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991.
目的:探讨针刺胃经穴后提取的血清对大鼠胃黏膜细胞表皮生长因子受体(EGFR)后信使物质表达的影响.方法:60只大鼠随机分为模型血清组、胃经血清组、胆经血清组、胃经血清 PD153035组和胆经血清 PD153035组,采用水浸束缚法制作胃黏膜损伤大鼠模型,利用链霉蛋白酶消化法分离胃黏膜细胞,分别用EGFR抑制剂PD153035和血清孵育胃黏膜细胞,应用酶联免疫吸附法检测PLCγ-1活性,同位素掺入法检测PKC活性,逆转录聚合酶链反应法检测c-mye的表达水平.结果:模型血清组大鼠胃黏膜细胞PLCγ-1,PKC和c-myc微弱表达;胃经血清组和胆经血清组大鼠胃黏膜细胞PLCγ-1,PKC和c-myc呈现较强表达,其中胃经血清组表达最高,两组相比较有显著性差异(P<0.01):胃经血清 PD153035组和胆经血清 PD153035组大鼠胃黏膜细胞PLCγ-1,PKC和c-myc的表达较弱,胃经血清组与胃经血清 PD153035组比较有显著性差异(P<0.01).结论:针刺胃经穴后提取的血清能诱导大鼠胃黏膜细胞EGFR后信使物质的活化,并且存在经脉-脏腑的特异性联系. 相似文献
992.
993.
A mutant of spikelet differentiation in rice called frizzle panicle (fzp) was discovered in the progeny of a cross between Oryza sativa ssp. indica cv. V20B and cv. Hua1B. The mutant exhibits normal plant morphology but has apparently fewer tillers. The most striking change in fzp is that its spikelet differentiation is completely blocked, with unlimited subsequent rachis branches generated from the positions where spikelets normally develop in wild-type plants. Genetic analysis suggests that fzp is controlled by a single recessive gene, which is temporarily named fzp (t). Based on its mutant phenotype, fzp (t) represents a key gene controlling spikelet differentiation. Some F2 mutant plants derived from various genetic background appeared as the "middle type", suggesting that the action of fzp (t) is influenced by the presence of redundant, modifier or interactive genes. By using simple sequence repeat (SSR) markers and bulked segregant analysis (BSA) method, fzp (t) gene was mapped in the terminal region of the long arm of chromosome 7, with RM172 and RM248 on one side, 3.2 cM and 6.4 cM from fzp (t), and RM18 and RM234 on the other side, 23.1 cM and 26.3 cM from fzp(t), respectively. These results will facilitate the positional cloning and function studies of the gene. 相似文献
994.
XIA Jiahui ZHENG Duo TANG Dongsheng DAI Heping PAN Qian LONG Zhigao LIAO Xiaodong 《中国科学C辑(英文版)》2001,44(1)
By homologous EST searching and nested PCR a new human gene GJB5encoding gap junction protein b-5 was identified. GJB5 was genetically mapped to human chromosome 1p33-p35 by FISH. RT-PCR revealed that it was expressed in skin, placenta and fetal skin. DNA sequencing of GJB5 was carried out in 142 patients with sensorineural hearing impairment and probands of 36 families with genetic diseases, including erythrokeratodermia (5 families), Charcot-Marie-Tooth disease (13), ptosis (4), and retinitis pigmentosa and deafness (14). Two missense mutations (686A→G, H229R; 25C→T, L9F) were detected in two sensorineural hearing impairment families. A heterologous deletion of 18 bp within intron was found in 3 families with heredity hearing impairment, and in one of the 3 families, a missense mutation (R265P) was identified also. But the deletion and missense mutation seemed not segregating with hearing impairment in the family. No abnormal mRNA or mRNA expression was detected in deletion carriers by RT-PCR analysis in skin tissue. Mutation analysis in 199 unaffected individuals revealed that two of them were carriers with the same 18 bp deletion. 相似文献
995.
甘露寡糖具有润肠通便、降血脂、抗结肠炎症、增强免疫及调节肠道菌群等生理功能,在食品药品等领域具有广阔的应用前景。水解法制得的甘露寡糖含有单糖、未分解聚糖、不同聚合度寡糖及盐离子等杂质,还需要进一步分离纯化。综述了近年来国内外甘露寡糖的主要纯化方法包括柱层析法、膜分离法、乙醇沉淀法和微生物发酵法等。总结了各种方法的原理、应用范围和应用实例,并对不同方法的优缺点进行了分析。 相似文献
996.
997.
目的:观察不同能量输出的Er,C r:YSGG激光照射对牙周病牙根面的影响,探讨Er,C r:YSGG激光用于牙周治疗的可行性和有效性。方法:选择因牙周病松动Ⅲo而拔除牙12颗,随机分3组,每组4颗。分别以1.5 W、2.0 W、2.5 W激光照射。扫描电镜(SEM)观察各组牙根表面和纵剖面。结果:低倍镜下各组根面改变无明显差异,表面干净,粗糙程度均匀,未见明显弹坑状痕迹;高倍镜下1.5 W激光照射组显示根面粗糙程度更均匀一致,无弹坑状改变,无熔融、炭化迹象,未见牙本质小管暴露。结论:Er,C r:YSGG激光能有效去除牙周病牙根面玷污层及病变牙骨质,根面无熔融、炭化等改变。1.5 W激光照射组优于2.0 W组和2.5 W组。 相似文献
998.
Five limonoids were isolated from the root bark of Dictamnus angustifolius G. Don. Their structures were determined as fraxinellone, obacunone, limonin, limonin diosphenol, and dictamdiol respectively, on the basis of their spectral data and chemical methods. Dictamdiol is a new natural degraded limonoid lactone derivative. Relative stereochemistry was established by two-dimensional correlation spectroscopic (COSY) experiment and biogenesis. 相似文献
999.
1000.
中国HIV-1 B亚型P55和嵌合的P55-V3病毒样颗粒候选疫苗免疫效果的研究 总被引:7,自引:0,他引:7
研究我国艾滋病病毒Ⅰ型(HIV-1)病毒样颗粒(VLP)候选疫苗的免疫原性,为疫苗进行灵长类实验提供实验依据。将gag和gag-V3 VLP不同剂量(50μg、10μg、1μg)在有佐剂(氢氧化铝)和无佐剂条件下皮下免疫小鼠,然后眼眶采血,用ELISA法观察免疫鼠血清中抗体与剂量关系,以及中和抗体滴度和抗体IgG亚型IgG1和IgG2a的水平。同时取鼠脾淋巴细胞,体外抗原刺激后收取淋巴细胞分泌上清 相似文献