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81.
高温条件下复合抗应激剂对肉鸡的影响 总被引:5,自引:0,他引:5
本文研究了高温条件下复合抗应激剂对肉鸡的影响。结果表明:经历32 ℃一周的5 ~8 周龄肉鸡采食量、增重、饲料转化率均显著下降(P< 0 .01) ,饮服复合抗应激剂显著改善增重和饲料转化率(P< 0 .01) , 采食量未见明显改变,饲料转化率达到常温水平。32 ℃16 小时血浆皮质酮、T3 显著下降(P< 0 .01) 、T4 显著升高(P< 0 .01) ;32 ℃120 小时血浆皮质酮、T3 升高并超出常温组(P< 0 .05) 、T4 较16 小时下降但仍高出常温组(P< 0 .05) 。饮服复合抗应激剂时血浆皮质酮、T3 、T4 显现相同变化规律,但这种变化得到显著缓解 相似文献
82.
《Plant Production Science》2013,16(3):178-183
AbstractLeaf sheaths of rice plants are known to temporarily accumulate starch prior to heading, which is subsequently remobilized and transported into the panicle after heading. We investigated the time course for both carbohydrate content and steady state mRNA levels of enzymes related to starch and sucrose metabolism in the rice leaf sheath (Oryza sativa L. cv. Nipponbare). Leaf sheaths from the second leaf below the flag leaf accumulated high levels of starch before heading but they rapidly decreased after heading. In contrast, the flag leaf sheath did not accumulate as much starch. In the second leaf sheath, the mRNA levels of enzymes involved in starch synthesis, ADP glucose pyrophosphorylase (EC 2. 7. 7. 27), soluble starch synthase (EC 2. 4. 1.21) and branching enzyme (EC 2. 4. 1. 18) were high before heading, which coincided with rapid accumulation of starch. The mRNA levels of sucrose synthesis enzymes, cytosolic FBPase (EC 3. 1. 3. 11) and sucrose phosphate synthase (EC 2. 4. 1. 14), and the sucrose transporter (OsSUTI) increased at the time of heading, which was largely coincident with a decrease in the mRNA levels of starch synthesis enzymes. In the flag leaf sheaths, changes in mRNA levels of starch synthesis enzymes were not pronounced, however mRNA levels of sucrose synthesis enzymes and the sucrose transporter showed a clear increase throughout the heading period. The different characteristics observed between the two leaf sheaths will be discussed in relation to the sink to source transition. 相似文献
83.
制备了邻菲口罗啉化学修饰碳糊电极,在含噻吩甲酰三氟丙酮的HAc-NaAc体系中,Co(Ⅱ)离子经化学富集在电极表面上形成三元络合物.采用2.5次微分伏安法测定痕量Co(Ⅱ)离子.Co(Ⅱ)浓度在8.0×10-9~7.0×10-7mol·L-1范围内与阳极溶出峰峰高成良好的线性关系,检出限达1.2×10-9mol·L-1.电极用于水样中钴的测定,结果令人满意. 相似文献
84.
张海英 《湖南农业大学学报(自然科学版)》2008,(4)
简化字已推行了五十多年,但被简化了的繁体字、异体字却频频出现在各种简体版的出版物特别是学术期刊中,导致期刊用字极不规范。以随机抽取的数种期刊为例,具体分析了其中被错误使用的繁体字、异体字,并简单讨论了错误使用的原因,提出了改变这种繁简乱用的混乱状况的建议。 相似文献
85.
采用RT-PCR方法从小麦品种豫教2号发育的籽粒中克隆出淀粉合酶I基因(starch synthase I,SSI)部分cDNA片段(795 bp)(GenBank No.EF221762),同源性比较结果显示,它与GenBank上已报道的SSI基因有高度同源性。以p WM101质粒为基础,构建了由35S启动子调控的SS I基因的反义表达载体p WM101SSI;另外,还以pFGC5941质粒为基础,构建了SSI基因的RNAi载体pFGC5941SSIsa,这些载体的构建为研究此基因的功能奠定了基础。 相似文献
86.
本研究用睾丸组织切片和细胞悬浮液制备的减数分裂与联会复合体标本,观察研究了公牛扁牛减数分裂及精子发生过程。与以往的研究结果不同的是,发现有些公牛扁牛的部分精母细胞能够完成减数分裂的全过程,直至出现精子。但在整个过程中伴随着大量异常,破坏了精子生成的机能。 相似文献
87.
ABSTRACT: The nucleotide sequences of Japanese flounder Paralichthys olivaceus , major histocompatibility complex (MHC) cDNA, classical MHC class Iα, non-classical MHC class Iβ, MHC class IIα and IIβ, were determined. The domain structures and antigen binding motifs of vertebrate MHC are conserved in the Japanese flounder MHC. A phylogenetic analysis supports the classification of these genes into class I and class II MHC. Classical MHC class Iα was ubiquitously expressed, whereas the non-classical MHC class Iβ was expressed mainly in lymphoid organs, gills, intestine and stomach. The MHC classes IIα and IIβ were also ubiquitously expressed. 相似文献
88.
89.
Andr Neveu 《Aquaculture (Amsterdam, Netherlands)》2009,295(1-2):30-37
European countries are probably the greatest consumers of frogs' legs, although this is occurring in a context of amphibian decline. Imports of frogs' legs have been increasing over the last few decades in relation to the development of deep-frozen products. This demand has stimulated farming with neotropical species for international trade. Today, in spite of some trials on European species, no production is effective. From the early 1990s, small-scale experimental rearing trials have been undertaken in Brittany (France) with a local green frog belonging to the esculenta complex (Rana ridibunda) which accepts granulated feed. This complex comprises two Mendelian species R. lessonae (LL) and R. ridibunda (RR) as well as their hybridogenetic hybrid Rana esculenta, which can be either diploid (RL) or triploid (RLL, RRL).The purpose of this study is to analyse the ability of each taxon to be reared. During the two months following metamorphosis, froglets were trained to eat pellets. The surviving individuals were reared for one year under regulated conditions to estimate the survival rate, growth and production of each frog type.The results show low survival rates (14.8 to 26.2%) for LL and RLL, higher rates (39–46.4%) for F1 and F2 from wild RR and RLL, with the highest rates (63.0 to 77.4%) for RL, RRL and all RR, using data from several years of rearing. After three years under rearing conditions, the adult survival rate is highest for rearing strain RR-Rivan 92* (53.7%). The growth rate varies greatly according to phenotype, and only frogs with an RR phenotype reach marketable size. In the wild, LL exhibits some difficulty in reaching this limit. As a result, production increases from 1.5–8.7 kg/m2 for individuals with an L hemiclone to 22.9–35.7 kg/m2 for each cohort of phenotype RR from at least two generations under rearing conditions.In relation to hybridogenesis processes, hybrids with diploid or triploid genomes do not seem to offer any advantage for production purposes. However, R. lessonae individuals from intensive rearing can produce fertile eggs and tadpoles, which could enable production for restocking to preserve wild diversity or build up new populations in suitable habitats. 相似文献
90.
采用聚丙烯酰胺凝胶电泳技术,研究了中性条件下[CuL(Cl)](C lO4)与马心肌红蛋白的选择性水解切割反应,L为2-[二(2-氨乙酸)氨基]乙醇.结果表明,[CuL(Cl)](ClO4)对马心肌红蛋白显示出较高的切割选择性和切割效率,且切割效率与浓度、介质条件、温度、温育时间有一定的相关性. 相似文献