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Isolation and Identification of Pathogens Causing Marigold (Tagetes erecta L.) Black Spot in Beijing,China 下载免费PDF全文
Dong‐liang Chen Xi Cheng Chang Luo Ming‐yuan Li Qian‐qian Feng Ji‐ye Yan Cong‐lin Huang 《Journal of Phytopathology》2016,164(7-8):547-553
Black spot leads to great marigold losses worldwide. The disease is characterized by black spots on leaves and stems in its early stages, and the whole plant has black rot at the advanced stage. In this report, 6 of 217 Alternaria strains isolated from lesions of marigold plants in Beijing were randomly selected. The morphological characteristics and a pathogenic tree based on two protein‐coding genes (gpd and alt a 1) indicated that Alternaria tagetica is the causal agent of marigold black spot in Beijing. All six Alternaria strains could successfully re‐infect marigold, but they could not infect carrot or zinnia by either spore spray in a greenhouse or planting experiments in the epidemic area. This is the first report of the A. tagetica pathogen being isolated from marigold in Beijing. 相似文献
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Dong Xia Bing Liu Wenyu Xin Tongshen Liu Junyan Sun Nana Liu Song Qin Zhenning Du 《Journal of applied phycology》2016,28(2):765-772
Excessive and long-term alcohol consumption leads to liver disease and low immunity. Extensive evidence suggests that C-phycocyanin (C-PC), a chromophore phycocyanobilin derived from Arthrospira (Spirulina) platensis, exerts protective effects against chemical-induced organ damage and improves immunity. In this study, we investigated whether C-PC could protect against ethanol-induced subacute liver injury and improve immunity. KM mice with ethanol-induced liver injury were established, and animals were divided into three groups that were treated with high, medium, and low doses of C-PC. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), total cholesterol (CHOL), low-density lipoprotein (LDL), total bilirubin (TBIL), liver homogenate malondialdehyde (MDA), and superoxide dismutase (SOD) levels were measured. In addition, the number of thymus T cell subsets was assessed, and liver sections were examined pathologically. C-PC exhibited obvious inhibitory effects on serum ALT, AST, TG, CHOL, LDL, and MDA levels and increased SOD content significantly in the liver. C-PC also increased serum CD3+ and CD4+ cell activation and T cell proliferation significantly compared with the model group. The structure of the hepatic lobules was clear, the liver sinus returned to normal, and the liver cell cords were arranged in neat rows. Therefore, C-PC could protect against ethanol-induced subacute liver injury significantly. 相似文献
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为研究外阴阴道假丝酵母菌病(Vulvovaginal Candidiasis,VVC)患者合并支原体和衣原体感染情况,对86例复发性VVC(recurrent Vulvovaginal Candidiasis,RVVC)患者、219例单纯性VVC患者以及健康妇女200例,分别进行解脲脲原体(Ureaplasma urealyticum,Uu)、人型支原体(mycoplasma hominis,Mh)和沙眼衣原体(Chlamydia trachomatis,CT)检测;所有VVC病例均进行真菌培养。RVVC组和单纯VVC组与对照组之间Uu、Mh及Uu混合Mh阳性率比较,差异均有统计学意义(P0.05)。而三组之间CT和CT混合支原体阳性率比较,均无显著性差异(P0.05)。真菌培养阳性组与阴性组之间,Uu阳性率比较有显著性差异(P0.05),而CT阳性率比较无显著性差异(P0.05)。结果表明,VVC患者合并Uu感染较正常人群明显增高,假丝酵母菌与Uu混合感染可能导致VVC的发生和复发。 相似文献
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