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1.
The present study was designed to investigate the potential application of native (N) and recombinant (truncated modified [tmFliC] and full-length [flFliC]) flagellin proteins along with inactivated Newcastle disease virus (NDV). Fifty six SPF chickens were immunized twice with PBS (control), inactivated NDV (Ag), inactivated NDV/flFliC (AgF), inactivated NDV/tmFliC (AgT), inactivated NDV/N (AgN), commercial vaccine containing Montanide (Vac) and Vac/N (VacN), with a two-week interval. Blood was collected weekly and spleens were harvested after chickens were sacrificed. Interleukin-6 (IL-6) and tumor necrotic factor-α (TNF-α) gene expression in peripheral blood mononuclear cells were analyzed by Real-Time PCR. Antibody response was assessed by haemagglutination inhibition (HI). Cellular activity was quantified by MTT assay. Results showed that the most IL-6 and TNF-α gene expression was observed in AgF group (P < 0.01). The lowest gene expression among vaccinated groups was observed in Ag group for IL-6 and Ag and Vac group for TNF-α. The highest HI titer was observed in Vac, VacN, AgF and AgT groups. The AgF group showed the highest cellular activity (P < 0.01). In conclusion, flagellin-adjuvanted groups showed a pro-inflammatory effect and acted similarly to or better than the Vac group. Hence, flagellin can be proposed as a potential adjuvant for ND vaccine.  相似文献   
2.
黄瓜在我国蔬菜产业中占有重要地位,然而连片种植、重茬栽培等条件下容易滋生病菌,尤其是随着我国保护地蔬菜生产规模的扩大,棚室内的温湿度条件更利于病害的发生与流行,黄瓜生产上面临着严重的病虫害威胁,包括生理性病害、感染性病害及虫害等。本文从抗病品种选育的角度分析了黄瓜病害抗病品种选育技术,并简要介绍了其他防治方法,展望了相关研究的发展方向,为黄瓜病虫害的防治提供参考。  相似文献   
3.
CAO Rui-ping  WANG Jiao  WANG Ce 《园艺学报》2018,34(6):1061-1066
AIM: To investigate the role of zerumbone (ZER) in 1-methyl-4-phenylpyridinium (MPP+)-induced cytotoxicity of human neuroblastoma SH-SY5Y cells. METHODS: Human neuroblastoma SH-SY5Y cells were cultured in vitro and the protective effect of ZER against MPP+-induced cytotoxicity was measured by CCK-8 assay. Flow cytometry was used to determine the apoptosis and reactive oxygen species (ROS). The expression of Parkinson disease protein 7 (PARK7) was knocked-down by using PARK7-specific short hairpin RNA (shRNA). The protein levels of PARK7, nuclear factor E2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) were determined by Western blot. RESULTS: MMP+ remarkably reduced the cell viability in a dose-dependent and time-dependent manner. The SH-SY5Y cell injury model was established by treatment with MPP+ at 600 μmol/L for 24 h. ZER up-regulated the protein levels of PARK7 and Nrf2 (P<0.05), alleviated apoptosis (P<0.05), and reduced ROS production (P<0.05) in the SH-SY5Y cell injury model. Meanwhile, N-acetyl-L-cysteine (NAC) had the similar functions. Moreover, significant reductions in the protein levels of Nrf2 and HO-1 (P<0.05), and obvious increases in apoptosis (P<0.05) and ROS level (P<0.05) were demonstrated in PARK7-knockdown cells. CONCLUSION: ZER protects SH-SY5Y cells against MPP+-induced cytotoxi-city, which may be related to activation of PARK7/Nrf2/HO-1 pathway, and subsequent attenuation of oxidative stress and apoptosis.  相似文献   
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5.
陈彩娣 《蔬菜》2019,(10):51-53
黄瓜病虫害种类多、危害大,传统用药方式严重影响产品质量和口感。为了保证直供上海的黄瓜达到无公害要求,对生产基地采取农业防治、生态控制、生物防治和物理防治相结合的绿色防控措施,化学农药使用量减少30%,综合防治效果在85%以上,有效减少了防治次数,降低了农产品的农药残留,667 m~2增产600 kg,增值600元左右。收到了较好的经济、生态及社会效益。  相似文献   
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7.
采用大田裂区试验,研究了施用锌肥和不同遮阴程度互作对花生生长发育、抗病性及产量的影响。结果表明,与不施锌肥相比,施用锌肥能提高花生不同部位锌含量、增加叶片SPAD值,提高花生叶片中可溶性糖、蛋白质和生长素含量,减少花生病害的发生,平均降低7.1个百分点,花生产量平均增加19.4%。相同施锌水平下,随着遮阴程度的增加,花生不同部位锌的含量和不同生育期叶片SPAD值以及花生叶片中可溶性糖、蛋白质和生长素含量呈增加趋势,花生的发病率比不遮阴对照增加4.8、10.2个百分点,花生产量平均降低16.5%、10.0%。在30%、70%的遮阴条件下,施用锌肥的花生产量比不施锌的分别提高21.1%、25.0%。本试验条件下,施用七水硫酸锌30 kg/hm2,使花生具有较强的抗低温寡照能力及抗病性能,增产显著,可在花生产区推广应用。  相似文献   
8.
捕食线虫性真菌的分离培养及分布规律   总被引:6,自引:1,他引:5  
对自然界中的捕食线虫性真菌进行了分离和种属区分,并对分布规律进行了研究。从土壤、粪便等材料中获得了2类活性较强的捕食线虫性菌株:即套捕型(hooping)捕食线虫性真菌和粘捕型(sticking)捕食线虫性真菌。主要的代表种类有3种。这些捕食线虫性真菌在捕食性结构分生孢子形态及某些生物学特性上有一定差异。套捕型捕食线虫性真菌代表种为少孢节丛孢菌(Arthrobotrys oligospara)和梨形指环菌(Dactylaria pyriformis),它们以菌环、菌网作为捕食性结构(器官),以套捕方式杀灭线虫幼虫。梨形指环菌可产生多量厚垣孢子(chlamyalospore)。粘捕型捕食线虫性真菌代表种为纺锤隔指孢菌(Dactylella ellipsospora)。可形成菌结捕食线虫性结构,以粘捕的方式杀灭线虫幼虫。结果表明:捕食线虫性真菌在土壤和家畜粪便中的分离率是40.41%;此类菌适合于生存在阴暗、潮湿、富含腐植质的环境中。在温暖季节时,采用0.4g/L玉米粉琼脂培养基(CMA)易于对其进行分离培养。  相似文献   
9.
A disease causing the decline of papaya (Carica papaya) plants was noticed in the Jordan Valley in 1982. The disease caused severe yellowing of the upper leaves and dieback of the apex. The disease was not transmissible mechanically and continued efforts to associate viruses and viroids have so far been unsuccessful. Epidemiological observations suggested that the disease is airborne and probably caused by a mollicute. In order to test this hypothesis, plots were covered by an insect-proof net and with white nets providing 15, 30 and 50% shade. The 30%, 50% and insect-proof nettings provided complete protection, and the 15% netting reduced disease incidence to <2%, compared with>37% in the uncovered control plot. Spraying plants at weekly intervals with a commercial whitewash solution was also found to be effective in reducing disease incidence. The advantages of using a range of netting field treatments as a simple means for obtaining information on the epidemiological nature of a new disease are described.  相似文献   
10.
本试验对捕食线虫性真菌菌种保存技术进行了研究,测定了在不同介质保存条件下,捕食线虫真菌分生孢子和菌丝的存活情况及其不是寄生性线虫的能力.结果表明:在设定的保存条件下,分别经过1周冷冻融化或2周反复冷冻融化,被保存的分生孢子接种于玉米粉琼脂培养基上能生长发育:在加入线虫第3期幼虫后,能生产捕食器,对虫体发挥捕食作用.  相似文献   
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