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1.
动物细胞遗传学研究现状及其应用 总被引:1,自引:0,他引:1
本文介绍了细胞遗传学在动物方面的研究现状及其在畜牧业上的应用。细胞遗传学的研究主要以染色体为对象。目前世界上现存的哺乳动物约4100多种,其中进行过染色体研究或核型分析的有1468种,我国已研究过的有242种。细胞遗传学在人类医学上的应用是众所周知的,在畜牧业上主要用于对种畜进行细胞学检查,以消除对家畜繁殖性能有影响的畸变染色本,以染色体标记来识别家畜品种,对环境污染的监测及遗传操作中的染色体工程。 相似文献
2.
刺槐无性系种子园老龄母树截干矮化试验 总被引:2,自引:1,他引:1
利用刺槐萌蘖力强的特性,对刺槐无性系种子园老龄化后的树体进行截干试验,促使其萌蘖形成新的树冠,并进行整形修剪,结果表明:老龄母树截干矮化,效果良好,达到预期目标。解决了原母树树体高大釆种困难的问题,为提高刺槐种子园老龄化后种子产量和质量进行了有益的探索。 相似文献
3.
Physiological Response of Multiple Contrasting Rice (Oryza sativa L.) Cultivars to Suboptimal Temperatures
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M. M. Rachoski A. Vidal O. A. Ruiz A. B. Menéndez A. A. Rodríguez 《Journal of Agronomy and Crop Science》2015,201(2):117-127
The physiological response of multiple rice cultivars, eighteen initially and eight cultivars later on, to suboptimal temperatures (ST) conditions was investigated in laboratory and outdoor experimental conditions. Treatment with ST decreased growth in different extents according to the cultivar and affected the PSII performance, determined by chlorophyll fluorescence fast‐transient test, and stomatal conductance, regardless the experimental condition. Two groups of cultivars could be distinguished on the base of their growth and physiological parameters. The group of cultivars presenting higher growths displayed optimal JIP values, and higher instantaneous water use efficiency (WUEi), due to a lower Gs under ST, unlike cultivars showing lower growth values, which presented worse JIP values and could not adjust their Gs and hence their WUEi. In this work, we detected at least two cultivars with superior tolerance to ST than the cold tolerant referent Koshihikari. These cultivars could be used as parents or tolerance donors in breeding for new crop varieties. On other hand, positive and significant correlations between data obtained from laboratory and outdoor experiments suggest that laboratory measurements of most of the above mentioned parameters would be useful to predict the response of rice cultivars to ST outdoor. 相似文献
4.
由于太阳辐射方向的时刻改变和太阳辐射能的不稳定性,导致碟式太阳能发电系统利用率始终较低。为了解决这个问题,本文提出了一种基于PLC控制的全天候自动跟踪方式,利用光照强度与光照强度阈值的差值作为跟踪方式切换的判据,不仅消除了程序跟踪造成的累积误差,而且避免了光电传感器在阴天或多云时无法工作的问题。为保证系统在任何天气情况下均可稳定运行,信息反馈元件增加了风速传感器、温度传感器及倾角传感器。另外,在设计系统硬软件时,采取了一系列措施来进一步降低系统运行成本。 相似文献
5.
Graziotti G Ríos C Rodríguez Menéndez J Victorica CL 《Anatomia, histologia, embryologia》2000,29(5):273-276
The objective of this study was to describe the arterial distribution of the hindfoot of the llama (Lama glama). Ten adult llamas, preserved in 6% formalin solution at 0 degree C, were dissected. The arterial system was perfused with a solution of 14% coloured plaster; the venous system was perfused with a solution of 17% coloured industrial gelatin. Angiographies were also obtained. In the llama, the arterial distribution is of the saphenous type and this simple sort of irrigation could be used as a didactic model. The caudal branch of the saphenous artery divides into the small lateral plantar artery and the larger medial plantar artery, which continues as the plantar common digital artery III, and it is the main blood supply of the hindfoot. The dorsal pedal artery is underdeveloped and the perforating tarsal artery does not exist in this species. The plantar common digital artery III divides into the plantar proper digital II, III and IV. Branches from the plantar proper digital artery III supply the digits. We compared the arterial distribution of the hindfoot of the llama with that of other domestic animals including the one-humped camel (Camelus dromedarius). 相似文献
6.
Menşure Özgüven Bilge Şener Ilkay Orhan Nazım Şekeroğlu Muzaffer Kirpik Murat Kartal Ipek Peşin Zülküf Kaya 《Industrial Crops and Products》2008,27(1):60-64
Artemisia annua L. is an aromatic-antibacterial herb that destroys malarial parasites, lowers fevers and checks bleeding, and of which the secondary compound of interest is artemisinin. The objective of the present study was to determine yield, yield components and artemisinin content of A. annua L. grown under four nitrogen applications (0, 40, 80 and 120 kg ha−1) in the Çukurova region of Turkey in 2004 and 2005. Field trials were conducted at Çukurova University, Agricultural Faculty Field Crops Department. In the study, plant height, number of branches, fresh herbage yield, dry herbage yield, fresh leaf yield, dry leaf yield, essential oil content and artemisinin content (by high performance liquid chromatography, HPLC) were examined. By analysis of variance, nitrogen doses had no any statistical effect on the traits investigated except for artemisinin content. Artemisinin content of the dried leaves were significantly affected by nitrogen applications, which varied from 6.32 to 27.50 mg 100 g−1. Contents were from 120 and 80 kg ha−1 nitrogen for the years of 2004 and 2005, respectively. 相似文献
7.
This study focuses on the determination of structure change of surface area, morphology, crystallinity and pyrolysis characteristics of cellulosic feedstock treated by hot acid solution. The microscopic structure change of acid-treated samples was examined by using BET, SEM/EDX, XRD and pyrolysis–GC–MS under reasonable condition. Results showed that both surface area and pore volume of treated sample were conspicuous increased partial due to dissolution of silica and organic polar-components. Morphological change of plant cell wall surface was viewed as damage such as exfoliation, cave and fracture appeared on epidermis, vascular bundles. The crystallinity index of residual cellulose microcrystalline was widely enhanced because amorphous hemicellulose was removed off while crystalline was changeless. Under hot acid solution reaction, amorphous hemicellulose was hydrolyzed and leaving larger perfect cellulose thus increasing of crystalline size. Those available cellulose was obvious exposed after acid treatment and gave intensive characteristic peak on pyrogram analyzed by pyrolysis–GC–MS. 相似文献
8.
回顾了自1982年以来庆阳地区草地畜牧业从实施飞播牧草项目、草地牧业综合发展示范项目到实施中国--欧盟过渡期奶类项目所走过的路程,通过总结和认真思考,提出了“九五”到2010年草地畜牧业的思路,发展布局和重点,以及奋斗目标。 相似文献
9.
近年来,随着对病原微生物和各种传染性疾病研究的深入,我国生物实验室数量越来越多,完善实验室生物安保体系对于保护科研人员和社会安全具有重大意义。本文首先明确了实验室生物安保和实验室生物安全的区别与联系,而后指出我国存在生物安保相关法规制度不完善,实验室实施环节生物安保能力较为薄弱等问题,并借鉴WHO和部分发达国家的生物安保法规以及实施现状,提出了完善制度法规,加强实验室实施环节能力建设,强化生物安保培训,加强风险评估认识等适合我国生物安保发展现状的相关建议,以期为完善我国生物安保体系,加快生物安保发展提供参考。 相似文献
10.