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41.
AIM: To observe the effect of beclin-1 silencing by the technique of RNA interference on the injury of human gastric cancer SGC-7901 cell by Sheliugu extract (the extract from tuber of Amorphophallus konjac, TuAKe). METHODS: To knock down the expression of beclin-1 gene, SGC-7901 cells were transfected with lentiviral vector carrying beclin-1-shRNA. The beclin-1 gene knock-down and non-knock-down SGC-7901 cells were treated with TuAKe. The cell viability was analyzed by CKK-8 assay. The percentages of apoptotic cells were detected by flow cytometry. The expression of beclin-1 and LC3 was detected by Western blot. RESULTS: The beclin-1 gene silencing decreased the protein expression of beclin-1 and increased the protein expression of LC3 in the SGC-7901 cells, leading to the decrease in cell viability and the increase in apoptotic rate (P<0.05). TuAKe increased the protein expression of beclin-1 and LC3 in the SGC-7901 cells, and decreased the protein expression of LC3 in the SGC-7901 cells with beclin-1 gene silencing, thus inhibiting the cell viability and increasing the apoptotic rate (P<0.05). CONCLUSION: Beclin-1 gene silencing inhibits the activation of beclin-1-related signaling pathway in gastric cancer SGC-7901 cells, and aggravates the injury of cell viability induced by TuAKe. 相似文献
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Herbage production,nutritive value and animal productivity within hardwood silvopasture,open and mixed pasture systems in Appalachia,United States 下载免费PDF全文
Demand for livestock food products is projected to increase dramatically through to 2050. Increased livestock production capacity on marginal lands will be critical to meeting this demand. A 5‐year research effort was undertaken to evaluate lamb and sward productivity within open and hardwood silvopasture (SP) systems in Appalachia, USA. Grazing began in mid to late April each year, with the grazing season averaging 141 d. Grazing system treatments during 2002 and 2003 grazing seasons were as follows: 100% open pasture (OP), 67% OP and 33% SP, and 67% OP and 33% SP with delayed SP grazing initiation (OSD). In 2004, a 100% SP (SP) system was added. Animals were rotationally stocked through either 6 (2002–2004) or 7 (2005–2006) paddocks. Open pasture produced greater (P < 0·001) grazing season herbage yield, while all systems generated similar animal performance. Based on summer solstice, herbage production in spring was greater (P < 0·001) than summer, except in 2003. Total non‐structural carbohydrate (TNC) content was greater (P < 0·05) in spring than in summer, except in 2004. Animal performance was superior in spring versus summer (P < 0·001). Animal plasma urea nitrogen (PUN) was lower (P < 0·05) for OP in 2003. When PUN was correlated with nutritive value indicators, the ratio of TNC to crude protein (CP) had the strongest correlation. The strong correlation indicates the need for synchronized ruminal energy and CP availability. Development of silvopasture from existing woodlots has potential to improve whole farm productivity on marginal lands. 相似文献
44.
耕作方式及秸秆还田对土壤性质、微生物碳源代谢及小麦产量的影响 总被引:1,自引:0,他引:1
以小麦品种济麦22为试验材料,采用裂区试验设计,耕作方式为主区,分别设常规翻耕(C)、深松(S)、旋耕(R)处理,副区为秸秆还田量,分别设秸秆全还田(P)和秸秆不还田(A)处理,采用Biolog Eco技术测定土壤微生物碳源代谢功能,并分析土壤基本理化性质和作物产量。结果显示:深松与秸秆还田均有利于土壤含水量和有机碳含量的提高,0~15 cm土层分别提高了9.78%和24.00%,15~30 cm土层分别提高了7.08%和15.81%;深松提高了15~30 cm土层的pH值6.67%,秸秆还田提高了0~15 cm土层的pH值4.32%。深松和秸秆还田均有利于代谢多样性(丰富度指数、香浓多样性指数)、碳源代谢强度的提高,0~15 cm土层分别提高了26.84%、3.84%和38.02%,15~30 cm土层分别提高了11.87%、 3.63%和14.74%。主成分分析表明常规翻耕秸秆不还田和旋耕耕作秸秆不还田碳源代谢功能相近,15~30 cm层次内常规翻耕秸秆全还田碳源代谢功能和深松耕作秸秆全还田处理相近。深松和秸秆还田平均提高了小麦产量5.82%,微生物碳源代谢功能与小麦产量具有极显著的相关性。 相似文献
45.
Protective efficacy of an H5/H7 trivalent inactivated vaccine produced from Re-11, Re-12, and H7-Re2 strains against challenge with different H5 and H7 viruses in chickens 下载免费PDF全文
ZENG Xian-ying CHEN Xiao-han MA Shu-jie WU Jiao-jiao BAO Hong-mei PAN Shu-xin LIU Yan-jing DENG Guo-hua SHI Jian-zhong CHEN Pu-cheng JIANG Yong-ping LI Yan-bing HU Jing-lei LU Tong MAO Sheng-gang GUO Xing-fu LIU Jing-li TIAN Guo-bin CHEN Hua-lan 《农业科学学报》2020,19(9):2294-2300
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
46.
Do cover crops change the lability of phosphorus in a clayey subtropical soil under different phosphate fertilizers? 下载免费PDF全文
A. P. B. Teles M. Rodrigues W. F. Bejarano Herrera A. Soltangheisi L. R. Sartor P. J. A. Withers P. S. Pavinato 《Soil Use and Management》2017,33(1):34-44
Plants have developed different mechanisms to absorb and solubilize phosphorus (P) in the soil, especially in environments with low P availability. This study evaluated the effects of different winter cover crops on soil P availability in a clayey subtropical (Hapludox) soil receiving soluble P fertilizer and a rock phosphate applied to the summer crop, under no‐tillage. The experiment was carried out over 3 yrs (2009–2011) with five different cover crop species: common vetch, fodder radish, ryegrass, black oat, white clover and fallow as control. The soil was sampled after the third year of cover crop cultivation and analysed for inorganic and organic P forms according to the well‐established Hedley fractionation procedure. Phosphate fertilizers promoted accumulation of both labile and nonlabile P pools in soil in the near surface layer, especially under rock phosphate. Fertilizer applications were not able to change P fractions in deeper layers, emphasizing that the Brazilian clayey soils are a sink of P from fertilizer and its mobility is almost nil. Although the cover crops recycled a great amount of P in tissue, in a short‐term evaluation (3 yrs) they only changed the content of moderately labile P in soil, indicating that long‐term studies are needed for more conclusive results. 相似文献
47.
养殖密度对硝化型生物絮团系统中凡纳滨对虾生长和水质的影响 总被引:1,自引:0,他引:1
利用硝化型生物絮团系统进行凡纳滨对虾的养殖,并通过设置不同的养殖密度探究不同养殖密度下硝化型生物絮团系统对凡纳滨对虾生长性能和水质情况的影响。实验选择同一批标粗到一定规格的健康凡纳滨对虾[体长(4.80±0.25) cm,体质量(0.98±0.16)g],分成5个密度梯度组放养到养殖池中,进行为期45 d的养殖。结果表明:80~610尾/m~3范围内,硝化型生物絮团系统对非离子氨和亚硝酸盐氮可以控制在警戒浓度(0.2 mg/L)附近波动,为凡纳滨对虾健康生长提供了良好的环境,保证养殖存活率,另外该系统下适当的排污可以避免高密度养殖下硝酸盐氮积累太快;80~610尾/m~3时存活率随密度升高而下降,但产量随密度升高而增加。 相似文献
48.
文中基于中国、美国、俄罗斯、印度、巴西、印度尼西亚6国2000—2014年投入产出数据,通过测算中间需求率、中间投入率、感应度系数和影响力系数,对林产工业产业关联与波及效应进行动态比较分析。研究结果表明:相较于其他国家,中国木材加工业、造纸业的中间产品型产业特征明显,对国民经济贡献程度较高,但同时也面临成为“瓶颈产业”的风险;中国家具制造业的最终需求型产业性质显著,受整体经济发展的拉动作用明显弱于其他国家。总体而言,中国林产工业对国民经济的推动作用整体上高于国民经济发展对其的拉动作用。需要重点提升木材加工业、家具制造业整体产业链竞争力,加大科研创新投入力度以提升产出效率,并进一步提高家具制造业整体产品的附加值。 相似文献
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为了明确苹果锈果类病毒(apple scar skin viroid,ASSVd)引起的苹果花脸病在田间的病情发展情况以及ASSVd在组培条件下的传播方式,2012—2015年对河北省顺平南神南村3个果园进行持续调查和检测。结果显示,果园A、B、C的显症率分别从3.00%、19.35%和10.00%上升至10.00%、34.41%和22.00%,带毒率分别从11.00%、20.43%和14.00%上升至23.00%、37.63%和30.00%,带毒率和显症率都逐年增加,而且带毒率大于显症率,即有些带毒果树不显症。发病果树田间分布有明显的发病中心。通过高通量测序发现显症果树ASSVd vsiRNA reads数是带毒未显症reads数的4.08倍,同时实时荧光定量PCR检测发现显症树ASSVd病毒积累量显著高于带毒未显症树。以携带ASSVd的组培苗和无毒组培苗为试材,利用RT-PCR检测明确了ASSVd可通过伤口沾染带毒汁液、组培剪污染、含毒培养基、根系接触进行传播,其中根系接触传染率较高。 相似文献