反相HPLC法同时测定饮料中的两种人造甜味剂

应用反相HPLC法，探讨了同一色谱条件下，食品中安赛蜜，糖精钠、咖啡因及苯甲酸的分离条件，并在此基础上建立了饮料中人造甜味剂安赛蜜、糖精钠的测定方法，取得了满意的结果。在反相C_(18)柱上，使用甲醇-冰乙酸-水（20+3.5+76.5）为流动相，可使安赛蜜、糖精钠、咖啡因，苯甲酸快速而良好地分离，254nm波长下检测，安赛蜜的线性范围为0.002～1.00g／L，最小检测量为0.04μg；糖精钠的线性范围为0.005～1.00g／L，最小检测量为0.08μg，在饮料分析中，外标单点校正法测得数据再用标准添加法处理进而求出的回收率分别为安赛蜜97.6％（n=5,CV=0.74%)、103.5%（n=5，CV=1.l%）、95.l%（n=5，CV=0.73%）；糖精钠97.9%（n=5，CV=0.66％）、99.9%（n=5，CV=0.73%)、102.1％（n=5，CV=0.18%）。本方法分析步骤简便，且检测波长适用于国产单波长检测器。     

用化学计量法研究CO2—n—C7H16系的高压相平衡

测定了在温度３１０．６５Ｋ、３２３．１５Ｋ和压力３．１３～７．５４ＭＰａ条件下的气液平衡数据，实验结果与文献值具有较好的一致性。用ＴＲＫ状态方程对实验所得数据进行关联，取得了较满意的结果。     

The influence of anaesthetic techniques and type of delivery on peripartum serum interleukin-6 concentrations

Background: Interleukin-6 is a pleiotropic cytokine with a wide range of physiological activities. It plays an important role in the immuno-neuro-humoral axis during stress and surgery.
Methods: Serum interleukin-6 in parturients was measured on hospital admission, immediately after birth and 12 and 24 hours later. All parturients had uncomplicated pregnancies, and delivered vaginally without (n=31) or with (n=20) epidural analgesia, or underwent Caesarean section under epidural (n=20) or general (n=10) anaesthesia.
Results: Serum interleukin-6 assayed immediately following Caesarean section was low, but peaked 12 hours later, irrespective of the anaesthetic technique or other foetomaternal characteristics. Patients who delivered vaginally showed the highest interleukin-6 levels immediately after delivery. These were positively correlated with serum interleukin-6 on admission and duration of labour. Serum interleukin-6 was significantly higher in parturients who had epidural analgesia, and was significantly lower in those receiving intravaginal prostaglandins compared to those without prostaglandins.
Conclusion: The interleukin-6 response after Caesarean section can be explained by a generalized acute phase response to surgery, with no anaesthetic, maternal or neonatal interference. The rapid increase in peripartum serum interleukin-6 levels after vaginal delivery reflects, in part, cervical ripening or labour, their physiological triggers and psychological or physical stress. Regional anaesthesia, duration of labour and exogenous prostaglandin administration can modulate the peripartum interleukin-6 response and subsequently the physiological effects of this cytokine.     

手性液晶的研究——Ⅸ．联苯羧酸酯类

合成了文题所述的十三个手性液晶化合物。经元素分析和红外光谱分析确证了其结构，并进行了相态、相变温度和电滞回线的测定，证实其为铁电液晶。     

反相高效液相色谱法测定牛黄类中成药中胆汁酸的含量

反相高效液相色谱法测定牛黄类中成药中胆汁酸的含量倪坤仪，王建，陈健，郁建，屠树滋（中国药科大学２１０００９）含牛黄的中成药种类很多，在医疗中具有广泛的用途。中药牛黄中主要成分为胆汁酸和胆红素。本文主要研究用ＨＰＬＣ法测定牛黄以及含牛黄中成药中胆汁酸的...     

Two-step hard acid deprotection/cleavage procedure for solid phase peptide synthesis

A new two-step deprotection/cleavage procedure for t-butoxycarbonyl (Boc) based solid phase peptide synthesis is reported. First the protective groups are removed from 4-(oxymethyl)-phenylacetamidomethyl (PAM) resin attached peptide with the weak hard acid, trimethylsilyl bromide-thioanisole/trifluoroacetic acid (TFA). In the second step, the peptide is cleaved from the resin with a stronger hard acid such as trimethylsilvl trifluoromethanesulfonate in TFA or with HF. The method is also shown to deformylate Nⁱⁿ-formyltryptophan moiety efficiently. The usefulness of this procedure for practical solid phase peptide synthesis is demonstrated by comparison with other deprotection methods in the synthesis of urotensin II and human endothelin.     

健康人视动性眼球震颤的研究

用微处理机(单板计算机)实时分析了视动性眼震,提取了10项参数,其中9项参数得出正常值,可作为评定视动性眼震之参考。各项参数间均有相关,整体评定,可提高诊断水平。将平均慢相速度、快相波辐和累积快相波辐、慢相时间等4项参数分别用计算机处理和人工处理,把两种处理结果进行t检验,无显著差异(P值均>0.05)。将计算机与人工计算的眼震频率进行比较,两者符合率达96.7％以上。采用微处理机可显著提高工效。     

Simplified determination of serum cholesterol sulfate by gas-liquid chromatography combined with cyclohexylsilane-bonded phase column purification

Summary A new gas-liquid chromatographic (GLC) determination of cholesterol sulfate (CS) and dehydroepiandrosterone sulfate (DHEAS) for a biochemical diagnosis of recessive X-linked ichthyosis (RXLI) is described. Although the GLC method for determination of CS is known to be more sensitive than the thin layer chromatographic (TLC) method, the former method has not been widely employed because of its complicated pre-purification steps. The present method allows us to measure the serum levels of CS and DHEAS without tedious purification steps such as multiple conventional column chromatography and preparative thin layer chromatography. Sulfated steroids are rapidly purified with a commercially available mini disposable cyclohexylsilane-bonded phase (CH) column, CH BOND ELUT, and the purified steroids after desulfation are converted to water-resistant tert-butyldimethylsilyl ether derivatives for the GLC analysis on dual 2 m glass columns packed with 2% XE-60 on Chromosorb W.By the present method, serum CS concentrations in RXLI patients were shown to be about 10 times higher than those in patients with ichthyosis vulgaris, carriers of RXLI, and healthy subjects. This method is more suitable not only for a biochemical diagnosis of RXLI but also for studies on the metabolism of sulfated steroids than the previous time-consuming GLC methods.