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81.
棘孢木霉菌剂对黄瓜生理特性及产质量的影响   总被引:1,自引:0,他引:1  
为改善黄瓜生理特性,保证其高产栽培,利用苗期和成株期盆栽试验,以无菌水为对照,分别施入10~3、10~4、10~5、10~6和10~7 cfu/g棘孢木霉(Trichoderma asperellum)菌剂,测定不同菌剂施用量后的黄瓜幼苗形态建成、生理指标、质量和产量性状。结果表明:棘孢木霉菌剂不同施用量均能有效提高幼苗株高、茎粗、叶面积、全株鲜重、全株干重、根冠比和壮苗指数,其中10~6 cfu/g棘孢木霉菌剂处理对黄瓜幼苗形态建成和物质积累的促进效果最好;棘孢木霉菌剂不同施用量均能改善黄瓜幼苗的生理特性,其中10~6 cfu/g棘孢木霉菌剂处理对黄瓜幼苗叶片叶绿素含量、根系活力、硝态氮含量、硝酸还原酶活性、可溶性糖含量和可溶性蛋白含量的促进效果最好;同时,棘孢木霉菌剂不同施用量均能促进黄瓜品质和产量形成,其中10~6 cfu/g棘孢木霉菌剂处理对黄瓜品质和产量促进效果最好,黄瓜果实可溶性糖、维生素C、可溶性蛋白、可溶性固形物含量和果实产量分别比CK提高了78.43%、31.55%、38.47%、8.63%和26.20%。综上,棘孢木霉菌剂通过改善黄瓜幼苗生理特性,促进幼苗生长,提高了黄瓜产量和品质性状,以10~6 cfu/g棘孢木霉菌剂应用效果最好,研究成果可为木霉菌剂的开发利用和黄瓜的优质栽培提供技术支撑。  相似文献   
82.
为寻求准确的鸡舍氨气浓度预测方法,构建基于双阶段注意力机制和长短时记忆神经网络(Long shortterm memory,LSTM)的鸡舍氨气浓度预测模型,将该模型应用于山东省商河县某蛋鸡养殖场,采集二氧化碳(CO_2)、氧气(O_2)和氨气(NH_3)的体积分数,细颗粒物(PM_(2.5))质量浓度,温度,相对湿度时间序列数据对模型进行验证,并与支持向量回归(Support vector regression,SVR)、人工神经网络(Artificial neural network,ANN)模型和无注意力机制的LSTM模型对比研究。结果表明:1)不同时间窗口T下NH_3体积分数预测精度不同。T∈{2,3,4,8}时,均方根误差(Root mean square error,RMSE)分别为0.433 4,0.394 8,0.379 9和0.405 1μL/L,平均绝对误差(Mean absolute error,MAE)分别为0.267 4,0.262 9,0.228 9和0.272 4μL/L;2)基于双阶段注意力机制和LSTM的鸡舍NH_3浓度预测模型在RMSE和MAE评价指标框架下优于SVR、ANN和无注意力机制的LSTM模型。基于双阶段注意机制和LSTM的模型能较好地对鸡舍氨气浓度进行预测,可为鸡舍氨气浓度预测及调控提供技术支持。  相似文献   
83.
旨在分析环境低温对H9N2亚型禽流感病毒感染小鼠致病性的影响。选用120只6~8周龄,雄性SPF BALB/c小鼠,随机分为4组:无感染常温组(PBS处理,(20±2)℃)、无感染低温组(PBS处理,(10±2)℃)、H9N2病毒感染常温组(H9N2处理,(20±2)℃)、H9N2病毒感染低温组(H9N2处理,(10±2)℃)。在感染后观察感染小鼠发病14 d内的临床症状、存活率,肺脏病变程度、肺部细胞因子含量的动态变化以及肺脏病毒载量。结果表明:1)与H9N2病毒感染常温组小鼠相比,环境低温处理的H9N2病毒感染小鼠临床症状明显加重,其中体重明显降低,但差异不显著(P>0.05),存活率由95%降为67%,肺水肿程度和肺组织病变程度更加严重;2)H9N2病毒感染低温组与H9N2病毒感染常温组相比,肺脏TNF-a和IL-1β含量无显著差异,但均显著高于2个无感染组(P<0.01);3)H9N2病毒感染低温组与H9N2病毒感染常温组相比,肺组织病毒载量显著增加(P<0.01)。综上,环境低温明显增加了H9N2亚型流感病毒对小鼠的致病性,为进一步揭示环境低温与流感病毒感染之间的关系,以及采取有效的预防措施提供数据基础。  相似文献   
84.
褐菖鲉的耗氧率与温度、盐度和体重的关系   总被引:2,自引:0,他引:2  
本文就体重、温度、盐度对褐菖鲉耗氧率的影响进行了初步研究.结果表明,褐菖鲉的耗氧量和耗氧率与体重(w)之间的关系可用幂函数Q=awb表示,其中,耗氧量随体重的增加而升高,耗氧率随体重的增加而降低.温度为11℃~20℃的范围内,褐菖鲉的耗氧率随温度的升高而升高,在温度为20℃时耗氧率达到最高值,超过这一温度耗氧率开始降低.盐度对其耗氧率的影响表现出低盐和高盐条件下耗氧率高的现象.  相似文献   
85.
中华鲟小水体养殖试验初报   总被引:4,自引:0,他引:4  
在7.2m^3水泥池中,采和人工配制饲料对中华鲟(Acipenser sinensis)进行养殖试验,通过4个阶段180d的养殖,鱼尾均增重1817.5g,日均增重分别为8.5,8.9,9.2,12.3,饲料系数为1.96,2.12,2.33,2.21。中华鲟在水水温处于8-29,1℃时均可摄食生长,利用人工配制养殖中华鲟的前景乐观。  相似文献   
86.
丽江猪是近年在云南丽江新发现的猪种遗传资源,笔者对丽江猪的体型外貌、体尺、胴体组成及肉质性状等种质特性进行测定。结果:丽江猪公、母猪体重分别为(60.71±4.93) kg和(54.11±12.88) kg,体高分别为(65.72±6.11) cm和(64.66±6.10) cm,体长分别为(105.64±9.61) cm和(102.18±10.51) cm,眼肌面积分别为(24.13±6.08) cm2和(23.62±6.16) cm2,瘦肉率分别为(40.09±3.17)%和(41.71±5.05)%,失水率(19.50±5.03)%,粗脂肪(15.71±4.68)%,pH(6.18±0.13),大理石纹(3.6±0.57)。丽江猪肉质各项指标均符合优质肉范畴,属于肉脂兼用型猪种,且含有丰富的脂肪酸,具有较高食用价值。  相似文献   
87.
为阐明洋山港建设运营期间对其所在海域产生的环境影响,在对2012年洋山港海域水体中溶解性重金属及石油烃进行周年监测的基础上,对洋山港海域重金属污染现状及特征进行了分析和评价。结果表明,洋山港海域主要重金属污染物为Hg,其余污染物依次为Cu、Pb和Zn;通过聚类分析将全年污染时段分为上半年(2012年1至5月)和下半年(2012年6至12月)两个阶段,时间分布及灰色聚类评价显示较严重的污染情况主要集中出现在上半年,空间分布显示小洋山码头沿岸及大洋山岛东南一带出现污染物高值区。鉴于洋山港正处于运营与建设同时进行的特殊阶段,需及时监测控制港区的污染物含量,本文提出采用GM(1,1)改进模型中发展系数的概念,深入研究污染物的变化趋势及规律。结果表明,监测海域各重金属污染物中Hg、Cr和Cd较难消除,应重视加强其防治措施。  相似文献   
88.
AIM: To synthesize a safe, efficient and targeted nanoparticulate carrier for siRNA delivery to pancreatic cancer cells. METHODS: Iron oxide nanocrystal with carboxylic acid group-polyethyleneimine (IONP-PEI) was synthesized and investigated as a nonviral carrier of siRNA to the pancreatic cells. The size, surface and charge using zeta potential were characterized. The perfect charge ratio between amino groups of IONP-PEI and phosphate groups of siRNA (N/P) was determined by the transfection efficiency detection, gel retardation assay and MTS assay. An antibody-directed nonviral vector, scFvCD44v6-IONP-PEI nanoparticle attaching to the cancer-associated CD44v6 single-chain variable fragment, was constructed as a cancer-targeting nanocarrier for siRNA delivery. Prussian blue staining and immunofluorescent staining were performed to detect the distribution of scFvCD44v6-IONP-PEI/siRNA complexes in the cells. The transfection efficiency, fluorescence intensity and the expression of KRAS at mRNA and protein levels in the cells transfected by IONP-PEI/siRNA and scFvCD44v6-IONP-PEI/siRNA were detected by flow cytometry, fluorescence microscopy, real-time PCR and Western blotting, respectively. RESULTS:The mass ratio of IONP to PEI was 0.75. The suitable ratio of N/P was 20. The averaged size and surface zeta potential of IONP-PEI/siRNA in deionized water were (51.3±2.2)nm (diameter) and (21.73±8.07)mV,respectively. Red fluorescence was seen in both targeting and nontargeting groups, which clearly revealed the intracellular distribution of siRNA and delivery agents. Transfection efficiencies in targeting and nontargeting groups were (89.75±1.81)% and (59.87±4.52)%, respectively. Down-regulation of the KRAS mRNA in Panc-1 cells transfected with siKRAS by scFvCD44v6-IONP-PEI and IONP-PEI was up to (34.02± 6.15)% and (51.09±6.70)%, respectively. The protein level of KRAS was lower in targeting group than that in nontargeting group. CONCLUSION:scFvCD44v6-IONP-PEI is a safe and efficient nanoparticulate carrier for gene delivery. It is more effective to transfer siRNA into the cells and mediate gene silencing effect in vitro than the nontargeting group.  相似文献   
89.
AIM:To investigate the promoting role of Transwell contact co-culture system in the growth and differentiation of single-dissociated induced pluripotent stem cells (iPSCs). METHODS:Bovine corneal endothelial cells (CECs) at passage 1~2 (P1~2) were seeded on the underside of Transwell inserts placed into culture plates and were cultured in 37 ℃ and 5% CO2 for 8 h. Accutase digestion and 40 μm filter process disaggregated colony-aggregated iPSCs into single-dissociated iPSCs, and the cells were seeded on the inside of Transwell inserts with CECs in medium of mTeSR1 for 3 d and then in low-glucose DMEM supplemented with 10% FBS for 2 weeks. The characteristics and differentiation markers were evaluated by real-time fluorescence quantitative polymerase chain reaction (qPCR), immunofluorescence staining, live & dead cell staining and alkaline phosphatase (ALP) staining. The group of iPSCs cultured in conventional medium was used as control group 1. The group of single-dissociated iPSCs co-cultured with CECs was set as experimental group, while single-dissociated iPSCs without co-culture were as control group 2. RESULTS:The bovine CECs showed typical hexagonal cobblestone shape. iPSCs showed colony-like growth, while became single-dissociated cells after Transwell contact co-culture with bovine CECs for 3 d. The single-dissociated iPSCs positively expressed the undifferentiated markers, Nanog and Oct4. The mRNA expression levels of Nanog, Oct4 and Sox2 between experimental group and control group 1 were both positive and had no statistical significance difference (P>0.05). The dead cells in experimental group decreased significantly, and there was statistically significant difference compared to control group 2 (P<0.01). After 14 d of induced differentiation co-culture, the single-dissociated iPSCs showed rather uniform polygonal morphology, increased dimension and no obvious colony existence. Negative ALP staining, positive immunofluorescence staining for ZO-1, AQP1 and CD31, and negative for CD34 and CD133 were also observed. The results of qPCR showed that the mRNA expression of Oct4, Nanog and Sox2 significantly decreased, and had statistically significant difference compared with control group 1 (P<0.01). CONCLUSION:When co-cultured with bovine CECs, iPSCs morphologically changed to endothelial-like cells and expressed some markers of CECs. Transwell contact co-culture system not only enhances the growth of single-dissociated iPSCs, but also promotes their differentiation.  相似文献   
90.
2011—2013年,山西省蚕业科学研究院对北方蚕区3个单位7个桑品种进行了鉴定。田间调查和实验室鉴定结果表明,7个参鉴桑品种生长势强、产叶量高,品质特性良好,在形态特征和生物学特性方面与对照存在不同程度的差异,而昌盛、9330两个品种的表现比较突出。  相似文献   
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