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141.
142.
在2 450 MHz频率的微波处理条件下,为了考察添加鲢鱼糜对小麦粉面团糊化的影响,将小麦粉、鲢鱼糜、NaCl和去离子水按比例混合制成鲢鱼糜面团,面团中鲢鱼糜含量分别为0%,10%,20%和30%(w/w,质量百分比),对样品面团中淀粉的介电特性和糊化特性进行研究。结果表明,对于相同尺寸的面团样品,添加鲢鱼糜可改善面团样品在电磁场中的加热均匀性。随着温度的升高,面团的介电常数和介电损失率分别在20~23和9~12内波动并呈下降趋势,微波的穿透深度因淀粉的糊化略有上升。淀粉的糊化速率随温度的升高而下降。降低样品中淀粉的含量,会使面团糊化活化能由113.54 kJ/mol下降至59.96 kJ/mol。 相似文献
143.
144.
农药残留超标已成为影响农产品质量安全的重要问题,迫切需要探寻开发灵敏、准确、可靠、便捷且适用性强的农药残留快速检测方法。免疫层析法是将抗原抗体特异性免疫反应和色谱层析分离技术相结合的一种快速检测方法,其中,基于胶体金标记的免疫层析技术以其便捷、成本低、可视化等优点而受到普遍欢迎。近年来随着量子点、时间分辨荧光微球、上转换发光纳米粒子等新型纳米标记材料的出现,免疫层析技术得到了广泛发展。文章从标记类型(非共价作用标记及共价作用标记)及标记材料(胶体金、纳米碳、量子点、上转换发光纳米粒子、磁性纳米颗粒、时间分辨荧光微球及荧光乳胶颗粒)等方面,综述了不同纳米材料标记的免疫层析技术及其在农药残留检测领域的研究及应用进展,可为深入开展农药残留免疫层析技术研究提供参考。 相似文献
145.
Hong-Xiu Diao Shuai Zhang Xue-Yuan Hu Wei Guan Li Luan Hai-Yu Liu Hong-Gang Fan 《Veterinary anaesthesia and analgesia》2017,44(1):114-120
Objective
To evaluate the behavior and some cardiopulmonary variables of dexmedetomidine–midazolam or dexmedetomidine–midazolam-butor-phanol in the silver fox (Vulpes vulpes).Study design
Blinded, randomized design.Animals
Sixteen adult silver foxes, aged 7–9 months, weighting 6.0–9.2 kg.Methods
Animals were randomly assigned to dexmedetomidine (50 μg kg?1) and midazolam (0.45 mg kg?1) (group DM) or to dexmedetomidine (30 μg kg?1), midazolam (0.45 mg kg?1) and butorphanol (0.25 mg kg?1) (group DMB), administered intramuscularly. Pulse rate (PR), respiratory rate (fR), noninvasive arterial pressures, oxygen saturation (SpO2), rectal temperature (T) and behavioral scores (posture, sedation, antinociception, jaw relaxation and auditory response) were measured at 5, 10, 20, 30, 40, 50 and 60 minutes after injection. Time from drug injection to recumbency with no response to stimuli (IT) and time from administration of atipamezole (0.2 mg kg?1) to standing with coordination (RT) were recorded. The occurrences of adverse events were recorded. Data were analyzed by two-tailed unpaired t-tests and Bonferroni post hoc tests. Significant differences were accepted at p<0.05.Results
There were no statistically significant differences between the groups for IT or RT. Arterial pressures were higher in DMB at each time point except at 5 minutes. PR was lower in DM at each time point except at 10 and 60 minutes. No significant difference was found between the groups for fR, SpO2 and T. The behavioral scores were significantly lower (lower quality immobilization) in DMB at 5,10 and 60 minutes.Conclusions and clinical relevance
IT and RT were not different between the groups. Both protocols provided immobilization for 30–40 minutes with excellent muscle relaxation and analgesia adequate for clinical examinations and some simple surgical procedures. 相似文献146.
《植物养料与土壤学杂志》2017,180(6):683-693
The purpose of this study was to use zero‐valent iron nanoparticles (nZVI) and cellulosic wastes to reduce bioavailability of lead (Pb) and cadmium (Cd), and to establish Persian maple seedlings (Acer velutinum Bioss.) in contaminated soil. One‐year‐old seedlings were planted in pots filled with unpolluted soil. Lead [Pb(NO3)2] and Cd [Cd(NO3)2] were added with concentrations of 0 (Control), 100 (Pb100), 200 (Pb200), and 300 (Pb300) mg kg−1 and 10 (Cd10), 20 (Cd20), and 30 (Cd30) mg kg−1. Cellulosic wastes were mixed with soil at the same time of planting [four levels: 0, 10 (W1), 20 (W2), 30 (W3) g 100 g−1 soil]. The nZVI was prepared by reducing Fe3+ to Fe0 and injected to pots [four levels: 0, 1 (N1), 2 (N2), and 3 (N3) mg kg−1]. Height, diameter, biomass, tolerance index of seedlings, bioavailability of heavy metals in soil, and removal efficiency of amendments were measured. The highest values of seedling characteristics were observed in N3. The highest removal efficiency of Pb (Pb100: 81.95%, Pb200: 75.5%, Pb300: 69.9%) and Cd (Cd10: 92%, Cd20: 73.7%, Cd30: 68.5%) was also observed in N3. The use of nZVI and cellulosic waste could be a proper approach for seedling establishment in forests contaminated with heavy metals. 相似文献
147.
148.
To explore the potential of a novel animal interferon formulation for controlled release, the yak interferon-alpha (IFN-α) glutathione S-transferase (GST) fusion protein was expressed in Escherichia coli (E. coli) and the purified recombinant IFN-α was encapsulated into solid lipid nanoparticles (SLN) by double emulsion solvent evaporation (w/o/w) method. The particle size and zeta potential of IFN-α-loaded SLN were 124.2 ± 10.2 nm and −11.2 ± 0.6 mV. The encapsulation efficiency of IFN-α and loading capacity of the SLN were 83.7 ± 4.5% and 1.73 ± 0.15%, respectively. In vitro release study and antiviral assay demonstrated that the IFN-α released from the SLN in a 16-day period exhibited antiviral activity in Madin-Darby bovine kidney (MDBK) cells against vesicular stomatitis virus (VSV), and showed a release pattern of an initial burst release followed by a sustained and slow release. Cytotoxicity assay in cell culture demonstrated that the SLN were not toxic. The results of this exploratory study suggest that the IFN-α-loaded SLN could be a useful formulation for controlled release in veterinary therapeutics. 相似文献
149.
为了研究不同外源激素组合对银狐繁殖力的影响,随机选择健康母银狐50只,分为4个试验组和1个对照组,每组10只。在母狐排卵的前10 d开始对4个试验组注射外源激素,每组注射两种激素(第1激素和第2激素),每组的第1激素和第2激素有所不同;对照组母狐按常规方式饲养管理。结果表明,试验1组(PMSG+HCG激素组)平均产仔数比对照组多1.3只/母,差异极显著(P<0.01);试验4组(FSH+LH激素组)平均产仔数比对照组多0.9只/母,差异显著(P<0.05);试验2组(三合激素+LRHA3激素组)、试验3组(LRHA3+LRHA3激素组)平均产仔数与对照组间无显著差异(P>0.05);试验1组与试验2、3组间差异显著(P<0.05),而与试验4组间差异不显著(P>0.05);试验2、3、4组间差异不显著(P>0.05)。通过性价比对比,PMSG+HCG激素组合的性价比(0.078)为最高;而另外3组激素组合的性价比均较低。综上所述,PMSG+HCG激素组合平均产仔数多、激素性价比高,应用效果显著。 相似文献
150.
纳米载铜蒙脱石对生长肥育猪生产性能 总被引:2,自引:1,他引:1
摘要:试验旨在研究日粮中添加纳米载铜蒙脱石对生长育肥猪生产性能及血液生化指标的影响。选取72头健康“杜×大×长”三元杂交断奶仔猪,随机分为3组,每组3个重复,每个重复8头(公母各半)。分别饲喂基础日粮(对照组)、基础日粮+20 mg/kg泰乐菌素+100 mg/kg磺胺二甲基嘧啶(SM2)(试验Ⅰ组)和基础日粮+1500 mg/kg纳米载铜蒙脱石(MMT-Cu)(试验Ⅱ组)。比较研究MMT-Cu和泰乐菌素+磺胺二甲基嘧啶对生长肥育猪生产性能及血液生化指标的影响。结果表明,与对照组和试验Ⅰ组相比,试验Ⅱ组料重比、血清ALB、SUN、Ch、TP含量极显著下降(P<0.01);血钙含量、GTP活性极显著提高(P<0.01);TP和GLU含量显著下降 (P<0.05)。因此,纳米载铜蒙脱石提高了生长肥育猪的料重比,并对血清中ALB 、Ca、GPT、SUN、TG、Ch、TP、GLU均产生不同程度的影响。 相似文献