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Lingyu Xu Chenfu Cao Zhiyi Yang Weixin Jia 《Journal of veterinary science (Suw?n-si, Korea)》2022,23(4)
BackgroundASF was first reported in Kenya in 1910 in 1921. In China, ASF spread to 31 provinces including Henan and Jiangsu within six months after it was first reported on August 3, 2018. The epidemic almost affected the whole China, causing direct economic losses of tens of billions of yuan. Cause great loss to our pig industry. As ELISA is cheap and easy to operate, OIE regards it as the preferred serological method for ASF detection. P54 protein has good antigenicity and is an ideal antigen for detection.ObjectiveTo identify a conservative site in the African swine fever virus (ASFV) p54 protein and perform a Cloth-enzyme-linked immunosorbent assay (ELISA) for detecting the ASFV antibody in order to reduce risks posed by using the live virus in diagnostic assays.MethodWe used bioinformatics methods to predict the antigen epitope of the ASFV p54 protein in combination with the antigenic index and artificially synthesized the predicted antigen epitope peptides. Using ASFV-positive serum and specific monoclonal antibodies (mAbs), we performed indirect ELISA and blocking ELISA to verify the immunological properties of the predicted epitope polypeptide.ResultsThe results of our prediction revealed that the possible antigen epitope regions were A23–29, A36–45, A72–94, A114–120, A124–130, and A137–150. The indirect ELISA showed that the peptides A23–29, A36–45, A72–94, A114–120, and A137–150 have good antigenicity. Moreover, the A36–45 polypeptide can react specifically with the mAb secreted by hybridoma cells, and its binding site contains a minimum number of essential amino acids in the sequence 37DIQFINPY44.ConclusionsOur study confirmed a conservative antigenic site in the ASFV p54 protein and its amino acid sequence. A competitive ELISA method for detecting ASFV antibodies was established based on recombinant p54 and matching mAb. Moreover, testing the protein sequence alignment verified that the method can theoretically detect antibodies produced by pigs affected by nearly all ASFVs worldwide. 相似文献
154.
不同喷施浓度及喷施次数对蕹菜产量及茎叶锌含量的影响结果表明:喷施0.05%及0.1%的硫酸锌液均能提高蕹菜的产量,但以0.05%的处理对产量的提高作用最明显,浓度超过0.1%时,对蕹菜生长有抑制作用提高喷锌浓度,蕹菜锌含量的增加为叶片大于茎;喷施1~2次,有明显的增产效果,喷施超过2次反而减产;随着喷施次数的增加,蕹菜锌含量也增加。 相似文献
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大多数蔬菜根系分布较浅,对土壤含水量反应极为敏感,南方地区雨水较多,地下水位高,土壤上层积水,渍害严重,造成土壤水肥气热失调,经常引起蔬菜秧苗沤根和烂根,导致蔬菜显著减产甚至绝收。为探索蔬菜基地防渍新思路,近年来,我们在蔬菜基地采用埋设地下暗管的方法调节土壤含水量,当土壤含水量高于蔬菜根系活动要求时,打开地下暗管排水阀,排除土壤中的积水,当土壤含水量低于蔬菜根系活动需要时关闭排水阀,有效地解决了蔬菜排渍和用水矛盾,大幅度提高蔬菜产量和品质,获得了比较理想的效果,现将有关埋设方法和应用效果介绍如下。 相似文献
157.
AIM and METHODS: The immunohistochemical method was used to study the on synapsin express in hippocampal formation during spatial learning and memory in rats.RESULTS: (1) In control group there are diffuse brown granules without any obvious granular product in hippocampal formation and in model group there are synapsin products in the hippocampal formation ,especially in the subregion CA3 , CA4 and the dentate gyrus after water maze trained for one week. After two weeks water maze trained the hippocampal formation appear the same distribution of the product granules with darker staining. (2) The light dendity of synapsin products between the model and the control groups showed significant differences, that in the model group was highter than that in the control group (P<0.05). The light dendity of synapsin products increased with the training time from the first week to the second week in the model group. And there is no increase with the training time from the second week to the third week . The light dendity is higher in the CA3, CA4 subregion and the dentate gyrus than the CA1 and CA2 subregion (P<0.05).CONCLUSIONS: (1) As mentioned above, it is believed that the new synapes are formed in the hippocampal formation of the rat by spacial learning and memory training. (2) The CA3, CA4 subregion and the dentate gyrus are correlated with the spacial learning and memory. 相似文献
158.
原木灵芝孢子研究:(Ⅳ)未破壁孢子与破壁孢子的比较 总被引:22,自引:3,他引:19
扫描电镜观察表明,破壁前灵芝孢子形态完整,破壁后孢壁结构被破坏,通过透射电镜发现破壁孢子的孢内物质易被释放。观察结果表明,复合力场超微粉碎法的破壁率高,超声波—冻融破壁法的破壁效果也较好,而超声速超微气流粉碎法仅使大部分孢子变形,未破坏其孢壁结构。分析结果表明,破壁孢子粉(破壁率≥95%)的粗蛋白、总糖含量变化不大,但粗脂肪(6.35%)及水溶性多糖(2.18%)含量分别较未破壁的提高了38.95%和20.83%;锌、铜、铬、硒等微量元素的含量变化不大,但锰(20μg/g)和镍(5.2κg/g)的含量明显高于未破壁孢子。此外,包括牛磺酸在内的19种游离氨基酸含量也没有明显变化。 相似文献
159.
地面覆草对姜田小气候及生姜生长的影响 总被引:5,自引:0,他引:5
姜田地面覆草可显著增加土壤含水量,降低地温,提高空气相对湿度,但使气温稍升。尽管地面覆草未改变光强,但生姜长势与传统插草相似,因而最终产量未表现显著差异。地面覆草与插草的生姜长势及产量均极显著高于裸地 相似文献
160.