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1.
作者综述了线粒体损伤、钙超载与肉鸡腹水综合征的关系,钙超载可能是肉鸡腹水综合征发生和发展中,心、肺及其血管损伤和功能紊乱的机制,而线粒体损伤可以导致细胞内钙超载,同时钙超载后加重了线粒体的损伤。作者还指出了日粮钙与肉鸡腹水综合征的发生可能有关。  相似文献   
2.
Resistance tests were made on seedlings of transformed lines of Nicotiana benthamiana which contain a transgene encoding the coat protein (CP) gene of a Scottish isolate of potato mop-top virus (PMTV). This transgene has been reported to confer strong resistance to the PMTV isolate from which the transgene sequence was derived and also to a second Scottish isolate. Plants of lines of the transgenic N. benthamiana were as resistant to two Swedish and two Danish PMTV isolates as to a Scottish isolate, and of five lines tested, greater than 93.5% of transgenic plants were immune. The coat protein gene sequences of these four Scandinavian isolates were very similar to those of the two Scottish isolates. The greatest divergence between the isolates was three amino acid changes and there was less than 2% change in CP gene nucleotide sequence. It is concluded that the PMTV CP transgene used in these experiments could confer resistance against isolates from different geographical areas because it is becoming apparent that the CP genes of PMTV isolates are highly conserved.  相似文献   
3.
张帅  曾鑫年  骆悦 《植物保护》2004,30(6):11-14
线粒体复合体Ⅰ呼吸抑制剂不仅在医药上有着重要的研究价值,在农药方面也有着特殊的意义。这类药剂的作用机制比较特殊,害虫不易产生抗性,是一类非常有前途的杀虫药剂。从植物,微生物等生物体中发现了许多线粒体复合体Ⅰ呼吸抑制剂,如鱼藤酮、粉蝶霉素A、辣椒碱,番荔枝内酯、myxalamid等,它们可以作为农药的先导化合物进行药物合成。根据不同的作用方式,线粒体复合体Ⅰ呼吸抑制剂可分3种类型,分别以粉蝶霉素A、鱼藤酮、辣椒碱为代表。  相似文献   
4.
Dwarf Lulu cattle, the only Bos Taurus type of cattle in Nepal, are raised under severe environments in the mountainous zone of that country. In the present study, the body measurement traits, cytogenetic and molecular genetic characteristics of the Lulu cattle are investigated. Blood samples were collected from 31 animals in four villages (altitudes 2590–3550 m) in the southern part of Mustang. The Lulu cattle had a normal karyotype with 2n = 60, XY or XX. Only one male examined had a large submetacentric X‐chromosome and a small submetacentric taurine type Y‐chromosome. The mitochodrial DNA (mtDNA) genotypes were analyzed by PCR mediated restriction fragment length polymorphisms, displacement (D)‐loop region PCR mediated single strand conformation polymorphisms, and D‐loop region sequences. Many base substitutions were found in the D‐loop region, suggesting that the Lulu cattle originated from at least 10 maternal lines. Three types of mtDNA from these cattle were found, the Bos taurus type (n = 23), the Bos indicus type (n = 6), and the Bos grunniens type (n = 2). In the village at the lowest altitude, four of the five cows were of the Bos indicus type. These results indicated that mtDNA types of the Lulu cattle mostly belong to Bos taurus, but have been hybridized with Bos indicus cattle in lower‐elevation regions in their maternal lineage.  相似文献   
5.
Two virus isolates from water samples — one from a small stream in South Western Germany and another one from the Havel river in North Eastern Germany c. 500 km away, proved to be strains, named S and H, respectively, of a new Tombusvirus for which the name Havel river virus (HaRV) had been suggested previously in a brief account. Immunoelectron microscopical decoration tests and sequence comparisons of the coat proteins indicated that the two HaRV strains are only distantly related to known Tombusviruses. The closest relationships were found to Cucumber necrosis virus. Nothing is known about their natural hosts. Because the S strain of HaRV was isolated in a woody area from a small stream close to its origin, they may be pathogens of trees or wild plants in such habitats.  相似文献   
6.
ABSTRACT

1. The objectives of the current study were to investigate the mitochondrial genome and molecular phylogeny of Lueyang black-bone chicken, and provide molecule base to preserve and explore the specific chicken strain.

2. Based on sequencing and clustering, the complete mitochondrial DNA map and sequences of Lueyang black-bone chicken were revealed, and two phylogenetic trees of Lueyang black-bone chickens based on D-loop sequences and the mitochondrial genome were constructed.

3. The results showed that the complete mitochondrial genome of Lueyang black-bone chickens is 16,784bp in size, consisting of 22 transfer RNA genes, two ribosomal RNA genes, 13 protein-coding genes, and one non-coding control region. The base composition of the complete mtDNA sequence is 30.28% for A, 23.78% for T, 32.42% for C, 13.52% for G. Additionally, 10 haplotypes of D-loop sequences in 32 Lueyang black-bone chickens were detected, which were distributed into 4 clades (A, B, C and E).

4. It was concluded that genetic diversity is wide in Lueyang black-bone chickens, and this strain has multiple maternal origins from different regions in China and neighbouring regions.  相似文献   
7.
To investigate the effect of histone deacetylation inhibitor Psammaplin A (PsA) on the development of bovine aging oocytes in vitro,oocytes were randomly divided into control group,aging group and 50 mmol/L PsA treated aging group (PsA group).Immunofluorescence staining and JC-1 were used to detect the blastocyst rate of bovine oocytes after parthenogenetic activation,the number of cells in blastocysts,apoptosis,reactive oxygen species (ROS),glutathione (GSH) and mitochondrial membrane potential intensity of embryos.The results showed that the blastocyst rate of the aging group was significantly lower than that of PsA and control groups (P<0.05).The blastocyst rate of PsA group was not significantly different from that of control group (P>0.05).The number of cells in the blastocysts of control group and PsA group were significantly higher than that of aging group (P<0.05).The number of cells in the blastocysts of PsA group was not significantly different from that of control group (P>0.05).The apoptosis rate in aging group was significantly higher than that of control and PsA groups (P<0.05),the apoptosis rate of PsA group was significantly higher than that of control group (P<0.05).The GSH level of MⅡ oocytes in aging group was significantly lower than that of control and PsA groups (P<0.05).There was no significant difference in GSH level between control and PsA groups (P>0.05).The ROS level of the embryos in aging group was significantly higher than that of control and PsA groups (P<0.05).The ROS level in PsA group was significantly higher than that of control group (P<0.05).The mitochondrial membrane potential of early embryos of aging group 4-8 cells was significantly lower than that of control and PsA groups (P<0.05).The mitochondrial membrane potential intensity of control group was significantly higher than that of PsA group (P<0.05).In summary,PsA could effectively delay the aging of bovine oocytes and improve the quality of oocytes.  相似文献   
8.
线粒体是细胞内重要的细胞器,具有多种功能,是细胞的能量工厂。线粒体含有自己的遗传物质线粒体DNA,线粒体DNA因其在氧化磷酸化中的作用而广为人知。近年来,越来越多的研究表明线粒体DNA可作为先天性免疫系统的激动剂,并在病原体感染和炎性疾病的病理发展中起重要作用。线粒体DNA在进入细胞质或细胞外环境后,可以激活多种先天性免疫系统的模式识别受体,从而触发促炎细胞因子分泌和Ⅰ型干扰素反应。因此,本文就线粒体DNA激活先天性免疫的机制以及其在病原体感染和相关疾病发生发展中的作用进行讨论、总结,以期为进一步深入开展线粒体DNA在病原体感染及相关疾病中的作用及其机制研究提供理论依据。  相似文献   
9.
旨在探究死亡受体Fas在镉致大鼠肾上腺嗜铬细胞瘤细胞(PC12)凋亡中的作用及其对线粒体通路的调控机制,用10 μmol·L-1镉处理Fas基因沉默的PC12细胞株12 h,通过Western blot检测BH3相互作用域死亡激动剂(BID)、半胱氨酸蛋白酶-9(caspase-9)、半胱氨酸蛋白酶-3(caspase-3)、多聚二磷酸腺苷核糖聚合酶(PARP)的活化情况,Bcl-2相关X蛋白(Bax)、B细胞淋巴瘤/白血病-2基因(Bcl-2)、凋亡诱导因子(AIF)、核酸内切酶G(Endo G)的表达情况,以及细胞色素C(Cyt C)在细胞内的分布情况,免疫荧光染色检测AIF核转位。结果显示,镉极显著上调tBID/BID比值和Bax/Bcl-2比值,诱导Cyt C从线粒体释放到细胞质,激活caspase-9、caspase-3和PARP,增加AIF和Endo G蛋白表达水平(P<0.01),并诱导AIF核转位;沉默Fas极显著抑制镉引起的tBID/BID比值和Bax/Bcl-2比值升高,Cyt C从线粒体释放到胞浆,caspase-3、PARP蛋白活化和AIF、Endo G蛋白表达水平极显著升高(P<0.01),显著抑制镉激活的caspase-9(P<0.05),并抑制AIF核转位。综上表明,Fas通过调控线粒体通路参与镉致PC12细胞凋亡。  相似文献   
10.
Myanmar indigenous chickens play important roles in food, entertainment, and farm business for the people of Myanmar. In this study, complete mitochondrial D-loop sequences (1232 bp) were analyzed using 176 chickens, including three indigenous breeds, two fighting cock populations, and three indigenous populations to elucidate genetic diversity and accomplish a phylogenetic analysis of Myanmar indigenous chickens. The average haplotype and nucleotide diversities were 0.948 ± 0.009 and 0.00814 ± 0.00024, respectively, exhibiting high genetic diversity of Myanmar indigenous chickens. Sixty-four haplotypes were classified as seven haplogroups, with the majority being haplogroup F. The breeds and populations except Inbinwa had multiple maternal haplogroups, suggesting that they experienced no recent purifying selection and bottleneck events. All breeds and populations examined shared haplogroup F. When 232 sequences belonging to haplogroup F (79 from Myanmar and 153 deposited sequences from other Asian countries/region) were analyzed together, the highest genetic diversity was observed in Myanmar indigenous chickens. Furthermore, Myanmar indigenous chickens and red junglefowls were observed in the center of the star-like median-joining network of 37 F-haplotypes, suggesting that Myanmar is one of the origins of haplogroup F. These findings revealed the unique genetic characteristic of Myanmar indigenous chickens as important genetic resources.  相似文献   
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