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81.
论述乡村振兴背景下新型农业人才培养的必要性。分析新时代新型农业人才培养面临的主要问题,表现为新型农业人才不足且农村人才整体水平较低,新型农业人才引进、培养和激励机制建设力度不足。提出新时代新型农业人才培养对策,包括农业高校建立新型农业人才培养体系,健全新型农业人才引进、培养和激励机制,校企联合、产学研结合培养新型农业人才。 相似文献
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84.
澳大利亚是一个典型的岛屿国家,地域辽阔。18世纪欧洲移民时期至今,新移民为澳大利亚带来了大量外来物种,其中一部分在很大程度上丰富了澳大利亚的农产品种类,但也有很多物种已经成为危害自然生态环境和农牧业发展的有害入侵物种。澳大利亚政府高度重视外来入侵物种和本国生物资源的管理工作,建立了完善的政策法规、管理机构、技术支撑、资金保障、公共教育体系,在国际生物多样性保护与利用方面处于世界领先水平。本文简要介绍了澳大利亚外来入侵物种管理的有关策略和指南,并阐述了对中国的借鉴意义:(1)建立完善国内生物多样性保护特别是外来入侵物种防控的法律法规体系;(2)建立健全国内生物多样性管理长效机制;(3)建立高效生物多样可持续管理资金保障体系;(4)构建全方位全民参与的生态保护宣传培训体系;(5)强化科学技术对生物多样性管理的支撑作用。 相似文献
85.
Chia-Chi Peng Chiung-Yao Huang Atallah F. Ahmed Tsong-Long Hwang Jyh-Horng Sheu 《Marine drugs》2020,18(11)
The present investigation on chemical constituents of the soft coral Sarcophyton cherbonnieri resulted in the isolation of seven new cembranoids, cherbonolides F–L (1–7). The chemical structures of 1–7 were determined by spectroscopic methods, including infrared, one- and two-dimensional (1D and 2D) NMR (COSY, HSQC, HMBC, and NOESY), MS experiments, and a chemical reduction of hydroperoxide by triphenylphosphine. The anti-inflammatory activities of 1–7 against neutrophil proinflammatory responses were evaluated by measuring their inhibitory ability toward N-formyl-methionyl-leucyl-phenylalanine/cytochalasin B (fMLF/CB)-induced superoxide anion generation and elastase release in primary human neutrophils. The results showed that all isolates exhibited moderate activities, while cherbonolide G (2) and cherbonolide H (3) displayed a more active effect than others on the inhibition of elastase release (48.2% ± 6.2%) and superoxide anion generation (44.5% ± 4.6%) at 30 µM, respectively. 相似文献
86.
It has been found that fibroblast growth factor receptor (FGF-FGFR) signaling can regulate the expression of adipocyte differentiation genes. FGF9 is one of the members of FGFs that mainly binds receptors FGFR2 and FGFR3. FGF9 is highly expressed in the adipose tissue of humans and mice, but there are few reports on the role of FGF9 in goat intramuscular adipocyte differentiation. Therefore, this study explored the effect of FGF9 on adipocyte differentiation through cell culture, interference, and overexpression. The expression of receptors FGFR1–FGFR4 in adipocyte differentiation and their effects on differentiation were detected to screen receptor gene of FGF9. Finally, the interaction between FGF9 and the receptor was tested by cotransfection. Our results showed that FGF9 interacts with FGFR2 to inhibit goat intramuscular adipocyte differentiation by regulating peroxisome proliferator-activated receptor gamma (PPARγ) and preadipocyte factor 1 (Pref1), which is a data support for subsequent pathway research. 相似文献
87.
小浆果因具有较高的营养价值和保健作用深受人们喜爱,被国际市场誉为第3代水果。随着市场需求量的增加,林业小浆果的智能采摘与分选成为一种新的趋势。目前,由于现有技术自动化和智能化程度不高,导致大量人力、物力的投入。深度学习方法的飞速发展促进了检测技术的精确作业和检测精度的提高。文中概述了深度学习的发展进程,通过总结国内外关于深度学习方法在小浆果采摘与分选中的应用,提出深度学习方法在实际应用过程中存在的问题及解决措施,并展望深度学习方法在小浆果智能采摘与分选检测方面的发展趋势。 相似文献
88.
Qianqian Huang Heizhao Lin Ruixuan Wang Zhong Huang Chuanpeng Zhou Wei Yu Pengwei Xun Lianjie Tan Yun Wang Jun Wang 《Aquaculture Research》2019,50(9):2359-2370
In order to investigate the dietary vitamin B6 (VB6) requirement for juvenile golden pompano, an experiment of six different diets with six dietary VB6 levels (0, 3.75, 7.47, 10.6, 13.7 and 18.5 mg/kg) was conducted. The results indicated that the content of dietary VB6 significantly increased weight gain rate (WGR), specific growth rate (SGR) and feed conversion ratio (FCR; p < 0.05). Golden pompano fed diet containing 7.47 mg/kg VB6 achieved the maximum ALT, AST, GPx, hepatic VB6 concentrations as well as the minimum MDA, however, the ALT, AST, GPx and hepatic VB6 concentrations decreased while MDA increased with a further increase in dieatry VB6. The highest values of GR and POD occurred at the 10.6 and 13.7 mg/kg dietary VB6 (p < 0.05) respectively. A diet supplemented with 7.47 mg/kg VB6 increased intestinal Na+, K+‐ATPase, Chymotrypsin, γ‐glutamyl transpeptidase, creatine kinase and amylase activities (p < 0.05). The relative abundance of Tenericutes and Bacteroidetes decreased while Proteobacteria and Firmicutes improved with an increase in dietary VB6 levels up to 7.47 mg/kg. Quadratic regression analysis on WGR, hepatic VB6 concentrations, AST and ALT indicated that the optimum dietary VB6 levels for juvenile golden pompano were 8.84–9.28 mg/kg. 相似文献
89.
Denicia Atujona Yucong Huang Zhiwen Wang Jichang Jian Shuanghu Cai 《Aquaculture Research》2019,50(9):2628-2634
Despite significant improvements in aquaculture to compensate wild catch, disease organisms have thrived in limiting its national and global potential. Using antibiotics, in a bid to remedy the havoc, has given rise to complications, attracting attention to disease prevention by immune enhancement against diseases. Grouper production has been inhibited for the threats of bacterial infection, particularly of Vibrio origin. Considering the rise in vibriosis cases, improved vaccines are necessary; moreover, recombinant vaccines, the choice for trial in the present experiment have been effective and more specific in improving immunity. The current work deals with grouper immune system enhancement with a recombinant vaccine developed from VirB11 gene in Vibrio harveyi. VirB11 was cloned in V. harveyi for recombinant vaccine development against vibriosis in orange‐spotted grouper (Epinephelus coioides). As indicated by the results, recombinant VirB11 protein showed effectiveness in conferring protection against vibriosis with observable specific antibody response in enzyme‐linked immunosorbent assay (ELISA) analysis; a significant increase (p < 0.05) in antibody levels was observed after a week and after 8 weeks post‐vaccination. From the weeks post‐vaccination, log2 (antibody titres) in the sera of vaccinated groups reached a peak of 14.2 at week 5 in the vaccinated group in comparison with a peak of approximately 5 and 2 in adjuvant and PBS controls. As indicated by the challenge results, 90% relative survival was observed in vaccinated group and 13% relative survival in control group I (adjuvant control). The cumulative performance of protein concludes VirB11 commendable for recombinant vaccine development. 相似文献
90.
Weini Zhang Zichao Liao Fengxiao Hu Xinhua Chen Xiaohong Huang 《Aquaculture Research》2019,50(12):3559-3566
Outer membrane proteins (Omps) of Gram‐negative bacteria have been proven to be efficient subunit vaccines against bacteriosis. In this study, OmpF and OmpK of Aeromonas hydrophila were expressed, and their immune protective effects in European eel (Anguilla anguilla) were evaluated. The genomic DNA of A. hydrophila 322A was used as a template, and two kinds of prokaryotic expression plasmids, pET‐32a‐OmpF and pET‐32a‐OmpK, were constructed. Recombinant OmpF protein (r‐OmpF) and r‐OmpK were purified and were proven to have antigenicity by Western‐blot analysis. r‐OmpF and r‐OmpK were used as immunogens to immunize European eel by intraperitoneal injection. The mRNA expression of 6 immune‐related genes (IgM, IL‐10, IRF3, IRF7, LysG4 and HexB) in the liver tissues of eels at 1 hr, 3 hr, 6 hr, 12 hr, 24 hr, 72 hr and 10 days postimmunization was analysed by real‐time PCR. At 30 dpi, the serum antibody response was measured by ELISA. Fish were attacked at 15 dpi by live 322A to assess the protective immunity of r‐OmpF and r‐OmpK. All the six tested genes responded to r‐OmpF or r‐OmpK vaccination at varying degrees. The serum antibody titre of r‐OmpF‐ and r‐OmpK‐immunized groups was 1:1,600 and 1:3,200 respectively. In addition, r‐OmpF gave 35.5% of the relative immune protection rate to European eels, while r‐OmpK gave 70.0%. By analysing the protective immunity and the regulatory role in the immune‐related gene expression of the two recombinant proteins that were studied, it was found that r‐OmpK was a potential vaccine candidate against A. hydrophila. 相似文献