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SUMMARY A case congenital dislocation of both knees and dislocation of the left hip in an infant whose mother had a chronic amniotic fluid leakage after mid-trimester amniocentesis. 相似文献
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R C Hardie 《The Journal of neuroscience》1991,11(10):3079-3095
A preparation of dissociated Drosophila ommatidia is described that allows single-channel and whole-cell patch-clamp analysis of currents in identified sensory neurons. Three distinct classes of voltage-sensitive potassium conductances are characterized; all were detected in distal parts of ommatidia from sevenless mutants and hence in one cell class (R1-6 photoreceptors). Rapidly inactivating A-channels (IA), coded by the Shaker gene, were isolated in multichannel patches from adult flies. While showing similar kinetics to muscle A-channels, they differ from previously characterized wild-type Shaker channels in having a much more negative voltage operating range, being half-inactivated at approximately -70 mV. Two delayed rectifier conductances were characterized in whole-cell recordings from pupal photoreceptors. The most commonly encountered class (IKs) is similar to previously reported delayed rectifier conductances in Drosophila. It inactivates slowly (time constant, approximately 500 msec) and is half-inactivated at approximately -40 mV. A more rapidly inactivating delayed rectifier (IKf) was detected in approximately 30% of cells; it is half-inactivated at approximately -80 mV. Both IKs and IKf are blocked by 100 microM quinidine. Neither are greatly affected by 4-aminopyridine, which blocks IA at 1-5 mM. None of the three conductances was calcium dependent, nor were they obviously affected by the eag mutation, which affects K channels in muscle. The developmental profile of the channels is the inverse of that described in muscle. Both IKs and IKf are present at the earliest pupal stages examined (approximately 60 hr), but IA was only first detected at approximately 76 hr.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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高效液相色谱法测定右旋儿茶素血浆浓度及药代动力学参数 总被引:1,自引:0,他引:1
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。 相似文献
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Howard B Moss Thomas L Hardie John P Dahl Wade Berrettini Ke Xu 《Neuropsychopharmacology》2007,61(8):974-978
BACKGROUND: Some studies have associated alcohol dependence (AD) with the human serotonin (5-HT)(1B) receptor (HTR1B). This investigation explored the functional responsivity of HTR1B in abstinent AD men using a sumatriptan challenge, while measuring genetic heterogeneity in the HTR1B promoter. METHODS: Abstinent AD men (n = 27) and abstinent men without any alcohol use disorder (n = 19) were administered 6 mg of sumatriptan succinate, subcutaneously. Plasma samples collected over the following 2 hours were assayed for growth hormone (GH) concentrations. His DNA was genotyped for the A-161T and T-261G polymorphisms of the HTR1B promoter and diplotypes determined. RESULTS: Integrated GH responses were predicted by interactions of AD and promoter diplotypes, as well as subject ethnicity. The final model accounted for nearly 35% of the variance in GH responses. Post hoc evaluation revealed that AD was associated with a blunting of GH secretion only among individuals with the most common HTR1B diplotype (TT/TT). CONCLUSIONS: A blunting of GH responses in abstinent AD men was observed only among those with the most common HTR1B promoter diplotype. Less common promoter diplotypes appeared protective. Controlling for genetic background is a useful augmentation of case-control pharmacological challenge strategies designed to elucidate the psychobiology of AD and other complex disorders. 相似文献
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石杉碱甲类似物的研究II.N-甲基吡啶酮石杉碱甲类似物的合成 总被引:4,自引:1,他引:3
石杉碱甲(1)是从中草药石杉属植物千层塔(Lycopodium serratum Thunb.)中分得的一种高效可逆的乙酰胆碱酯酶抑制剂,临床试验证实它对早老性痴呆症有显著疗效。本文报道N-甲基吡啶酮石杉碱甲类似物2和3的合成。2-甲氧基-5-甲氧羰基-11-亚甲基-5,9-甲撑环辛-7-烯并吡啶(9)在乙腈中用三甲基氯硅烷和碘化钠选择性脱保护以定量的产率得吡啶酮10,再用甲醇钠和碘甲烷甲基化得N-甲基吡啶酮11,11经碱性水解,Curtius重排和氨基的脱保护得N-甲基吡啶酮石杉碱甲类似物2。通过类似的途径从中间体2-甲氧基-5-甲氧羰基-7-甲基-11-酮-5,9-甲撑环辛-7-烯并吡啶(14)合成了类似物3。类似物2和3的乙酰胆碱酯酶抑制活性均低于天然石杉碱甲。 相似文献
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