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双语推荐：变态

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为棘胸蛙的人工养殖提供参考，进行了不同饲养密度、光照、水温环境因子对棘胸蛙蝌蚪变态的影响试验。结果表明：密度为700尾／6m2时，蝌蚪成活率为83．14％，成活变态率和总变态率均最高，分别达91．41％和76．0％；光照强度为2000～3500 lx／d 时，蝌蚪成活率、成活变态率和总变态率均最高，分别达85．00％、91．24％和77．56％；养殖水温为（23±0．5）℃时，蝌蚪成活率为93．89％，成活变态率和总变态率均最高，分别达92．90％和87．22％。
The effect of different breeding density,illumination intensity and water temperature on metamorphosis of P .spinosa tadpole was studied to provide a reference for artificial breeding of P .spinosa tadpole.The survival rate,survival metamorphosis rate and total metamorphosis rate of P .spinosa tadpoles is 83.14%,91.41% and 76.0% respectively when breeding density is 700 tadpoles/6m2 .The survival rate,survival metamorphosis rate and total metamorphosis rate of P .spinosa tadpoles is 85.00%, 91.24% and 77.56% separately when illumination intensity is 2 000 ~ 3 500 lx/d.The survival rate, survival metamorphosis rate and total metamorphosis rate of Paa spinosa tadpoles is 93.89%,92.90% and 87.22% respectively when water temperature is 23±0.5 ℃.

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河工模型试验中,变态河工模型量测的断面平均流速与正态河工模型量测的断面平均流速有一定的偏离,变率取值越大,变态模型的断面平均流速与正态模型的断面平均流速偏离度越大。通过同变率典型工程模型试验得出:变态模型的断面平均流速总体大于正态模型的断面平均流速。变态河工模型断面平均流速偏离度受变率选取、边界条件及流量大小影响,边界顺直、水流平稳处,变态模型的断面平均流速偏离度小于20%;边界变化较大、流态紊乱处,变态模型的断面平均流速偏离度大于20%。
In river model experiment, the section average flow velocity is different between distorted river model and normal model, the deviation degree of average flow velocity increases with the increase of dis-torted rate. The typical construction experiment shows that the section average flow velocity of distorted river model is faster than normal model; it is affected by distorted rate, boundary conditions and flow. The deviation degree of section average flow velocity is less 20% in boundary straight and flow smoothly, other-wise the opposite.

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系统研究了我国本土两栖动物种黑斑蛙(Rana nigromaculata)变态发育过程中甲状腺组织学和甲状腺激素水平的变化,为甲状腺生物学和甲状腺干扰研究提供基础数据。黑斑蛙蝌蚪发育的形态变化:第26—40阶段,后腿芽生长并逐渐分化出五趾结构;42阶段,开始进入变态高峰期,前肢展开,尾吸收,蝌蚪身体发生巨大形变;46阶段,蝌蚪完全变态成小蛙。随着形态学的变化,甲状腺的组织结构也发生明显的变化:26—37阶段,甲状腺体积较小,增长缓慢;38阶段甲状腺体积迅速膨大,进入高峰期,甲状腺的发育达到顶峰;随着变态完成,甲状腺又逐渐缩小。甲状腺组织学变化的同时,甲状腺激素水平也相应发生变化:在变态前期,下颌中3,3’,5-三碘代-L-甲腺原氨酸(T3)水平增长缓慢,进入变态期后,T3含量迅速升高,在变态高峰期达到峰值,随后下降。以上结果表明,黑斑蛙发育过程中甲状腺组织学的变化与甲状腺激素水平的波动相吻合。对黑斑蛙甲状腺系统的研究,可为日后使用黑斑蛙开展甲状腺干扰作用的研究提供基础。
The metamorphosis of amphibians is considered as a good model to study thyroid hormone (TH) disruption. In the present study, we used Rana nigromaculata, a domestic species, to investigate thyroid development and the changes in TH levels during metamorphosis.We first described the morphological change during the tadpole develop-ment (stage 26-46) that the hind limbs appeared and finally formed five toes from stage 26 to 40. At the climax of metamorphosis, the dramatic changes include the protruded forelimbs and start-to-resorb tail. Tail resorption completed at stage 46, indicating the completion of metamorphosis. Corresponding to the morphological changes, histological fea-tures of thyroid gland changed significantly. From stage 26 to 37, the thyroid gland was small and developed slowly. At stage 38, the thyroid gland enlarged dramatically. The climax of thyroid gland development happened at the climax of metamorphosis. The thyroid gland began to shrink at the completion of metamorpho

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采用常规生物化学分析方法研究了硬壳蛤的卵、D形幼虫、变态前幼虫和变态后幼虫的蛋白质、脂类、和碳水化合物的含量及发育过程中能量利用情况。试验结果显示,硬壳蛤卵中蛋白质、脂类和碳水化合物的含量分别为47.6%、42.2%和10.2%;每个卵所含的能量平均为0.988mJ。经过24h的孵化后,3种能源物质的含量均下降,蛋白质、脂类和碳水化合物相对下降12.5%、18.8%和13.9%,总能源物质含量下降15.3%。胚胎发育过程中每个幼虫平均消耗的能量为0.161mJ,其中脂类提供了68.5%的能量。幼虫变态过程中,蛋白质、脂类和碳水化合物相对下降25.1%、26.6%和19.2%。变态过程中每个幼虫消耗的能量为2.111mJ,蛋白质、脂类和碳水化合物分别提供了能量的44.4%、35.9%和19.2%。变态过程消耗的能量是胚胎发育过程的13倍。
The levels of protein , total lipid and carbohydrate and energy utilization were studied in fertilized eggs , D-shaped larvae , and premetamorphic , and postmetamorphic larvae of hard clam (Mercenaria mercenaria) .The results showed that the fertilized eggs was composed of 47 .6% protein , 42 .2% lipid ,and 10 .2% carbohydrate ,with average energy of 0 .988 mJ per egg .Twenty-four hours after fertilization ,there were decrease in approximate composition at a rate 12 .5% of protein ,18 .8% of lipid , 13 .9% of carbohydrate ,and 15 .3% of energy per egg .During embryonic development ,total energy of 0 .161 mJ was expended by an embryo ,in which 26 .0% derived from protein ,68 .5% from lipid ,and 5 .4% from carbohydrate .During the metamorphosis , 25 .1% protein , 26 .6% lipid , and 19 .2%carbohydrate were exhausted by the larvae ,2 .111 mJ individually ,accounting for 44 .4% in protein , 35 .9% in lipid and 19 .2% in carbohydrate .The energy consumption was found in the metamorphosis as

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利用自然海水和天然饵料,采用无泥砂采苗方法,在天津沿海成功开展了青蛤工厂化育苗。幼虫初始壳长(120±1.28)μm,壳长平均日增长5.05μm,成活率23.0%;第19~31d为变态期,壳长平均日增长14.1μm,变态率32.9%;变态后至第53d,壳长平均日增长32.5μm,成活率82.3%。本次育苗试验充分利用天津沿海水质条件与环境特点,改进育苗方法,建立了适于天津海区的青蛤人工育苗工艺,共得到双水管稚贝约1.25亿枚。
Factory breeding of Cyclina sinensis was successfully carried out in Tianjin coast by the u-sing natural sea water ,natural food and settlling without mud and sand .In the larval stage ,the initial shell length of larvae was 120 ± 1 .28 μm ,the average daily growth of shell length was 5 .05 μm ,the survival rate was 23 .0% ;During 19~31 day in which larvae were in metamorphosis stage ,the average daily growth of shell length was 14 .1μm ,metamorphosis rate was 32 .9% ;From metamorphosis to 53 day ,the average daily growth of shell length was 32 .5 μm ,the survival rate was 82 .3% .The breeding experiments take advantage of water quality conditions and environmental characteristics in the Tianjin coast ,improve breeding methods ,and establish the Cyclina sinensis breeding method in the Tianjin coast .In total ,about 125 million double siphon juveniles were harvested .

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以海洋橙品系( O)和珍珠白品系( W)蛤仔Ruditapes philippinarum为试验材料,采用双列杂交方法建立自交组OO、 WW和杂交组OW、 WO,研究了子一代蛤仔在不同发育时期生长、存活、变态的杂种优势及壳色遗传机制。结果表明：杂交组WO获得了一定程度上的单亲生长优势,杂交组OW在浮游期和变态期表现出生长优势,在稚贝期却表现出生长劣势,但正反交组总体上获得了一定程度的中亲生长优势；在存活率方面,正反交组的中亲存活优势和杂交组WO的单亲存活优势均表现出积极的一面,杂交组OW除了在3、6日龄时表现出一定的单亲存活劣势外,在其他日龄时均表现出存活优势；在变态期,正反交组的变态率表现出一定的中亲及单亲杂种优势；综合生长、存活率和变态率三方面来看,正反交组的杂种优势大小顺序均为WO>OW。研究表明,杂交组蛤仔生长和存活的杂种优势主要受到卵源(母本)效应的影响,且卵源(母本)效应不仅存在于幼虫期,还贯穿于变态期和稚贝期。橙色品系自交组后代壳色分离比(橙色.白色)符合3.1,与壳面颜色为隐性纯合子的珍珠白品系杂交的后代壳色分离比(橙色.白色)符合1.1,遵循孟德尔遗传定律,说明橙色对白色为显性,壳色是由简单的遗传基因控制,且与控制壳面花纹或条带的遗传基因不在同一
The 2í2 diallel cross of different shell color for Manila clam Ruditapes philippinarumstrains, two self-fertilized groups ( OO, WW) and two hybrid groups ( OW, WO) were conducted using orange strain ( O) with or-ange shell color and white strain ( W ) with white shell color to investigate the heterosis of growth, survival, meramorphosis and shell color determinism for offsprings. The results showed the positive single-parents growth heterosis of WO was observed in all stages, the same as OW expected the juvenile stage. The hybrid groups own the certain degree mid-parents growth heterosis. There were strong middle and single parent survival heterosis in hybrid groups. On metamorphic stage, the positive heterosis of metamorphosis was observed. In a word, the heterosis of WO was larger than that OW. The egg origin ( maternal) effects were the main factor influencing heterosis of growth and survival at all of stages. The shell color segregation ratio ( orange :white ) of self-fe

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在生化培养箱中,分别设置5、10、15、20、25、30、35、40、45共9个盐度梯度及0、5、10、15、20、25、30、35、40℃9个温度梯度,借助SPSS 17.0分析骤变、渐变及恢复试验结果对中华虎头蟹溞状幼体存活及变态的影响,探讨中华虎头蟹溞状幼体对盐度、温度的适应性。试验结果显示,骤变、渐变试验中,盐度、温度对Ⅰ、Ⅱ、Ⅲ期溞状幼体存活率及变态率的影响均达到极显著水平(P0.01);除25℃组外,其余盐度、温度渐变组变态率全部高于骤变组;Ⅱ、Ⅲ期溞状幼体耐盐、耐温及变态能力差异不大,但均显著高于Ⅰ期溞状幼体。骤变、渐变恢复试验中,盐度25和温度25℃以5/24h的变幅恢复至其他梯度时,均不显著影响Ⅰ、Ⅱ、Ⅲ期溞状幼体的存活率;溞状幼体的恢复能力Ⅰ期Ⅱ期Ⅲ期,但差异不大。
The effects of sharp and gradual changes in salinity (5 ,10 ,15 ,20 ,25 ,30 ,35 ,40 ,and 45) and temperature (0 ,5 ,10 ,15 ,20 ,25 ,30 ,35 ,and 40 ℃)on survival and metamorphosis in zoea of Chinese tiger crab Orithyia sinica were studied in a biochemical incubator by testing recovery to evaluate the adaptability of salinity and temperature by SPSS17 .0 .The results showed that the sudden and gradual changes in salinity and temperature led to significantly affect the larval survival and metamorphosis ( P zoeaⅡ >zoea Ⅰ .

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【目的】昆虫变态发育的启动主要受前胸腺合成分泌的蜕皮激素所调控,而蜕皮激素的合成是由细胞色素P450基因催化完成。家蚕(Bombyx mori)是一种产丝昆虫,蚕业生产中如果能阻断或延迟家蚕蛹变态发育进程,将有利于改进蚕茧处理工艺,提高蚕丝品质。论文旨在鉴定参与家蚕蜕皮激素合成的细胞色素P450基因,从而为人为遗传调节家蚕变态发育提供靶基因。【方法】基于序列同源性比对,筛选家蚕及其他昆虫中参与蜕皮激素合成的P450基因。利用ClustalW软件,分析昆虫蜕皮激素合成相关P450基因的遗传发生关系。通过全基因组表达芯片数据分析及RT-PCR验证,调查家蚕蜕皮激素合成相关P450基因的时空表达特征。利用RNAi技术分析Cyp314a1表达下调对家蚕变态发育的影响。【结果】家蚕基因组中有4个参与家蚕蜕皮激素合成的P450基因,即Cyp306a1、Cyp302a1、Cyp315a1和Cyp314a1。比较分析显示,这4个蜕皮激素合成相关的P450基因在家蚕及其他昆虫中都是单拷贝,而且每个基因的同源体在遗传发生树上能很好地聚成一类,表明昆虫蜕皮激素合成相关的P450基因及其负责的蜕皮激素合成通路非常保守。时空表达谱分析显示,在家蚕幼虫5龄第3天,Cyp302a1、Cyp315a1和Cyp314a1主要在家蚕幼虫卵巢、精巢和头部等组织器官中高表达;在幼虫-蛹-成虫变态发育进程中,Cyp302a1、Cyp315a1和Cyp314a1主要在蛹变态发育后期表达,其中Cyp314a1分别在上簇、化蛹及羽化前高表达,这与蜕皮激素滴度高峰出现的时期基本一致。Cyp314a1的RNAi导致家蚕不能正常化蛹及雌蛾卵巢发育异常,且降低了蜕皮激素信号通路关键基因HR3及Ftz-f1的表达。【结论】家蚕蜕皮激素合成相关的P450基因在进化上非常保守,其表达水平降低能引起家蚕蛹变态发育受阻,暗示蜕皮激素合成相关P450基因可以用作家蚕变态发育控制的靶标基因之一。
[Objective]Insect metamorphosis is initiated by ecdysone, which is synthesized in prothoracic gland through cytochrome P450 enzymes-catalyzed enzymatic reactions. Silkworm (Bombyx mori) is a silk-producing insect. Interrupting or delaying the pupa-adult transition in silkworm will help to reform the flow of silkworm cocoon-processing and to further improve the quality of silk. The objective of this study is to identify and characterize P450 genes involving in ecdysteroidogenesis in silkworm and to provide candidate genes for genetic controlling of silkworm metamorphosis. [Method] Ecdysteroidogenesis-related P450 genes were identified in silkworm and other insects through sequence homology search. Phylogenetic tree of insect ecdysteroidogenesis-related P450 genes was constructed by ClustalW program. The mRNA expression profiles of ecdysteroidogenesis-related P450 genes from silkworm were checked by microarray and RT-PCR analysis. RNAi experiment was used to examine the effects of down-r

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采用浙江省苍南县养殖海区人工越冬养殖、性腺成熟的刺参为材料,观察并描述了精卵排放至稚参的整个胚胎发育和幼体变态过程,温度和盐度对其胚胎和幼体发育的影响.结果表明,在水温21℃,盐度28.6‰, pH 8.0的条件下,整个胚胎发育过程需要31 h 左右,变态发育至稚参需13~15 d.不同水温和盐度对受精卵的孵化率、胚胎发育和幼体的变态时间有显著影响.南移刺参胚胎和幼体发育适宜的水温范围为18~21℃,水温下降至15℃不能受精,适宜的盐度范围为28.6‰~32.4‰,盐度降低至20.5‰或升高至39.1‰,受精卵均不能正常发育.
The Apostichopus japonicus in artificial overwintering cultivation in southern Zhejiang Cangnan county sea area are selected to be fertilized through hasten parturition, and the cell biology phenomena, such as the fertilization, segmentation of ovum ,larval and juveniles development, are observed with the microscope. The whole process of embryonic development, larval and juveniles development of Apostichopus japonicus is recorded in detail through microscopic photography. The results show that, with 21 ℃, salinity of 28.6‰, the condition of pH 8.0, the whole process of embryonic development requires 31 h, and the metamorphosis to juveniles takes 13~15 d. There is significant influence of different temperature and salinity on hatching rate of fertilized eggs, embryos and larvae metamorphosis time. The optimum incubation temperature is found to be 18~21 ℃, It cannot be fertilized when temperature drops to 15 ℃. The optimum salinity is 28.6‰~32.4‰, and when the salinity is

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《苏茜的世界》以复仇为主题,以谋杀为主要情节,以嗜血杀戮、心理变态为主要人物形象特征,是一部充满了哥特元素的小说。
The Lovely Bones is a novel full of gothic elements,whose theme is revenge,main plot is murder and main features of char-acter images are bloodthirsty killing and psychopath.

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