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Bilateral ulnar agenesis is a rare abnormality. A total of 36 cases are analyzed: 35 of these are documented in the literature and 1 stillborn male is presented in this study. Most patients had one of the three conditions: Al-Awadi/Raas-Rothschild syndrome, syndrome of ulnar aplasia with split hand/split foot deformity, or the Brachmann—de Lange syndrome. Fifty percent of all cases with bilateral ulnar agenesis were associated with lower limb defects and these cases, for the most part, also belonged to the aforementioned syndromes. Nonskeletal, internal organ malformations were identified in 34% of all patients. Nine patients presented with isolated bilateral ulnar agenesis. The Al-Awadi/Raas-Rothschild syndrome and the split hand/split foot deformity are heritable disorders. There was no evidence for genetic etiology in most of the other cases. Bilateral ulnar agenesis in our fetus was part of the Brachmann—de Lange syndrome with associated cardiac defect, diaphragmatic hernia, and umbilical artery agenesis. 相似文献
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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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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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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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The ability to identify surgical sinus disease using diagnostic nasal endoscopy and coronal CT scanning of the paranasal sinuses is studied prospectively. Fifty consecutive patients with symptoms of chronic sinusitis lacking surgical indications by traditional work-up comprise the patient population. Sixty percent had endoscopic or CT indications for surgery. There was a 90% correlation between endoscopy and CT examination with the combined work-up being more accurate than either modality alone. Functional endoscopic sinus surgery was performed in 18 cases. There were no major complications. Approximately 89% of the postoperative group report significant improvement, with 55.6% reporting total relief of symptoms. A complete endoscopic sinus work-up can often identify surgically correctable sinusitis despite normal routine rhinoscopic and plain-film examination. It is therefore, warranted in those patients with a suggestive history. 相似文献
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CT and MRI are the primary imaging modalities used to evaluate the various regions of the head and neck. From the preceding discussion one can see clearly that the choice of the appropriate imaging modality depends on a number of variables. There is no indisputable "winner" under all anatomical or pathological circumstances. The advantages and disadvantages of CT and MRI in certain clinical settings have been discussed. The information provided will enable one to exercise a rational choice in the selection of imaging modalities. 相似文献