatory effect on gonadal growth during maturation.     

Photoperiodic control of the cloacal gland of the Japanese quail

Changes in photoperiod cause correlated changes in testes, cloacal glands, cloacal foam, and reproductive behavior of male Japanese quail. The cloacal protrusion may serve as a convenient external index of androgen, permitting repeated measurement without operation on or killing of the animal.     

Memory in the Japanese quail: effects of puromycin and acetoxycycloheximide

Intracerebral injections of puromycin produced memory deficits in naive quail trained to discriminate between red and green stimuli. Puromycin aminonucleoside, acetoxycycloheximide, and saline had no such effect. After a single reversal of the visual cues, naive quail treated with puromycin performed better than control birds. Also, puromycin had no effect on performance when injected into previously trained animals. High doses both of puromycin and acetoxycycloheximide inhibited ribonucleic acid and protein synthesis to a similar extent, while low doses of puromycin inhibited only protein synthesis. Since only puromycin inhibited memory, the basis for its effect appears more likely to be mediated by the action of peptidyl-puromycin rather than by the quantitative inhibition of macromolecular synthesis or by some nonspecific toxic action.     

Pineal function and oviposition in Japanese quail: superior cervical ganglionectomy and photoperiod

Bilateral ablation of the superior cervical ganglia appears to deprive the pineal body of sympathetic innervation. Although this procedure presumably interrupts the neural circuit for transmission of optic information to the pineal, oviposition rates of ganglionectomized females exposed to stimulatory (15-hour) or to nonstimulatory (4-hour) daily photoperiods do not differ from those of the controls.     

American children with reading problems can easily learn to read English represented by Chinese characters

With 2.5 to 5.5 hours of tutoring, eight second-grade inner-city school children with clear reading disability were taught to read English material written as 30 different Chinese characters. This accomplishment eliminates certain general interpretations of dyslexia, for example, as a visual-auditory memory deficit. The success of this program can be attributed to the novelty of the Chinese orthography and to the fact that Chinese characters map into speech at the level of words rather than of phonemes. It is proposed that much reading disability can be accounted for in terms of the highly abstract nature of the phoneme (the critical unit of speech in alphabetic systems) and that an intermediate unit, such as the syllable, might well be used to introduce reading.     

乳化植物甾醇对雄性日本鹌鹑生长性能及相关激素水平的影响

为研究乳化植物甾醇对雄性日本鹌鹑(Coturnix coturnix japonica)生产性能、胰岛素样生长因子1(IGF-1)和肾上腺皮质酮水平的影响,将100只体质量为(70±4)g的26日龄雄性日本鹌鹑分为4组,每组5个重复,每只鹌鹑每天灌喂含0、0.1、0.2和0.4 mg.mL-1植物甾醇的乳化液0.2 mL。21 d后,采食量、体质量增加和饲料转化率均无显著变化(P>0.05),但饲料转化率随植物甾醇灌喂量的提高呈下降趋势。植物甾醇乳化液均显著提高了鹌鹑血清中的IGF-1含量(P<0.05),但不影响皮质酮水平(P>0.05),血清丙二醛(MDA)含量也无显著变化(P>0.05)。0.04和0.08 mg.d-1植物甾醇显著降低了血清总胆固醇(TC)和低密度脂蛋白胆固醇(LDL-C)水平(P<0.05)。结果提示:植物甾醇能显著上调雄性日本鹌鹑IGF-1水平从而对其生产性能产生潜在影响。     

鹌鹑的遗传多样性研究

采用同工酶电泳技术 ,对陕西省大规模饲养的 2个蛋用品系鹌鹑群体的遗传多样性进行了分析。结果表明 ,两个群体中每个位点的等位基因平均数为 1.87,多态位点比率为 6 0 % ;引用国外同类研究结果 ,对国内外 2 1个鹌鹑群体用 7个多态位点的基因频率计算标准遗传距离并进行系统聚类 ,结果在 0 .12 5 2 6 7水平上 2 1个群体聚为 2类——野生群体和家养群体 ,家养群体中大体重鹌鹑与一般体重鹌鹑遗传距离较远 ;且 Mpi- IC,Mpi- ID和α- Gpd B基因为野生鹌鹑特有的基因 ,野生鹌鹑群体的基因多样度低于家养鹌鹑 ,在中性位点家养群体比现存同种野生群体保持着更高的基因杂合度。     

Age-related changes in quail meat

Chemical, amino acid, and mineral composition of the breast and legs was studied on quails aged 1, 30, and 60 days. By the end of the survey (60 days), the content of protein in their meat increased by 20.7%; the energy value was 20.15 higher; the concentration of histidine, arginine, leucine, and phenylalanine grew by 1.3–3.8 times; and the concentration of magnesium, iron, and copper increased by 0.08 g, 10.52 mg, and 12.83 mg, respectively.     

如何学习名词性从句

英语语法学习中,名词性从句的地位十分重要。虽然包含4 大从句,但讲清宾语从句 一种即可讲好其他从句,可从模块上讲解。     

从外语教学论多媒体语音室的发展方向

随着我国高等教育的快速发展,多媒体语音室在高校外语教学中发挥着越来越重要的作用,大大地提高了高等教育外语教学的效率和质量,尤其是在提高学生听力和会话能力方面具有不可替代的作用,也是从根本上摆脱老师讲学生听的“注入式”单向教学的重要手段。1多媒体语音室的发展历程多媒体语音室自上世纪七八十年代开始进入我国高校,最初也就是简单的语音教室,随着外语教学的发展和需求的进一步扩大,最初的语音教室也逐步地过渡到多媒体语音室。它正向着数字化方向发展,开发出了模拟半数字及全数字网络化的语言学习系统。传统的语音教室采用模拟…     

语音特征参数MFCC的提取及其应用

Mel频率是能够反映人耳对不同频率语音感知能力的一种频率表达方式.主要介绍了Mel频率倒谱系数( MFCC)的特点及提取方法,并提取了MFCC的一阶差分,使特征参数在说话人识别上能够更加准确的反映语音信息,提高识别率.     

如何学习计算机专业英语

计算机专业英语是计算机专业的一门必修课，学好计算机专业英语非常重要，不仅使学生掌握大量专业词汇，还能提高学生的阅读能力和写作能力。     

商水方言的语音与词汇特点

商水方言是中原官话的典型代表,是研究河南方言的重要部分。调查本地区语言实际,总结出该地区的语音与词汇特色,为河南方言研究的全面展开而努力。推求出该地区方言的音系,不仅为推广普通话提供便利,也为语音的历时研究提供基础;选择具有代表性的词条,为记录方言词汇与揭示悠久地域文化提供基础性支撑。     

智能电话语音系统在农业信息服务中的应用

为提高农业信息服务成效,近几年江苏省在20多个县农业部门建设了智能电话语音信息服务系统。广大农民通过电话拨号即能获得语音信息和专家咨询服务。该系统的运行为农业生产经营及时提供了技术和市场信息服务,取得了显著的经济和社会效益,也为解决农业信息服务"最后一公里"问题探索了路径。文章在信息资源建设、专家工作机制及制度的完善等方面,对进一步发挥系统信息服务的作用提出来了对策建议。     

“工学结合”教学模式之启悟

高等职业教育的主要任务是全面贯彻党的教育方针,以服务为宗旨,以就业为导向,走工学结合发展道路,为社会主义现代化建设培养千百万高素质技能型专门人才。高等职业技术教育以其独特的优势,体现其人才培养目标、教育方式、课程设计及教学必须满足社会服务、生产一线实际需要,注重知识与技能的应用能力培养的特点。