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41.
Comparison of morphology, viability, and function between blood and milk neutrophils from peak lactating goats
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Sui Zhi Tian Chai Ju Chang Chih Chi Chiang Huo Cheng Peh Mu Chiou Huang Jai-Wei Lee Xin Zhao 《Canadian journal of veterinary research》2005,69(1):39-45
The morphological features of blood and milk neutrophils from peak lactating goats were compared using light microscopy, scanning electron microscopy and flow cytometry in order to investigate the cytological changes of neutrophils after migration into the mammary gland. The kinetics of reactive oxygen intermediates (ROI) generation and gelatinase release of blood and milk neutrophils, with or without stimulation of phorbol 12-myristate, 13-acetate ester (PMA), were used to characterize their responses to inflammatory stimuli. Neutrophils isolated from goat milk were highly segmented and contained multi-lobed nuclei. Ultrastructurally, milk neutrophils were more ruffled on the surface compared to blood neutrophils. Approximately 30% of milk neutrophils were undergoing cell death, either necrosis or apoptosis, in contrast to 8% of blood neutrophils. The ROI production of activated milk neutrophils peaked earlier than blood neutrophils, but the duration and the intensity were much less. Neutrophils from both sources augmented the release of gelatinase in response to PMA (1 ng/mL). However, the amount of gelatinase released from milk neutrophils was lower (P < 0.05) than that of blood neutrophils. In summary, more neutrophils become apoptotic and necrotic in the mammary gland, presumably due to spontaneous aging, the process of diapedesis, and the interaction with milk components. Milk neutrophils have impaired functionalities in comparison with blood neutrophils. The information is relevant when studying mammary gland immunity and related diseases, such as mastitis. 相似文献
42.
AIM:To investigate the effect of insulin on ox-LDL transferring the THP-1 cells to foam cells and influencing the LPL mRNA expression in THP-1 cells.METHODS:THP-1 cells were incubated with 50 mg/Lox-LDL and insulin at concentrations of 10 mU/L, 100 mU/L, 1 000 mU/L and 10 000 mU/L, respectively. The expression of LPL mRNA in cells was detected by RT-PCR. Lipoprotein lipase of THP-1 cells was presented by no-specific lipase staining. THP-1 cells were stained with oil red O. Accumulation of total cholesterol (TC) in THP-1 cells was determined with oxidase assay.RESULTS:In 100 mU/L、1 000 mU/L、10 000 mU/L insulin groups, LPL mRNA expression increased 2 times, the average cell perilength was longer, the percentage of positive oil red O staining cells was significant higher, the content of cholesterol in THP-1 cells was higher than in ox-LDL control (P<0.05).CONCLUSION:Insulin accelerates transferring of THP-1 cells to foam cell with exposed to ox-LDL because LPL mRNA expression increased in the cells. 相似文献
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‘三棱榄''橄榄果实香气成分分析 总被引:7,自引:1,他引:7
1 材料与方法选取广东优良鲜食橄榄品种‘三棱榄’,2001年12月6日采样,采用固相微萃取法(SPME)富集香气成分(鲜橄榄果肉于15℃下捣碎后取样1.0 g放入4 mL聚四氟乙烯硅橡胶垫密封螺口玻璃瓶中,插入100μm聚二甲基硅氧烷纤维头于室温25-30℃顶空取样2 h),用美国Finnigan TRACE GC-MS气相色谱-质谱联用仪进行分析。气相色谱柱为DB-1弹性毛细管柱30 m×0.25 mm,载气为He(99.99%),流速1.0mL/min。程序升温从40℃开始先保持10 min,后以2℃/min的升温速率升至150℃保持10 min。质谱条件:电子能量70 eV,离子源温度250℃,质量范围35-450 aum,不分流进样。2002年12月18日采样重复分析。 相似文献
45.
AIM:To investigate the effect of tea-polyphenols (TP) on the activation of NF-κB and the expression of TGF-β1 mRNA in THP-1 cells (a human acute monocytic leukemia cell line). METHODS:THP-1 cells were incubated with the different concentrations of TP, VLDL, LDL or ox-LDL. In the THP-1 cellls, the nuclear malposition rate of NF-κB was detected with immunohistochemistry technique, the positive index of the TGF-β1 mRNA expression was detected by hybridization in situ, and accumulation of total cholesterol (TC) in cells incubated with 0.4-40 μg/L TP was determined with oxidase assay. RESULTS:The nuclear malposition rate of NF-κB, the positive index of the TGF-β1 mRNA expression and TC in THP-1 cells incubated with 0.4-40 μg/L of TP were lower than those with 0 μg/L of TP in TP-V group, TP-L group and TP-O (P<0.05). The differences of these markers in THP-1 cells incubated with more than 40 μg/L TP in TP-V group, TP-L group and TP-O were not statistically significant, compared with TP-C group (P>0.05). CONCLUSION:TP inhibited the activation of NF-κB, the expression of TGF-β1 mRNA and the foam cell formation in the mono-macrophage. 相似文献
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47.
以红富士苹果果实为试材,在盛花后30d以内,分3次向幼果中引入EGTA和LaCl3,研究了两种钙的抑制剂对果实细胞超微结构和果实生长的影响。结果表明,EGTA主要是在盛花后20d以前影响果肉细胞形态建成,导致细胞扭曲变形;而La3+是在盛花后20d以后,细胞开始扭曲变形,盛花后10d,质体上开始出现淀粉粒,盛花后30d,质体上淀粉粒明显增多。两种抑制剂对幼果发育有不同程度的影响。LaCl3处理,对幼果发育有抑制作用,其中,花后20d处理,抑制效应最强。花后20dEGTA处理,对果实的横径生长有一定的促进作用,其它两次处理,则表现出对幼果生长的抑制效应。 相似文献
48.
SSR技术及其在果树上的应用 总被引:27,自引:4,他引:27
SSR(Simple sequence repeat)技术以其丰富的多态性、共显性遗传、重复性好和操作简便等优点日益受到重视,已成为植物遗传和育种研究中不可缺少的分子标记。对SSR技术的原理和特点作了简要的介绍,较详细地分析了如何获得SSR引物,特别是综述了果树上SSR引物的研究现状,同时将其与其它几种主要的分子标记进行了比较分析,认为SSR标记检测的位点多态性水平明显高于RFLP,而且重复性优于RAPD;着重介绍了SSR技术在果树种质资源和构建果树遗传图谱及基因定位等研究中的应用现状;指出SSR技术将在果树科研上起到重要的作用。 相似文献
49.
入世后我国甜樱桃面临的机遇与挑战及发展对策 总被引:5,自引:0,他引:5
甜樱桃作为一种早熟、优质、保健果品,而且种植效益较高,在国内国际都正处于发展时期。根据世界甜樱桃生产和贸易情况,指出了我国在甜樱桃科学技术与生产上与世界先进甜樱桃生产国的差距,分析了我国加入WTO之后,我国甜樱桃面临的机遇和挑战,并且机遇大于挑战。如果有适当的科技投入,我国甜樱桃产业将可克服现在科技滞后的状态,发挥我国劳动力低廉和国土辽阔的优势,迅速扩大其生产总量,提高品质,扩大出口,增加农民的收入,2015年可望形成32.4~43.2亿元的社会总产值。 相似文献
50.