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41.
目的 :建立测定血浆总同型半胱氨酸的高效液相色谱 (HPLC) 荧光检测分析方法。方法 :用TCEP将血浆中各种形式的同型半胱氨酸 (Hcy)还原成总同型半胱氨酸 (tHcy) ,以光胺作内标 ,巯基特异性荧光衍生剂SBD F对Hcy ,胱胺等含巯基化合物进行柱前衍生 ,然后行HPLC 荧光检测。结果 :本方法所检测的Hcy浓度在 2 .5~ 16 0 μmol·L- 1 范围具有良好的线性关系 (r =0 .9975 ) ,Hcy最低检测限 0 .6 2 5 μmol·L- 1 ,批内变异小于 5 .5 % ,批间变异小于 9.0 % ,平均回收率 98.87%。结论 :本法简便、灵敏、精确、稳定 相似文献
42.
Effect of Prevention and Treatment of Murine Acute Viral Myocarditisand Protection of Lymphoid Organ Atrophy withXinkang Oral Liquid (心康口服液)
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Ithasbeenestablishedthatcoxsackievirusisthepredominantcauseofviralmyocarditisinhuman(1) ,whichisacommondiseaseseriouslyendangerhea 相似文献
43.
3-Methoxytyramine (3-MT) is a minor metabolite of dopamine which is suggested to reflect the turnover and utilization of dopamine. A novel, isocratic HPLC method has been developed which can be used to analyse 3-MT in homogenates of rat brain without the need for additional purification procedures. Furthermore, the coulometric electrochemical detection system is sensitive enough to measure 3 pg of 3-MT (equivalent to 0.6 ng/g tissue wet weight). 3-Methoxytyramine was measured in the striatum and n. accumbens after decapitation and rapid freezing, using 3-methoxy-4-hydroxybenzylamine as the internal standard. The effects of dopaminergic and other drugs on this metabolite were examined using this method. -Methyl-p-tyrosine (200 mg/kg i.v.) produced parallel linear decreases in dopamine and 3-MT in naive rats, but not those pretreated with tranylcypromine (5 mg/kg i.p.). Methamphetamine (0.3–10 mg/kg i.p.) and amphetamine (0.3–10 mg/kg i.p.) both dose-dependently increased 3-MT in naive and tranylcypromine-pretreated rats. In naive animals, 3-MT was not altered by intraperitoneal injection of the dopamine reuptake inhibitors, bupropion (10 mg/kg) and nomifensine (10 mg/kg) or by sibutramine HCl (3 mg/kg), amitriptyline (10 mg/kg), desipramine (10 mg/kg) and zimeldine (10 mg/kg). 3-Methoxy-tyramine was decreased by apomorphine (5 mg/kg i.p.) and also by large doses of the selective D2 antagonist, BRL 34778 (5 mg/kg i.p.) or
-DOPA (50 mg/kg i.p.). The selective D1 antagonist, SCH 23390 (0.1 or 5 mg/kg i.p.) was without effect. In tranylcypromine-pretreated rats, 3-MT was dose-dependently reduced and increased by apomorphine (0.01–5 mg/kg i.p.) and BRL 34778 (0.1–5 mg/kg i.p.), respectively. The drug SCH 23390 (0.1–5 mg/kg i.p.) produced much smaller increases in 3-MT which were probably mediated through the striatonigral pathway. Overall, the data suggest that measurement of 3-MT, after inhibition of monoamine oxidase, is a useful index of the release and utilization of dopamine. However, after substantial and prolonged depletion of dopamine, levels of 3-MT in naive animals are a better index. Also, the formation of 3-MT in naive rats provides a sensitive method for distinguishing between dopamine releasing agents and reuptake inhibitors. 相似文献
44.
Maria P. Panozzo Carlo Fabris Daniela Basso Giuseppe Del Favero Aldo Infantino Attilio Cecchetto Mario Plebani Remo Naccarato 《Clinical and experimental pharmacology & physiology》1993,20(3):185-191
1. The authors investigated the effect of two extrahepatic cholestasis models (one by bile duct ligation and the other by choledocho-jugular fistula) on the hepatic clearance of horseradish peroxidase in male Sprague-Dawley rats divided into four groups. 2. In groups A (n = 5 rats) and B (n = 5), bile duct ligation was performed, while a choledocho-jugular fistula was created in groups C (n = 5) and D (n= 7). A 10 mg intravenous bolus of horseradish peroxidase was injected after 24 h (groups A and C), 48 h (groups B and D) or 1 h (Group E; five sham-operated rats). Serum and bile samples were then serially collected for 2 h. 3. In all groups, serum horseradish peroxidase levels increased soon after injection and then rapidly decreased, the curves being similar. Biliary excretion increased for 30 min and then slowly decreased. The highest horseradish peroxidase biliary concentrations and outputs were found in Group B followed by Group A; both groups had significantly higher levels than Group E. No difference was found between horseradish peroxidase biliary excretion of groups C and D and that of sham-operated rats. 4. When each group was considered separately, sampling times correlated with the corresponding ratios of bile/ plasma HRP. Significant differences were found between the relative slopes of groups A, B and E, but not between those of groups C, D and E. 5. In conclusion, bile duct obstruction greatly affects the plasma-bile transfer of fluid phase markers, such as horseradish peroxidase, while single retention, caused by choledocho-jugular fistula, has no influence. The increased biliary hyperpressure related to the duration of cholestasis may account for the degree of horseradish peroxidase transfer which, in turn, probably depends on an enhanced paracellular passage. 相似文献
45.
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。 相似文献
46.
长泰乐生物保健口服液是一种新型腹泻治疗药物,用该药治疗感染性腹泻45例,与用氟哌酸治疗的对照组比较,结果表明疗效相近,且比后者使用安全。我们认为该药可代替抗生素用于治疗感染性腹泻轻、中型患者,尤其适用于老年、孕妇和儿童。对非感染性腹泻有良好的治疗前景。 相似文献
47.
Reversed-phase high-performance liquid chromatographic method for the assay of 1,4-dioxane in sulphated polyoxyethylene alcohol surfactants 总被引:3,自引:0,他引:3
S. Scalia 《Journal of pharmaceutical and biomedical analysis》1990,8(8-12):867-870
A rapid high-performance liquid chromatographic method has been developed for the assay of 1,4-dioxane in ethoxylated fatty alcohol sulphates. After solid-phase extraction using Bakerbond C18 cartridges, samples were directly analysed on a LiChrospher CH-8 reversed-phase column with UV detection at 200 nm and an acetonitrile-water eluent. Recovery of 1,4-dioxane from the surfactant matrix was 95.7% in the 40 to 120 μg g−1 range. The minimum quantifiable amount was 18 μg g−1. The procedure is simple, reproducible, specific and suitable for routine analyses of commercial surfactants. 相似文献
48.
TAMÁS HENICS & DENYS N. WHEATLEY 《International journal of experimental pathology》1997,78(5):343-354
Hep-2, human epithelial carcinoma cells, and human foreskin fibroblasts (FF9 and FF13) were exposed to either an ultrafiltrate (< 50 kD) of human sera or the weak base, procaine hydrochloride, to induce reversible cytoplasmic vacuolization. The formation of vacuoles was shown not to be due to imbibition of medium. Ultrastructural details obtained from various stages of vacuole formation were compared. In both cases of induction vacuoles were irregular and often appeared membraneless, with little in the way of electron-dense content. They started to form in the perinuclear cytoplasm and progressed towards the periphery. Osmotic stress was not involved since mitochondria remained normal throughout a vacuolization episode.
Vacuoles were often seen in close contact with filamentous structures, and this association remained detectable at late stages of the phenomenon. Fluorescent visualization of F-actin confirmed that the vacuoles were frequently bordered by microfilaments. No major metabolic impairment was apparent in vacuolized cells as judged by protein synthesis measurements, but nuclear fluorescence (DNA content) and forward light scatter (nuclear volume) by flow cytometric analysis suggested late S phase and G2 retardation.1 H-nmr relaxation measurements indicated intracellular water restricted in motional characteristics in vacuolized cells. The possibility of a restricted cytoplasmic phase separation as part of a transient adaptation response is raised, and a hypothesis to explain the findings is discussed. 相似文献
Vacuoles were often seen in close contact with filamentous structures, and this association remained detectable at late stages of the phenomenon. Fluorescent visualization of F-actin confirmed that the vacuoles were frequently bordered by microfilaments. No major metabolic impairment was apparent in vacuolized cells as judged by protein synthesis measurements, but nuclear fluorescence (DNA content) and forward light scatter (nuclear volume) by flow cytometric analysis suggested late S phase and G2 retardation.
49.
50.
MASAAKI KATO MD NAOFUMI KAJIMURA MD MASANORI SEKIMOTO MD TSUYOSHI WATANABE MD KIYOHISA TAKAHASHI MD 《Psychiatry and clinical neurosciences》1998,52(2):262-263
Abstract We tried melatonin treatment in two patients with non-24 h sleep-wake syndrome, who did not respond to treatments by vitamin B12 , bright light therapy, or hypnotics. In one patient, melatonin 5–10 mg improved difficulty in falling asleep and in waking, although it failed to improve the sleep-wake rhythm. In another patient, melatonin 3 mg successfully changed the sleep-wake rhythm from free-running pattern to delayed sleep phase pattern. However, melatonin re-administration after a 4-month drug-free interval failed to improve his free-running sleep-wake rhythm. These results suggest that melatonin acted as a sleep inducer in one patient and as a phase setter in the other, although the effect on the latter patient was transient. 相似文献