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61.
The purpose of our research was to determine the effects of superparamagnetic iron oxide on MR imaging of the portal venous system. Eight piglets were examined in deep anaesthesia and respiratory arrest using a time-of-flight magnetic resonance fast low angle shot, two-dimensional angiography sequence at 1.5T. MR angiograms were acquired precontrast and after intravenous administration of a cumulative dose of 10, 20 and 40 μmol/kg SHU 555A, a superparamagnetic iron oxide contrast agent for MR imaging with a particle size of 60 nm. For each dose, two subsequent sets of scans were obtained and reconstructed by a maximum-intensity-projection algorithm. Hepatic parenchymal and portal venous signal intensities were measured, and portal vein contrast calculated for each set of scans. All examinations were visually rated as to portal vein contrast and homogeneity by two blinded observers. Receiver operating characteristics of both observers were analyzed. The contrast agent reduced hepatic parenchymal signal in a dose-dependent way. After a cumulative dose of 10 μmol iron oxide, hepatic parenchymal signal intensity decreased to 63 ± 6% (average of measurements at 4 and 14 minutes, mean ± standard error of the mean), after 20 μmol to 24 ± 3%, and after 40 μmol to 12 ± 1% of control. Intra-vascular signal in the left main portal vein branch increased to 117 ± 6%, 127 ± 10%, and 133 ± 9% of control, respectively. The contrast-to-noise ratio of the portal vein improved (521 ± 90%, 891 ± 178%, and 995 ± 201% of control in the left portal vein main branch). Intravascular signal intensities increased slightly. The combined effect improved contrast of the portal vein stem and its branches. Receiver operating characteristics analysis documented dose-dependency of contrast medium effects on portal venous contrast and intravascular homogeneity. Visual rating also indicated a positive effect on portal venous contrast. The superparamagnetic iron oxide agent improved portal venous contrast with surrounding hepatic parenchyma in this normal animal model, and could potentially result in more accurate diagnosis of portal venous pathology.  相似文献   
62.
考察了各类添加剂在不同浓度、温度及不同基础油中的泡沫倾向,并测定了这些条件下体系的表面张力。从表面化学角度解释了添加剂对泡沫性质的影响,并通过对抗泡剂配伍性能的研究,验证了消泡机制:抗泡剂须具备高的表面活性才能吸附于泡膜表面,降低泡膜的表面粘弹性,改变膜的流变性能,从而起消泡作用。  相似文献   
63.
The Kasabach-Merritt syndrome is characterized by thrombocytopenia and localized coagulopathy associated with a hemangioma. Most techniques applied to eradicate the tumor or accelerate its involution (surgery, radiation therapy, embolization) are invasive and require transfusion of large amounts of blood products. In some cases, medical treatment is the only alternative. Efficacy of steroids and antifibronolytic agents has already been described, but even this approach is associated with the administration of blood products. We report two cases of infants with Kasabach-Merritt syndrome associated with cardiac and hepatic hemangiomas. At admission, both had signs of cardiac failure. They were successfully treated with prednisone and epsilon-aminocaproic acid (EACA). Blood products were not required once the diagnosis was made. These observations have important implications for the management of patients with Kasabach-Merritt syndrome because they show that even in severe cases blood transfusions can be avoided by the use of prednisone and EACA.  相似文献   
64.
短效催眠药唑吡坦和三唑仑对人体前庭功能的影响   总被引:3,自引:1,他引:2  
目的 :探讨两种短效催眠药唑吡坦和三唑仑对人体前庭功能的影响 ,为在应急条件下对飞行员服用该药提供试验依据。方法 :8名受试者 ,采用三阶段交叉双盲给药设计方法 ,分别交叉服用三唑仑 (0 .2 5mg)、唑吡坦 (10mg)、安慰剂 ,每次间隔 1周 ,在服药前 1h及服药后1、2、3、4、6、8、10h分别进行一组前庭功能测试 ,包括视动性眼震 (OKN)、前庭眼动反射 (VOR)、前庭眼动反射固视抑制 (VOR -Fix)、视前庭眼动反射 (VVOR)。结果 :与安慰剂组比较 ,服用唑吡坦和三唑仑后均能显著降低VOR、OKN、SPT增益 ,在服药 2h后降到最低〔VOR :(0 .5 1± 0 .0 4 ) ,(0 .5 2± 0 .0 5 )vs (0 .6 7± 0 .13) ;OKN :(0 .32± 0 .0 2 ) ,(0 .6 2± 0 .0 6 )vs (0 .82± 0 .0 7) ;SPT :(0 .71± 0 .14 ) ,(0 .6 6± 0 .0 6 )vs (0 .93± 0 .0 3)〕。其中唑吡坦对OKN增益的降低要强于三唑仑 ,但这种影响持续时间不长 ,在服药 6h后即消失。两种短效催眠药对VVOR增益、SPT相位及VOR -Fix均无明显影响。结论 :唑吡坦及三唑仑对人体前庭功能具有一定的影响 ,但这种影响持续时间较短 ,对人体的空间定向及平衡能力无残留后遗效应  相似文献   
65.
Despite improvements in supportive care, the mortality and morbidity of asthma remain constant. The risks and incidence of morbidity related to barotrauma remain high in patients that require mechanical ventilation. The authors present three alternative strategies including the inhalation of anaesthetic agents, helium/oxygen ventilation, and extracorporeal membrane oxygenation which may be beneficial when 'conventional therapies' fail in the intubated patient with status asthmaticus.  相似文献   
66.
本研究通过体外培养5种人癌细胞(肝癌、胃癌、肺癌、Hela细胞和咽癌)和小鼠移植性肿瘤实验,证明了红景天素可明显抑制3种癌细胞的生长增殖,可提高荷瘤小鼠的存活率,延长其生存期,抑瘤率在50%以上。结果提示红景天素对体外培养3种癌细胞和小鼠S180。细胞均有一定的抑制作用。  相似文献   
67.
The effects of sedative-hypnotic doses of propofol on respiratory drive and pattern have not yet been extensively described. Repeated small boluses of propofol (0.6-0.3 mg.kg-1) were administered to ten ASA I patients undergoing carpal tunnel release using regional anaesthesia. Airway pressure, capnography and pneumotachography were continuously recorded. With respect to basal values, no significant variations of respiratory rate, minute volume, tidal volume, inspiratory and expiratory time, total expiratory cycle, Ti/Ttot, TV/Ti, P0.1, EtCO2 and blood gas analysis were observed. Low doses of propofol, to maintain conscious sedation of light sleep, have not been shown to cause respiratory depression.  相似文献   
68.
The introduction of second-generation microbubble ultrasound contrast agents and the development of contrast specific ultrasound techniques have improved the ability of contrast enhanced ultrasound in detecting and characterising liver lesions, offering new perspectives for its exploitation in clinical hepatology. Indeed, several studies have demonstrated a high diagnostic accuracy in focal lesion characterisation (85-96%) in patients either with or without underlying chronic liver disease. This review article describes the basic principles of contrast enhanced ultrasound, defines the different vascular features of benign and malignant liver lesions, and assesses its clinical impact in different clinical scenarios, according to the guidelines of the European Federation of Societies for Ultrasound in Medicine and Biology, contrast enhanced ultrasound enables the characterisation of focal liver lesions, regardless of the presence or absence of underlying chronic liver disease. Contrast enhanced ultrasound is also useful in staging and follow-up of cancer patients and in monitoring local ablative treatment. Contrast enhanced ultrasound is expected to be considerably increased and replace many computed tomography and magnetic resonance imaging examinations in near future, according to the European Federation of Societies for Ultrasound in Medicine and Biology guidelines. Therefore, it is necessary to take measures in order to meet the demand for an increasing number of these procedures.  相似文献   
69.
医用透明质酸钠预防腹部手术后腹腔粘连的临床观察   总被引:9,自引:0,他引:9  
目的 观察医用透明质酸钠对预防腹部手术后腹腔粘连的作用。方法 136 0例腹部手术患者 ,关腹前于腹膜及腹腔创面涂抹医用透明质酸钠 (sodiumhyaluronate)凝胶剂 3~ 15ml,随访期间 ,2 3例患者获 2次手术探察的机会 ,观察腹腔粘连程度 ,并与同期未用透明质酸钠凝胶剂的 2 6例 2次手术患者作对比分析。结果观察组 :腹腔粘连Ⅰ级 11例 ,Ⅱ级 9例 ,Ⅲ级 3例 ,Ⅳ级 0例 ;对照组 :Ⅰ级 1例 ,Ⅱ级 5例 ,Ⅲ级 17例 ,Ⅳ级 3例。两组轻度粘连分别为 87%和 2 3% ;两组重度粘连分别为 13%和 77%。两组患者手术后腹腔内粘连情况比较 ,差异有显著意义 (P <0 0 1)。结论透明质酸钠凝胶对腹部手术后预防腹腔粘连具有明显效果。  相似文献   
70.
凝固酶阴性葡萄球菌检测在慢性前列腺炎中的意义   总被引:21,自引:0,他引:21  
目的 研究慢性前列腺炎与凝固酶阴性葡萄球菌 (CNS)的关系 ,探讨前列腺液中CNS检测的临床意义。 方法 对 4 2 8例慢性前列腺炎患者采用Meares Stamey四段取样法作前列腺液细菌培养和药敏试验。患者年龄 18~ 4 6岁 ,平均 31岁。病程 3~ 32个月 ,平均 6个月。慢性前列腺炎症状指数 (NIH CPSI)平均 2 3.2分。 结果  4 2 8例均行细菌培养 ,其中 2 4 8例 (5 7.94 % )分离出细菌。革兰阳性菌 195例 (78.6 3% ) ,其中葡萄球菌 16 0例 (6 4 .5 2 % ,16 0 / 2 4 8) ,CNS 89例 (35 .89% ,89/ 2 4 8) ;CNS中以表皮葡萄球菌为主者 81例 (32 .6 6 % ) ,其次为腐生葡萄球菌 3例和溶血性葡萄球菌 2例 ;NIH CPSI积分与细菌培养结果无明显相关。CNS对常用抗菌药物 (β 内酰胺类、喹诺酮类、氨基糖苷类 )耐药率较高 (5 1.9%~ 10 0 % )。 结论 CNS为慢性前列腺炎的主要致病菌 ,应引起高度重视 ;适时监测前列腺液病原菌及药敏试验对临床诊断和治疗慢性前列腺炎具有重要意义。  相似文献   
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