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991.
WU Bin CAI Xiao-chang ZENG Yao-ying SHI Jun WANG Tong ZHAO Jing-xian HUANG Xiu-yan 《园艺学报》2005,21(5):931-935
AIM: To explore the inhibitory effect of oxymatrine (OMT) on the allergic contact dermatitis (ACD) stimulated by dinitrofluorobenzene (DNFB) and its effects on the proliferation of the lymphocytes. METHODS: ① An ACD mouse model was established by stimulation with DNFB, and then the mice were injected intraperitoneally with different dosages of OMT, PBS and hydrocortisone (HCT) respectively, the swelling degree of their auricles was examined. ② Carboxyfluorescein diacetate, succinimidyl ester (CFDA-SE) dye and flow cytometer were used to examine the fluorescence intensity changes of lymphocytes stimulated by polyclonal stimulator ConA and OMT. RESULTS: ① compared with PBS group, OMT possessed the strong inhibitory effect on the ACD caused by DNFB in a dose-dependent manner, and its inhibitory effect was equivalent to the HCT of the same dosage with fewer side effects. ② In vitro experiments proved that OMT (500, 125 and 31 mg/L) had the ability to restrain the proliferation of lymphocytes of mouse. CONCLUSION: OMT possesses an inhibitory effect on the ACD induced by DNFB, and OMT is a kind of immunosuppressor. 相似文献
992.
AIM: To establish a new human endometial carcinoma cell line for basic and clinical study. METHODS: The minced tumor tissues were inoculated subcutaneously into the back of nude mice. After forming solid tumor, the mice were killed and the transplant was taken out for primery culture. RESULTS: The established cell line was maintained by serial passages, named EAC. EAC cell line grew rapidly,steadily, and it had similar microscopic morphology to adenocarcinoma cell. Chromosome analysis reveal EAC chromosome counts ranging in hyperdiploid. The expression of ER, PR, P53, MDM2 were negative by SP immunohistochemistry. Tumorigenicity of EAC in nude mice was 100%. CONCLUSION: A new human endometrial carcinoma, EAC, is established successfully, which is helpful for the basic and clinical study of endometrial carcinoma. 相似文献
993.
AIM: To investigate the expression of TNF-α, TGF-β in patients with oral lichen planus (OLP) and normal oral mucosa (NOM). METHODS: An immunohistochemical technique was performed to detect TNF-α, TGF-β1 and TGF-β2 expression in 22 cases with OLP and 10 normal controls. RESULTS: In lamina propria of OLP, the expression of TNF-α and TGF-β1 were increased, whereas TGF-β2 did changed significantly compared with control group. TNF-α positive signal were mostly found in macrophages, lymphocytes. TGF-β1 positive cell was present in macrophages, endothelial cells and fibrocytes. CONCLUSION: TNF-α and TGF-β1 play an important role in the development and maintenance of OLP local inflammation. 相似文献
994.
虫酰肼的高效液相色谱分析 总被引:5,自引:0,他引:5
本文建立了一种虫酰肼的高效液相色谱分析方法。方法的变异系数0.39%,回收率在99.1%-102.8%之间,外标法定量。 相似文献
995.
模拟螟害对水稻产量影响的研究 总被引:3,自引:0,他引:3
设置了模拟螟害、氮肥和基本苗三因索随机区组试验。结果表明各因素对产量及其构成因素的影响都极显著。水稻9—15叶期,分别损失分蘖8%、20%、20%、4%、4%、1%、1%以上亩穗才显著减少,分别损失分蘖8%、20%、20%、12%、8%、4%、1%以上才显著减产。随着损失叶期和损失度增大,亩穗渐减,着粒数、实粒数和千粒重不同程度增加。12—14叶期,1%—2%的损失产量反而略提高。讨论了氮肥和基本苗对产量及其构成因素的影响,认为每亩(666.7m~2)施5kg 纯氮的氮肥、移栽3.428万棵苗/亩有利于高产。 相似文献
996.
饲料加工工艺与饲料质量 总被引:4,自引:0,他引:4
1粉碎工艺 1.1粒度与混合均 匀度粉碎后的物料 表面积增大,有利于 粉体混合均匀,随着 单位体积内粒子数的 增加,混合物的变异 系数减少。 有研究发现,玉 米经粉碎过1.7mm 筛后,只需混合1.5 min即可使变异系数 小于10%,而粗粉碎 (6.4mm)的玉米混合 3min变异系数大于 10%,而小于20%。 无论使用卧赋或立式 螺带混合机,混合效 果均不理想。 1.2粒度与颗粒质 量粒度是影响颗粒 质量的重要因素。一 般认为,压粒用的物料以粗中细比例适当为好。过多的粗物料,影响颗粒的成形,因为细物料可增加粉体… 相似文献
997.
Plant root hairs are important structures on the root surface for absorption of water, inorganic and organic nutrients. The root hairs which are regulated by both genetic and environmental factors, also play important roles when plants are dealing with environmental stress conditions. In this review, we analyzed how stress such as P deficiency, genetic factors and the core regulatory network composed of ABA,ETH, ABA work together during the regulation of rice root hair development. At last, we come up with issues which remains unclear but are critical and could be potential research focus. 相似文献
998.
检测儿科常见疾病患者中的红细胞免疫粘附功能发现:(1)新生儿的红细胞免疫粘附功能尚未发育完善,低于正常儿童水平;(2)急性肾炎患儿的红细胞免疫粘附功能呈现继发性增强;(3)肾病综合征、风湿性疾病、大叶性肺炎、秋季腹泻及急性白血病等患儿的红细胞免疫粘附功能呈继发性降低;(4)红细胞免疫粘附功能的变化与疾病的发展及转归有关。提示在儿科疾病的诊断和治疗中观察患儿的红细胞免疫粘附功能有重要意义。 相似文献
999.
1000.