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排序方式: 共有852条查询结果,搜索用时 15 毫秒
1.
Mona Saleh Ehab Essawy Mohamed Shaalan Shaaban Osman Fatma Ahmed Mansour El-Matbouli 《Marine drugs》2022,20(7)
Marine bio-sourced chitosan nanoparticles (CSNP) are antimicrobial and immunomodulatory agents beneficial for fish medicine. Herein, dietary CSNP was investigated for the amelioration of the systemic inflammatory responses of an induced fish model. One hundred and forty-four rainbow trout were assigned to one pathogen-free and non-supplemented group (negative control), and three challenged groups: non-supplemented (positive control), CSNP-preventive, and CSNP-therapeutic. After a feeding experiment extended for 21 days, the organosomatic indices (OSI) and molecular aspects were assessed. After a challenge experiment extended for further 28 days, CSNP-therapeutic intervention was assessed on fish survival and systemic inflammatory responses on pathology, histo-morphology, and molecular aspects. With CSNP administration, OSI nonsignificantly decreased and the relative expression of targeted inflammatory-mediator genes was significantly increased. The CSNP-therapeutic fish showed an RPS of 80% as compared to the positive control group, and CSNP-therapeutic administration retained the highest gene expression augmentation up to 28 days after the challenge. Notably, the splenic reticulin fibers framework of the CSNP-therapeutic group retained the highest integrity among the groups during the infection. After recovery, reticulin fibers density in the CSNP-therapeutic samples was significantly higher than in the negative control group, which indicates high innate immunity. Thus, CSNP showed promising biotherapeutic features enhancing fish resistance against infections. 相似文献
2.
银染mRNA差异显示方法在致突变实验中的初步应用 总被引:2,自引:0,他引:2
为建立在药物致突变研究中应用银染 m RNA差异显示的方法 ,试验提取未经过 /经过环磷酰胺处理的 Balb/c小鼠肝组织的总 RNA ,并以此为模板 ,采用 d T1 2 CG、d T1 2 AG、d T1 2 GG为锚定引物 ,通过反转录、差异显示 PCR反应 ,以 6 %变性聚丙烯酰胺凝胶电泳分离差异条带 ,回收后将其再扩增。结果表明 ,RNA投入量为 3μg、镁离子浓度为 1.5~ 2 .0 mm ol/L、退火温度为 4 0℃时 ,扩增的片段条带清晰、背景低 ,差异条带明显 ,再扩增条带单一。银染 m RNA差异显示技术可成功应用于药物致突变的研究。 相似文献
3.
纳米载铜蒙脱石对生长肥育猪生产性能 总被引:1,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
4.
In evaluating radiographs of the limb joints and head, students encounter difficulty where superimposition occurs. By replacing calcium with silver salts in the bone, enhanced radiopacity can be produced. In this study, silver impregnation was used to increase the radiopacity of individual carpal and tarsal bones, selected bones of the skull and the sinuses, and guttural pouch of the horse. This provides an interpretation aid for teaching radiographic anatomy of these regions. 相似文献
5.
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
6.
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
7.
8.
Katarzyna Ognik Ewelina Cholewiska Jerzy Jukiewicz Zenon Zduczyk Krzysztof Tutaj Radosaw Szlzak 《Journal of animal physiology and animal nutrition》2019,103(2):675-686
The aim of the study was to evaluate the effects of a diet containing different levels of Cu in two different chemical forms (carbonate and nanoparticles) on redox reactions and epigenetic changes in a rat model. For 4 weeks, five experimental groups (eight rats in each) were fed diets with two dosages of added Cu (standard—6.5 mg/kg or half of the standard dosage—3.25 mg/kg, and as a negative control no additional Cu in the mineral mixture) in two forms (standard—CuCO3 and copper nanoparticles). Addition of Cu nanoparticles resulted in higher Cp (ceruloplasmin) activity and LOOH (lipid peroxides) and MDA (malondialdehyde) content, as well as decrease the CAT (catalase) activity and level of PC (protein carbonyl), 3‐NT (3‐nitrotyrosine), 8‐OHdG (8‐hydroxydeoxyguanosine), GSH + GSSG (total glutathione) and DNA methylation. Reducing the dose of copper resulted in a decrease in the level of LOOH and GSH + GSSG as well as CAT activity, but increased the level of PC and methylated DNA. Based on these evidence, we concluded that addition of copper nanoparticles in the diet reduces protein oxidation and nitration as well as DNA oxidation and methylation. Lowering the level of Cu in the diet increases the oxidation of proteins and DNA methylation. 相似文献
9.
依据GB 5009.44—2016《食品安全国家标准 食品中氯化物的测定》,对特殊医学用途婴儿配方食品中氯的检测方法适用性展开研究。结果表明:采用GB 5009.44—2016第三法(银量法)检测特殊医学用途婴儿配方食品中乳蛋白部分水解配方、乳蛋白深度水解配方、氨基酸配方得到的样品加标回收率分别为95%~108%、98%~125%、100%~106%,相对标准偏差为12.7%~32.9%;采用GB 5009.44—2016第一法(电位滴定法)得到的检测结果低于第三法检测结果。 相似文献
10.
研究美洲大蠊(俗称蟑螂)提取物CⅡ-3纳米粒对免疫力低下小鼠免疫功能的改善作用。制备美洲大蠊提取物CⅡ-3纳米粒,并建立免疫功能低下小鼠模型,将小鼠随机分为正常对照组和模型组(灌胃生理盐水,0.2mL/10g),辅料组(灌胃空白纳米粒,40mg/kg,0.2mL/10g),阳性对照组(灌胃左旋咪唑,40mg/kg,0.2mL/10g),CⅡ-3组(灌胃美洲大蠊提取物CⅡ-3,40mg/kg,0.2mL/10g),CⅡ-3纳米粒5个剂量组(灌胃美洲大蠊提取物CⅡ-3纳米粒10、20、40、80、160mg/kg,0.2mL/10g),各组连续给药15d后,检测小鼠外周血白细胞、红细胞、血小板;脏器指数;巨噬细胞吞噬功能;血清中免疫球蛋白IgG、IgM的含量。研究结果显示,CⅡ-3纳米粒各剂量组均可以显著提高免疫低下小鼠的白细胞数量(P<0.05);能显著提高免疫力低下小鼠的肝脏、脾脏和胸腺指数(P<0.01);可显著提高其巨噬细胞吞噬能力(P<0.05)和免疫力低下小鼠血清中IgG、IgM的含量(P<0.01),说明CⅡ-3纳米粒有改善免疫力低下小鼠免疫功能的作用。 相似文献