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991.
Shujun Ma Qunying Mao Zhenglun Liang Cuijuan Zhang Wenxing Yang Zhe Sun Haijiang Zhang Xinliang Shen Shengli Bi Le Sun 《Cytotechnology》2014,66(3):413-418
Since 2008, enterovirus 71 (EV71) has been responsible for high-mortality seasonal epidemics of hand, foot and mouth disease in China. Currently many groups in the world are in the process of developing EV71 vaccines to combat this deadly disease. We have developed three EV71-specific monoclonal antibodies, and in this study we report the establishment of a fast and cost-effective sandwich ELISA kit for measurement of virus concentration in EV71 vaccines using a pair of mouse anti-EV71 monoclonal antibodies. The system is specific for EV71 virus, with no cross-reactivity to coxsackievirus A16, H1N1, rabies, and hepatitis A. Using a reference EV71 vaccine standard, the sensitivity of the assay kit was determined to be 0.82 U/ml, with a linear range between 3.75 and 120 U/ml. 相似文献
992.
Hon Hing Ho Yuan Ying Su Zi Chao Mao Peng Fei He Yue Qiu He 《Journal of Phytopathology》2014,162(4):272-275
Anthracnose disease was detected from dragon fruit (Hylocereus undatus) at a market of Yuanjiang County, Yunnan Province, China. The results of pathogenicity test, morphology studies and sequence analyses based on ITS and β‐tubulin loci indicated that the disease was caused by Colletotrichum truncatum. The pathogen produced elliptic, yellow spots with chlorotic halos on the surface of the fruit, and the lesion become depressed gradually. Grey to black acervuli appeared on the lesion surface in concentric circles later. This is the first report of dragon fruit anthracnose caused by this pathogen in China. 相似文献
993.
Nan Liu Xiangzhao Mao Meng Yang Bozhong Mu Dongzhi Wei 《World journal of microbiology & biotechnology》2014,30(6):1691-1698
agWH50C, a novel β-agarase gene, was cloned from Agarivorans gilvus WH0801 by degenerate PCR and nested PCR. The gene agWH50C comprized a 2,223-bp, encoding a protein of 740 amino acids. Sequencing results demonstrated that AgWH50C shared 45 % sequence identity with a well characterized β-agarase, Aga50D, from Saccharophagus degradans 2–40. The mature agarase was expressed in Escherichia coli and purified by affinity chromatography. The optimum pH and temperature for AgWH50C activity were 6.0 and 30 °C. The K m and V max values for agarose were 12.55 mg/ml and 1.17 U/mg. Analysis of the hydrolysis products using linear ion trap mass spectrometry, Fourier transform-nuclear magnetic resonance spectrometry and thin-layer chromatography confirmed that the reaction product of AgWH50c was α-neoagarobiose alone. Therefore, our novel agarase has the potential for industrial applications to produce neoagarobiose as well as provides a key β-agarase for fermentation of agar biomass. 相似文献
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995.
Xiao-Xing Xiong Li-Juan Gu Jian Shen Xian-Hui Kang Yue-Ying Zheng Si-biao Yue Sheng-Mei Zhu 《Neurochemical research》2014,39(1):216-224
Stroke results in inflammation, brain edema, and neuronal death. However, effective neuroprotectants are not available. Recent studies have shown that high mobility group box-1 (HMGB1), a proinflammatory cytokine, contributes to ischemic brain injury. Aquaporin 4 (AQP4), a water channel protein, is considered to play a pivotal role in ischemia-induced brain edema. More recently, studies have shown that pannexin 1 channels are involved in cerebral ischemic injury and the cellular inflammatory response. Here, we examined whether the pannexin 1 channel inhibitor probenecid could reduce focal ischemic brain injury by inhibiting cerebral inflammation and edema. Transient focal ischemia was induced in C57BL/6J mice by middle cerebral artery occlusion (MCAO) for 1 h. Infarct volume, neurological score and cerebral water content were evaluated 48 h after MCAO. Immunostaining, western blot analysis and ELISA were used to assess the effects of probenecid on the cellular inflammatory response, HMGB1 release and AQP4 expression. Administration of probenecid reduced infarct size, decreased cerebral water content, inhibited neuronal death, and reduced inflammation in the brain 48 h after stroke. In addition, HMGB1 release from neurons was significantly diminished and serum HMGB1 levels were substantially reduced following probenecid treatment. Moreover, AQP4 protein expression was downregulated in the cortical penumbra following post-stroke treatment with probenecid. These results suggest that probenecid, a powerful pannexin 1 channel inhibitor, protects against ischemic brain injury by inhibiting cerebral inflammation and edema. 相似文献
996.
Xuesong Zhou Jie Jing Jing Peng Wen Mao Yizhou Zheng Du Wang Xin Wang Zhiming Liu Xiangming Zhang 《Gene》2014
Galectin-3 is a multifunctional β-galactoside-binding protein which has been shown to play a role in carcinogenesis. However, the involvement of galectin-3 in osteosarcoma remains unclear. In this study, we aimed to examine the serum level of galectin-3 in osteosarcoma patients and healthy controls, and the protein expression of galectin-3 in osteosarcoma tissues and their adjacent non-malignant tissues. We further aimed to investigate the clinical significance of galectin-3 serum and protein expression levels. Galectin-3 serum level was evaluated using ELISA in 132 osteosarcoma patients and 184 healthy controls, while the protein expression of galectin-3 was determined using immunohistochemistry in the malignant and the surrounding non-malignant tissues of the same 132 osteosarcoma patients. Our results showed that the mean galectin-3 serum level was significantly higher in patients than in controls (2.35 ± 0.91 ng/ml vs. 0.86 ± 0.20 ng/ml) (p < 0.0001). Among patients, a higher galectin-3 serum level was significantly associated with the Enneking stage of cancer (p < 0.0001). In addition, we found a significant overrepresentation of high galectin-3 expression in osteosarcoma tissues than in non-malignant tissues (p < 0.0001). Galectin-3 expression in osteosarcoma tissues was also found to be correlated with the Enneking stage of cancer (p < 0.0001) and the occurrence of metastasis (p < 0.0001). In conclusion, galectin-3 could serve as a useful prognostic marker in osteosarcoma. 相似文献
997.
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999.
二代玉米螟为害玉米产量损失研究 总被引:1,自引:0,他引:1
【目的】研究二代亚洲玉米螟Ostrinia furnacalis(Guenee)为害对玉米产量的影响。【方法】以"先玉335"为供试玉米品种,通过人工接虫模拟二代玉米螟不同发生量为害玉米对产量损失的影响。【结果】随着接卵量增加,虫孔数和蛀孔隧道长度增加,玉米单穗粒重降低。单株虫孔数每增加1个,玉米产量损失率增加4.52%;隧道长度每增加10 cm,产量损失率增加8.34%。接卵量与玉米产量损失率的关系符合方程z=-10.0297+4.034 ln(x)。【结论】根据害虫经济阈值的定义,推算出二代玉米螟的防治指标为百株累积卵量12.8块,对二代玉米螟的防治决策具有重要指导作用。 相似文献
1000.
Guihua Lu Xiping Wang Junhua Liu Kun Yu Yang Gao Haiyan Liu Changgui Wang Wei Wang Guokui Wang Min Liu Guanfan Mao Binfeng Li Jianying Qin Mian Xia Junli Zhou Jingmei Liu Shuqin Jiang Hua Mo Jinteng Cui Nobuhiro Nagasawa Shoba Sivasankar Marc C. Albertsen Hajime Sakai Barbara J. Mazur Michael W. Lassner Richard M. Broglie 《Plant cell reports》2014,33(4):617-631