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31.
通过调研山东75家新型农业经营组织生产情况,分析规模生产条件下山东小麦玉米种植规格、各环节作业方式和机械配备等生产现状与存在问题,提出了一种适合规模化生产的小麦玉米机械化种植模式,并对各环节作业提出了技术要求。   相似文献   
32.
为提高全株藜麦的饲料化利用率,寻找其与全株玉米的最佳青贮比,试验共设全株藜麦与全株玉米比为100:0,90:10,80:20等11个组合进行青贮发酵,发酵60 d后测定各组青贮料的体外产气发酵指标,使用灰色关联度分析筛选出最佳青贮比例。结果表明,体外发酵至36 h时,各处理组GP趋于稳定,体外发酵减弱接近停止;全株藜麦与全株玉米比例为90:10时,该青贮饲料组合的粗蛋白(CP)和粗脂肪(EE)含量显著高于其他各组(P<0.05),乙酸(AA)、总挥发性脂肪酸(TVFA)含量以及氨态氮(NH3-N)浓度显著高于其他各处理(P<0.05)。分析表明,全株藜麦与全株玉米比例为90:10时,混合青贮饲料的营养品质和产气发酵特性综合表现最好,可作为优质混合青贮饲料在家畜养殖中推广使用。  相似文献   
33.
AIM:To study whether homocysteine (Hcy) inhibits the expression of ATP-binding cassette transporter A1 (ABCA1) and ATP-binding cassette transporter G1 (ABCG1) by microRNA-33 (miRNA-33) signaling, and reduces the efficiency of reverse cholesterol transport (RCT).METHODS:RAW264.7 macrophages were induced by oxidized low-density lipoprotein (ox-LDL) to establish foam cell model. Oil red O staining was used to determine whether the model was established successfully. miRNA-33 mimics and miRNA-33 inhibitor were transfected into the cells by Lipofectamine 2000, and the cells were exposed to Hcy at concentration of 5 mmol/L for 24 h. The intracellular lipid droplets were observed by Oil red O staining. The expression of ABCA1 and ABCG1 at mRNA and protein levels was determined by real-time PCR and Western blot. The cellular cholesterol content was analyzed by HPLC, and effluent rate of cholesterol was detected by the method of liquid scintillation counting.RESULTS:Compared with blank control group, the lipid content in miRNA-33 mimics group was increased, and the expression of ABCA1 and ABCG1 at mRNA and protein levels was decreased (P<0.05). The intracellular cholesterol content was increased gradually (P<0.05), and the cellular cholesterol efflux rate was gradually decreased (P<0.05) in miRNA-33 mimics group. Compared with blank control group, the testing results in miRNA-33 inhibitor group were the opposition of those in miRNA-33 mimics group (P<0.05). No diffe-rence of the above indexes among blank control group, miRNA-33 mimics-NC group and miRNA-33 inhibitor-NC group was observed.CONCLUSION:Hcy inhibits the mRNA and protein expression of ABCA1 and ABCG1 through miRNA-33 signaling, and reduces the efficiency of RCT in RAW264.7 macrophage-derived foam cells.  相似文献   
34.
The prognosis of liver cancer was inferior among tumors. New medicine treatments are urgently needed. In this study, a novel exopolysaccharide EPS364 was purified from Vibrio alginolyticus 364, which was isolated from a deep-sea cold seep of the South China Sea. Further research showed that EPS364 consisted of mannose, glucosamine, gluconic acid, galactosamine and arabinose with a molar ratio of 5:9:3.4:0.5:0.8. The relative molecular weight of EPS364 was 14.8 kDa. Our results further revealed that EPS364 was a β-linked and phosphorylated polysaccharide. Notably, EPS364 exhibited a significant antitumor activity, with inducing apoptosis, dissipation of the mitochondrial membrane potential (MMP) and generation of reactive oxygen species (ROS) in Huh7.5 liver cancer cells. Proteomic and quantitative real-time PCR analyses indicated that EPS364 inhibited cancer cell growth and adhesion via targeting the FGF19-FGFR4 signaling pathway. These findings suggest that EPS364 is a promising antitumor agent for pharmacotherapy.  相似文献   
35.
为探索红枣GSTU类基因在红枣抗逆中的分子作用机制,本研究以狗头枣枣树叶片的DNA为模板,根据枣GSTU基因的序列(HM345954.1)设计引物,采用PCR方法获得GSTU基因序列,并利用生物信息学手段对其所对应蛋白的结构域、功能域、理化特性、跨膜区、二级结构及亚细胞定位等进行分析。结果表明:克隆到的DNA序列全长838 bp,具有2个外显子和1个内含子,内含子在292~460 bp碱基处,该序列与GenBank中枣的GSTU核苷酸序列和氨基酸序列的同源性分别为99.85%和100%,表明成功的克隆了狗头枣的GSTU基因。该序列编码222个氨基酸,分子量为25.268 kD,理论等电点(pI)为6.10;亲水性的平均数为-0.242,表明该蛋白是亲水性蛋白。二级结构主要以α-螺旋为主,其次是无规则卷曲,不存在信号肽,表明该蛋白可能为非分泌性蛋白,该蛋白可能位于内质网(膜)和质膜上。本研究获得的狗头枣GSTU基因在基因结构上含有1个内含子,在核酸序列及氨基酸序列上与GenBank中枣的GSTU基因同源性高,并对其理化性质、结构等进行了预测与分析,为进一步研究红枣抗逆分子机制提供理论基础,同时为红枣品种的选育提供理论支持。  相似文献   
36.
为合理使用低毒农药防治水稻粘虫,2015年7月在广西乐业县同乐镇和甘田镇进行25%灭幼脲悬浮剂和2.2%甲氨基阿维菌素苯甲酸盐微乳剂防治粘虫大田示范试验。结果表明:施药后17 d,核心区25%灭幼脲对粘虫的防治效果和保叶率分别为96.19%和94.73%,在培训指导农民防治示范区的防效分别为93.50%和95.10%;施药后10 d,核心区2.2%甲氨基阿维菌素苯甲酸盐对粘虫的防治效果和保叶率分别为96.61%和97.35%,在培训指导农民防治示范区的防效分别为90.07%和89.59%。25%灭幼脲和2.2%甲氨基阿维菌素苯甲酸盐处理区对粘虫的防效均要高于农民自防区。  相似文献   
37.
杨霏  邹瑞  张玥  杨自云  吴田 《种子》2020,(4):46-49,54
为了保护珍贵的十里香茶树资源,掌握利于十里香茶的最优组培条件,本研究对十里香茶组培过程中外植体类型、消毒时间、培养基添加物及培养条件进行了筛选。结果表明,采用轻微木质化的带腋芽茎段经升汞消毒15 min,接种后暗培养5 d,MS+0.2 mg·L^-1 NAA培养基中添加3 mg·L^-1 PVP+2000 mg·L^-1 Vc或者6 mg·L^-1 PVP+3000 mg·L^-1 AC,可在低污染率的前提下将褐化率降为10%左右,一定程度上解决了茶树组培中褐化率高的难题;采用1/8 MS+1 mg·L^-1 IBA培养基有利于外植体生根且增殖迅速。本研究建立了十里香茶的无菌苗离体培养及再生体系,可通过组培手段对其进行大量繁殖。  相似文献   
38.
Bactrocera bryoniae and Bactrocera neohumeralis are highly destructive and major biosecurity/quarantine pests of fruit and vegetable in the tropical and subtropical regions in the South Pacific and Australia. Although these pests have not established in China, precautions must be taken due to their highly destructive nature. Thus, we predicted the potential geographic distribution of B. bryoniae and B. neohumeralis across the world and in particular China by ecological niche modeling of the Maximum Entropy(Max Ent) model with the occurrence records of these two species. Bactrocera bryoniae and B. neohumeralis exhibit similar potential geographic distribution ranges across the world and in China, and each species was predicted to be able to distribute to over 20% of the globe. Globally, the potential geographic distribution ranges for these two fruit fly species included southern Asia, the central and the southeast coast of Africa, southern North America, northern and central South America, and Australia. While within China, most of the southern Yangtze River area was found suitable for these species. Notably, southern China was considered to have the highest risk of B. bryoniae and B. neohumeralis invasions. Our study identifies the regions at high risk for potential establishment of B. bryoniae and B. neohumeralis in the world and in particular China, and informs the development of inspection and biosecurity/quarantine measures to prevent and control their invasions.  相似文献   
39.
草地贪夜蛾幼虫龄期对自相残杀行为的影响   总被引:3,自引:0,他引:3  
对群体饲养下草地贪夜蛾幼虫在不同龄期的自相残杀行为进行了比较研究,结果表明:在4种密度(5、10、20头/瓶和30头/瓶)下,不同龄期的幼虫自相残杀率差异显著,不同密度下的自相残杀行为主要集中在5龄幼虫,其自相残杀率均在5龄第2天时最高,在5、10、20和30头/瓶中分别为(14.34±3.28)%、(17.94±3.26)%、(18.21±3.47)%和(27.05±5.52)%,幼虫在5龄前的自相残杀行为并不明显。进一步测定发现,相同数量的4龄和5龄幼虫混合后在3种密度(4、10和20头/瓶)下的自相残杀率无显著差异(F=2.29,df=2,P>0.05),但随着幼虫密度的增加,死亡的4龄幼虫占总死亡个体的比例升高,而死亡的5龄幼虫所占比例下降。这说明草地贪夜蛾同一龄期的幼虫自相残杀行为具有明显的龄期依赖性,自相残杀行为主要发生在高龄幼虫间。低龄和高龄幼虫同时存在时低龄幼虫被残杀的比例较高。试验结果对于草地贪夜蛾的室内大量饲养具有一定借鉴作用。  相似文献   
40.
AIM: To investigate the autophagy of human ovarian cancer SKOV3 cells induced by cepharanthine and to explore its mechanism. METHODS: The effect of cepharanthine on the viability of ovarian cancer SKOV3 cells was measured by CCK-8 assay. The SKOV3 cells were treated with cepharanthine, and then the formation of autophagosome was observed with acridine orange staining under fluorescence microscope. The protein levels of LC3, AKT, p-AKT, mTOR, p-mTOR and GAPDH in the SKOV3 cells treated with cepharanthine were determined by Western blot.RESULTS: Cepharanthine significantly inhibited the viability of ovarian cancer SKOV3 cells in a dose-dependent manner (P<0.05). The number of the intracellular acidic autophagosomes with bright red fluorescence was significantly increased after cepharanthine treatment in the SKOV3 cells. The expression of LC3-Ⅱ in SKOV3 cells was significantly enhanced after cepharanthine treatment. Furthermore, treatment with cepharanthine in the SKOV3 cells also resulted in a significant down-regulation of phosphorylated form of AKT and mTOR (P<0.01), while the total protein level was not changed. Combination of cepharanthine and 3-methyladenine resulted in a substantial decrease in the cell viability compared with using cepharanthine alone.CONCLUSION: Cepharanthine significantly inhibits the growth of human ovarian cancer SKOV3 cells and induces the autophagy, which may be correlated with down-regulation of PI3K/AKT/mTOR signaling pathway.  相似文献   
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