喜树碱多相脂质体包封率测定方法及渗漏的研究

本文应用一阶导数分光光度法,不经分离喜树碱多相脂质体中包封的喜树碱与游离的喜树碱直接测定了喜树碱多相脂质体的包封率,结果为73.±3.4%。同时考查了影响喜树碱多相脂质体渗漏的因素。     

唐松草新碱水溶液的氧化降解动力学研究

本文研究了唐松草新碱在水溶液中的氧化降解动力学。考查了pH值、离子强度、温度和氧含量的影响,水溶液中的氧化降解速率常数由荧光法测定。结果表明,唐松草新碱在过量氧存在下,其氧化降解反应服从假一级反应动力学方程式,速率常数可由下式表示:其速率常数主要受介质的pH值和氧含量的影响,在pH 7.2条件下没有观测到原盐效应。     

脂质体作为生物大分子载体的研究进展

对脂质体作为生物大分子载体，即作为基因物质，生物药物的载体，新型疫苗佐剂和载体，以及生物药物脂质体的给药途径进行了讨论。     

肝动脉注射阿霉素温度敏感脂质体的靶行为和治疗应用的研究

Temperature sensitive liposome entrapped adriamycin was injected into the hepatic artery of Wistar rats bearing implanted hepatic tumor. Two hours after the injection, the liver was heated to 42 ℃ and maintained at that temperature for 6 minutes using a local hyperthermia. The variation in the pattern of the concentration of the liposomal drug in circulation, and the drug distribution in tissues were investigated. Results indicated that adriamycin was released from the liposomes with the drug concentration peaking in circulation at 30 minutes after heating. Following the hyperthermia treatment, the total amount of drug in the liver decreased, while that in the tumor and urine increased. The ¹⁴C labeled liposome track test showed that a parallel relationship between the lipid and the drug was maintained for 8 hours after the hepatic injection, and physiological environment was a determinant of change and existence of liposomal carrier. However, the drug encapsulated in the liposomes can be controlled by hyperthermia to target the tumor. Therapeutic experiments showed that in the group treated with the hepatic artery- injected liposome plus hyperthermia control, the liver tumor growth of the rats administered at 7 days after W₂₅₆ carcinosarcoma implantation on liver was notably inhibited and the life-span of the animal was greatly extended compared with those of aqueous administration groups and ⅳ injected liposome group.     

肝动脉注射阿霉素温度敏感脂质体的制剂研究

自Yatvin等创造温度敏感脂质体以来,许多研究结果证明它是靶治疗的良好载体。Chuang等认为根据荷瘤肝脏的血流分布,设想将温度敏感脂质体通过肝动脉注射滞留于肝动脉,结合人为控制释放脂质体中所包封的药物,有可能提高肝脏肿瘤中的药物浓     

喜树碱前体多相脂体的药理学研究

本文报道了对喜树碱前体(A-CPT)及喜树碱前体多相脂质体(A-CPT-pl)的药理学研究结果。结果表明,A-CPT腹腔注射给药(ip)及经口腔给药(PO),寇氏法求得小鼠的LD50分别为159.3mg/kg及33.7mg/kg,较喜树碱钠盐(CTP-Na)的毒性降低,按最大允许给药容量(0.5ml/10g)ip或PO A-CPT-pl 50mg/kg,在观察期间未见死亡。抑瘤试验结果表明,A-CPT-pl对S180及HepS的抑制率可达74%及82%,可使荷EAC小鼠的生命延长126%;A-CPT对S180及HepS的抑制率可达52%及53%,可使荷EAc小鼠的生命延长54%。肿瘤相伴免疫试验结果表明,每日ip,A-CPT-pl 0.5mg/kg,连续9天,对小鼠肿瘤相伴免疫没有明显影响。     

氨甲喋呤(MTX)多相脂质体化学稳定性的研究

以多相脂质体为载体能增强MTX的化学稳定性。在避光条件下,MTX多相脂质体注射液,25℃时贮存期为4.2年。pH 7的磷酸盐缓冲溶液中的MTX,25℃避光条件下,是以一种新的途径降解。磷酸盐对该反应有特殊的催化作用;而在高温或多相脂质体的存在能防止该反应的发生。     

三波长分光光度法测定喜树碱多相脂质体中喜树碱的含量

本文采用三波长分光光度法测定了喜树碱多相脂质体中喜树碱的含量。安验测得平均回收率为100.3%.实验可以在单光束分光光度计上进行。本方法是测喜树碱含量的新方法,具有快速、准确的特点。     

减肥,从头评说?(一)

胆固醇功过的评价 在国外、国家规定食品的包装上都要印出成分分析表,特别要标出胆固醇的含量,有的食品如麦麸脆片原料本身不含胆固醇.这是众所周知的。但食品厂一定要在盒签的显著地位标上“本品不含胆固醇”,家庭主妇如在超级市场选购“麦麸脆片”时,首先要看看