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31.
采用 4 0英尺集装箱熏蒸处理纸箱 ,实验对箱中溴甲烷气体分布及散气后溴甲烷残留进行了检测研究。结果表明 ,温度高低、集装箱中纸箱堆放和电扇鼓风等情况对溴甲烷分布与扩散影响明显。集装箱装满纸箱情况下 ,当温度≥ 2 1℃ ,投药 2h后上、下检测点平均溴甲烷浓度达到最低浓度要求 ;当温度 <2 1℃时 ,投药 2 4h后上检测点平均溴甲烷浓度仍达不到最低浓度要求。当集装箱中间留有通道或使用电扇鼓风情况下 ,投药 2h后各检测点溴甲烷浓度分布达到最低浓度要求。集装箱装满纸箱情况下 ,溴甲烷向大气扩散较慢 ,即使电扇鼓风散气2h ,2 4h后溴甲烷残留量仍达不到安全指标要求。集装箱中间留有通道情况下 ,箱中溴甲烷残留量下降很快 ,并可达到安全指标要求。 相似文献
32.
夏大豆成熟期害鼠防治指标的研究潘学锋(安徽省霍邱县植保站237400)刘同群(霍邱县城西湖乡农技站)摘要本文通过大田调查夏大豆田的害鼠发生种类及其密度与产量损失的关系,结果表明,沿淮地区夏大豆田的害鼠种类为黑线姬鼠、黑线仓鼠、褐家鼠、小家鼠等,其中以... 相似文献
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油菜菌核病菌对多菌灵和乙霉威的抗药性机理 总被引:1,自引:0,他引:1
生物测定结果表明,油菜菌核病菌田间菌株对多菌灵(MBC)敏感性表型呈多样性,即存在MBCS、MBCLRLR、MBCHRHR和MBCVHR表型.而对乙霉威(DIE)则只检测到DIES和DIEHR表型.MBCS、MBCLR和MBCHR菌株中除JD2-3菌株为DIES外,其余菌株均为DIEHR,MBCVHR菌株对DIE表现为DIES.MBC和DIE之间存在典型的负相关交互抗性.序列分析结果表明,表型为MBCVHRDIES菌株的β-微管蛋白基因,第198位氨基酸由Glu(GAG)突变为Ala(GCG);表型为MBCHRDIEHR菌株的β-微管蛋白基因的突变位点在第200位,由Phe(TTC)突变为Tyr(TAC);而表型为MBCSDIES和MBCLRDIEHR的菌株在所扩增的β-微管蛋白基因片段中未发生突变.初步表明,β-微管蛋白基因198和200位氨基酸的突变是引起油菜菌核病菌对多菌灵抗药性呈多样性的分子机理. 相似文献
35.
葡萄品种浆果成熟期多样性及归类标准评价 总被引:5,自引:0,他引:5
对郑州葡萄圃内260个鲜食和153个酿酒品种的浆果成熟期进行了鉴定评价。在郑州地区,最早熟的葡萄种质材料早莎巴珍珠6月29日生理成熟,果实发育期48d;最晚熟的种质材料大宝10月12日成熟,果实发育期144d,在其间的103d时间里不断有成熟的葡萄品种,表现了丰富的多样性。酿酒葡萄的果实成熟期相对集中,大多数酿酒葡萄品种在8月中旬成熟,7月份和9月份成熟的葡萄品种所占的比例极少。果实发育期≤60d、61~80d、81~100d、101~120d、≥121d的品种次数呈正态分布,果实发育期81~100d的品种占收集品种的53.03%;果实发育期少于60d的极早熟品种和果实发育期多于120d的极晚熟品种所占比例较少。早、中、晚熟品种按照浆果发育期进行归类较为简便。 相似文献
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湿地松粉蚧三种寄生蜂蛹及蛹壳的比较 总被引:2,自引:0,他引:2
本文主要通过对湿地松粉蚧Oracella acuta(Lobdell)两种引进天敌迪氏跳小Zarhopalus debarri、火炬松短索跳小蜂Acerophagus coccois与本地天敌粉蚧长索跳小蜂Anagyrus dactylopii(Howard)的蛹及蛹壳的比较,指出可通过寄生蜂蛹及蛹壳的形状、颜色、羽化孔、表面结构特征等对上述三种寄生蜂进行区分。 相似文献
38.
WANG Li-wei CHEN Li-xin MAO Jian-wen ZHU Lin-yan NIE Si-huai ZHONG Ping SUN Xue-rong CAI Bo LI Pan 《园艺学报》2004,20(8):1349-1352
AIM: To investigate the relationship between osmolarity, cell volume and cell proliferation in nasopharyngeal carcinoma cells. METHODS: MTT method was applied to detect the proliferation ability of the poorly-differentiated nasopharyngeal carcinoma cell (CNE-2Z) under various osmolarity conditions. The flow cytometry was used to analyse cell cycle distribution. Cell volume was obtained by the image analysis of living cells and cell viability was determined by the trypan blue assay. RESULTS: Cultivation of cells under the hypertonic conditions of 370 and 440 mOsmol/L increased cell volume by 8.7% and 27.8% and facilitated cell proliferation by 22.2% and 33.9%, respectively. However, hypotonic incubation of cells with osmolarity of 160 and 230 mOsmol/L decreased cell volume by 12.8% and 4.1% and inhibited cell proliferation by 34.0% and 15.6%, respectively. Cell volume was positively correlated with cell proliferation rate. Long-term cultivation of cells under anisotonic conditions did not significantly alter cell cycle distribution, but hypotonic cultivation decreased cell viability. CONCLUSION: Proliferation of nasopharyngeal carcinoma cells was closely correlated with the osmolarity of culture medium and cell volume. Hypotonic cultivation may inhibit cell proliferation by decreasing cell volume to facilitate cell death mechanisms. 相似文献
39.
Qiu-yan Chang Fu-cheng Guo Xue-rui Li Jian-hua Zhou Xuepeng Cai Qiuwei Pan Xiao-xia Ma 《Veterinary research communications》2018,42(4):309-313
Peste des petits ruminants virus (PPRV) causes highly contagious diseases in domestic and particular wild small ruminants, leading to substantial economic loss. The development of effective and cheap antiviral medications shall help to circumvent this emerging burden. In this study, we found that ribavirin, a competitive inosine-5’-monophosphate dehydrogenase (IMPDH) inhibitor, significantly inhibits the replication of PPRV. As IMPDH is a key enzyme in purine nucleotide synthesis, supplementation of exogenous guanosine attenuate the anti-PPRV effect of ribavirin. Interestingly, an uncompetitive IMPDH inhibitor, mycophenolic acid (MPA), exerted more potent antiviral effect again PPRV. Similarly, this effect was largely restored upon supplementation of guanosine. Thus, we have demonstrated that the IMPDH inhibitors ribavirin and MPA combat PPRV infection through purine nucleotide depletion. Because both regimens have been widely used in the clinic for treating viral infection or organ rejection in transplantation patients for decades, respectively, repurposing these existing safe and cheap medications may provide a new avenue for combating PPRV infection. 相似文献
40.
Methyl donors dietary supplementation to gestating sows diet improves the growth rate of offspring and is associating with changes in expression and DNA methylation of insulin‐like growth factor‐1 gene 下载免费PDF全文
Yang Zhao Yuedong Xuan Daolin Mou Hong Liu Pan Zhou Zhengfeng Fang Lianqiang Che Shengyu Xu Bin Feng Jian Li Xuemei Jiang Yan Lin De Wu 《Journal of animal physiology and animal nutrition》2018,102(5):1340-1350
The study aimed to investigate the effects of maternal dietary methyl donors on the performance of sows and their offspring, and the associated hepatic insulin‐like growth factor‐1 (IGF‐1) expression of the offspring. A total of 24 multiparous sows were randomly fed the control (CON) or the CON diet supplemented with methyl donors (MD) at 3 g/kg betaine, 15 mg/kg folic acid, 400 mg/kg choline and 150 μg/kg VB12, from mating until delivery. After farrowing, sows were fed a common lactation diet through a 28‐days lactation period and six litters per treatment were selected to be fed until at approximately 110 kg BW. Maternal MD supplementation resulted in greater birthweight (p < 0.05) and increased the piglet weights (p < 0.01) and litter weights (p < 0.05) at the age of day 28, compared with that in CON group. The offspring pigs in the MD group had greater ADG (p < 0.05) and tended to lower F:G ratio (p = 0.07) compared with that of CON group from day 28 to 180 of age. The offspring pigs from MD group had greater serum IGF‐1 concentrations and expressions of hepatic IGF‐1 gene and muscular IGF‐1 receptor (IGF‐1r) protein at birth (p < 0.05), and greater hepatic IGF‐1 protein (p = 0.03) and muscular IGF‐1r gene expressions (p < 0.05) at slaughter, than that from the CON group. Moreover, the methylation at the promoter of IGF‐1 gene in the liver of newborn piglets and finishing pigs was greater in the MD group than that of the CON group (p < 0.05). In conclusion, maternal MD supplementation throughout gestation could enhance the birthweight and postnatal growth rate of offspring, associated with an increased expression of the IGF‐1 gene and IGF‐1r, as well as the altered DNA methylation of IGF‐1 gene promotor. 相似文献