环扁桃酸酯中酮酯的检查(分光光度法)

环扁桃酸酯(Cyclandelate)的化学名为3,3,5-三甲基环己醇扁桃酸酯。它是一种选择性的脑血管扩张剂。临床主要用于动脉硬化症、脑卒中及其后遗症、脑外伤后遗症等。环扁桃酸酯在生产过程中易被空气氧化成3,3,5-三甲基环己醇苯基乙醛酸酯(简称酮酯Ketoester),因此需要对产品进行酮酯的检查。我们采用环扁桃酸酯吸收度比的方法检查酮酯的量。试验如下。一、酮酯和环扁桃酸酯的薄层分离     

体外循环围术期微量元素浓度变化的动态观察

目的：观察体外循环围手术期病人血清铜，锌，铁，镁，硒浓度的动态变化。方法：对36例先天性心脏病患者围手术期不同时相血清铜，锌，铁，镁，硒浓度进行测定，结果：血清铜在转流结束时最低，术后第二天恢复；血清锌在术后第一天降至最低，于术后第五天恢复，血清铁在术后早期升高，继而下降且较长时间不能恢复，血清镁在转流结束后降低，术后第三天恢复，血清硒术后降低明显，恢复较慢，结论：术前预防性地补充某些微量元素，可能有益于病人更好地耐受缺血再灌注损伤。     

三维三步MTT法肿瘤药敏试验与芬丹明B法的比较

目的 :比较自创的三维三步MTT法 (3D3S MTT法 )与MTT法及芬丹明B法 (SRB法 )在肿瘤药敏试验中的价值。方法 :选用Hep G2、T 2 4和SKOV3三种细胞系和丝列霉素及阿霉素两种抗癌药 ,观察暴露于两种药物 3d后再培养不同时间 ,用上述三种方法测定的药敏结果。MTT法与SRB法计算肿瘤生长抑制率 (%TGI)的公式均是 :%TGI =[1 At Ac]× 1 0 0 % ;根据自建的表达MTT代谢的数学模型 ,3D3S MTT法计算 %TGI的公式是 :%TGI =1 { [lnAmax ln(Amax At) ] [lnAmax ln(Amax Ac) ] } 1 b × 1 0 0 %。结果 :三种方法测定的药物剂量 反应曲线均呈S型。MTT法测定的 %TGI要比SRB法和 3D3S MTT法测定的结果低 ,而MTT法测定的IC50 平均为SRB法和 3D3S MTT法测定结果的 3～ 5倍。而 3D3S MTT法测定的 %TGI及IC50 与SRB法测定的结果相近似。结论 :3D3S MTT法克服了MTT法测定肿瘤药敏所存在的 3～ 5倍的低估问题 ,与SRB法相比结果可靠 ,是切实可行的细胞定量分析方法     

Changes in cerebral haemodynamics,regional oxygen saturation and amplitude-integrated continuous EEG during hypoxia-ischaemia and reperfusion in newborn piglets

Perinatal asphyxia models are necessary to obtain knowledge of the pathophysiology of hypoxia-ischaemia (HI) and to test potential neuroprotective strategies. The present study was performed in newborn piglets to obtain information about simultaneous changes in cerebral oxygenation and haemodynamics and electrocortical brain activity during a 60-min period of HI and up to 2 h of reperfusion using near infrared spectrophotometry (NIRS) and the amplitude-integrated EEG (aEEG). HI was induced by occluding both carotid arteries and decreasing the fraction of inspired oxygen (FiO(2)) to 0.08-0.12 for 60 min. The mean arterial blood pressure (MABP) and heart rate increased, the oxygenated haemoglobin (O(2)Hb) decreased, and the deoxygenated haemoglobin (HHb) increased, but total haemoglobin (tHb) remained stable during the 60-min HI period. The regional oxygen saturation (rSO(2)) was significantly decreased during the whole HI period, as was the electrocortical brain activity. Upon reperfusion and reoxygenation, the MABP normalised to baseline values but the heart rate remained increased. O(2)Hb and HHb recovered to baseline values and tHb remained unchanged. As indicated by the unchanged tHb values during the HI period, it was suggested that compensatory cerebral perfusion occurred during this period, probably via the vertebrobasilar arterial system. Furthermore, in this model a clear hyperperfusion period directly upon reperfusion and reoxygenation is not present. rSO(2) showed a quick recovery to baseline values, but the aEEG-measured electrocortical brain activity remained reduced following HI. In conclusion, the rSO(2) and aEEG showed a different time profile following perinatal asphyxia. The stable tHb during HI and reperfusion in this model differs from observations in human neonates.     

Spectrophotometric method for the determination of nifedipine with 4-(methylamino)phenol and potassium dichromate

A new simple, sensitive and reproducible spectrophotometric method for the determination of nifedipine in pure and dosage forms has been proposed. It is based on the reduction of nifedipine with Zn/NNH4Cl, followed by coupling with N-methyl-1,4-benzoquinoneimine--the oxidation product of 4-(methylamino)phenol, to give a chromophore which absorbed maximally at 525 nm. The experimental conditions were optimised and Beer's law was obeyed over the concentration range of 5-175 microg ml(-1). The molar absorptivity, detection limit, recovery and RSD were found to be 1.9 x 10(3) l mol(-1) cm(-1), 1.1 microg ml(-1), 99.7-100.5% and 0.3-0.8%, respectively. The proposed method was compared favourably with the official B.P. method.     

复方益康宁片含量的测定方法

目的建立复方益康宁片中盐酸普鲁卡因和维生素B6的普通光谱系数倍率法和比值光谱测定法,以便对测定结果的准确度进行相互校验。方法根据盐酸普鲁卡因和维生素B6的普通光谱和比值光谱特征,选择适宜的测定波长对,有效地消除共存组分的干扰,实现对被测组分的准确测定。结果在选定的试验条件下,盐酸普鲁卡因和维生素B6在5.0~50.0 mg.L-1内质量浓度与吸光度线性关系良好,盐酸普鲁卡因和维生素B6的系数倍率法和比值光谱测定法的平均回收率和相对标准偏差分别为99.01%、0.41%,100.0%、0.78%,99.52%、1.16%,98.26%、0.78%。结论两法测定结果基本一致。     

一阶导数分光光度法测定硫樟脑洗剂中樟脑含量

目的建立硫樟脑洗剂中樟脑的含量测定方法。方法采用一阶导数分光光度法，测定波长为305nm，△λ为1nm。结果样品浓度线性范围是1～20mg／mL，r=0．9991，平均回收率为100．28％，RSD为1．08％。结论方法简便、准确，可用于测定硫樟脑洗剂中樟脑的含量。     

尼扎替丁注射液含量测定的方法比较

目的比较尼扎替丁注射液含量测定的两种不同方法。方法分别采用高效液相色谱法及紫外分光光度法测定尼扎替丁注射液的含量。结果两种方法测定尼扎替丁的平均回收率分别为100．67％、99．88％，RSD分别为0．41％和0．28％。结论两种方法均可作为尼扎替丁的含量测定方法，但紫外分光光度法更简便。     

紫外分光光度法测定微量亚硝酸根

目的: 研究硫堇与亚硝酸根的反应,建立一个简单、灵敏、选择性高的微量NO-2的测定方法.方法: 用紫外分光光度法测定微量NO-2.结果: 在盐酸介质中,硫堇在近紫外区有一强吸收峰位于284 nm,与NO-2反应后284 nm处吸收峰下降,吸光度的变化与溶液中NO-2的浓度成正比,其线性范围在0～0.8 mg/L NO-2,摩尔吸光系数为ε284=2.9×104 L/(mol*cm).研究了反应的适宜条件,共存物质的影响,表明该测定方法具有良好的稳定性和选择性.结论: 用紫外分光光度法测定环境水中微量NO-2,结果满意.     

吖啶橙分光光度法测定硫酸软骨素含量

目的建立一种测定硫酸软骨素含量的分光光度分析新方法。方法在pH 4.0的Britton-Robinson(B-R)缓冲溶液中,吖啶橙与硫酸软骨素发生相互作用生成生物超分子复合物。吖啶橙在492 nm处有一特征吸收峰,加入硫酸软骨素后,最大吸收波长不变,但吸收峰强度降低。结果在最佳条件下,溶液吸收度值的降低与硫酸软骨素浓度成线性关系,线性范围为0.04~3.00 mg/L,表观摩尔吸光系数(ε)=6 600 L/(mol.cm),工作曲线为ΔA=0.000 1+0.065 5C(mg/L)(n=8,r=0.998)。结论此法简单、准确、灵敏、选择性好。优化了结合反应的条件,建立了分光光度法测定硫酸软骨素的方法。