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排序方式: 共有603条查询结果,搜索用时 15 毫秒
1.
We developed an H5/H7 trivalent inactivated vaccine by using Re-11, Re-12, and H7-Re2 vaccine seed viruses, which were generated by reverse genetics and derived their HA genes from A/duck/Guizhou/S4184/2017(H5 N6)(DK/GZ/S4184/17)(a clade 2.3.4.4 d virus), A/chicken/Liaoning/SD007/2017(H5 N1)(CK/LN/SD007/17)(a clade 2.3.2.1 d virus), and A/chicken/Guangxi/SD098/2017(H7 N9)(CK/GX/SD098/17), respectively. The protective efficacy of this novel vaccine and that of the recently used H5/H7 bivalent inactivated vaccine against different H5 and H7 N9 viruses was evaluated in chickens. We found that the H5/H7 bivalent vaccine provided solid protection against the H7 N9 virus CK/GX/SD098/17, but only 50–60% protection against different H5 viruses. In contrast, the novel H5/H7 trivalent vaccine provided complete protection against the H5 and H7 viruses tested. Our study underscores the importance of timely updating of vaccines for avian influenza control.  相似文献   
2.
Big bluestem (Andropogon gerardii Vitman) and little bluestem [Schizachyrium scoparium (Michaux) Nash.] are native to the North America and are important forage grasses and ornamental grasses. Both grasses are proposed as ideal biomass producers for cellulosic ethanol production. To apply genetic transformation, which is an important tool for incorporating desirable agronomic traits into plants to both species, however requires an efficient and reproducible regeneration protocol. We used mature caryopses from big and little bluestem as explants and tested the effect of various combinations of 2, 4-dichlorophenoxyacetic acid (2, 4-D) (1, 2, 3, 4 or 5 mg l−1) and kinetin (KT) (0, 0.1 or 0.2 mg l−1) on embryogenic callus induction with LS as the basal medium. The highest percentage of embryogenic calli induction occurred on medium containing 2, 4-D alone at 2 mg l−1 for ‘Bison’ and on medium containing 4 mg l−1 2, 4-D alone for ‘Bonilla’ big bluestem. For little bluestem, the highest percentage of embryogenic callus induction occurred on medium containing 3 mg l−1 2, 4-D plus 0.1 mg l−1 kinetin, suggesting that addition of KT is beneficial. Shoot regeneration took place on LS basal medium without any plant growth regulator for both species, although the addition of KT increased both regeneration frequency and the number of shoots produced per callus. Rooting of shoots reaching about 2 cm long occurred readily with or without α-naphthaleneacetic acid (NAA). Rooted plantlets were all successfully established in the soil.  相似文献   
3.
本文简要介绍了8901小麦选育与开发的背景概况,系统总结了8901小麦的选育条件、关键技术、品种特性与产业化开发方面的进展,并阐述了对8901小麦今后应重点加强的研究领域。  相似文献   
4.
捻转血矛线虫(H.contortus)ZJ株H11蛋白基因的克隆及序列分析   总被引:2,自引:0,他引:2  
参照已发表的捻转血矛线虫H11蛋白基因序列设计引物,以H.contortuss ZJ株的总RNA为模板,进行RT—PCR扩增,成功扩增出H11基因。将PCR产物与pUCm—T载体连接后,转化DH5α感受态细胞,筛选阳性克隆并测序。序列分析表明,其核苷酸序列与国外报道的H11基因的同源性为99.5%。编码氨基酸序列具有氨基肽酶的保守序列,推测可使虫体不能获得所必需的氨基酸而导致死亡。  相似文献   
5.
从局域网的体系结构出发 ,阐述了无线局域网 (WLAN)的传输技术、发展现状、IEEE80 2 1 1、无线局域网技术标准、无线局域网的组网方式及无线局域网的应用前景  相似文献   
6.
两种复合肥在叶菜类蔬菜上的应用效果比较   总被引:1,自引:0,他引:1  
在山东省莱阳和寿光两地露地及保护地生长的芹菜和大白菜上进行新型复合肥 2 1 8 11S肥效研究 ,同时与市场上较为流行的 15 15 15S复合肥进行比较。结果表明 ,2 1 8 11S复合肥比 15 15 15S复合肥在增加产量、提高品质方面效果更好。 2 1 8 11S复合肥最佳用量大白菜为 14 14~ 170 0kg·hm-2 ,芹菜为 2 0 6 2~ 2 4 78kg·hm-2 。  相似文献   
7.
AIM: In order to study the relationship between the ERK and p38 MAPK activation and the protection of 11, 12-epoxyeicosatrienoic acid (11, 12-EET) and ischemia preconditioning (IP), the effects of 11, 12-EET and ischemic preconditioning on phosphorylated ERK and p38 MAPK during ischemia and reperfusion in rat myocardium were examined. METHODS: The rat heart was subjected to ischemia for 5 min by ligating the left anterior descending coronary artery followed by reperfusion for 5 min (two times) to undergo ischemia preconditioning. The rats were divided into 5 groups: (1) control; (2) sham group; (3) ischemia/reperfusion (I/R) group, in which the rat heart suffered from 60 min ischemia followed by 30 min reperfusion; (4) IP plus I/R group; (5) EET plus I/R group, in which 6.28×10-8 mol/L 11, 12-EET was injected intravenously 20 min before I/R. The heart function was examined, and phosphorylated ERK and p38 MAPK were detected by Western blot. RESULTS: At 30 min reperfusion, +dp/dtmax, -dp/dtmax and LVDP decreased significantly in I/R group compared with sham group, IP plus I/R group and EET plus I/R group; Phosphorylated ERK1/2 level was higher in I/R group than sham group, but was lower in I/R group than IP plus I/R group and EET plus I/R group; Phosphorylated p38 MAPK level was lower in control, sham, IP plus I/R and EET plus I/R group than I/R group. CONCLUSION: 11,12-EET protects rat heart against ischemia/reperfusion injury, the mechanism may be related to activation of ERK1/2 and inhibition of p38 MAPK.  相似文献   
8.
AIM: To establish a method for obtaining specific cells in solid tumor tissue by sorting of CD11b+ myeloid cells in hepatic metastases from colorectal cancer.METHODS: Tumor tissues were prepared into single cell suspension by mechanical method combined with enzyme digestion, and then the CD11b+ myeloid cells were isolated by flow cytometry. The sorted cells were identified by immunocytochemistry. The viability and morphologiy of the sorted cells were evaluated by Giemsa and Typan blue staining. The cell purity was evaluated by flow cytometry.RESULTS: Sufficient numbers of CD11b+ cells with high purity were isolated by sorting with flow cytometry from the single cell suspension prepared by mechanical and enzyme digestion. The purity of the cells was confirmed by statistical analysis (P<0.05). The positive rates of the cells before and after sorting were significantly different (P<0.01). The positive cells were verified by immunocytochemical method. Meanwhile, the sorted cells had complete morphology and good activity.CONCLUSION: The CD11b+ myeloid cells in solid tumor tissue can be isolated by flow cytometry from the machine-enzyme digestion suspension with high purity, good activity and complete morphology.  相似文献   
9.
条纹叶枯病是水稻(Oryza sativa L.)上最严重的病害之一。STV11是从籼稻Kasalath中鉴定的条纹叶枯病抗性基因,根据Kasalath型条纹叶枯病基因STV11 KAS6个碱基缺失的功能性多态性序列差异,设计基于PCR的功能性分子标记qstv11。利用此标记对299份试验材料[5份抗病品种、5份感病品种、41份辽宁省育种材料、17份日本粳型材料、142份秋光/七山占重组自交系(群体A)、85份笹锦/Habataki//笹锦回交重组自交系(群体B)、群体亲本4份]进行基因型分析并进行抗病性鉴定。结果表明,qstv11能够较好区分抗感基因型,而且在测试材料中与条纹叶枯抗性整体呈现共分离。41份辽宁材料中鉴定出含有STV11-R(抗)材料1份;日本粳型材料该位点均为STV11-S(感);群体A和B中分别筛选出粳稻背景STV11-R型材料24份和6份。  相似文献   
10.
赵畅  张淼  李法莲  邵群 《安徽农业科学》2007,35(12):3470-3474
土壤盐渍化是导致作物减产的一项重要原因,Na+对大多数作物是有害的,而钾是植物不可缺少的营养成分,植物根系在外界低钾条件下主要通过高亲和性系统吸收K+.介绍了高亲和钾转运体Trk/HKT和KUP/HAK/KT 2大家族的结构和功能.主要讨论了当植物处于K+饥饿及盐胁迫下,2大家族在改善植物钾营养、提高植物耐盐性方面的作用.  相似文献   
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