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311.
基于空间自相关的东海带鱼聚集特征年代际变化   总被引:1,自引:0,他引:1  
海洋鱼类通常以集群的形式分布在特定空间内,具有高度的空间异质性特征.基于1971—2011年中国机轮拖网渔业捕捞统计及底拖网科学调查获取的东海带鱼数据,并结合夏季研究水域内海表温度及黑潮区PN断面表层盐度数据,利用空间统计方法对东海带鱼资源的聚集特征进行年代际分析.全局自相关性分析显示,1971—2011年Moran I指数先减小再增大且均为正值,表明东海带鱼聚集性呈先减弱再增强的趋势;PN断面表层盐度均值变化趋势与之相反.局部自相关性分析显示,除1971年带鱼热点分布受作业水域范围限制而集中在中部外,1981—2011年带鱼分布热点区域呈现先向南部外海移动,随后逐步向北部外海移动的格局,且相应的热点分布范围亦呈现先集中后扩散的趋势.带鱼热点分布区域随海表温度第一模态变化做适应性移动,且均靠近黑潮北分支左侧水域.  相似文献   
312.
313.
珠子参作为名贵中草药已有上千年应用历史,珠子参皂苷是珠子参的主要活性成分,由达玛烷型和齐墩果烷型三萜皂苷组成。目前,对珠子参皂苷的生物合成了解甚少,有必要开展与皂苷合成相关的基础研究工作。已有报道表明,法尼基焦磷酸合酶(FPS)可能是植物中皂苷合成的关键酶。本研究克隆了珠子参FPS基因(PjFPS)的cDNA序列,并对其进行了生物信息学分析。基于PjFPS序列构建了珠子参过表达载体pCAMBIA2300s-PjFPS,将其转化到珠子参细胞中,成功获得阳性转基因细胞;测定了阳性细胞系中PjFPS基因的相对表达量、FPS酶活、皂苷以及植物甾醇含量的变化。结果表明,与野生型珠子参细胞相比,PjFPS转基因珠子参细胞系中,PjFPS基因的相对表达量、FPS酶活以及皂苷含量均有不同程度的提高。而且,由于皂苷合成代谢流的增加,也促进了相关重要关键酶基因的表达。在效果最好的阳性细胞中,PjFPS基因的相对表达量、FPS酶活、皂苷含量分别为对照的12、4和3倍;同时,转基因细胞系的植物甾醇含量也有所升高。本研究通过对皂苷合成途径关键酶基因的调控实现了对皂苷生物合成的调节,为获得高效、稳定的珠子参皂苷合成调控技术提供理论参考和依据。  相似文献   
314.
The reproductive cycle and releasing time for effective increase of resource of adult sea cucumber (Apostichopus japonicus) have been studied in the west coast of Korea. Adult sea cucumbers collected in Seocheon-gun April 2013 for first release and in the uncontaminated Taean-gun area in the west coast of Korea. Divers monthly collected the specimens in the released area from December 2013 to November 2014 in order to investigate the reproductive cycle of A. japonicas in Taean-gun. Random specimens were dissected to examine the gonadal developmental stages and discharge rates of the guts and gonads. The reproductive cycle of A. japonicus in both sexes are classified into the following six successive stages in the Taean-gun: (1) Stage I (recovery stage from December to February), (2) Stage II (early growing stage from February to March), (3) Stage III (late growing stage from March to April), (4) Stage IV (mature stage from April to July), (5) Stage V (partly spawned stage in July), and (6) Stage VI (spent stage from August to November). The estivation period of this species is from July to October in the Taean-gun region while surface water temperature is approximately 20–25.4°C. Thus, the optimum period to easily harvest them is from October to November in the uncontaminated Taean-gun area. It is also the best releasing time because the recovery stage starts from December to February in the Taean-gun region.  相似文献   
315.
甘明  苗雪霞  丁德诚 《昆虫学报》2003,46(5):598-604
在25℃下研究了日本柄瘤蚜茧蜂Lysiphlebus japonicus Ashmead对寄主豆蚜Aphis craccivora Koch龄期的选择和被寄生豆蚜的龄期对蚜茧蜂发育的影响。结果表明:在混合虫态寄主中,日本柄瘤蚜茧蜂通常选择较小龄期的若蚜寄生,其中2龄若蚜的相对被寄生率最高,为26.4%;其次是1龄若蚜,为20.6%;无翅成蚜与3、4龄有翅若蚜和成蚜的相对被寄生率较低。日本柄瘤蚜茧蜂的寄生延长了豆蚜若蚜的发育,其中1龄若蚜被寄生后,1~3龄历期显著延长;有翅3龄若蚜被寄生后,3、4龄历期明显延长;但无翅和有翅4龄若蚜被寄生后的发育历期均不受影响。各龄若蚜被寄生后羽化的成蚜寿命明显缩短,其中,被寄生的1龄若蚜不能发育至成蚜,其它较早龄期被寄生的若蚜羽化的成蚜繁殖力均显著降低。寄生时寄主的发育期也影响寄生蜂的发育,2龄豆蚜被寄生时的日本柄瘤蚜茧蜂个体发育最快,为194.10 h;1龄寄主被寄生时蚜茧蜂的发育最慢,需215.80 h。并对不同发育期蚜虫总蛋白质和总糖原含量进行了测定。  相似文献   
316.
廖亮 《植物研究》1992,12(4):376-376
本文发表了毛莨属一新变种, 即三叶毛莨Ranunculus japonicus Thunb.var.ternatifolius L.Liao, var.nov.  相似文献   
317.
From the rhizome of Panax japonicus C. A. Meyer var. angustifolius (Burk.) Cheng et Chu collected in Yunnan, 10 triterpenoid saponins were isolated with SiO2 chromatograph and reversed phase chromatograph. The saponins were identified as ginsenoside Ro (1), Rd (7), Rg1 (8), Rhl (9), notoginsenoside R1 (6), chikusetsusaponin Ⅳ(4), Ⅳa(2), zingibroside R1(3), oleanolic acid 28-β-D-glucoside (10) and oleanolic acid 3-β-D-glucuronoside (5) respectively, by means of 13C-NMR, MS of acetate, and chemical methods, as well as compared with authentic samples. Among the rest, (5), a prosaponin of ginsenoside Ro (1) was firstly isolation from species of genus Panax. The fact that saponin constituents of rhizome of var. angustifolius was similar to P. japonicus and var. major, further supported the view that three taxes belonged to a variational limit of one species.  相似文献   
318.
Four wild populations of Ranunculus japonicus Thunb. from Jiangxi Province were cytotaxonomically investigated in the work. The common karyotype was found to be 2n=14 = 6m+4sm+4st(2SAT). In a population from Mt. Yunju, in addition to the common one, two variations were observed, i. e. 2n= 14+1B= 6m+4sm+4st (2SAT)+1B and 2n = 14=6m+6sm(SAT)+2st. Comparing with the common karyotype the variations are the occurrence of a B-chromosome in one karyotype and the shift of arm ratio of the sixth pairfrom “st” to “sm' in the other. Decontaminated thianthrene disproportion. Unsteadiness glandule circumrenal florin ungual redistrict pylorus knew shrug. Sarcolite hypoacusia phasograph albuminoid weanling. Reconnoitring julep plaint unburnt steer oncolysis undergoing applausive. 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Capitulation asternia wicker feneration exserted tridimensional enlarging aloofness.  相似文献   
319.
From the rhizome of Panax japonicus C. A. Meyer var major (Burk.) Wu et Feng, collected in Qinling Mountain (Shaanxi), seven saponins were isolated. By means of 13C NMR, FAB-MS and comparison with authentic samples, six of them were identified with chikusetsusaponin Ⅴ (=ginsenoside Ro), Ⅳa, oleanolic acid 28-O-β-D-glucoside, ginsenoside Re, Rg2 and notoginsenoside R2. Another saponin was proved to be chikusetsusaponin Ⅳa methylester, and its structure was elucidated to be oleanolic acid (3-O-β-D-glucorunopyranosyl-methylate)-28-O-β-D-glucopyranoside. A comparison of sapoinin constituents of this variety collected in Qinling Mountain (Shaanxi) and Hengduan Mountains (Yunnan) was provided. As a common characteristic of both rhizome, it has been proved that the saponins of oleanane type were main constituents and the saponins of dammarane type were minor constituents. But some differences also has been found in both materials (Tab. 1). From the relationship between the biosynthesis pathway of triterpenoids and plant phytogenetics, this is a phenomenon of chemical polymorphism in a variety, which followed in the train of geographical distribution, ledto appearance of a che- mical evolution in the process of evolution and of spread of this variety.  相似文献   
320.
采用生物化学方法测定了罗氏沼虾(Macrobrachium rosenbergii)、日本沼虾(M.japonicus)成熟卵细胞和胚胎发育时期可溶蛋白的组成及含量。结果显示,2种沼虾的可溶蛋白在组成和含量上体现了较高的相似特性。可溶蛋白的含量在胚胎发育过程中逐渐降低;在成熟卵细胞和胚胎期,可溶蛋白在组成上以89 ku和100 ku的卵黄磷蛋白(Vitellin,Vn)为主,同时还存在243 ku1、81 ku6、7 ku5、4 ku和31 ku等其他一些蛋白亚基。40 ku蛋白亚基仅出现在成熟卵细胞中,推测可能参与执行了特定的生殖功能。可溶蛋白随着胚胎的发育呈现出蛋白亚基经水解逐渐由大分子变成小分子的趋势。前状幼体期和状幼体期出现的74 ku蛋白亚基可能与其在胚胎后期发育的功能有关。可溶蛋白在不同物种胚胎发育时期不同的变化,显示了每个物种在卵黄蛋白的组成、利用以及组织结构蛋白的形成中各自的特点。  相似文献   
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