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61.
目的测定中药常通口服液中重金属砷(As)的含量。 方法采用原子荧光光度法,负高压300 V,光源用砷空心阴极灯,灯电流为60 mA,原子化器高度8.0 mm,载气流量300 mL·min-1,屏蔽气流量700 mL·min 1。结果重金属砷在0.4~25.6 ng·mL-1浓度范围内线性关系良好,r=0.999 7,平均回收率为98.27%,RSD=2.83%(n=5)。结论该法简单、快速、灵敏,常通口服液中重金属砷含量符合规定。  相似文献   
62.
γ-巯丙基键合硅胶脱除龙胆提取液中的镉   总被引:1,自引:0,他引:1  
目的:研究γ-巯丙基键合硅胶(MPS)脱除龙胆提取液中镉(Cd)的最佳工艺,并对其脱镉性能进行评价.方法:采用静态吸附和动态吸附的方式考察镉的脱除率,并以镉脱除率、含固量、HPLC指纹图谱等指标综合评价MPS的脱镉性能.结果:静态吸附的工艺参数:药液浓度相当于0.20 g(药材)·mL-1,吸附时间为120 min,药材量-MPS 15:1;动态吸附的工艺参数:径高比为1:3.5,药液浓度相当于0.20 g(药材)·mL-1,药液流速0.9 mL· min-1,药材量-MPS 50:1;龙胆药液脱镉前后的含固量及HPLC指纹图谱无显著性差异.结论:γ-巯丙基键合硅胶(MPS)能有效地脱除龙胆药液中的镉,脱镉性能良好.  相似文献   
63.
目的:研究沉积型禹余粮对出血模型大鼠血液中相关止血指标及血清中金属离子的影响。方法:采用华法林钠建立出血大鼠模型,实验动物分为空白组、模型组、粉末组、水煎液组。采用酶联免疫法(ELISA)等测定给药15 d各组大鼠全血中6-酮-前列腺素F(6-keto-PGF),血栓素B2(TXB2),花生四烯酸(AA),内皮素-1(ET-1),血小板活化因子(PAF),P-选择素(PS),Ca2+的含量。利用电感耦合等离子体发射光谱(ICP-OES),电感耦合等离子体质谱法(ICP-MS)测定各组大鼠给药0,5,10,15 d血清样品中Na,Mg,K,Ca,Fe,Al,Li,Be,Ti,V,Cr,Mn,Co,Ni,Cu,Zn,As,Sr,Cd,Sn,Sb,Ba,Pb 23种金属元素或无机元素的含量。结果:与模型组相比,粉末组、水煎液组均能显著降低血液中6-keto-PGF的含量(P<0.05),均能显著升高TXB2,AA,ET-1,PAF,PS,Ca2+的含量(P<0.01),具积极有益的调节作用。粉末组对大鼠血清Na,K,Ca,Fe,Li,Ti,V,Co,Cu,Zn 10种金属元素具有显著积极的调节作用(P<0.05,P<0.01);水煎液组对大鼠血清中Na,K,Ca,Fe,Li,V,Ni,Cu,Zn,Sr 10种金属元素有显著积极调节(P<0.05,P<0.01)。粉末组能显著降低Cr的含量(P<0.01),水煎液组能显著降低Cr(P<0.01),Pb(P<0.05)的含量。结论:沉积型禹余粮粉末、水煎液均对华法林出血模型大鼠具有明确、积极的干预作用,可通过增强血管收缩能力、促进刺激血小板活化,从而增加血小板聚集率和血液黏稠度等作用起到凝血作用。Na,K,Ca,Fe,Li,Ti,V,Co,Cu,Zn,Ni,Sr等金属元素群可能是其发挥止血效应的物质基础。根据以上检测指标,综合来看,粉末组与水煎液组干预效果基本相当。  相似文献   
64.
抗肿瘤金属配合物药物及其药理作用的研究进展   总被引:1,自引:3,他引:1  
自从顺铂作为抗肿瘤药物被开发利用以来,无机金属配合物药物已成为新的一类抗癌化疗药物。该文参阅国内外相关文献,介绍抗肿瘤铂及其它金属配合物药物的抗肿瘤机制及其药理作用,对抗肿瘤金属配合物药物的研究进展进行综述。  相似文献   
65.
Four gold(I) complexes conceived as anticancer agents were synthesized by reacting [Au(PEt3)Cl] and [Au(PPh3)Cl] with ligands derived from δ‐d ‐gluconolactone. The ligands’ structure was designed to combine desired biological properties previously reported for each group. Ligands were synthesized from δ‐d ‐gluconolactone via ketal protection and hydrazide formation followed by cyclization with CS2 to produce the novel oxadiazolidine‐2‐thione 7 and 8 . Increasing of the ligands’ lipophilicity via ketal protection proved useful since all four gold(I) complexes showed anticancer and antileishmanial properties. The IC50 values are at low micromolar range, varying from 2 to 3 μm for the most active compounds. The free D‐gluconate 1,3,4 oxadiazole‐derived ligands were neither toxic nor presented anticancer or antileishmanial properties. Triethylphosphine‐derived compounds 9 and 10 were more selective against B16‐F10 melanoma cell line. Although similar in vitro antileishmanial activity was observed for the gold(I) precursors themselves and their derived complexes, the latter were three times less toxic for human THP‐1 macrophage cell line; this result is attributed to an isomeric variation of the D‐gluconate ligand and the oxadiazole portion, which was one of the key concepts behind this work. These findings should encourage further research on gold(I) complexes to develop novel compounds with potential application in cancer and leishmaniasis chemotherapy.  相似文献   
66.
目的检测川崎病患儿血清中基质金属蛋白酶-3(MMP-3)、基质金属蛋白酶-9(MMP-9)及其特异性组织抑制剂-1(TIMP-1)水平的变化,以探讨上述因子水平的变化与冠状动脉病变的关系。方法收集2011年1月~2012年9月在本院儿科住院的川崎病患儿,设为观察组,采取ELISA法测定川崎病患儿急性期和恢复期血清MMP-3、MMP-9和TIMP-1的含量,并与同期进行健康体检的正常健康儿童(设为对照组)进行对比观察,通过心脏彩超检查明确川崎病患儿冠状动脉损伤情况。结果观察组与对照组MMP-3、MMP-9、TIMP-1检测值及MMP-3/TIMP-1、MMP-9/TIMP-1比较,差异均有统计学意义(P〈0.05、P〈0.01);观察组中有冠状动脉病变组各检测因子结果与无冠状动脉病变组比较差异有统计学意义(P〈0.01)。结论 MMP-3、MMP-9与TIMP-1均参与了川崎病的病理生理过程,对早期诊断冠状动脉病变有提示作用,且MMP-3/TIMP-1、MMP-9/TIMP-1比值持续失调可判断冠状动脉炎症病变的严重程度。  相似文献   
67.
目的探讨孕期重金属元素和微量元素水平与子代先天性心脏病(简称先心病)的相关性,并建立孕期重金属元素和微量元素水平与子代先心病发生概率的预测模型。方法基于2010~2012年在甘肃省妇幼保健院开展的前瞻性出生队列研究,采用巢式病例对照研究方法,对14359名孕妇进行随访观察,以随访观察期内其子代确诊先心病的97名孕妇为先心病组,从队列人群中以1∶2的比例匹配194名子代未患先心病的孕妇为对照组。采用电感耦合等离子体质谱测定孕母孕20~24周时血液样本和胎儿脐血样本中的重金属元素和微量元素水平。采用多因素logistic回归分析评估重金属元素和微量元素水平与子代先心病之间的关联,并构建孕期重金属元素和微量元素水平与子代先心病发生概率的列线图预测模型。结果与对照组相比,先心病组孕妇血液样本中铝(aluminium,Al)、钠(natrium,Na)、钙(calcium,Ca)、钛(titanium,Ti)、硒(selenium,Se)、锶(strontium,Sr)、锡(stannum,Sn)、锑(stibium,Sb)、钡(barium,Ba)、钍(thorium,Th)水平较高,差异有统计学意义(P<0.05);先心病组脐血样本中Al、锌(zinc,Zn)、镁(magnesium,Mg)、钾(kalium,K)、Ca、Ti、铬(chromium,Cr)、铜(copper,Cu)、砷(arsenic,As)、Se、Sr、银(argentum,Ag)、镉(cadmium,Cd)、Sn、铅(plumbum,Pb)水平显著高于对照组(P<0.05)。多因素logistic回归分析显示,孕妇血液样本中Sb水平升高,其子代患先心病的风险显著增加(^(a)OR=4.81,P=0.004);而在脐血样本中,高浓度水平的Al(^(a)OR=4.22,P=0.013)、Mg(^(a)OR=8.00,P=0.014)、Pb(^(a)OR=3.82,P=0.049)与先心病的发生风险增加存在关联。孕期重金属元素和微量元素水平与子代先心病的预测模型中纳入的变量有:孕妇血Al、Th、Sb水平和脐血Al、Mg、Pb水平,绘制的列线图预测模型的校正曲线趋近于理想曲线。结论孕期Al、Th、Sb、Mg、Pb水平升高提示子代罹患先心病的风险增加,联合以上指标构建的列线图预测模型可以预测子代先心病的发生概率。  相似文献   
68.
This study defines the optimal parameters that allow the use of waste mollusk shells (WS) to remove heavy metals from three mining and metallurgical leachates. First, the influence of parameters such as pH, contact time, initial metal concentration, adsorbent dose and the presence of co-ions in Cu2+, Cd2+, Zn2+ and Ni2+ adsorption was investigated in synthetic solutions. Metal uptake was found to be dependent on the initial pH of the solution, the removal rate increasing with the increase in pH, showing the highest affinity at pH 5–6. The removal efficiency at lower concentrations was greater than at higher values. The competitive adsorption results on bimetallic solutions showed that the adsorption capacity of the sorbent was restricted by the presence of other ions and suppressed the uptake of heavy metals compared to the single adsorption. Cu2+ was the metal that most inhibited the removal of Cd2+, Zn2+ and Ni2+. The Langmuir isotherm provided the best fit to the experimental data for Cu2+, Cd2+ and Zn2+ and the Freundlich isotherm, for Ni2+. The data showed that the maximum adsorption capacity amax for Zn2+, Cd2+ and Cu2+, was 526.32 mg g−1, 555.56 mg g−1 and 769.23 mg g−1, respectively. Sorption kinetics data best fit the pseudo-second-order kinetic model. The results obtained in the tests with three mining and metallurgical leachates showed that WS were effective in simultaneously removing several heavy metals ions such as Cu, Ni, Zn, Cd, Ni, As and Se.  相似文献   
69.
Biomaterials with adequate properties to direct a biological response are essential for orthopedic and dental implants. The surface properties are responsible for the biological response; thus, coatings with biologically relevant properties such as osteoinduction are exciting options to tailor the surface of different bulk materials. Metal oxide coatings such as TiO2, ZrO2, Nb2O5 and Ta2O5 have been suggested as promising for orthopedic and dental implants. However, a comparative study among them is still missing to select the most promising for bone-growth-related applications. In this work, using magnetron sputtering, TiO2, ZrO2, Ta2O5, and Nb2O5 thin films were deposited on Si (100) substrates. The coatings were characterized by Optical Profilometry, Scanning Electron Microscopy, Energy-Dispersive X-ray Spectroscopy, X-ray Photoelectron Spectroscopy, X-ray Diffraction, Water Contact Angle measurements, and Surface Free Energy calculations. The cell adhesion, viability, proliferation, and differentiation toward the osteoblastic phenotype of mesenchymal stem cells plated on the coatings were measured to define the biological response. Results confirmed that all coatings were biocompatible. However, a more significant number of cells and proliferative cells were observed on Nb2O5 and Ta2O5 compared to TiO2 and ZrO2. Nevertheless, Nb2O5 and Ta2O5 seemed to induce cell differentiation toward the osteoblastic phenotype in a longer cell culture time than TiO2 and ZrO2.  相似文献   
70.
Metal foams possess remarkable properties, such as lightweight, high compressive strength, lower specific weight, high stiffness, and high energy absorption. These properties make them highly desirable for many engineering applications, including lightweight materials, energy-absorption devices for aerospace and automotive industries, etc. For such potential applications, it is essential to understand the mechanical behaviour of these foams. Producing metal foams is a highly challenging task due to the coexistence of solid, liquid, and gaseous phases at different temperatures. Although numerous techniques are available for producing metal foams, fabricating foamed metal still suffers from imperfections and inconsistencies. Thus, a good understanding of various processing techniques and properties of the resulting foams is essential to improve the foam quality. This review discussed the types of metal foams available in the market and their properties, providing an overview of the production techniques involved and the contribution of metal foams to various applications. This review also discussed the challenges in foam fabrications and proposed several solutions to address these problems.  相似文献   
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