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排序方式: 共有3547条查询结果,搜索用时 15 毫秒
971.
972.
973.
AIM: To determine whether interleukin 4 and interleukin 4 receptor α chain are associated with allergic asthma in children and to study the impact of such polymorphism upon plasma IgE.METHODS: Two polymorphism sites of IL-4 and IL-4R were studied by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).RESULTS: (1)The results showed that the IL-4 promoter -589 was not associated with children allergic asthma, however, the IL-4R α chain 576RR genotype and R allele were significantly increased in the subjects with asthma in children compared with age-matched control subjects (χ2=11.84, P<0.01; χ2=13.03, P<0.01). The IL-4R α chain 576RR genotype was associated with higher plasma IgE. CONCLUSION: These date suggest that the IL-4R α chain R576 is a risk factor of allergic asthma in children in Chinese, and is also related with higher plasma IgE level. 相似文献
974.
TAKESHI FUKAO SHOJI IDA MARY E. RUMPHO ROBERT A. KENNEDY YUJI YAMASUE 《Weed Biology and Management》2003,3(1):15-20
Gene expression was compared under favorable germination conditions between dormant and non-dormant seeds of rice paddy Echinochloa weeds and a domesticated Echinochloa species lacking dormancy. Two dormancy-specific cDNAs, Ecd1 and Ecd2 , were identified by differential display. Northern blot analysis revealed that these genes were more strongly expressed in dormant seeds than in non-dormant seeds. A database search for the Ecd1 sequence revealed no significant homology with any known proteins, but the Ecd2 sequence was highly homologous with the α-chain of mitochondrial H+ -transporting adenosine triphosphate (ATP) synthase in rice ( Oryza sativa L.). These findings indicate that the gene encoding the enzyme associated with conventional aerobic respiration is more abundantly transcribed in dormant seeds. The results reported in the present study suggest that dormant seeds of paddy Echinochloa weeds, which appear during the period when paddy soil becomes aerobic by drainage, may maintain viability primarily by efficient conventional aerobic respiration, including ATP synthesis catalyzed by the mitochondrial H+ -transporting ATP synthase. 相似文献
975.
鸡柔嫩艾美尔球虫ZJ株3-1E基因的原核表达及鉴定 总被引:1,自引:0,他引:1
本实验对E.tenellaZJ株的3-1E基因进行了克隆和表达。根据已报道的柔嫩艾美尔球虫3-1E基因序列设计引物,以孢子化卵囊总RNA为模板,用RT—PCR方法扩增得到一条特异片段,将扩增产物克隆至pUCM—T,转化感受态菌DH5仅,经酶切鉴定获得阳性重组质粒并对其进行测序。测序结果与参考序列比较,核苷酸同源性为99.5%。然后将重组质粒和表达载体pET-30a分别以EcoRⅠ、SalⅠ酶切后构建重组表达载体pET-30a-3—1E,并将其转化入大肠杆菌BL21中,提取质粒经酶切和PCR鉴定正确后,用IPTG诱导表达。表达产物经SDS—PAGE和Westernblot检测显示,3-1E基因在大肠杆菌中成功表达;融合蛋白的分子量约为27ku,诱导6h的蛋白表达量可达到47、024%。 相似文献
976.
Baldwyn Torto Yousif O
H Assad Peter G
N Njagi Ahmed Hassanali 《Pest management science》1999,55(5):570-571
Bioassays have shown that sand freshly contaminated by ovipositing females of the gregarious desert locust Schistocerca gregaria (Forskal) is more effective in inducing further oviposition from conspecifics than contaminated sand stored for three or six months, which contrasts with results obtained previously with Locusta migratoria (Reiche & Farmaire). The activity of contaminated sand correlated with the levels of three unsaturated aliphatic ketones, (Z)-6-octen-2-one, (E,E)-3,5-octadien-2-one and its geometric isomer (E,Z)-3,5-octadien-2-one present in the volatile emissions from the sand. 相似文献
977.
为了探究茯苓配方(茯苓、山楂、黄大茶)浸膏对高脂饮食小鼠肥胖及脂质沉积的影响,将C57/BL6N小鼠随机分为对照组,模型组,奥利司他药物对照组,茯苓配方(Poria cocos Wolf formula,PWF)浸膏低、高剂量组。除对照组给予低脂饲料,其他组均以高脂饲料喂养12周。每周记录小鼠的体重、能量摄入。给药结束后,计算各组小鼠Lee’s指数、脏器系数,采用苏木精-伊红(hematoxylin-eosin,HE)染色法观察各组小鼠肝细胞与脂肪细胞形态变化,全自动生化仪测定各组小鼠血清中TG、TC、HDL-C、LDL-C、AST及ALT水平变化。结果显示,与对照组相比,模型组小鼠体重、Lee’s指数、脏器系数、TG、TC、LDL-C、AST及ALT水平均显著升高(P<0.01或P<0.001),肝脏脂滴数量与脂肪细胞直径增加;与模型组相比,茯苓配方浸膏高剂量组小鼠体重、Lee’s指数和脏器系数均显著降低(P<0.05或P<0.01),低剂量组小鼠体重、Lee’s指数和脏器系数均没有显著变化,茯苓配方浸膏高剂量组小鼠肝脏脂滴数量与脂肪细胞直径减少,TG、TC、... 相似文献
978.
Antioxidation responses of maize roots and leaves to water deficit and rewatering under partial root-zone irrigation (PRI) were investigated using a pot system. Plants were cultured using three irrigation methods, i.e. conventional irrigation (CI), alternate PRI (APRI) and fixed PRI (FPRI) with three different water regimes including W1 (70% field capacity, FC), W2 (50% FC) and W3 (35% FC). Compared to CI, root peroxidases (POD) activity was enhanced in the irrigated root zone of FPRI and both root zones of APRI during mild water deficit. After rewatering, POD activity was increased in the dry root zone under FPRI but reduced in the roots under APRI. Roots in the dry zone and leaves under FPRI remained high superoxide dismutase (SOD) activity after rewatering. In contrast, SOD activity decreased in the roots and leaves under CI and APRI. Malondialdehyde (MDA) contents were increased in leaves and two sub-roots under FPRI during water deficit and remained higher after rewatering compared to those under CI and APRI. MDA contents in the tissues under APRI showed similar levels to those under CI. Compared to CI, APRI showed the same biomass production, achieving significantly higher water use efficiency under mild water deficit. The results suggested that plants under APRI experienced less oxidative stress or damage induced by water deficit. 相似文献
979.
Paola Gonzalez Audino Hector Masuh Susana A. de Licastro Claudia Vassena María I. Picollo Eduardo Zerba 《Pest management science》1997,49(4):339-343
A series of methyl esters of N-substituted (Z)- and (E)-maleamic acids were synthesized and their effect on food intake measured on fifth-instar nymphs of Triatoma infestans. Suppression of food intake was found only for the (Z)-isomers. The initial reaction rate of the synthesized compounds with glutathione (GSH) was calculated from the reaction in vitro of the (Z)-isomers. No reaction was observed with the (E)-isomers. Good correlation between the suppression of food intake, measured by its ED50 (effective dose that inhibited feeding of 50% of the population) and the initial reaction rate with GSH and the hydrophobic parameter π, was found. © of SCI. 相似文献
980.