HPLC法测定L-(+)-扁桃酸的光学纯度

目的采用HPLC法测定L-(+)-扁桃酸的光学纯度。方法采用Chirlcel OJ-H手性色谱柱,以正己烷-乙醇-三氟乙酸(96∶4∶0.3)为流动相,检测波长220 nm,流速1.0 m L·min-1,柱温30℃。结果 L-(+)-扁桃酸与D-(-)-扁桃酸的分离良好,L-(+)-扁桃酸0.2~1.2×103μg·m L-1与峰面积的线性关系良好(r=0.9998),检测限为0.4 ng(S/N=3),定量限为1.6 ng(S/N=10)。结论所用方法快速、准确、灵敏,适于L-(+)-扁桃酸光学纯度的测定。     

紫草素药理作用研究进展

紫草素是从传统中药紫草中提取的一类萘醌类化合物,具有多种生物学活性,特别是良好的抗肿瘤作用已被大量研究所证实。文章在文献报道的基础上,对紫草素的相关药理作用及其研究进展进行了综述,重点阐述紫草素的抗炎、抗病毒、抗脂肪生成、抗雌激素、抗肿瘤、免疫调节等方面的药理作用。最后对紫草素的研究现状进行概述,并对以紫草素为先导的临床药物研究加以展望。     

Enhanced H2 sorption performance of magnesium hydride with hard-carbon-sphere-wrapped nickel

Magnesium hydride is regarded as one of the most ideal candidates for hydrogen storage, but its relatively high operating temperatures and slow kinetics always hinder its commercial applications. Herein, we first fabricated hard-carbon-sphere-wrapped Ni (Ni/HCS) via a mild chemical method; subsequently, the as-prepared additive was introduced to fabricate an Mg–Ni/HCS composite by using hydriding combustion synthesis. Hard carbon spheres (HCS) effectively inhibited the agglomeration of hydride particles during hydrogen storage cycling; they could also provide active sites to promote the nucleation of Mg-based hydrides. During the hydriding combustion synthesis procedure, in situ-formed Mg₂NiH₄ could induce the absorption of MgH₂, thus triggering its hydrogen properties. Remarkable enhancement in hydrogen absorption properties of the composite was found. The composite absorbed 6.0 wt% H₂ within 5 min at 275 °C; moreover, even at 75 °C, it could still absorb 3.5 wt% H₂. Furthermore, it delivered a high reversible hydrogen absorption capacity of 6.2 wt% and excellent rate capability at 350 °C. It was also demonstrated that the composite could release 6.2 wt% H₂ at 350 °C within 5 min. A rather low activation energy value (65.9 kJ mol⁻¹) for the dehydrogenation of MgH₂ was calculated as compared to that for commercial MgH₂ (133.5 kJ mol⁻¹).

Magnesium hydride is regarded as one of the most ideal candidates for hydrogen storage, but its relatively high operating temperatures and slow kinetics always hinder its commercial applications.     

P53-MDM2界面的肽类及拟肽类抑制剂的研究进展

当前,肿瘤疾病以日益增高的发病率越来越受到人们的重视。抑制P53-MDM2的相互作用已经成为治疗癌症药物设计的重要靶标,通过各种药物筛选手段,研究人员发现了许多肽类及小分子抑制剂。综述近年来国内外关于肽类及拟肽类的P53-MDM2抑制剂的研究进展。     

新生儿ABO溶血病相关性研究

目的 研究母婴血型、孕期血型抗体效价、胎儿性别、胎儿血型、羊水性质、脐血胆红素、脐血溶血三项实验与新生儿ABO溶血病的相关性.方法 分析我院568例ABO血型不合孕妇及其分娩的新生儿病例,根据母婴血型、是否发病来分组分析.结果 母婴血型不同组脐血血清胆红素浓度、新生儿ABO溶血病(ABO-HDN)的发生率及新生儿高胆红素血症发生率均显著高于母婴血型相同组;当孕期血型抗体效价≥1/128时,新生儿患ABO-HDN的几率明显增加;A型血的胎儿更易患新生儿溶血病,胎儿性别及羊水性质与新生儿溶血病的发生无明显相关性.结论 孕期血型抗体效价、胎儿血型、脐血胆红素和脐血溶血三项均与新生儿ABO溶血病有密切相关,根据检测结果可提前预防疾病的发生.     

双指标对蒺藜药材质量控制的方法研究

摘 要 目的： 采用HPLC法结合比色法对蒺藜药材质量进行控制。方法: HPLC法采用色谱柱Welch Ultimate LP-C₁₈(250 mm×4.6 mm,5 μm);流动相：甲醇-水(80∶20);检测波长：203 nm,比色法采用高氯酸法,以蒺藜皂苷元为指标,对蒺藜皂苷元、总皂苷进行含测方法研究。结果:HPLC法和比色法中,蒺藜皂苷元在0.820～7.380 μg和24.600～86.100 μg有良好的线性关系,平均回收率分别为99.3%、99.5%（n=6）。并对18个产地的蒺藜样品中蒺藜皂苷元和总皂苷含量测定。结论: 所建立的方法灵敏、准确、重复性好,可作为蒺藜药材的质量控制方法。     

苯酚-硫酸法测定甘露聚糖肽口服溶液中多糖含量的条件优化

目的:优化苯酚-硫酸法测定甘露聚糖肽口服溶液中多糖含量的反应条件。方法:通过单因素和正交试验,研究各因素对实验结果的影响,并对这些因素进行优化和方法学验证。结果:实验结果表明,苯酚浓度3%、硫酸用量5.0 mL,显色时间15 min,显色温度80℃为苯酚-硫酸法测定甘露聚糖肽口服溶液多糖含量的最佳条件,在此条件下平均回收率为102.7%,其RSD为1.4%。结论:优化后的方法重复性和准确性均有所提高。     

龙马溪组页岩应力敏感性实验评价

X射线衍射和全应力-应变结果表明龙马溪组页岩具有明显的硬脆性特征,破裂前曲线均呈现明显的线弹性变形。在5 MPa和10 MPa围压下,平行层理方向与垂直层理方向岩芯力学性质表现明显不同,平行层理方向的微裂缝由于受到张力作用而导致页岩突然破裂而完全失去承载能力;当围压达到20 MPa时,由于层理微裂缝的闭合,页岩的力学性质表现相似。氮气脉冲压力延迟测试结果表明:平行层理方向取芯页岩的应力敏感性更强,当有效应力增至10 MPa时,垂直层理方向岩芯渗透率下降1~2个数量级,而平行于页岩层理方向岩芯渗透率下降2~3个数量级;方解石充填的天然裂缝可提高岩芯整体渗透率2~3个数量级,且闭合型页岩天然裂缝应力敏感性强于张开型天然裂缝岩芯。     

2型糖尿病患者体脂指标与血压血脂的关系

目的：探讨2型糖尿病患者体质指数（BMI）、腰围（WC）、腰臀比（WHR）、腰围／身高比（WHtR）与血压、血脂的关系。方法调查191例2型糖尿病患者,测量身高、体重、腰围、臀围及血压,计算BMI、WHR、WHtR,测定总胆固醇（TC）、甘油三酯（TG）、高密度脂蛋白（HDL-C）、低密度脂蛋白（LDL-C）,分析上述四种体脂指标与2型糖尿病患者血压、血脂的关系。结果偏相关分析显示：BMI、WC、WHR、WHtR均与收缩压（SBP）独立正相关,其中WHtR相关性最强。BMI、WHtR均与舒张压（DBP）呈正相关。BMI、WC、WHR、WHtR异常组的SBP、DBP、TC、TG、LDL-C水平均较正常组偏高,HDL-C水平较正常组偏低。多元逐步线性回归表示WHtR为TG水平的影响因素。结论各体脂指标（BMI、WC、WHR、WHtR）与2型糖尿病患者的血压及血脂水平的改变有一定的相关性,对于减少2型糖尿病患者发生代谢综合征的风险而言,预防肥胖是至关重要的。     

Vitamin K2 (Menaquinone-7) supplementation does not affect vitamin K-dependent coagulation factors activity in healthy individuals

Background:Vitamin K has long been regarded as a procoagulant drug by physicians, and concerns have been raised with regard to its effects on hemostasis. Although many studies have shown that vitamin K supplementation is safe for thrombotic events, the effect of vitamin K supplementation on the activities of vitamin K dependent procoagulation factors in healthy individuals is not available.Objectives:This study aimed to investigate whether vitamin K2 supplementation at recommended doses affects the activity of vitamin K dependent procoagulation factors in healthy individuals without any anticoagulation treatment.Design:Forty healthy volunteers between 25 and 40 years of age were recruited. Menaquinone-7 (MK-7) was administrated at 90 μg for 30 days. Prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), and blood coagulation factors II, VII, IX, and X activities and Protein induced by vitamin K absence or antagonist-II (PIVKA-II) were measured on days 0 and 30 after MK-7 administration.Results:PT, APTT, and TT showed no significant differences on day 30 when compared with baseline. The activities of coagulation factors II, VII, IX, and X on day 30 showed no significant differences with those at baseline. PIVKA-II levels were unchanged after 30 days of MK-7 supplementation.Conclusions:MK-7 supplementation at recommended dosage does not affect vitamin K-dependent coagulation factors’ coagulation activity, and does not enhance the carboxylation of prothrombin in healthy individuals. This indicated that MK-7 administration does not alter hemostatic balance in healthy populations without anticoagulation treatment.