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131.
132.
李万程 《湖南师范大学自然科学学报》1985,(4)
用聚丙烯酰胺凝胶盘状电泳分析了荷包红鲤、湘江野鲤和其杂交一代血清、肌肉、肝脏和肾脏4种组织的酯酶同工酶谱。实验结果表明:荷包红鲤和湘江野鲤虽隶属同一个种的不同生态群,但其对应组织的酯酶同工酶谱差异明显;杂交F_1代的血清和肌肉组织表现了亲本双方的酯酶同工酶,但肝脏和肾脏的酯酶分别与父、母本相似。由此可见,酯酶同工酶是鲤鱼种内杂交育种中,亲本及后代鉴定的有效标志。同时,根据亲本和后代的酯酶同工酶谱,可以解释杂交一代某些杂种优势现象。 相似文献
133.
Molecular cloning of growth hormone receptor (GHR) from common carp(Cyprinus carpio L.)and identification of its two forms of mRNA transcripts 总被引:1,自引:0,他引:1
Growth hormone receptor (GHR) belongs tothehematopoietic receptor superfamily[1]. The action ofgrowth hormone (GH) in regulating growth[2],re-production[3]and i mmunity[4]has been elucidated.The binding of GHtothe GHRontarget tissues trig-gers a cascade of tyrosine and protein phosphorylationevents, which cul minates in the biological action ofGH[5 ,6]. Up to date GHR cDNAs have been clonedfrom many species[7—9],including various kinds ofmammalian ani mals ; avian of chicken and domest… 相似文献
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SUN Yuandong TAO Min LIU Shaojun ZHANG Chun DUAN Wei SHEN Jiamin WANG Jing ZENG Chen LONG Yu LIU Yun 《自然科学进展(英文版)》2007,17(2):163-167
Gynogenetic diploid was induced in red crucian carp (RCC) ( Carassius auratus Red Variety) eggs using UV-irradiated spermatozoa from blunt snout bream (B) (Megalobrama amblycephaia) or from mirror carp (C) (Cyprinus carpio. L) . Spermatozoa were genetically inactivated by an appropriate UV dosage, and then the maternal DNA was duplicated with cold shock at 0-4℃. When using the spermatozoa of B, the fertilization rate, hatching rate and survival at first feeding were 52. 6±3. 0 %, 23.6±4.1 % and15.7±3.4 % , respectively, and the survival at first feeding was significantly higher than that (11.3±2.2%) when using the spermatozoa of C (Cyprinus carpio. L). According to the morphological characteristics, the chromosome number and the degree of gonadal development, gynogenetic RCC could be distinguished from the control hybrids of RCC♀×B♂. The individuals with red body color, 100 chromosomes and normal gonadal development were successful gynogenetic RCC, while the individuals with 124 or 148 chromosomes and delayed gonadal development were hybrids of (RCC×B). The triploid hybrids (RCC×B) (2 years old) were sterile, but the tetraploid hybrids (RCC×B) were sexually mature age of two. In the present study, compared to the spermatozoa of C, the advantages of spermatozoa of B as the activation source were that could increase the survival at first feeding of gynogenetic individuals and simplify the confirmation of gynogenetic status, which suggested that the sperm of B was an effective activation source for inducing gynogenesis in crucian carp. 相似文献
137.
SUN Yuandong TAO Min LIU Shaojun ZHANG Chun DUAN Wei SHEN Jiamin WANG Jing ZENG Chen LONG Yu LIU Yun 《自然科学进展》2007,17(2):163-167
Gynogenetic diploid was induced in red crucian carp (RCC) (Carassius auratus Red Variety) eggs using UV-irradiated spermatozoa from blunt snout bream (B) (Megalobrama amblycephala) or from mirror carp (C) (Cyprinus carpio. L). Spermatozoa were genetically inactivated by an appropriate UV dosage, and then the maternal DNA was duplicated with cold shock at 0-4℃. When using the spermatozoa of B, the fertilization rate, hatching rate and survival at first feeding were 52.6±3.0 %, 23.6±4.1 % and 15.7±3.4 %, respectively, and the survival at first feeding was significantly higher than that (11.3±2.2%) when using the spermatozoa of C (Cyprinus carpio. L). According to the morphological characteristics, the chromosome number and the degree of gonadal development, gynogenetic RCC could be distinguished from the control hybrids of RCC♀× B♂. The individuals with red body color, 100 chromosomes and normal gonadal development were successful gynogenetic RCC, while the individuals with 124 or 148 chromosomes and delayed gonadal development were hybrids of (RCC× B). The triploid hybrids (RCC× B) (2 years old) were sterile, but the tetraploid hybrids (RCC× B) were sexually mature age of two. In the present study, compared to the spermatozoa of C, the advantages of spermatozoa of B as the activation source were that could increase the survival at first feeding of gynogenetic individuals and simplify the confirmation of gynogenetic status, which suggested that the sperm of B was an effective activation source for inducing gynogenesis in crucian carp. 相似文献
138.
几种神经内分泌因子促进草鱼鱼种生长激素分泌和生长的作用 总被引:1,自引:0,他引:1
短期(3 D)或长期(6周)单独投喂促黄体素释放激素类似物LHRH-A(每克饵料含5ΜG),或者LHRH-A分别与促甲状腺素释放激素TRH(每克饵料含5ΜG)、多巴胺激动剂APO(每克饵料含1 MG)、多巴胺D-1型受体激动剂SKF(每克饵料含0.5 MG)混合投喂,都能显著提高草鱼鱼种的血清GH水平,并能促使鱼体生长率和食物转化率显著提高。LHRH-A分别与TRH、APO和SKF的协同作用要比它的单独作用较能有效的促进草鱼GH分泌和鱼体的生长。这些研究结果表明,通过投喂方式,一些刺激脑垂体GH分泌的神经内分泌因子,能被草鱼鱼种消化道直接吸收进入血液循环,并保持生物活性,使草鱼鱼种血清GH水平升高,进而提高食物转化率,使生长速率加快。因此,将一些促进GH分泌的高活性神经内分泌因子,以适当的剂量添加到鱼类饵料中,提高鱼苗和鱼种的生长率与成活率,在鱼类养殖生产中有良好的应用前景。 相似文献
139.
自然条件下,以三倍体牡丹品种首案红和二倍体品种白玉为实验材料,测定叶片的光合日变化和光响应,结果表明:二者的净光合速率的日进程均为双峰型曲线,首案红一天当中的平均净光合速率、光饱和点和光补偿点均大于白玉,同时光饱和点的最大光合速率首案红12.39μmol/(m2.s)高于白玉6.28μmol/(m2.s)。该研究从光合生理角度显示,首案红比二倍体白玉具有较强的光合能力。 相似文献
140.
晚唐时期,在客观环境的压力之下,士人在仕、隐、逸的选择上大都不是出于自觉自愿,而是无奈之举.吴融的诗歌所表现出来的心态特点正是上述群体心态的个案表征.首先,诗人有强烈的入仕之心,痴心地在仕宦的道路上艰难行走.其次,在游学羁旅、仕宦坎坷中,诗人又不免产生遁世的愿望.再次,在用世无成、隐而不得的状况下,受当时社会风气的影响,吴融抒写的艳情诗歌又暴露了诗人及时行乐的思想. 相似文献