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81.
Jin Ju Lee Jae Hong Kim Dae Geun Kim Dong Hyeok Kim Hannah Leah Simborio Won Gi Min Man Hee Rhee Jong Hwan Lim Hong Hee Chang Suk Kim 《Veterinary microbiology》2014
The pathogenic mechanisms of Brucellosis used to adapt to the harsh intracellular environment of the host cell are not fully understood. The present study investigated the in vitro and in vivo characteristics of B. abortus betaine aldehyde dehydrogenase (BetB) (Gene Bank ID: 006932) using a betB deletion mutant constructed from virulent B. abortus 544. In test under stress conditions, including osmotic- and acid stress-resistance, the betB mutant had a lower osmotic-resistance than B. abortus wild-type. In addition, the betB mutant showed higher internalization rates compared to the wild-type strain; however, it also displayed replication failures in HeLa cells and RAW 264.7 macrophages. During internalization, compared to the wild-type strain, the betB mutant was more adherent to the host surface and showed enhanced phosphorylation of protein kinases, two processes that promote phagocytic activity, in host cells. During intracellular trafficking, colocalization of B. abortus-containing phagosomes with LAMP-1 was elevated in betB mutant-infected cells compared to the wild-type cells. In mice, the betB mutant was predominantly cleared from spleens compared to the wild-type strain after 2 weeks post-infection, and the vaccination test with the live betB mutant showed effective protection against challenge infection with the virulent wild-type strain. These findings suggested that the B. abortus betB gene substantially affects the phagocytic pathway in human phagocytes and in host cells in mice. Furthermore, this study highlights the potential use of the B. abortus betB mutant as a live vaccine for the control of brucellosis. 相似文献
82.
I Rodríguez‐Lozano A Ávalos‐Rodríguez H Castillo‐Juárez F Borderas‐Tordesillas JJ Roa‐Vidal AM Rosales‐Torres 《Reproduction in domestic animals》2014,49(1):27-31
In the spermatozoa of some species, the ubiquitin–proteasome system detects altered proteins and tags them for elimination by the proteasome. In some species' ejaculates, a high proportion of ubiquitinated spermatozoa (i.e. those having ubiquitin bound to the altered or damaged membrane proteins) has been related to infertility. The aim of this study was to assess whether the percentage of ubiquitinated spermatozoa relates to fertility of dairy bulls and whether ubiquitination increases during protein remodelling that occurs during in vitro spermatic capacitation. Thirty‐two frozen semen straws from four high‐fertility (ReproMax®) and four normal‐fertility (Normal) Holstein‐Friesian sires were evaluated. Ubiquitinated and capacitated spermatozoa were quantified by sperm ubiquitin tag immunoassay and chlortetracycline stain, respectively. Fertilizing capacity of sires was assessed by in vitro fertilization. No differences were found between Normal and ReproMax® sires with regard to the observed percentage of ubiquitinated spermatozoa (42.97 ± 3.69% and 49.68 ± 9.27%, respectively; p > 0.05). Additionally, no differences were found in the percentage of ubiquitinated spermatozoa as a consequence of spermatic capacitation in either Normal (42.97 ± 3.69% before capacitation vs 44.67 ± 7.5% after; p > 0.05) or ReproMax® sires (49.68 ± 9.27% before vs 45.05 ± 7.51% after; p > 0.05). The percentage of ubiquitinated spermatozoa in a thawed sperm samples did not correlate with its in vitro fertilizing capacity; thus, this assay does not prove useful to detect in vivo fertility differences between sires. Additionally, protein degradation occurring during remodelling of the spermatozoon plasma membrane during the capacitation process does not seem to involve the ubiquitin–proteasome system. 相似文献
83.
2013年5月22日,南通博物苑鸟类调查组在南黄海边的如东洋口发现一处黑嘴鸥(Larzus saundersi)繁殖地。该繁殖地位于如东大、小洋口之间新围垦的海堤内侧(E121°06’,N32°28’),面积约10000m2。黑嘴鸥营巢于碱蓬(Suaeda gauca)地上,与普通燕鸥(Sternahirundo)、白额燕鸥(Sternaalbifrons)、红脚鹬(Tringatotanus)、环颈鹆(Charadriusalexandrinus)等混群营巢。采用直接计数法统计繁殖区内所见黑嘴鸥的数量在500只以上。应迅速建立保护区以切实保护好这一濒危鸟类及其新繁殖地。 相似文献
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86.
柘林湾网箱养殖海域溶解氧分布及其影响因素 总被引:5,自引:0,他引:5
根据1998年7月在南海东北部柘林湾的调查数据,探讨网箱养殖海域溶解氧的分布及其与其他环境因子间的关系,结果显示夏季海水溶解氧浓度为3.03-7.86mg/L( 平均5.30),退潮时(平均5.71)高于涨潮时(平均4.65)涨潮时网箱区内贫氧( <0.mg/L).多元逐步回归分析表明,对溶解氧浓度有重要影响的水质因子为pH和水温,其次为盐度,COD和营养盐,它们的变化与DO的变化有较好的相关性,区域比较表明,海水溶解氧浓度与观测僧置到网箱区的距离呈正相关(P<0.02),与底质硫物,PO4-P含量呈负相关(P<0.05),溶解氧浓度偏低与养殖环境的污染有直接关系。 相似文献
87.
近年来,河蟹池塘养殖已积累了一些成熟的经验,但从目前河蟹池塘养殖技术水平来看,还存在一些问题。譬如,河蟹商品规格偏小;池塘的空间、水体及饵料资源未充分利用;病虫害防治方法不当;成活率不高等等。因此,需要我们水产工作者进一步去研究、探索。为使主养河蟹池塘获得优质高产高效,并促进池塘河蟹养殖业的可持续发展,我们于1999~2000年进行了《主养河蟹池塘套混养名优品种技术试验》,取得了显著的经济效益和社会效益。现将2000年的试验情况报告如下: 一、试验条件 1.试验地点位于上虞市96丘围涂地区,199… 相似文献
88.
89.
生物有机肥对花生生长发育及产量的影响 总被引:2,自引:0,他引:2
施用生物肥可使花生植株矮壮,分枝增多,防止徒长,提高产量,改善品质,突出表现在荚果和籽粒增大,出米率提高,还可防治花生病害,克服重茬障碍和减轻地下害虫蛴螬的为害。 相似文献
90.
砂壤质潮土夏玉米适宜的化肥种类研究 总被引:3,自引:1,他引:2
采用田间试验研究Agro Services International Inc(ASI)推荐施肥、缓/控释肥、保水型复混肥和普通复混肥对夏玉米产量、SPAD值及养分吸收积累的影响。结果表明,夏玉米施用缓/控释肥和ASI推荐施肥增产效果较好,分别比农户习惯施肥处理增产11.0%和9.8%,保水型复混肥没有显著增产效果。夏玉米专用缓/控释肥养分缓慢释放可弥补砂壤质潮土保肥性差的缺点,能维持夏玉米各生育时期较高的叶片叶绿素含量,促进夏玉米对氮、磷、钾养分的吸收利用,提高干物质积累量,具有显著增产效果,是砂壤质潮土区夏玉米适宜的化肥品种。 相似文献