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51.
千层塔中三萜成分的研究 总被引:5,自引:0,他引:5
前曾报道自千层塔[Huperzia serrata Thunb.(Trev)=Lycopodium serratum Thunb(Trev.)]中分得具有胆碱酯酶抑制活性的新生物碱——石杉碱甲、石杉碱乙、甲基石杉碱乙及已知生物碱8-deoxyserratinine,serratinine,lycodoline及lycoclavine。为进一步阐明该植物的化学成分,我们对其三萜成分进行了研究。从浙江安吉产的千层塔植物中分到六个石松三萜,其中一个为新化合物,经下述方法推定为serratenediol-21-acetate(Ⅰ)。另五 相似文献
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本文报道我国西南产麻黄——丽江麻黄Ephedra likiangensis Florin、匍枝丽江麻黄E.likiangensis f.mairei(Florin)C.Y.Cheng、藏麻黄E.saxatilis Royle ex Florin、山岭麻黄E.gerardiana Wall、垫状山岭麻黄E.gerardiana Var.congesta C.Y.Cheng、矮麻黄E.minuta Florin和异株矮麻黄E.minuta var.dioeca C.Y.Cheng,以及形态组织特征较特殊的宁夏产斑子麻黄E.lepidosperma C.Y.Cheng、新疆产窄膜麻黄E.lomatolepis Schrenk,西藏产西藏中麻黄E.intermedia var.tibetica Stapf的生药形态组织学研究结果。并根据对国产麻黄的生药形态组织学的系统研究结果,分别编写了各种国产麻黄(包括13种3变种1变型)的生药性状和生药显微特征检索表。 相似文献
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微球给药系统的工艺优化研究 总被引:8,自引:2,他引:8
目的 :阐述微球制备工艺中的优化技术。方法 :检索近年来国内外文献并进行整理和归纳。结果 :单因素设计、正交设计、均匀设计、因子设计是目前微球工艺中常用的优化方法。结论 :通过上述方法优化微球的制备工艺 ,可在一定条件下达到经济、高效的目的 ,更理想的优化技术尚有待研究 相似文献
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Yi Zhu Na Li Mingyang Huang Xi Chen Yu A. An Jianping Li Shangang Zhao Jan-Bernd Funcke Jianhong Cao Zhenyan He Qingzhang Zhu Zhuzhen Zhang Zhao V. Wang Lin Xu Kevin W. Williams Chien Li Kevin Grove Philipp E. Scherer 《药学学报(英文版)》2022,12(7):3063-3072
Adipose tissue is a promising target for treating obesity and metabolic diseases. However, pharmacological agents usually fail to effectively engage adipocytes due to their extraordinarily large size and insufficient vascularization, especially in obese subjects. We have previously shown that during cold exposure, connexin43 (Cx43) gap junctions are induced and activated to connect neighboring adipocytes to share limited sympathetic neuronal input amongst multiple cells. We reason the same mechanism may be leveraged to improve the efficacy of various pharmacological agents that target adipose tissue. Using an adipose tissue-specific Cx43 overexpression mouse model, we demonstrate effectiveness in connecting adipocytes to augment metabolic efficacy of the β3-adrenergic receptor agonist Mirabegron and FGF21. Additionally, combing those molecules with the Cx43 gap junction channel activator danegaptide shows a similar enhanced efficacy. In light of these findings, we propose a model in which connecting adipocytes via Cx43 gap junction channels primes adipose tissue to pharmacological agents designed to engage it. Thus, Cx43 gap junction activators hold great potential for combination with additional agents targeting adipose tissue. 相似文献
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Sebastian N. Kunz Jiri Adamec Bettina Zinka Daniela Münzel Peter B. Noël Simon Eichner Axel Manthei Nico Grove M. Graw Oliver Peschel 《International journal of legal medicine》2013,127(1):119-126
The Taser® eXtended Range Electronic Projectile (XREP®) is a wireless conducted electrical weapon (CEW) designed to incapacitate a person from a larger distance. The aim of this study was to analyze the ballistic injury potential of the XREP. Twenty rounds were fired from the Taser®X12 TM shotgun into ballistic soap covered with artificial skin and clothing at different shooting distances (1–25 m). One shot was fired at pig skin at a shooting distance of 10 m. The average projectile velocity was 67.0 m/s. The kinetic energy levels on impact varied from 28–52 J. Depending on the intermediate target, the projectiles penetrated up to 4.2 cm into the ballistic soap. On impact the nose assembly did not separate from the chassis, and no electrical activation was registered. Upon impact, a skin penetration of the XREP cannot be excluded. However, it is very unlikely at shooting distances of 10 m or more. Clothing and a high elasticity limit of the target body area can significantly reduce the penetration risk on impact. 相似文献
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Insights in particulate matter‐induced allergic airway inflammation: Focus on the epithelium
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K. C. De Grove S. Provoost G. G. Brusselle G. F. Joos T. Maes 《Clinical and experimental allergy》2018,48(7):773-786
Outdoor air pollution is a major environmental health problem throughout the world. In particular, exposure to particulate matter (PM) has been associated with the development and exacerbation of several respiratory diseases, including asthma. Although the adverse health effects of PM have been demonstrated for many years, the underlying mechanisms have not been fully identified. In this review, we focus on the role of the lung epithelium and specifically highlight multiple cytokines in PM‐induced respiratory responses. We describe the available literature on the topic including in vitro studies, findings in humans (ie observations in human cohorts, human controlled exposure and ex vivo studies) and in vivo animal studies. In brief, it has been shown that exposure to PM modulates the airway epithelium and promotes the production of several cytokines, including IL‐1, IL‐6, IL‐8, IL‐25, IL‐33, TNF‐α, TSLP and GM‐CSF. Further, we propose that PM‐induced type 2‐promoting cytokines are important mediators in the acute and aggravating effects of PM on airway inflammation. Targeting these cytokines could therefore be a new approach in the treatment of asthma. 相似文献
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