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麦冬类中药组织切片计算机三维重建图鉴   总被引:9,自引:0,他引:9  
利用计算机技术实现麦冬类中药组织连续切片三维重建与动态显示,为计算机辅助生药学鉴定和教学提供了新的三维图像技术和研究资料。  相似文献   
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用混合粘合剂碳糊电极测定丁螺环酮   总被引:6,自引:1,他引:5  
用混合粘合剂碳糊电极测定丁螺环酮张正奇,曾鸽鸣,刘传桂,黎艳飞(湖南大学化学化工系,长沙410082)碳糊电极无毒,制作方便,表面更新容易,应用电位范围广,在药物分析中已有应用[1~5]。我们在液体石腊中加入添加剂,组成混合粘合剂,可显著改善电极的检...  相似文献   
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OBJECTIVE: To validate the percentage of time spent below a target value of spontaneous expiratory minute ventilation (< 125 ml/min per kg) during a 2-h period of continuous positive airway pressure (CPAP) via an endotracheal tube (ETT) as a predictor of failed extubation in preterm infants. METHODS: Forty-one infants intubated for at least 24 h, with birth weight between 500 and 1000 g, who were clinically stable and at ventilator setting compatible with an extubation attempt, were studied during a 2-h period of ETT CPAP. Dynamic lung compliance and total lung resistance were measured during a period of quiet breathing, while tidal volume (Vt), respiratory rate and the corresponding spontaneous expiratory minute ventilation values were calculated for the complete recording period of 2 h using a customized computer program. The time each patient spent below the target spontaneous expiratory minute ventilation value was reported as a percentage of the total recorded time (% spontaneous expiratory minute ventilation < 125 ml/min per kg). Extubation failure was defined as the need for reintubation within 72 h. RESULTS: Eleven out of 41 babies (26.8%) experienced failure of extubation (failure group) while 30 infants (73.2%) were successfully extubated (success group). There were no significant differences in dynamic lung compliance and lung resistance between the two groups, but the mean values of respiratory rate and spontaneous expiratory minute ventilation were significantly lower in the failure group than in the success group: 43 (37-56) breaths/min and 240 (160-353) ml/min per kg vs. 53 (28-67) breaths/min and 309 (223-434) ml/min per kg, respectively (p = 0.0129 and p = 0.0039). Moreover, the babies in whom extubation failed spent a longer time below the target value of spontaneous expiratory minute ventilation when compared with successfully extubated babies (p < 0.0001). Percentage of time spent with spontaneous expiratory minute ventilation < 125 ml/min per kg had a larger area than transcutaneous (Tc)PCO2, TcPO2 and pulse oxymetry saturation (SpO2) under the receiver operator characteristic curves. CONCLUSION: The measurement of spontaneous expiratory minute ventilation prior to extubation could be useful in identifying those babies who are not ready for spontaneous ventilation.  相似文献   
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In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications.  相似文献   
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菊叶三七生物碱成分的研究   总被引:8,自引:0,他引:8  
从菊科蒂叶三七植物中分离出六个生物碱,对其中四个进行了鉴定。光谱数据证明:生物碱Ⅰ和Ⅱ分别为已知的千里光碱(senecionine,Ⅰ)和千里光菲灵碱(seneciphylline,Ⅱ),生物碱Ⅲ和Ⅳ为新成分,分别命名为菊三七碱甲(sineciphyllinine,Ⅲ)和菊三七碱乙[(E)-seneciphylline,Ⅳ]。  相似文献   
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Y Niv  C Turani  E Kahan  GM Fraser 《Gastroenterology》1997,112(6):2104-2107
Polycystic kidney disease is an autosomal dominant disease that may be associated with cystic disease of the liver. In women, the cysts may develop early and be more troublesome than in men. Cystadenocarcinoma of the pancreas is uncommon, comprising 1% of primary pancreatic malignancies. This case report is the first to describe a familial association between polycystic kidney disease and cystadenocarcinoma of the pancreas and liver in the English medical literature. A patient with autosomal dominant polycystic kidney disease (ADPKD) and multiple hepatic cysts developed cystadenocarcinoma of the pancreas with multiple malignant liver cysts. The patient's mother, sister, and niece had ADPKD, and the patient's sister also died of pancreatic cystadenocarcinoma. We believe that the development of these two disease entities in which the primary pathology is cyst formation has a genetic association. (Gastroenterology 1997 Jun;112(6):2104-7)  相似文献   
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