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901.
902.
为大量饲养天敌昆虫,寻找种植寄主植物适宜的方法,研究了蛭石、草碳、珍珠岩、土对蚕豆苗生长的影响以及不同基质种植蚕豆的经济效益.结果表明:单一使用珍珠岩种植蚕豆苗时,由于保水性能差,蚕豆苗的苗高、鲜重均明显低于其他栽培基质,30 d时分别为26.8 cm、148.2 g,差异显著.而单一使用蛭石时,由于缺乏黏结能力,不易固定根系,易倒伏.用蛭石和草碳混配后,再加入少量的土,可改善栽培基质的保水性和疏松性,30 d时苗高和鲜重分别达35.3 cm和185.9 g,生长后期用营养液进行浇灌,可提高蚕豆苗生长势,避免苗高倒伏.  相似文献   
903.
国内洋桔梗组培快繁技术的研究进展   总被引:2,自引:0,他引:2  
通过查阅现有洋桔梗组织培养资料,对洋桔梗组培快繁技术体系的研究进展进行了综述,主要介绍了洋桔梗组织培养中的外植体的选择、初代培养、增殖培养、生根培养及练苗移栽等程序的研究进展.  相似文献   
904.
利用观赏茄子的一个分枝作砧木,观赏番茄作接穗;观赏番茄的一个侧枝作砧木,观赏茄子作接穗进行观赏番茄观赏茄子双向嫁接研究。试验结果表明,观赏番茄作接穗时嫁接成活率明显高于观赏茄子作接穗时的嫁接成活率,能否嫁接成活与嫁接时的砧木、接穗的茎粗有一定的关系,本试验中观赏番茄、观赏茄子茎粗在0.5 cm时嫁接成活率最高。  相似文献   
905.
两种鹅膏菌纯培养菌丝的分离培养和生长形态   总被引:3,自引:0,他引:3  
采集并组织分离到假褐云斑鹅膏(Amanita pseudoporphyria)和块鳞鹅膏(Amanita spissa)的纯培养菌丝.对2株鹅膏菌的培养发现虽然分离成功率很低,但是菌丝培养相对容易,在普通琼脂培养基上生长良好;2种鹅膏菌菌丝的生长形态和方式存在较大差别,对氨基酸的利用也存在差别,但是气生菌丝的延伸速率却非常相似.液体培养条件下,假褐云斑鹅膏菌丝体干重达到0.726mg·mL-1,块鳞鹅膏干重达到0.424mg·mL-1.  相似文献   
906.
AIM: To investigate the effect of irbesartan on the fatty liver of db/db mice and whether autophagy is involved in the process. METHODS: Male db/db mice (n=24) were randomly divided into model group and irbesartan group, and 12 db/m mice with similar age and weight were selected as normal control group. After 16 weeks of intervention respectively, the fatty liver-related parameters including body weight, liver index, blood lipid, liver function and pathological changes in the liver were observed. The protein levels of p-PI3K, p-Akt, and p-mTOR, as well as Atg-7, beclin-1 and LC3B in the liver tissues were detected by Western blot, and the autophagosomes in the liver were observed under electron microscope. RESULTS: Compared with the model group, the body weight, liver index, blood lipids, alanine and aspartate aminotransferase were decreased in irbesartan group (P<0.05). Moreover, the pathological changes in the liver were significantly ameliorated in irbesartan group than that of model group. Importantly, the protein levels of p-PI3K, p-Akt and p-mTOR were decreased with irbesartan administration, while the expression of Atg-7, beclin-1 and LC3B-Ⅱ was increased(P<0.05), which resulted in a distinct increase in autophagosomes. CONCLUSION: Irbesartan alleviates hepatic steatosis in db/db mice by inhibiting the PI3K/Akt/mTOR signaling pathway and upregulating the protein expression of Atg-7, beclin-1 and LC3B-Ⅱ, thereby inducing autophagy in hepatocytes.  相似文献   
907.
AIM: To study the effect of p65 gene silencing by adeno-associated virus type 9 (AAV9)-mediated RNA interference on angiotensin Ⅱ (Ang Ⅱ; 10-6 mol/L for 24 h)-induced apoptosis of rat ventricular H9c2 myocytes, and to elucidate the possible mechanism. METHODS: The H9c2 cells were transfected with rAAV9-eGFP and rAAV9-eGFP-NF-κB p65-siRNA at multiplicity of infection (MOI)=4×106 vg/cell. eGFP expression in the cells was observed under an inverted fluorescence microscope, and the percentage of eGFP positive cells was determined by flow cytometry. The expression of p65 was determined by Western blot. CCK-8 assay was used to measured the viability of transfected H9c2 cells. The apoptosis of the cells transfected with the virus and with Ang Ⅱ stimulation was analyzed by flow cytometry. RESULTS: The cells began to exhibit eGFP expression on the 2nd day after transfection. The fluorescence intensity was increased over the time of transfection. eGFP expression reached the maximum on the 5th day, and the transfection efficiency was (52.7±1.9)% at this time point. Compared with blank control group, no significant effect of AAV9 on the viability of H9c2 cells was observed. In resting state, p65 in the H9c2 cells had a certain activity. After Ang Ⅱ stimulation, the activity of p65 was obviously increased, while transfection of rAAV9-eGFP-NF-κB p65-siRNA effectively inhibited the expression of p65. The apoptosis of H9c2 cells in Ang Ⅱ stimulation group was significantly higher than that in blank control group, while transfection of rAAV9-eGFP-NF-κB p65-siRNA effectively inhibited apoptosis of H9c2 cells. CONCLUSION: Transfection of rAAV9-eGFP-NF-κB p65-siRNA effectively inhibits the expression of p65 gene of NF-κB pathway in the H9c2 cells without causing cell growth inhibition, and reduces the apoptosis induced by Ang Ⅱ.  相似文献   
908.
在阳台上水培苦苣,通过测量苦苣的形态指标、叶绿素、产量和品质等指标,以期筛选出比较适合阳台水培苦苣的营养液配方。结果表明,经郑州市蔬菜研究所的营养液配方处理的阳台水培苦苣株高、叶片数、叶面积、叶绿素含量、产量、VC含量、可溶性糖含量、总蛋白质含量均显著高于其他各处理,硝酸盐含量较低。  相似文献   
909.
试验旨在研究蓝狐MITF-M基因核心启动子活性区、转录因子结合位点、基因编码蛋白结构及功能,为探究该基因的表达调控机制提供理论依据。从成年蓝狐背部皮肤组织中采集1 cm×1 cm样品,采用RT-PCR扩增及测序技术首次获得MITF-M基因序列3 880 bp(包括5'侧翼区2 262 bp、CDS区1 260 bp、3'侧翼区358 bp),编码419个氨基酸残基。生物信息学分析结果显示,蓝狐MITF-M基因5'侧翼区存在潜在的启动子区域(-86~-336 bp),且发现TATA框、CAAT框、GC框和CRE等调控元件及CREB、LSF和Sp1等多种转录因子。MITF-M基因编码的蛋白是定位于细胞核和细胞质的不稳定、可溶性亲水蛋白质。亚细胞定位结果提示该蛋白在细胞核、细胞质和线粒体的概率较高,分别为65.2%、17.4%和8.7%。DNAMAN软件对MITF-M基因编码蛋白的二级结构预测发现,该蛋白由α螺旋(33.66%)、β折叠(16.66%)和无规卷曲(49.68%)组成,且不存在跨膜区域和信号肽。蓝狐与其他物种MITF-M基因编码的氨基酸序列同源性对比和系统进化树分析均提示蓝狐与犬的遗传亲缘关系最近,与哺乳动物和禽类均具有较高的同源性(>89.1%),说明MITF-M基因编码区在物种进化过程中较为保守。本研究为深入研究MITF-M基因调控狐狸被毛颜色的分子遗传机制奠定了理论基础。  相似文献   
910.
AIM: To evaluate the role of phosphatidylinositol 3-kinase/nuclear factor E2-related factor 2 (PI3K/Nrf2) signaling pathway in endotoxin-induced acute kidney injury in rabbits. METHODS: Healthy male New Zealand white rabbits were randomly divided into 5 groups: control group (group C), LPS group (group L), wortmannin+LPS group (group WL), wortmannin group (group W) and dimthyl sulfoxide (DMSO) group (group D). Wortmannin at dose of 0.6 mg/kg was injected via the auricular vein in groups W and WL, DMSO at concentration of 0.08 mL/kg was injected in group D, while normal saline (0.08 mL/kg) was injected in groups C and L. LPS at dose of 5 mg/kg was injected via the auricular vein in groups L and WL 30 min later, and equal volume of normal saline was injected in group C, D and W for control. The rabbits were sacrificed 6 h after LPS or normal saline administration. The kidneys were removed for microscopic examination and the determination of histological scores of kidney (HSK). The concentrations of blood urea nitrogen (BUN) and creatinine (Cr), urinary α1-microglobulin (α1-MG), MDA content, SOD activity, the mRNA expression of Nrf2 and HO-1, and the protein levels of total Akt, p-Akt, total Nrf2, p-Nrf2, nuclear Nrf2 and HO-1 in the renal tissues were also detected. RESULTS: Compared with groups C, D and W, the concentrations of BUN and Cr, urinary α1-MG concentration, MDA content and HSK were significantly increased, while SOD activity was significantly decreased (P<0.05). The mRNA expression of Nrf2 and HO-1, and the protein levels of p-Akt, total Nrf2, p-Nrf2, nuclear Nrf2 and HO-1 in the renal tissues were significantly increased in groups L and WL. No significant change among groups C, D and W was observed. Compared with group L, the concentrations of BUN and Cr, urinary α1-MG concentration, MDA content and HSK were significantly increased, while SOD activity, the mRNA expression of Nrf2 and HO-1, and the protein levels of p-Akt, total Nrf2, p-Nrf2, nuclear Nrf2 and HO-1 in the renal tissues were significantly decreased in group WL. CONCLUSION: Activation of PI3K/Nrf2 signaling pathway may be one of the regulatory mechanisms of the body adapting to the endotoxin-induced acute kidney injury in rabbits.  相似文献   
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