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为获得能够修复除草剂莠去津污染土壤的高效降解菌,采用摇瓶富集法、平板分离法从莠去津过量使用的土壤中分离得到降解菌SFAD3,通过形态学、生理生化特征观察以及16S rDNA和ITS序列分析进行种类鉴定,测定获得菌株的最适降解条件,并通过土壤接种和盆栽试验验证菌株对莠去津污染土壤的修复作用。结果表明,菌株SFAD3最终被鉴定为门多萨假单胞菌Pseudomonas mendocina,该菌株培养30 d时对污染土壤中50 mg/kg莠去津的降解率可达72.6%;菌株SFAD3在MM液体培养基中最适降解条件为温度37℃、pH 7、莠去津初始浓度6.25 mg/L、接种量2%,对莠去津降的降解率为50.0%~72.2%;与仅有莠去津的处理相比,添加有SFAD3发酵液的处理20 d后芝麻的株高、根长、湿重和干重能够显著恢复,并且该菌对芝麻还具有一定的促生作用。表明降解菌SFAD3在修复莠去津污染土壤方面具有潜在的应用价值。 相似文献
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Expression of Mitochondria‐Associated Genes (PPARGC1A,NRF‐1, BCL‐2 and BAX) in Follicular Development and Atresia of Goat Ovaries 下载免费PDF全文
G Zhang Y Wan Y Zhang S Lan R Jia Z Wang Y Fan F Wang 《Reproduction in domestic animals》2015,50(3):465-473
Most follicles undergo atresia during the developmental process. Follicular atresia is predominantly regulated by apoptosis of granulosa cells, but the mechanism underlying apoptosis via the mitochondria‐dependent apoptotic pathway is unclear. We aimed to investigate whether the mitochondria‐associated genes peroxisome proliferator‐activated receptor‐gamma, coactivator1‐alpha (PPARGC1A), nuclear respiratory factor‐1 (NRF‐1), B‐cell CLL/lymphoma 2 (BCL‐2) and BCL2‐associated X protein (BAX) played a role in follicular atresia through this pathway. The four mitochondria‐associated proteins (PGC‐1α, which are encoded by the PPARGC1A gene, NRF‐1, BCL‐2 and BAX) mainly expressed in granulosa cells. The mRNA and protein levels of PPARGC1A/PGC‐1α and NRF‐1 in granulosa cells increased with the follicular development. These results showed that these genes may play a role in the regulation of the follicular development. In addition, compared with healthy follicles, the granulosa cell in atretic follicles had a reduced expression of NRF‐1, increased BAX expression and increased ratio of BAX to BCL‐2 expression. These results suggested that changes of the mitochondria‐associated gene expression patterns in granulosa cells may lead to follicular atresia during goat follicle development. 相似文献
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为研究由悬浮培养的MDCK细胞制备的H9亚型AIV抗原所制备的灭活疫苗的免疫剂量,在生物反应器中悬浮培养MDCK细胞,接种H9亚型禽流感病毒WD98和HN04种毒,收获抗原液,以2种抗原液分别制备2个毒株的单价油佐剂灭活疫苗。每种疫苗均按照0.3、0.2、0.1、0.05mL/只(107.5 EID50/只~105.52 EID50/只)的剂量接种21日龄SPF鸡,免疫接种后3周采血测定AIV的HI抗体,采血后分别用与制苗株同源的H9亚型AIV种毒静脉注射攻毒,测定疫苗保护率。2种疫苗不同剂量免疫接种后21d的AIV HI抗体水平达到3.8log2~5.6log2,对照组鸡AIV HI抗体均为0log2。攻毒试验证实,以105.52 EID50/只~107.5 EID50/只剂量进行免疫接种,免疫鸡只获得了80%以上的保护。按照兽药典H9亚型禽流感疫苗攻毒保护率90%为合格的标准,悬浮培养MDCK细胞制备的H9亚型禽流感疫苗的最小免疫接种剂量为106.82 EID50/只。 相似文献
55.
Background
Exogenous melatonin could induce cashmere growth. However, induced growth of cashmere fleece by melatonin implants cannot be combined with the typical growth, resulting in earlier shedding followed by another cycle of cashmere growth. To address this issue, we examine the effects on the cashmere yield, fibre characteristics, and the growth and reproductive performance of cashmere goats of planned administration of melatonin.Methods
Eighteen half-sib, female goats were assigned to two treatments (n = 9) including a control and a treatment where melatonin (2 mg/kg BW) was implanted at the end of April and end of June. Cashmere growth and shedding were observed for approximately 1 year following implantation. Fibre samples were collected monthly to determine cumulative cashmere length. Initiation and cessation dates for cashmere growth as well as the rate of cashmere growth were calculated. Cashmere yield, weight gain of dam, kidding date, litter size, and birth weight were also recorded.Results
Melatonin implantation increased cashmere yield by 34.5 % (control 553.7 g vs. melatonin 745.0 g; P < 0.01), cashmere length by 21.3 % (control 95.2 mm vs. melatonin 115.4 mm; P < 0.01), and decreased fibre diameter by 4.4 % (control 14.6 μm vs. melatonin 14.0 μm; P < 0.03). In melatonin-treated goats, the average initiation date was earlier than in control goats (May 18, 2013 vs. July 2, 2013; P < 0.01) but there was a similar cessation date (March 22, 2014 vs. March 27, 2014). Consequently, the duration of cashmere growth was longer in melatonin-treated goats than in control goats (307 vs.270 days; P < 0.01). The final BW, average daily gain, kidding date, litter size, and birth weight were not influenced by melatonin implantation.Conclusions
These data indicate that melatonin implantation (2 mg/kg BW) on two occasions (late April and June) increased cashmere yield by combining the induced growth of cashmere fleece with the typical growth and decreased the fibre diameter without changing dam growth rate or reproductive performance. 相似文献56.
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山区土地资源优化配置的主体核心是确定各种农作物、林果、牧草资源的占地比例及规模。装水镇土地资源优化配置利用方向,在于建设发展以板栗、苹果为主的林果生产基地,畜牧养殖业在于发展以消耗饲草为主的大牲畜(主要是牛)和山羊,另外,种植在5级地上的粮食作物,应以旱作为主。 相似文献
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