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1.
本文报告不同种的金银花中微量生物元素的分布规律:不同种的金银花中微量生物元素含量的对数与其元素的原子序数成线性关系,并呈现周期性。 相似文献
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红花水煎剂对家兔离体主动脉血管的舒张作用 总被引:11,自引:0,他引:11
目的 观察红花Carthamustinctorius (DFCT)水煎剂对血管肌条的舒张作用及机制。方法 将家兔离体主动脉肌条放置于灌流肌槽中 ,记录其等长收缩。结果 DFCT对血管肌条静息张力无明显影响 ,但 2 0mg/mLDFCT水煎剂与 10 -5mol/L乙酰胆碱相似 ,可使 10 -6mol/L去甲肾上腺素预收缩血管肌条产生明显的舒张作用。去除内皮细胞、10 -4mol/LL NNA或 10 -5mol/L甲烯蓝可减弱DFCT的舒张血管作用 ,但前列腺素合成抑制剂和 β肾上腺素能受体阻断无明显影响。另外 ,4 0mg/mLDFCT水煎剂可明显抑制去内皮血管肌条去甲肾上腺和KCl的量效收缩反应 ,使其PD2 值分别由对照组 6 0 6± 0 0 9和 1 71± 0 33变为 5 0 7± 0 0 8和 1 35± 0 2 0。结论DFCT水煎剂可通过受体操纵Ca2 + 通道和电压依赖性Ca2 + 通道抑制外Ca2 + 内流 ,使血管肌条舒张 ,其作用与内皮释放的NO有关。 相似文献
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目的:通过探讨该病历提高临床医生对该病认识.方法:通过病史询问,体格检查,辅助检查排除其他常见病.结果:过敏性肺泡炎可以并发胸腔积液.结论:早期诊断,及时给予激素治疗,预后良好. 相似文献
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滨蒿化学成分的研究(Ⅲ) 总被引:5,自引:0,他引:5
目的 :研究滨蒿花蕾的化学成分。方法 :采用硅胶、聚酰胺、SephadexLH - 2 0柱色谱和高压液相色谱法分离化学成分 ,UV ,NMR和MS等方法进行结构鉴定。结果 :从干燥花蕾中又分离鉴定了 6个化合物 ,为 β-谷甾醇 (Ⅸ ) ,6 ,7-二甲氧基香豆素 (Ⅹ ) ,6-去甲基茵陈色原酮 (Ⅺ ) ,茵陈香豆酸乙 (Ⅻ ) ,华良姜素 ( ) ,异东莨菪苷 ( )。结论 :化合物Ⅺ ,Ⅻ , ,为首次从该植物中分离得到 ,其中化合物Ⅺ为一新化合物。 相似文献
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Dolichandrone serrulata flower extract ameliorates male reproductive damages in type 2 diabetic rats
Supataechasit Yannasithinon Chadaporn Chaimontri Tarinee Sawatpanich Sitthichai Iamsaard 《Andrologia》2021,53(2):e13911
Dolichandrone serrulata flower (DSF) has been believed to reduce blood glucose in hyperglycaemic persons with sub-fertility but its effect on improvement of male reproductive impairment has never been elucidated scientifically. This study attempted to investigate the hypoglycaemic effects of DSF on male reproductive damages in type 2 diabetes mellitus (T2DM) rats. Adult Sprague Dawley rats were divided into four groups (control, T2DM, DSF200 + T2DM and DSF600 + T2DM; n = 10/each). Control rats received low-fat diet for 14 days before saline injection while streptozocin (50 mg/kg BW) induced T2DM groups received high-fat diet and were orally administered with DSF (200 and 600 mg/kg BW) for 28 days. At the end, fasted blood glucose (FBG), malondialdehyde (MDA), testosterone, sperm quality, histology and protein expressions were examined. The result showed that DSF decreased high FBG and testicular MDA and increased testosterone levels of T2DM-treated rats. Low-sperm quality and histological malfunction were ameliorated in DSF-treated group. There was significant decrease in the expression of androgen receptor, heat-shock 70 and steroidogenic acute regulatory proteins of T2DM-treated rats. Our study demonstrated changes of six bands (116, 51, 45, 39, 35 and 29 kDas) of tyrosine-phosphorylated proteins. In conclusion, DSF could reduce the FBGand ameliorate the reproductive damages in male T2DM rats. 相似文献
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Evidence that CRABS CLAW and TOUSLED have conserved their roles in carpel development since the ancestor of the extant angiosperms
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Fourquin C Vinauger-Douard M Fogliani B Dumas C Scutt CP 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(12):4649-4654
The carpel is the female reproductive organ specific to flowering plants. We aim to define the genes that controlled carpel development in the common ancestor of this group as a step toward determining the molecular events that were responsible for the evolution of the carpel. CRABS CLAW (CRC) and TOUSLED (TSL) control important aspects of carpel development in the model plant, Arabidopsis thaliana. The basal angiosperm species Amborella trichopoda and Cabomba aquatica very likely represent the two most early diverging groups of flowering plants. We have identified putative orthologues of CRC and TSL from A. trichopoda and C. aquatica, respectively. We demonstrate the expression patterns of these genes in carpels to be very highly conserved, both spatially and temporally, with those of their Arabidopsis orthologues. We argue that CRC and TSL in Arabidopsis are likely to have conserved their respective roles in carpel development since the common ancestor of the living flowering plants. We conclude that a divergent role shown for the CRC orthologue in rice, DROOPING LEAF, most probably arose specifically in the monocot lineage. We show that, in addition to its expression in carpels, the TSL orthologue of C. aquatica is expressed in tissues that contribute to buoyancy and argue that its role in these tissues may have arisen later than its role in carpel development. 相似文献