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1.
目的 建立蒙药绿松石的质量标准。方法 收集不同产地绿松石,共10批。观察绿松石样品和粉末的性状并进行理化鉴别;按2020年版《中国药典》(四部)通则方法测定绿松石样品中水分、浸出物含量;采用原子吸收光谱法测定绿松石样品铜元素含量。结果 绿松石为不规则、周围带有黑石的块状物,表面蓝绿色,体重,质硬脆,难砸碎,断面呈贝壳状,蜡样光泽,粉末呈灰绿色,无臭,味淡;理化鉴别结果显示,呈铜盐反应;10批次样品中水分含量为0.41%-3.94%(SD=1.37%),浸出物含量为0.21%-0.81%(SD=0.21%),铜元素含量为3.03%-4.63%(SD=0.63%)。结论 初步拟定绿松石中水分含量不得超多5.0%、浸出物含量不得低于0.10%,铜元素含量应为2.60%-4.84%,制定的标准可用于蒙药材绿松石的质量控制。  相似文献   
2.
多囊卵巢综合征(polycystic ovary syndrome,PCOS)是一种内分泌代谢紊乱综合征,临床表现高度异质性。肥胖是PCOS异质性临床表现之一,超过50%的PCOS患者超重或肥胖。肥胖型PCOS主要表现为高雄激素血症、中心型肥胖和糖脂代谢紊乱,非肥胖型PCOS主要表现为黄体生成激素(luteinizing hormone,LH)水平异常升高。尽管肥胖型和非肥胖型PCOS均存在内分泌代谢异常,然而肥胖可加重PCOS糖脂代谢紊乱;肥胖型PCOS还表现脂肪代谢的异常。综述肥胖型PCOS患者的临床特征、性激素水平、糖脂代谢特征,旨在为肥胖型和非肥胖型PCOS患者新的分型诊治提供参考。  相似文献   
3.
Metabolism describes the series of chemical reactions that are concerned with the provision of energy to biological systems. They may be divided into reactions involved in energy yield (catabolism: demand exceeds supply), and energy storage (anabolism: supply exceeds demand). Regulation of these pathways is critical for homeostasis, and derangements in metabolism are seen in a wide variety of pathological processes. Understanding metabolism is key to the treatment of many diseases, notably diabetes, as well as underpinning clinical nutritional support.  相似文献   
4.
Dosage form is a mean used for the delivery of drug to a living body. In order to get the desired effect the drug should be delivered to its site of action at such rate and concentration to achieve the maximum therapeutic effect and minimum adverse effect. Since oral route is still widely accepted route but having a common drawback of difficulty in swallowing of tablets and capsules. Therefore a lot of research has been done on novel drug delivery systems. This review is about oral dispersible tablets a novel approach in drug delivery systems that are now a day''s more focused in formulation world, and laid a new path that, helped the patients to build their compliance level with the therapy, also reduced the cost and ease the administration especially in case of pediatrics and geriatrics. Quick absorption, rapid onset of action and reduction in drug loss properties are the basic advantages of this dosage form.  相似文献   
5.
(+/?)3,4‐methylenedioxymethamphetamine (MDMA, “ecstasy”) is an abused psychostimulant that produces strong monoaminergic stimulation and whole‐body hyperthermia. MDMA‐induced thermogenesis involves activation of uncoupling proteins (UCPs), primarily a type specific to skeletal muscle (UCP‐3) and absent from the brain, although other UCP types are expressed in the brain (e.g. thalamus) and might contribute to thermogenesis. Since neuroimaging of brain temperature could provide insights into MDMA action, we measured spatial distributions of systemically administered MDMA‐induced temperature changes and dynamics in rat cortex and subcortex using a novel magnetic resonance method, Biosensor Imaging of Redundant Deviation in Shifts (BIRDS), with an exogenous temperature‐sensitive probe (thulium ion and macrocyclic chelate 1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetramethyl‐1,4,7,10‐tetraacetate (DOTMA4?)). The MDMA‐induced temperature rise was greater in the cortex than in the subcortex (1.6 ± 0.4 °C versus 1.3 ± 0.4 °C) and occurred more rapidly (2.0 ± 0.2 °C/h versus 1.5 ± 0.2 °C/h). MDMA‐induced temperature changes and dynamics in the cortex and body were correlated, although the body temperature exceeded the cortex temperature before and after MDMA. Temperature, neuronal activity, and blood flow (CBF) were measured simultaneously in the cortex and subcortex (i.e. thalamus) to investigate possible differences of MDMA‐induced warming across brain regions. MDMA‐induced warming correlated with increases in neuronal activity and blood flow in the cortex, suggesting that the normal neurovascular response to increased neural activity was maintained. In contrast to the cortex, a biphasic relationship was seen in the subcortex (i.e. thalamus), with a decline in CBF as temperature and neural activity rose, transitioning to a rise in CBF for temperature above 37 °C, suggesting that MDMA affected CBF and neurovascular coupling differently in subcortical regions. Considering that MDMA effects on CBF and heat dissipation (as well as potential heat generation) may vary regionally, neuroprotection may require different cooling strategies. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
6.
Evidence continues to grow on potential environmental health hazards associated with engineered nanomaterials (ENMs). While the geno- and cytotoxic effects of ENMs have been investigated, their potential to target the epigenome remains largely unknown. The aim of this study is two-fold: 1) determining whether or not industry relevant ENMs can affect the epigenome in vivo and 2) validating a recently developed in vitro epigenetic screening platform for inhaled ENMs. Laser printer-emitted engineered nanoparticles (PEPs) released from nano-enabled toners during consumer use and copper oxide (CuO) were chosen since these particles induced significant epigenetic changes in a recent in vitro companion study. In this study, the epigenetic alterations in lung tissue, alveolar macrophages and peripheral blood from intratracheally instilled mice were evaluated. The methylation of global DNA and transposable elements (TEs), the expression of the DNA methylation machinery and TEs, in addition to general toxicological effects in the lung were assessed. CuO exhibited higher cell-damaging potential to the lung, while PEPs showed a greater ability to target the epigenome. Alterations in the methylation status of global DNA and TEs, and expression of TEs and DNA machinery in mouse lung were observed after exposure to CuO and PEPs. Additionally, epigenetic changes were detected in the peripheral blood after PEPs exposure. Altogether, CuO and PEPs can induce epigenetic alterations in a mouse experimental model, which in turn confirms that the recently developed in vitro epigenetic platform using macrophage and epithelial cell lines can be successfully utilized in the epigenetic screening of ENMs.  相似文献   
7.
目的建立环境水样中痕量铜的浊点萃取(cloud point extraction,CPE)-火焰原子吸收光谱(flame atomic absorption spectrometry,FAAS)测定法。方法样品在p H 9.5的条件下,加入0.4 ml的1 mmol/L 2-(5-溴-2-吡啶偶氮)-5-二乙氨基酚(5-Br-PADAP)溶液,0.1%氯化钙溶液0.1 ml,5%(W/V)Triton X-114溶液0.8 ml,40℃加热15 min后离心,采用火焰原子吸收光谱法进行检测。结果在2~240μg/L的线性范围内,所得回归方程为A=0.002 7c+0.024 6,r=0.995 8。以3倍信噪比计算,方法的检出限为0.62μg/L,富集倍数为36.58倍,平均加标回收率为96.28%~98.08%,RSD为1.67%~3.13%。结论该方法简单、灵敏,具有良好的重现性,适用于环境水样中痕量铜的测定。  相似文献   
8.
目的 通过UHPLC-Q-TOF-MS代谢组学探讨艾灸关元穴对老年大鼠肾代谢物的影响,进而为艾灸关元穴的作用机制提供参考。方法 将8月龄SD雄性大鼠设为成年对照组(8只),21月龄SD雄性大鼠随机分为老年对照组(8只)、老年金匮肾气丸组(7只)、老年艾灸组(8只)。老年金匮肾气丸组每日按体重给药,老年艾灸组每日艾灸关元穴15 min,均每周5天。实验持续13周后检测大鼠肾组织线粒体呼吸耗氧速率、琥珀酸脱氢酶(SDH)活性以及血清肾功能指标,观察肾脏病理变化,结合UHPLC-Q-TOF-MS技术对大鼠的肾组织进行代谢轮廓分析,筛选代谢差异物并进行鉴定。结果 与老年对照组比较,老年艾灸组大鼠肾线粒体的呼吸耗氧速率和SDH酶的活力显著提高(P<0.01)。代谢组学结果显示,肾组织中筛选出13个共同差异化合物,分别是丁酸十二烷基酯、亚油酰胺、5-甲基四氢叶酸、PC(16∶0/22∶5(7Z,10Z,13Z,16Z,19Z))、6,8-二羟基嘌呤、1,2,3-丙烷三羧酸、3-(4-甲氧基苯基)-2-氧代丙酸、吲哚-3-乙酰甘氨酸、亚麻油酸、9,10-环氧十八烷酸、二十二碳五烯酸(22n-6)、牛磺胆酸、LysoPS (18∶0/0∶0)。结论 艾灸关元穴可通过调控老年大鼠的牛磺酸和亚牛磺酸代谢、α-亚麻酸代谢、亚油酸代谢、甘油磷脂代谢来调节肾的能量代谢。  相似文献   
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