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991.
992.
ZhuoHui Zhang Jie Chen Ling Li Min Tao Chun Zhang QinBo Qin Jun Xiao Yun Liu ShaoJun Liu 《中国科学:生命科学英文版》2014,57(9):889-902
Distant hybridization refers to crosses between two different species or higher-ranking taxa that enables interspecific genome transfer and leads to changes in phenotypes and genotypes of the resulting progeny. If progeny derived from distant hybridization are bisexual and fertile, they can form a hybrid lineage through self-mating, with major implications for evolutionary biology, genetics, and breeding. Here, we review and summarize the published literature, and present our results on fish distant hybridization. Relevant problems involving distant hybridization between orders, families, subfamilies, genera, and species of animals are introduced and discussed, with an additional focus on fish distant hybrid lineages, genetic variation, patterns, and applications. Our review serves as a useful reference for evolutionary biology research and animal genetic breeding. 相似文献
993.
Jianqiu Xiao Ling Zhang Jingmin Wang Yuwu Jiang Lirong Jin Jianqi Lu Li Jin Chunjiu Zhong Xiangmin Xu Feng Zhang 《Molecular genetics and genomics : MGG》2014,289(5):755-763
Rare copy number variations (CNVs) generated by human genomic rearrangements have been shown to play an important role in pathogenesis of human diseases and cancers. CNV breakpoint analysis can help define genomic location, genetic content and sequence structure of pathogenic CNVs. This process is vital to elucidate CNV mutational mechanism and etiology of CNV-associated disorders. However, it is technically challenging to map CNV breakpoints at base-pair level, especially in the genomic regions with sequence complexity. In this study, we developed a new method of capture and breakpoint approaching sequencing (CBAS) to efficiently obtain CNV breakpoint sequences. This strategy is independent of CNV structures and applicable to various CNV types. As was demonstrated in CNV-associated patients with neurological disorders, CBAS achieved fine mapping of breakpoint sequences for compound deletion, complex duplication, and translocation. Intriguingly, CBAS also revealed unexpected CNV complexity involving long-range DNA rearrangement. Our observations showed that CBAS is an efficient method for obtaining CNV breakpoint sequence and mapping insertional events as well. This method can facilitate the researches on CNV-associated human diseases and cancers. CBAS is also applicable to mapping the integration sites of retrovirus (such as HIV) and transgenes in model organisms. 相似文献
994.
Snyder DA Aramini JM Yu B Huang YJ Xiao R Cort JR Shastry R Ma LC Liu J Rost B Acton TB Kennedy MA Montelione GT 《Proteins》2012,80(7):1901-1906
The ribosome consists of small and large subunits each composed of dozens of proteins and RNA molecules. However, the functions of many of the individual protomers within the ribosome are still unknown. In this article, we describe the solution NMR structure of the ribosomal protein RP-L35Ae from the archaeon Pyrococcus furiosus. RP-L35Ae is buried within the large subunit of the ribosome and belongs to Pfam protein domain family PF01247, which is highly conserved in eukaryotes, present in a few archaeal genomes, but absent in bacteria. The protein adopts a six-stranded anti-parallel β-barrel analogous to the "tRNA binding motif" fold. The structure of the P. furiosus RP-L35Ae presented in this article constitutes the first structural representative from this protein domain family. 相似文献
995.
Larval settlement and metamorphosis of the mussel Mytilus coruscus in response to natural biofilms 总被引:1,自引:0,他引:1
Settlement and metamorphosis of pediveliger larvae of Mytilus coruscus in response to natural biofilms was investigated in the laboratory. Pediveliger larvae settled and metamorphosed in response to biofilms and post-larval settlement and metamorphosis increased with biofilm age. The activity of the biofilm was positively correlated with biofilm age, dry weight, bacterial density and diatom density, but had no apparent relationship with chlorophyll a concentration. The change in bacterial community composition corresponding to biofilm age may explain differences in the age-dependent inducing activities of biofilms, which in turn may play an important role in larval settlement in this species. 相似文献
996.
随着新一代生物质能源的研发,利用梭菌的发酵生产丁醇已成为热点。选用能生产丁醇的Clostridium acetobutylicum AS1.7,Clostridium acetobutylicum AS1.132,Clostridium acetobutylicumAS1.134和Clostridium beijerinckii NCMIB 8052,在多种糖源下进行发酵培养,通过比较其在不同糖源条件下的生长情况、糖利用率、丁醇及副产物产量、对丁醇、木糖耐受能力等,综合筛选出了最适用于发酵生产丁醇的备选菌种。NCMIB8052因具有最高产量、相对优良的耐受性及可利用多种糖源的特点,而被确定为发酵能力最强的菌种。 相似文献
997.
目的利用大剂量顺铂(Cisplatin,DDP)诱发小鼠急性肾功能衰竭的动物模型,了解大剂量DDP在引起肾损伤的同时对小鼠肝的毒性作用,探讨髓过氧化物酶(Peroxidase,MPO)与DDP所致小鼠肝功能变化的关系。方法 C57BL/6小鼠50只,雌雄各半,依体重随机分为DDP用药组和生理盐水(NS)对照组。15 mg/kg DDP单次腹腔内注射,等量NS对照。分别取对照组小鼠和DDP用药后6、12、24和48 h小鼠各10只,称重后乙醚麻醉,内眦静脉取血检测肝、肾功能;剖腹取肝、称重、计算肝系数,并取少量肝组织行HE染色、形态学观察;检测血浆和肝组织匀浆中MPO活性,统计学分析。结果大剂量DDP用药后48 h,小鼠出现急性肾功能衰竭。DDP用药后6 h血清谷丙转氨酶(ALT)含量达(91.0±11.3)IU/L,与对照组比较差异有统计学意义(P〈0.05),随后血清ALT含量持续维持在高水平。DDP用药后各组小鼠肝系数明显升高,光镜下见肝细胞广泛变性水肿,肝小叶中可见点状坏死及炎细胞浸润。DDP用药后6 h,小鼠肝组织匀浆MPO含量显著升高,达(1.54±0.45)U/g,与对照组(0.58±0.28)U/g差异有统计学意义(P〈0.01),随后MPO含量降至正常水平;DDP用药后小鼠外周血MPO含量缓慢增高,用药后48 h达(12.78±2.78)U/L,与对照组(8.06±1.89)U/L比较差异有统计学意义(P〈0.05)。结论大剂量DDP在诱发小鼠急性肾功能衰竭的同时还可引起小鼠急性肝细胞的破坏,其发生可能与肝组织内白细胞的激活及MPO的释放有关。 相似文献
998.
Bactericidal activity of grass carp (Ctenopharyngodon idella) serum was significantly enhanced when pre-treated with 15 mg l?1 or 3 mg l?1 of berberine hydrochloride, an effective component of several commonly used herbal medicines in aquaculture. The complement consumption experiment demonstrated that berberine hydrochloride can certainly activate fish complement system. The results of both experiments suggested that berberine hydrochloride could enhance the serum bactericidal activity in grass carp by activating the complement system and indicating the potential in the prevention or treatment of fish diseases. 相似文献
999.
1000.