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21.
Background The skin microdiallysis technique makes it possible to measure histamine release in intact human skin in vivo directly. In this study we have used the microdialysis technique to characterize histamine release by codeine after intracutaneous injectioin and following skin challenge by a novel atraumatic delivery technique. Objective The purpose of the study was to compare histamine release in human skin by codeine. delivered by an intraprobe drug delivery system (IPD) and intracutaneous injections (ICT), with respect to dose-response relations, kinetics of histamine appearance and decay, corelations between histamine release and skin respones, and reproducibility. Methods Hollow dialysis fibres were inserted intradermally in 12 healthy subjects. Twelve fibres were inserted in each subjects, six fibres in each arm. Each fibre was perfused at a rate of 3 μL/min, and samples were collected in 2 min fractions. By the IPD technique, codeine was administrered to the skin by adding codeine to the perfusion medium. Sequential IPD challenges were performed in one arm. and ICTs were done on the other arm. Results Sixfold serial dilutions of codeine (0.01-3 mg/mL) caused a significant doserelated histamine release by ICT and IPD. Peak histamine release was found within the first 4 min after skin challenge by ICT and IPD, followed by a fast decline with a dialysate histamine half life of approximately 2-3 min. Peak hisamine release was linearly correlates with cumulative release of the 20 min sampling period, and histamine release correlated with weal soze. The coefficient of variation on peak histamine releae was 18.9% and 4.8% for codeine ICT and IPD, respectively. Conclusioin We have described in detail codeine-induced histamine release in intact human skin in vivo by the microdialysis technique. It was possible to administer codeine atraumaticallyl to the skin by intraprobe delivery. The skin microdialysis codeine atraumaticallly to the skin by intraprobe delivery. The skin microdialysis technique opens up possibilities for measurement of infllammatory mediators release in normal and diseases skin, and it will be possible to deliver immunopharmacologically active drugsto the skin by intraprobe delivery. 相似文献
22.
When administered systemically, glucose attenuates deficits in memory produced by several classes of drugs, including cholinergic antagonists and opiate agonists. Glucose also enhances memory in aged rats, mice, and humans. In addition, glucose ameliorates age-related reductions in paradoxical sleep. Because deficits in paradoxical sleep are most marked in those individual aged rats that also have deficits in memory, treatments which improve one of these functions may similarly improve the other. The present experiments show that glucose attenuates deficits in paradoxical sleep and memory after atropine administration, with similar dose-response curves for both actions. In the first experiment, rats received saline, atropine (1 mg/kg), glucose (100 mg/kg) or combinations of atropine + glucose (10, 100, 250, and 500 mg/kg) 30 min before assessment on a spontaneous alternation task. In the second experiment, 3-h EEGs were assessed for spontaneous daytime sleep in rats administered saline, atropine (1 mg/kg), glucose (100 mg/kg) or combinations of atropine + glucose (10, 100 and 250 mg/kg). In both experiments, glucose significantly attenuated deficits at an optimal dose of 100 mg/kg. A third experiment assessed blood glucose levels after injections of atropine + glucose (100 mg/kg) and determined that blood glucose levels were similar to those produced by other treatments which enhance memory. These results are consistent with the view that paradoxical sleep and at least one test of memory are similarly influenced by atropine and glucose. 相似文献
23.
LightCycler实时监测PCR定量分析血清HBV DNA 总被引:2,自引:0,他引:2
目的 检验LightCycler实时监测PCR(real-time detection PCR,RTD-PCR)对血清中HBV DNA定量检测的灵敏性和可重复性,探讨HBV血清标志物与HBV DNA定量的关系。方法 HBV定量按深圳匹基公司乙肝PCR荧光检测试剂盒使用说明,对乙肝标志物已明确的773例血清中HBV DNA定量结果进行统计分析。结果 实时监测PCR对血清中HBV DNA定量检测的灵敏性高,可检测低至1000拷贝/ml血清;可重复性好,批间误差<20%;各种标志物类型的血清HBV DNA含量分布情况表明,HBV血清标志物中HBeAg与HBV DNA含量有明显的关系,一般HBeAg阳性血清HBV DNA含量较高,但也有相当一部分例外。结论 LightCycler实时监测PCR对血清中HBV DNA定量检测灵敏性高可重复性好;仅根据HBV血清标志物往往不能确定乙肝患者HBV DNA复制水平的高低,HBV DNA定量检测具有十分重要的临床意义。 相似文献
24.
李阳春 《南通大学学报(哲学社会科学版)》2002,18(2):117-120
八十年代初中期 ,中国戏剧积极拓展我国传统戏剧的时空观、写意性特征 ,大胆借鉴西方现代戏剧的荒诞化、意象性技巧 ,出现了探索创新、多元发展的崭新局面。其中对“三一律、一堵墙”戏剧观的突破 ,运用意识形象外显人物的内心世界 ,嫁接多种艺术手段将现实时空转化为艺术时空 ,是新时期戏剧艺术探索最突出的三项成就。而过分强调形式技巧 ,脱离观众欣赏习惯 ,致使演出市场萎缩 ,观众锐减 ,无疑是新时期戏剧艺术探索中面临的最大困顿。 相似文献
25.
Non-invasive tear break-up time (NITBUT) has been proposed as a measure of tear film integrity which is superior to the more commonly used tear break-up time (TBUT), since it does not alter the volume or the physicochemical properties of the tear layer by the addition of fluorescein. We measured NITBUT by measuring the time taken for distortions or discontinuities to appear in the reflected image of a grid pattern which covered about 80 per cent of the corneal surface. NITBUT measures were made 100 times on seven Hong Kong Chinese subjects with up to 20 consecutive measures being made on a single day. We also measured NITBUT on one occasion on an unselected population of 52 Hong Kong Chinese subjects. NITBUT shows a skewed distribution in all subjects, with many shorter values and some extremely long values. There are statistically significant variations in NITBUT from day to day, and from subject to subject. The group of 52 subjects also had a skewed NITBUT distribution with many short values and some very long values. The arithmetic mean does not adequately represent NITBUT data, either for individual subjects or for this group of subjects. As many as five to eight measures may be necessary to gain a stable estimate of the NITBUT and stability of the measure is improved if extreme values are omitted. We recommend the use of nonparametric statistics to compare NITBUT values from day to day in or between subjects. 相似文献
26.
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
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29.
Background: Melatonin is gaining popularity as a sedative agent with children. This study sought to characterise this practice more precisely as well as examine aspects of its safety and efficacy in order to develop treatment guidelines.
Method: Postal surveys of two groups of psychiatrists: generic child psychiatrists and psychiatrists who regularly treat learning disabled children.
Results: Both groups (all of the specialists and 81% of the non-specialists) reported regular but not frequent use of melatonin in their usual practice, mostly for night-settling sleep problems refractory to behavioural modification strategies, commonly in the context of neurodevelopmental disability (especially autism). Treatment was described as being 'usually successful' and side-effects were highly infrequent and mild in nature. Variations in most prescribing practices were identified (dosage, timing).
Conclusions: Melatonin appears to represent a useful and relatively safe drug when used in specific circumstances; however, the evidence-base underpinning its use, particularly over the long-term, remains modest. Thus caution and clinical audit of practice is required. 相似文献
Method: Postal surveys of two groups of psychiatrists: generic child psychiatrists and psychiatrists who regularly treat learning disabled children.
Results: Both groups (all of the specialists and 81% of the non-specialists) reported regular but not frequent use of melatonin in their usual practice, mostly for night-settling sleep problems refractory to behavioural modification strategies, commonly in the context of neurodevelopmental disability (especially autism). Treatment was described as being 'usually successful' and side-effects were highly infrequent and mild in nature. Variations in most prescribing practices were identified (dosage, timing).
Conclusions: Melatonin appears to represent a useful and relatively safe drug when used in specific circumstances; however, the evidence-base underpinning its use, particularly over the long-term, remains modest. Thus caution and clinical audit of practice is required. 相似文献
30.
Among British-qualified doctors of 1974 and 1977, about 80% held postgraduate qualifications of some kind. The commonest qualifications were DRCOG, MRCP and MRCOG. There were considerable differences between medical schools in the numbers of qualifiers taking various examinations. Apart from the MRC Psych, DRCOG and Family Planning Certificate, qualifications were more commonly held by men than women. Tables show the type of work being done 9-13 years after leaving medical school by holders of various postgraduate qualifications; e.g. 60% of MRCP holders were working in medicine or a medical specialty and 84% of FRCS holders in general surgery or a surgical specialty. Discussion deals with the plurality, specificity, variability, perceived necessity, sufficiency, international utility and career significance of British postgraduate qualifications. 相似文献