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951.
为了研究拮抗细菌Enterobacter cloacae B8在野外水稻叶面上的定殖情况及拮抗作用,由自然选择和Tn5诱变从B8产生了一株抗菌素抗性突变体BX8.BX8能在含利福平达400μg/ml或卡那霉素达300μg/ml的LB培养基中生长.实验表明该抗菌素抗性的产生没有降低BX8的拮抗活性.该抗性比较稳定,在无抗菌素培养基中培养.BX8至少分裂生长60代内抗性不变. 相似文献
952.
利用美国Landsat-5夏末时相的TM-CCT数据,经计算机处理,外拍成像的TM图像,采用简化的目视综合解译法,专题解译稻田信息,其结果的定性解译正确率为93.9%,宏观面积精度为99.5%,从而明确了只要有合适的TM资料,那么,对平原稻区的县级以上的水稻遥感估产稻田面积进行监测是可能的。 相似文献
953.
Because of cloudy and rainy weather in south China, optical remote sens-ing images often can't be obtained easily. With the regional trial results in Baoying, Jiangsu province, this paper explored the fusion model and effect of ENVISAT/SAR and HJ-1A satel ite multispectral remote sensing images. Based on the ARSIS strat-egy, using the wavelet transform and the Interaction between the Band Structure Model (IBSM), the research progressed the ENVISAT satel ite SAR and the HJ-1A satel ite CCD images wavelet decomposition, and low/high frequency coefficient re-construction, and obtained the fusion images through the inverse wavelet transform. In the light of low and high-frequency images have different characteristics in differ-ent areas, different fusion rules which can enhance the integration process of self-adaptive were taken, with comparisons with the PCA transformation, IHS transfor-mation and other traditional methods by subjective and the corresponding quantita-tive evaluation. Furthermore, the research extracted the bands and NDVI values around the fusion with GPS samples, analyzed and explained the fusion effect. The results showed that the spectral distortion of wavelet fusion, IHS transform, PCA transform images was 0.101 6, 0.326 1 and 1.277 2, respectively and entropy was 14.701 5, 11.899 3 and 13.229 3, respectively, the wavelet fusion is the highest. The method of wavelet maintained good spectral capability, and visual effects while improved the spatial resolution, the information interpretation effect was much better than other two methods. 相似文献
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956.
目的观察中草药提取物MACC5(为广东医学院肾脏病研究所提取物代号)对SD大鼠抗Thy1.1系膜增生性肾炎实验模型的疗效。方法制备兔抗大鼠胸腺细胞免疫血清(ATS),再将ATS经尾静脉注射给SD大鼠,诱导其发生系膜增生性肾炎(MsPGN)后,随机分为3组,每组5只;试验组分别经腹腔注射MACC51.0mL和3.0mL,对照组注射生理盐水(NS)1.0mL;每日观察其尿量、尿蛋白定量,并于第11天处死各大鼠,取肾组织切片观察系膜增殖程度,并用免疫组化法检测肾小球系膜区细胞增殖核抗原(PCNA)的表达。结果两试验组24h尿量均多于对照组(P<0.05);两试验组尿蛋白定量均少于对照组(P<0.01);两试验组单位肾小球系膜细胞(GMC)数均少于对照组(P<0.001);
MACC53.0mL试验组肾小球系膜区PCNA的表达低于对照组(P<0.05)。结论MACC5对大鼠MsPGN实验模型具有利尿、降低尿蛋白和促进肾小球系膜损伤修复的作用。 相似文献
957.
958.
5%调环酸钙泡腾片在水稻生产上的应用试验 总被引:1,自引:0,他引:1
通过田间试验,探索植物生长调节剂5%调环酸钙泡腾片在水稻生产上的应用效果,对水稻关键生育期、株高、节间长度、抗倒伏性以及产量等因素进行分析,结果表明,在水稻拔节前10 d喷施5%调环酸钙泡腾片,能够有效降低株高,缩短基部节间长度,减少倒伏发生面积,增加穗数及千粒重,进而达到增产效果,其适宜剂量12~30 g/667 m2。 相似文献
959.
为了实现对Y-shaped果树的精准喷施,本文融合了彩色及深度视觉图像,提出了1种基于蚁群避障算法的果园最优行驶路径的规划方法。首先,对彩色图像进行图像分割处理,划分道路及果树树墙障碍区域,得出喷施设备的可行驶区域,提出了喷施行驶范围检测算法;然后,通过对深度图像和彩色图像融合的处理,将Y-shaped果树树冠边缘轮廓精准拟合形成栅格地图,并与蚁群避障算法相结合,提出了最优行驶路径规划算法。最后,对拟合曲线和Y-shaped果树树冠边缘轮廓进行检验,验证算法的拟合程度。实验结果证明,本文提出的路径规划算法可以准确地检测出果树区域,并实现对行驶路径的精准规划。 相似文献
960.
LIU Yong-fa HUANG Yu-mei ZHANG Zong-yao WAN Hong WANG Mei LV Jia-min LUO Kai-jian 《中国畜牧兽医》2015,42(8):2176-2182
To investigate the pathogenicity of A/Hero/Guangdong/C1/2013(H5N6), an AIV strain isolated from Heron on ducks and mice, pathogenicity of this new virus strain and changing of histopathology as well as a preliminary study on its biological characteristics were studied by virus challenges test via intranasal and eye-drop and in chicken via jugular vein injection.Results showed that the EID50 of this strain of virus was 10-8.16/0.1 mL in embryonated chicken eggs and the intravenous inoculation of pathogenic index (IVPI) was 2.76.In ducks and mice, the 50% lethal doses (LD50) of it were determined to be 10-4.0/0.2 mL and 10-4.67/0.05 mL, respectively.Symptoms of infection included loss of appetite, depression, swollen head and tears after being infected with 106 EID50 per duck by intranasal and eye-drop administration.Most of ducks died 4 to 7 days post-infection, liver, lung and kidney still eliminated toxicants at day 7 post-infection.Anatomy showed symptoms of pericardial effusion, pulmonary congestion and kidney enlargement, while pathological section showed pathological change like karyopycnosis and inflammatory cell infiltration in heart, liver, kidney and spleen.Mice developed symptoms of infection like loss of appetite, depression, shaggy coat and ruffled coat after being infected with 5×105 EID50 per mouse by intranasal and eye-drop administration.Most of the infected mice died 5 to 7 days post-infection and only liver still eliminated toxicants at day 7 post-infection.Although organ anatomy showed no obvious pathological changes, pathological section showed pathological changes like karyopycnosis and inflammatory cell infiltration in heart, kidney and lung.Our research demonstrated that this H5N6 subtype AIV had a strong pathogenicity and could be defined as a highly pathogenic AIV strain as its IVPI was greater than 1.2.Our work laid a theory foundation for study, prevention and control of H5N6 subtype AIV. 相似文献