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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
3.
Jiao-Tian Xu Yuan Qian Wei Wang Xiao-Xiang Chen Yang Li Yu Li Zhi-Yong Yang Xiao-Bin Song Di Lu Xing-Li Deng 《中国神经再生研究》2020,(1):112-119
Previous studies have shown that neural stem cell transplantation has the potential to treat Parkinson’s disease,but its specific mechanism of action is still unclear.Stromal cell-derived factor-1 and its receptor,chemokine receptor 4(CXCR4),are important regulators of cell migration.We speculated that the CXCR4/stromal cell-derived factor 1 axis may be involved in the therapeutic effect of neural stem cell transplantation in the treatment of Parkinson’s disease.A Parkinson’s disease rat model was injected with 6-hydroxydopamine via the right ascending nigrostriatal dopaminergic pathway,and then treated with 5μL of neural stem cell suspension(1.5×104/L)in the right substantia nigra.Rats were intraperitoneally injected once daily for 3 days with 1.25 mL/kg of the CXCR4 antagonist AMD3100 to observe changes after neural stem cell transplantation.Parkinson-like behavior in rats was detected using apomorphine-induced rotation.Immunofluorescence staining was used to determine the immunoreactivity of tyrosine hydroxylase,CXCR4,and stromal cell-derived factor-1 in the brain.Using quantitative real-time polymerase chain reaction,the mRNA expression of stromal cell-derived factor-1 and CXCR4 in the right substantia nigra were measured.In addition,western blot assays were performed to analyze the protein expression of stromal cell-derived factor-1 and CXCR4.Our results demonstrated that neural stem cell transplantation noticeably reduced apomorphine-induced rotation,increased the mRNA and protein expression of stromal cell-derived factor-1 and CXCR4 in the right substantia nigra,and enhanced the immunoreactivity of tyrosine hydroxylase,CXCR4,and stromal cell-derived factor-1 in the brain.Injection of AMD3100 inhibited the aforementioned effects.These findings suggest that the stromal cell-derived factor-1/CXCR4 axis may play a significant role in the therapeutic effect of neural stem cell transplantation in a rat model of Parkinson’s disease.This study was approved by the Animal Care and Use Committee of Kunming Medical University,China(approval No.SYXKK2015-0002)on April 1,2014. 相似文献
4.
Alzheimer’s disease is characterized by the extracellular accumulation of the amyloidβin the form of amyloid plaques and the intracellular deposition of the microtubule-associated protein tau in the form of neurofibrillary tangles.Most of the Alzheimer’s drugs targeting amyloidβhave been failed in clinical trials.Particularly,tau pathology connects greatly in the pathogenesis of Alzheimer’s disease.Tau protein enhances the stabilization of microtubules that leads to the appropriate function of the neuron.Changes in the quantity or the conformation of tau protein could affect its function as a microtubules stabilizer and some of the processes wherein it is involved.The molecular mechanisms leading to the accumulation of tau are principally signified by numerous posttranslational modifications that change its conformation and structural state.Therefore,aberrant phosphorylation,as well as truncation of tau protein,has come into focus as significant mechanisms that make tau protein in a pathological entity.Furthermore,the shape-shifting nature of tau advocates to comprehend the progression of Alzheimer’s disease precisely.In this review,we emphasize the recent studies about the toxic and shape-shifting nature of tau in the pathogenesis of Alzheimer’s disease. 相似文献
5.
目的:采用响应面法优化瓜蒌子中总三萜类成分的含量测定。方法:通过Box-behnken响应面法优化测定瓜蒌子中总三萜时的最佳条件,采用分光光度法对瓜蒌子药材进行含量测定。结果:所得的最佳条件为料液比40:1,超声时间20min,超声功率100W;测得10个产地间瓜蒌子中总三萜类成分的含量差异较大,其中9号产地(安徽1)的总三萜类成分含量最高,为45. 71mg/g,而7号产地(山东)的总三萜类成分含量最低,为15. 22mg/g。结论:Box-behnken响应面法优化瓜蒌子中总三萜类成分含量测定的方法合理,可以用于瓜蒌子中总三萜类成分的含量测定。不同产地间瓜蒌子中总三萜类成分的含量存在较大的差异。 相似文献
6.
Lycium barbarum(LB)is a traditional Chinese medicine that has been demonstrated to exhibit a wide variety of biological functions,such as antioxidation,neuroprotection,and immune modulation.One of the main mechanisms of Alzheimer’s disease is that microglia activated by amyloid beta(Aβ)transform from the resting state to an M1 state and release pro-inflammatory cytokines to the surrounding environment.In the present study,immortalized microglial cells were pretreated with L.barbarum extract for 1 hour and then treated with oligomeric Aβfor 23 hours.The results showed that LB extract significantly increased the survival of oligomeric Aβ-induced microglial cells,downregulated the expression of M1 pro-inflammatory markers(inducible nitric oxide synthase,tumor necrosis factorα,interleukin-6,and interleukin-1β),and upregulated the expression of M2 anti-inflammatory markers(arginase-1,chitinase-like protein 3,and interleukin-4).LB extract also inhibited the oligomeric Aβ-induced secretion of tumor necrosis factorα,interleukin-6,and interleukin-1βin microglial cells.The results of in vitro cytological experiments suggest that,in microglial cells,LB extract can inhibit oligomeric Aβ-induced M1 polarization and concomitant inflammatory reactions,and promote M2 polarization. 相似文献
7.
8.
《中国药房》2019,(15):2091-2095
目的:完善和提高苗药酢浆草药材的质量标准,为其深度开发提供科学依据。方法:以采集自贵州、安徽、河南等地的12批酢浆草药材为样品。观察其药材粉末的显微特征;按2015年版《中国药典》(四部)通则相关方法,对其进行薄层色谱(TLC)鉴别[展开剂为三氯甲烷-甲醇-甲酸(8:1:0.1,V/V/V)]和水分、总灰分、酸不溶性灰分及醇溶性浸出物的含量测定;采用高效液相色谱(HPLC)法测定其中异牡荆苷含量[色谱柱为Venusil XBP C18(L),流动相为乙腈-0.1%磷酸溶液(15:85,V/V),流速为1 mL/min,柱温为35℃,检测波长为338 nm,进样量为10μL]。结果:显微观察可见,本品粉末呈灰褐色至黄褐色,具有非腺毛甚多、纤维纹孔明显等特点;TLC鉴别结果显示,在供试品色谱上与对照药材色谱相应位置显相同颜色的斑点;12批药材的水分含量为6.66%~12.13%,总灰分含量为9.16%~13.79%,酸不溶性灰分含量为1.58%~4.63%,醇溶性浸出物含量为5.22%~15.79%;HPLC测定结果显示,异牡荆苷质量浓度在5.20~78.3μg/mL范围内与其峰面积具有良好的线性关系(r=0.999 0),重复性(n=9)、中间精密度(n=6)、稳定性(24 h,n=6)试验的RSD均<2.0%,加样回收率为97.54%~99.52%(RSD=0.74%,n=6),12批酢浆草药材中异牡荆苷的含量为0.036%~0.144%(n=3)。结论:本研究建立了苗药酢浆草定性、定量鉴别的方法,对提升酢浆草药材的质量标准有一定参考价值。 相似文献
9.
《中国药房》2019,(14):1902-1908
目的:建立同时测定小牛血去蛋白提取物注射液中14种元素含量的方法。方法:采用电感耦合等离子体质谱法。射频功率为1 350 W,载气(氩气)流量为1.1 L/min,碰撞气(氦气)流量为4.5 L/min,积分时间为1.5 s,等离子体气流量为18 L/min,采样深度为65 mm,进样蠕动泵转速为24.0 r/min,数据采样模式为跳峰模式,重复次数为3次。结果:镉、铅、砷、汞、钴、钒、镍、铊、银、钼、铜、铬、钡、铝的检测质量浓度线性范围分别为0.05~50μg/L(r=0.999 7)、0.05~50μg/L(r=0.999 7)、0.05~50μg/L(r=0.999 8)、0.05~50μg/L(r=0.999 5)、0.05~50μg/L(r=0.999 5)、0.05~50μg/L(r=0.999 8)、0.05~50μg/L(r=0.999 6)、0.05~50μg/L(r=0.999 5)、0.05~50μg/L(r=0.999 5)、0.05~50μg/L(r=0.999 8)、0.05~50μg/L(r=0.999 6)、0.05~50μg/L(r=0.999 6)、0.05~50μg/L(r=0.999 7)、0.5~70μg/L(r=0.999 8);定量限分别为0.003 1、0.008 9、0.016 0、0.025 0、0.002 1、0.006 9、0.038 1、0.002 1、0.005 5、0.002 0、0.023 1、0.005 0、0.002 0、0.324 9μg/L;检测限分别为0.000 9、0.002 7、0.004 8、0.007 5、0.000 6、0.002 1、0.011 4、0.000 6、0.016 5、0.000 6、0.006 9、0.001 5、0.000 6、0.097 5μg/L;精密度、稳定性、重复性试验的RSD均小于8%;加样回收率分别为87.4%~94.3%(RSD=2.6%,n=9)、110.3%~118.2%(RSD=1.8%,n=9)、89.8%~99.7%(RSD=3.1%,n=9)、77.7%~84.4%(RSD=2.5%,n=9)、105.6%~113.4%(RSD=2.3%,n=9)、106.7%~116.5%(RSD=2.7%,n=9)、89.1%~104.5%(RSD=4.5%,n=9)、105.6%~118.6%(RSD=3.6%,n=9)、77.8%~88.0%(RSD=4.0%,n=9)、106.7%~116.1%(RSD=2.8%,n=9)、88.5%~97.1%(RSD=3.1%,n=9)、80.5%~88.6%(RSD=2.9%,n=9)、85.2%~99.4%(RSD=4.2%,n=9)、97.6%~109.3%(RSD=3.2%,n=9)。结论:该方法操作简便、准确,精密度、稳定性、重复性均较好,可用于同时测定小牛血去蛋白提取物注射液中14种元素的含量。 相似文献