反相高效液相色谱法测定洛氟沙星的血药浓度

采用反相ＨＰＬＣ法测定洛氟沙星的血药浓度，血浆样品用二氯甲烷在ｐＨ７．０条件下提取后进样，流动相为１０ｍ ｍｏｌ／Ｌ磷酸二氢钾－１０ｍ ｍｏｌ／Ｌ溴化四丁铵－乙腈－三乙胺（４５：４４：１０：１，磷酸调节ｐＨ２．８），紫外检测器λ＝２９５ｎｍ，最低检测浓度１０μｇ／Ｌ，线性范围：０．１￣６．０ｍｇ／Ｌ，ｒ＝０．９９９９，日内ＲＳＤ为１．３８％￣３．４２％，日间ＲＳＤ为１．１１％￣２．８９％。     

关附甲素对豚鼠乳头肌动作电位最大除极速度的频率依赖性抑制作用

应用标准微电极技术，研究了关附甲素对豚鼠右心室乳头肌动作电位最大除极速率(V_max)的频率依赖性抑制作用(RDB)，并与美西律，奎尼丁，劳卡尼进行了比较. 在相同刺激间隔(300 ms)，产生50%左右RDB的药物浓度下，美西律的RDB开始最快，其第2个V_max所产生的抑制已占RDB的64%，奎尼丁，劳卡尼和关附甲素的RDB开始速率常数分别为每个动作电位0.165, 0.076和0.136. 美西律，奎尼丁，劳卡尼和关附甲素产生RDB的恢复时间常数分别为1.4, 9.0, 18.2和44.0 s，而且它们的恢复时间常数是不依赖于药物浓度而变化的，结果提示，关附甲素是一个慢动力学钠通道阻滞剂.     

Effects of 5-Hydroxytraptamine on Aggregation,Release Reaction and Mobilization of Cytosolic Free Calcium Concentration in Rabbit Normal and Washed Single Platelets

In rabbit platelet rich plasma (PRP), 5-hydroxytraptamine (5-HT,0.03～3μmol/L) induced decrease in light transmission (DLT) dose-de pendently with centralization, as revealed by electron microscopy. However, 5-HT did not induced platelet aggregation and release reaction. 5-HT-induced DLT was inhibited by methysergide (0.3～30μmol/L), indomethacin (0.3～10μmol/L) and PGE_1 (0.01～0.3μmol/L) in a dose-dependent manner, but not EGTA(0.3～3mmol/L). Collagen(Coll), arachidonic acid (AA), adenosine diphosphate (ADP) and a stable thromboxane A2 analoge(STA_2) also induced DLT before aggregation by themselves, which was also inhibited by PGE_1, but not inhibited by EGTA except for Coll However,Coll-, AA-, STA_2-and ADP-induced DLT were reduced by pretreatment of PRP with 5-HT dose-depen-dently. The duration of DLT by Coll and AA were decreased from 151.4±5.93 sec and 15(?)38±0.60sec to 45.44±4.04 sec and 9.00±1.25 sec respectively ((?)±s(?) P<0.01), but not by ADP and STA_2, 3μmol/L of ADP-and 0.3μmol/L of STA_2-induced aggregation which was not accompanied with release reaction were enhanced by 5-HT pretreatment, but in those (Coil 5μg/ml, AA 100～200μmol/L and STA_2 1～3 μmol/L) with release reaction, the amount of adenosine triphosphate(ATP)were suppressed significantly (P<0.001) by 5-HT pretreatment without the effect on the magnitude of aggregation, The mobilization of cytosolic free calcium concentration ([Ca~(2+)]i) was observed after 5-HT treatment in single washed platelet, the results indicated that the basic level of [Ca~(2+)] i was 64.78±3.24nmol/L and this level was increased dose-dependently and significantly at 30 sec after administration of 5-HT and the time of peak value of [Ca~(2+)] i was at 90～100 sec.The similar time courses of suppression of ATP released during aggregation, in cases of Coll(5μg/ml), AA (200μmol/L) and STA_2(3μmol/L), by 5-HT were also found in the present experiment.     

Effects of intravenous L-acetylcarnitine on retinal oscillatory potentials

L-acetylcarnitine is a compound with cholinergic properties and putative action on the visual system and the glucose metabolism. Ten healthy, emmertropic volunteers (age range: 21 to 28 years) were studied. Each subject was administered 5, 10, and 30 mg/kg acute intravenous doses of L-acetylcarnitine and matching placebo. Retinal oscillatory potentials to full-field flash stimulation were recorded before and 30, 60, and 120 min after administration. A systematic reduction of the implicit time of the P2 and N2 oscillatory potential components was observed after administration of the 10 and 30 mg/kg doses: significant changes were not evident at the 5 mg dose or after placebo. The latency reduction was significantly correlated with the postdrug increment of the L-acetylcarnitine plasma concentration. No other systematic modification in latency of amplitude was observed.The results were presented in part at the XXV I.S.C.E.V. Symposium, Sarasota (Florida), April 26–30, 1987.     

液膜法提取发酵液中的苯丙氨酸 Ⅱ.操作工艺条件

从芫花Ｄａｐｈｎｅ ｇｅｎｋｗａ条的乙酸乙酯可溶部分分到３个结果性化合物，借助于波谱分析手段推断出Ⅱ为西瑞香素，Ⅲ为ｄａｐｈｎｏｄｏｒｉｎ Ｂ。     

格列齐特片的人体药代动力学及其相对生物利用度研究

建立了ＨＰＬＣ方法测定人血浆中格列齐特的药物浓度。采用反相柱和乙腈甲醇水（１５∶４５∶４０）（ｐＨ３．５）作为流动相，格列吡嗪作为内标，检测波长为λ２２８ｎｍ。研究了１０名健康受试者随机交叉口服某药厂研制的格列齐特片剂和标准参比制剂格列齐特片８０ｍｇ后，用ＨＰＬＣ法测定血浆中药物浓度。估算某药厂研制的格列齐特片和标准参比制剂的生物半衰期分别为９．９２±３．５２ｈ和９．９７±３．４５ｈ，达峰时间分别为３．５０±０．７１ｈ和３．８５±２．２６ｈ，峰浓度分别为５．７８±０．９５μｇ／ｍｌ和６．１４±１．５６μｇ／ｍｌ。以标准参比制剂为对照，用面积法估算的某药厂研制的格列齐特片剂的相对生物利用度为１．０１±０１１。经方差分析和双单侧检验两制剂的ＡＵＣ０４８和ＡＵＣ０∞及Ｃｍａｘ，结果表明两制剂生物等效。     

福建产舟山眼镜蛇毒细胞毒素的快速分离纯化及鉴定

目的 从舟山眼镜蛇毒中分离纯化细胞毒素(CTX)，并鉴定其理化性质。方法 采用SP—Sephadex C-25阳离子交换色谱及Sephasil Peptide C18反相高效液相色谱法从舟山眼镜蛇毒中分离纯化CTX，SDS—PAGE(Tris—Tricine系统)鉴定纯度，Edman降解法测定N端氨基酸序列。结果 粗毒经阳离子交换色谱，得到14个蛋白峰，其中第X～XⅢ峰具CTX活性；再分别经反相色谱纯化，得到4个CTX．总得率为32.48％；SDS—PAGE显示为均一蛋白，分子量依次为：7．28，7．33，7．24和7．38kD；测定它们N端20个氨基酸序列。结论 采用阳离子交换和反相高效液相色谱可快速、高效地从眼镜蛇毒中获得4个CTX纯品。     

组织工程心肌补片对黑山羊陈旧性心肌梗死心功能和建立侧支循环的影响

目的探讨自体骨髓间充质干细胞(m arrow m esenchym a l stem ce lls,M SC s)-小肠黏膜下层(sm a llin testina l subm ucosa,S IS)构建的组织工程心肌补片,移植于陈旧性心肌梗死区后对心功能及缺血区建立侧支循环的影响。方法将已建立急性心肌梗死模型后6周的黑山羊16只,随机分为实验组和对照组,实验组抽取自体骨髓,经体外分离M SC s,进行培养、传代,以第3代细胞行5-B rdU标记并与S IS支架材料复合培养5 d,制备M SC s-S IS组织工程心肌补片。将其缝合至陈旧性心肌梗死区;对照组仅行假手术处理。于植入后6周,采用超声心动图观察两组动物心功能变化,数字减影血管造影选择性左冠状动脉造影观察缺血心肌侧支循环的建立。结果术后6周实验组及对照组:心博出量、左心室射血分数分别为42.81±4.91、37.06±4.75 m l和59.20%±5.41%和44.56%±4.23%,组间差异均有统计学意义(P<0.05);左心室舒张末期容积、左室收缩末期容积分别为72.55±8.13、83.31±8.61 m l和29.75±5.98、46.25±6.68 m l,组间差异均有统计学意义(P<0.05);左心室舒张功能各项指标分别为:E峰最大速度分别为54.85±6.35 cm/s和43.14±4.81cm/s(P<0.01);A峰最大速度分别为52.33±6.65 cm/s和56.91±6.34 cm/s(P>0.05)。超声心动图显示对照组左室腔扩张明显,室壁运动明显减弱,梗死区呈瘤样扩张,局部室壁反常运动;实验组左室腔明显小于对照组,室壁运动较对照组强,心尖梗死区扩张不明显。选择性左冠状动脉造影见实验组左冠状动脉前降支远端与回旋支间明显侧支循环建立。结论M SC s-S IS构建的组织工程心肌补片移植于黑山羊陈旧性心肌梗死区后侧支循环建立,心功能有明显改善作用。     

中等强度冲击波负压暴露对豚鼠耳蜗毛细胞游离钙浓度的影响

目的:观察实验性冲击波负压(BUP)暴露对豚鼠耳蜗外毛细胞内游离钙浓度([Ca2 ]i)的影响。方法:在激光共聚焦显微镜下,用钙敏荧光探针Fluo-3作为指示剂,观察豚鼠暴露中等强度实验性BUP后耳蜗外毛细胞[Ca2 ]i的变化。结果:中等强度BUP暴露后8 h,至暴露后24 h和3 d稍有回落,但仍高于正常对照组。上述这些变化与听性脑干反应阈值的升高是一致的。结论:豚鼠暴露中等强度性BUP可引起耳蜗外毛细胞内[Ca2 ]i的明显增高,且可能是听功能损害的主要原因之一。