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41.
YANG Xiu-hong QIN Chuan△ CHEN Yun-xin ZHU Hua HUANG Lan LIU Ya-li MA Chun-mei ZHANG Lian-yuan YANG Fang 《园艺学报》2010,26(1):158-162
AIM: To investigate the expression of angiotensin-converting enzyme 2 (ACE2) in nephritic epithelium of primates. METHODS: The expression of ACE2 in Vero E6 cells was detected by the techniques of RT-PCR and immunocytochemistry (ICC) techniques. The distribution of ACE2 protein in kidney tissues of two Rhesus monkeys and two normal human cases was observed by immunohistochemistry (IHC) techniques. RESULTS: Vero E6 cells were found to express both ACE2 mRNA and protein. ACE2 protein was mainly located in epithelium of proximal tubules of Rhesus monkey and human kidney. CONCLUSION: The expression of ACE2 in epithelium of primate kidney may provide the condition for SARS-CoV entry, which may be one of the reasons for inducing renal damage in SARS patients. 相似文献
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小麦条锈病高光谱近地与高空遥感监测比较研究 总被引:10,自引:0,他引:10
小麦条锈病是我国小麦生产中的重要病害,对该病防治的关键是做好监测工作。本研究利用ASD手持野外光谱仪[ASD FieldSpec HandHeld FR(325~1 075 nm)]和热气球在近地与高空研究了发病小麦冠层的高光谱遥感数据特征,获得了近地和对应高空2个不同平台光谱数据。经比较分析,发现高空数据与近地数据之间存在明显而有规律的变异关系,即高空获得的光谱反射率在可见光谱区域明显大于近地获得的光谱反射率。进一步对差异最显著的绿峰580 nm和黄边610 nm处数据进行回归分析,获得了高空光谱反射率值与近地光谱反射率值之间的回归模型,为进一步研究利用高平台遥感监测小麦条锈病奠定了一定的理论基础。 相似文献
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CHEN Xiao-ling HUANG Shan-sheng LI Ying-min LI Wen-bin WANG Xin-liang WANG Qiu-hong 《园艺学报》2001,17(6):534-537
AIM: To observe the kinetic alteration of nitric oxide formation in the lungs in the development of pulmonary fibrosis in the rat. METHODS: The contents of hydroxyproline in the lungs, NO2-/NO3- (nitrite/nitrate) in out-flowing and in-flowing pulmonary blood (OPB, IPB) were assayed on the day 7, 14, 21, 30 and 70 after intratracheal administration of bleomycin A5 . The content of NO2-/NO3- in supernatants of culture of the alveolar macrophages (AMs) and the amount of iNOS positive stain cells in lung tissue section were also observed in the rat on 14th day after-bleomycin A5 administration. RESULTS: The content of lung hydroxyproline had no change on the 7th day, increased on the 14th day (P<0.05), increased significantly on the 21th day, 30th day and 70th day post-bleomycin A5 compared with control rats. On the 7th day and 14th day, the content of NO- 2 /NO3- increased in OPB and decreased in IPB (P<0.01). On the 21th day, the content of NO2-/NO3- abated in OPB (P>0.05) but still decreased in IPB (P<0.01). On the 30th day and the 70th day, the NO2-/NO3- level recovered both in OPB and IPB. AMs from rats on the 14th day post-bleomycin A5 showed significant elevation (P<0.01) in NO2-/NO3- level. The amount of iNOS positive stain cells increased in rats on the 14th day post-bleomycin A5. CONCLUSION: The amount of NO in the lungs was high in the initial phase of fibroproliferative reaction induced by bleomycin A5 ,and these might be associated with the enhanced ability of AMs to release NO and the increased amount of iNOS. 相似文献
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本试验旨在探索家蚕体适应桑叶营养物质变动的微观机制。首先检测老、嫩2种成熟度桑叶的水分、粗蛋白质、粗脂肪、可溶性糖、还原性糖、多糖、总黄酮、总多酚和1-脱氧野尻霉素(1-DNJ)含量,然后采用相对和绝对定量同位素标记(iTRAQ)技术分析由这2种桑叶饲喂3 d的5龄家蚕脂肪体蛋白质组表达谱,并对差异表达蛋白进行生物信息学分析。结果显示:嫩桑叶的粗蛋白质、粗脂肪、还原性糖、总黄酮、总多酚、1-DNJ含量极显著高于老桑叶(P<0.01)。iTRAQ定量分析共鉴定到家蚕脂肪体蛋白2 172个,2组间差异表达蛋白173个。相对于摄食老桑叶的家蚕,摄食嫩桑叶的家蚕脂肪体中上调表达蛋白为85个,下调表达蛋白为88个。对其中的111个差异表达蛋白[差异表达倍数(FC)>1.25或<0.80]的功能富集分析发现,GO和KEGG通路注释到这些蛋白主要参与物质代谢、运输和贮存,应激和免疫反应,机体发育等生物学过程。差异表达蛋白互作网络分析筛选到核糖体蛋白和神经前体细胞表达发育下调蛋白8(NEDD8)的网络中心性高。综上可知,桑叶成熟度显著影响其营养物质含量,引起摄食老、嫩桑叶家蚕脂肪体蛋... 相似文献
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ZHANG Qi-hao ZHENG Wei-wei GAO Li-lian LIU Xia DENG Xin-yan ZHANG Lei CHEN Xi-gu HUANG Ya-dong 《园艺学报》2010,26(11):2207-2211
AIM: To establish an optimal differentiated three-dimensional microenvironment formed by hanging drops for the high efficiency of hepatic differentiation from rat mesenchymal stem cells(rMSCs).METHODS: rMSCs were cultured in the hanging drops, which provided a three-dimensional microenvironment, for 21 days in the presence of hepatocyte growth factor(HGF, 20 μg/L). The expression of albumin(ALB), alpha-fetoprotein(AFP) and cytokeratin-18(CK-18) was detected by RT-PCR and immunofluorescence staining at 7th, 14th and 21st days. The secretion of albumin in the culture supernatants was measured by ELISA. RESULTS: rMSCs were aggregated in spheroid with a tubiform medium altitude in the center. In rMSCs cultured in the hanging drops with HGF, the expression of albumin, AFP and CK-18 was all detectable by RT-PCR and immunofluorescence staining at 7th day. The production of albumin in the cells cultured in the hanging drops with HGF was 50.25±5.32, 55.03±7.45 and 54.92±3.18(ng·dish-1·d-1) at 7th, 14th and 21st days, respectively, significantly higher than that in the cells in the plate cultivation with or without HGF induction at corresponding time points(P<0.01).CONCLUSION: In the presence of HGF, rMSCs are induced to differentiate into hepatocyte-like cells cultured in the hanging drops, where the three-dimensional spheroidal cultures are promising microenvironment for hepatic transdifferentiation of MSCs. 相似文献
50.
利用紫外吸收光谱法(UV-Vis)、红外光谱法(IR)及差示扫描量热法(DSC)等考察了七元瓜环(Q[7])与阿德福韦(PMEA)的相互作用.结果表明:Q[7]与PMEA相互作用形成包结比为1∶1的主-客体包合物,包结平衡常数为(2.81±0.04)x104L/mol;在0<pH<6范围内均能观察到主客体的相互作用,在... 相似文献