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71.
旨在揭示大肠埃希菌内毒素(ET)对大鼠小肠黏膜的结构、绒毛长度、上皮内淋巴细胞(IEL)的数量和分布的影响,并探讨多价阳离子A(CA)对上述指标的保护效应。选用72只140g~150g SPF级SD大鼠随机分为3组,即对照组、ET组和CA保护组,经相应处理后分别在3、4、8、12h采集十二指肠、空肠组织作为检测样本,制备病理组织切片,HE染色并利用图像分析系统进行分析。ET组十二指肠和空肠绒毛长度在3、4、8、12h均显著低于对照组和CA保护组(P0.01),ET组十二指肠、空肠IEL数量在3、4、8、12h均显著低于对照组(P0.01);CA保护组十二指肠和空肠IEL数量在4、8、12h均显著高于ET组(P0.01)。结果显示,ET在不同程度上能够破坏小肠黏膜的正常组织结构,降低小肠绒毛长度,减少IEL的数量,从而影响小肠正常的吸收和免疫功能,而CA则能明显降低ET所导致的毒性作用,发挥其保护效应。 相似文献
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本文着重分析了当前我国图书出版发行环境中出现的一些新的变化、新的特点和新的问题,并提出了在图书馆采访工作中,针对这些问题可采取相应的措施。 相似文献
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YAN Xiang-min ZHANG Jin-shan LI Hong-bo LI Na DU Wei ZHOU Zhen-yong ZHANG Yang 《中国畜牧兽医》2015,42(11):2954-2960
In this research,12 heads of 28 to 30 months (low months age group) and 8 heads of 32 to 34 months (high months age group) Xinjiang Brown cattle steers which fed in the same mode of nutrition were chose for the slaughter test,in which the carcass traits,nutrient composition and some edible quality index were measured and comparative analyzed,a research which through comparative analysis the carcass traits and meat quality of nutritional components of different months of Xinjiang Brown cattle steers was carried out.The results indicated that the marbling,carcass grade,fat,meat color of high months age group were better than that of low months age group,the traits of the low months age group on fat color,moisture,protein,cooking loss and shear force value were better than that of high months age group,and there were significant difference on the traits of fat and meat color L* between the two groups (P<0.05),while the differences of other traits between them were not significant (P>0.05);As high-grade beef,in addition to the traits of meat color and pH value of the chunk roll,tenderloin and striploin,each site of the meat traits on the fat,protein,moisture,cooking loss,shear force value indicators were all better than other parts,and showed the best of nutritional value and edible quality.28 to 34 months of Xinjiang Brown cattle steers could produce high-grade beef,the meat could be used as the raw materials of steak and boiled beef. 相似文献
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光辐射染色木材的变色规律及化学组分结构的变化 总被引:1,自引:0,他引:1
以I-214杨木染色单板为试材、氙光作为辐射光源,考察其在100h光照过程中表面颜色的变化规律;依据红外光谱图的谱峰位置和谱峰相对吸收强度,分析和确定光变色过程中染色杨木木材的化学组分。结果表明:染色杨木木材受光辐射易发生变色,其中酸性蓝染色单板的明度指数L*和色品指数b*变化显著,其光变色度显著大于酸性大红GR染色单板;若以波数1510cm-1为基准,非共轭羰基C=O振动的吸收峰(1738cm-1)吸收强度显著增强;共轭羰基C=O伸缩振动的吸收峰(1650cm-1)吸收强度有所增强;芳香环骨架C-C振动的吸收峰(1510cm-1)吸收强度明显减弱;C-O-H振动的吸收峰(1160~1052cm-1)吸收强度有所减弱。 相似文献
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AIM: To observe the therapeutic effect of Jiedu-Qingfei mixture on Mycoplasma pneumoniae (MP)-infected rat lung tissues and to explore its mechanism. METHODS: SD rats (n=40) were randomly divided into 4 groups:blank control group, model group, Jiedu-Qingfei group and positive control group, with 10 rats in each group. The rats in experimental groups were slowly dripped with 1×109 CFU/L MP solution into their nostrils for 4 d. One rat in each group was sacrificed for MP nucleic acid detection at the second day after inoculation, and the other rats were given gavage therapy. The rats in blank control group and model group were intragastrically given the same volume of normal saline, the rats in Jiedu-Qingfei group were given 8 mL/kg Jiedu-Qingfei mixture daily for 4 weeks, and the rats in psoitive control group were given dexmethasone sodium phosphate (0.5 mg·kg-1·d-1). After the experiment, the rats were killed. The serum and bronchoalveolar lavage fluid (BALF) were collected for detecting the levels of interleukin-12 (IL-12), IL-13 and TNF-α by ELISA. The right lung tissues were used for pathological observation and HE staining, while the left lung tissues were used to detect the expression of NF-κB p50, I-κBα and p38 mitogen-activated protein kinase (p38 MAPK) at mRNA and protein levels. RESULTS: The results of MP nucleic acid detection showed that all the rats except blank control group were MP nucleic acid positive, indicating that the rat model of MP infection was successfully established. On the 1st day of the treatment, the pathological scores of the lung tissues in model group and Jiedu-Qingfei group were significantly higher than those in blank control group (P<0.05). After treatment, the pathological scores of the lung tissues in mo-del group were significantly higher than those in blank control group and Jiedu-Qingfei group. The levels of IL-12 in the serum and BALF in model group were significantly lower than those in blank control group after MP infection (P<0.05), while those after treatment with Jiedu-Qingfei mixture were significantly higher than those in model group (P<0.05). The levels of IL-13 and TNF-α in the serum and BALF of MP-infected rats were increased significantly, while those after treatment with Jiedu-Qingfei mixture were significantly lower than those in model group (P<0.05). The mRNA expression levels of NF-κB p50 and p38 MAPK in model group were increased significantly (P<0.01). After treatment, the mRNA expression levels of NF-κB p50 and p38 MAPK were decreased significantly compared with model group (P<0.01). The mRNA expression level of I-κBα in model group was significantly lower than that in control group. After treatment, the mRNA expression of I-κBα in Jiedu-Qingfei group was significantly higher than that in model group (P<0.05). The protein levels of NF-κB p50 and p38 MAPK in the lung tissues of model group were significantly higher than those of blank control group. After treatment, the protein expression of NF-κB p50 and p38 MAPK was decreased significantly. The protein level of I-κBα in model group was significantly lower than that in blank control group, and after treatment with Jiedu-Qingfei mixture, the protein expression level of I-κBα was increased significantly (P<0.05). CONCLUSION: Jiedu-Qingfei mixture may attenuate lung tissue inflammation caused by MP through NF-κB and p38 MAPK pathways. 相似文献