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51.
BACKGROUND: Premature atherosclerosis is a clinical feature in untreated acromegaly. Increased postprandial lipoprotein remnant levels are associated with premature atherosclerosis. In most studies, remnants have been measured indirectly using retinyl esters (RE) as a chylomicron core label. Remnants can also be directly quantified by immunoseparation using monoclonal antibodies to apolipoprotein (apo) AI and apo B100 to remove nonremnant lipoproteins. Cholesterol is quantified in the remaining apo E-rich remnant fraction (RLP-C). OBJECTIVE: The aim of the present study was to investigate the role of postprandial lipaemia in patients with acromegaly to further define abnormalities leading to increased susceptibility for atherosclerosis. PATIENTS: In a case-control study, the plasma postprandial lipoprotein remnant fraction (RLP-C and RE) were analysed in six patients with active acromegaly [two females, four males; aged 53 +/- 9 years; body mass index (BMI), 29 +/- 4 kg/m2] and in six normolipidaemic control subjects (matched for age, gender, BMI and apo E genotype). They underwent an oral vitamin A fat loading test. RESULTS: Baseline plasma triglycerides (TG) were not significantly different in patients (1.75 +/- 0.71 mM) and controls (1.15 +/- 0.46 mM). Lipoprotein lipase activity was significantly lower in patients than in controls (108 +/- 21 vs. 141 +/- 19 U/l, respectively; P < 0.05). Baseline plasma apo E levels were higher in patients (60.8 +/- 7.9 mg/l) than in controls (48.3 +/- 5.9 mg/l; P < 0.05). No differences were found in the area under the postprandial TG curve (AUC-TG), the incremental AUC-TG (DeltaAUC-TG) and AUC-RE in the Sf < 1000 remnant fraction. However, fasting plasma RLP-C concentrations, isolated by immunoseparation, were increased in patients with active acromegaly (0.41 +/- 0.13 mM) compared to control subjects (0.20 +/- 0.07 mM; P < 0.05). Incremental postprandial RLP-C response (corrected for fasting values) was also significantly elevated in patients (2.14 +/- 1.19 mM/h/l) compared to controls (0.86 +/- 0.34 mM/h/l; P < 0.05). In both groups, the maximal RLP-C concentration was reached between 2 and 4 h. CONCLUSIONS: In conclusion, the atherogenic postprandial remnants, represented by RLP-C, were significantly elevated at baseline and in the postprandial period, whereas the larger-sized remnants, represented by retinyl esters (Sf < 1000), were not different from controls. The disturbances in the postprandial RLP-C response increased the susceptibility for premature atherosclerosis as observed in patients with acromegaly.  相似文献   
52.
53.
7-(4,7-二取代香豆素-3-乙酰氨基)头孢菌素的合成   总被引:2,自引:0,他引:2  
范华娟  段廷汉  李明华   《药学学报》1989,24(3):175-181
本文根据构效关系,设计并合成了17个7-(4,7-二取代香豆素-3-乙酰氨基)头孢菌素衍生物。其缩合方法采用酰氯法、Vilsmeier试剂法及混合酐法。初步体外抑菌试验表明,化合物对革兰氏阳性菌和少数革兰氏阴性菌有较强的抗菌作用。进一步药理试验尚在进行。  相似文献   
54.
Thirty symptomatic indirect carotid cavernous fistulas were treated between 1978 and 1986 with a variety of treatment modalities. Combined carotid artery and jugular vein compression resulted in a complete cure in seven of 23 patients (30%) and improvement in one additional patient. There were no complications from this treatment, which is performed by the patient on an outpatient basis. Patients in whom carotid jugular compression therapy failed or who demonstrated cortical venous drainage or visual decline were treated with intravascular embolization. Embolization resulted in complete cure in 17 of 22 (77%) and improvement in four of 22 (18%). One patient required surgical excision of the involved dura after embolization to achieve complete cure. There was one permanent complication (stroke), which resulted in mild weakness caused by clot formation on a catheter.  相似文献   
55.
本文报道了以1,7-双取代-1,4-二氢-4-酮-1,8-萘啶-3-羧酸,用混合酸酐法与7-ACA,7-ADCA,7-ACT和7-ACD缩合,合成了24个1,7-双取代-1,4-二氢-4-酮-1,8-萘啶-3-甲酰胺头孢菌素衍生物,通过葡聚糖凝胶(Sephadex LH-20)及离心薄层层析纯化精制,得到纯品。体外抑菌试验结果表明:大多数新头孢菌素衍生物对革兰氏阳性菌具有较好的抗菌作用。尚有一些新头孢菌素衍生物对某些革兰氏阴性菌具有中等敏感程度。  相似文献   
56.
A newborn with pulmonary atresia with intact ventricular septum (PA-IVS) was treated with radiofrequency current perforation of the atretic pulmonary valve. As the right ventricle was hypoplastic (z-value of the tricuspid valve: —4) the arterial duct was stented with a Gianturco-Roubin GR II stent. Early postinterventionally, the patient became cyunotic and compromised blood flow across the stented ductus arteriosus despite adequate stent position was detected echographically. The newborn was treated successfully with the implantation of a Palmaz stent (Johnson & Johnson Interventional Systems, Warren, NJ, USA) into the obstructed Gianturco-Roubin GR II stent. The Gianturco-Roubin GR II stents might be associated with the risk of early stent stenosis after implantation in actively contracting tissues like the ductus arteriosus. In patients with early stent stenosis after ductal stenting, bailout implantation of a subsequent stent can be performed. Transcatheter procedures can be effective means for therapy of PA-IVS . (J Interven Cardiol 2000;13:39–44)  相似文献   
57.
人尿中几种雄激素及蛋白同化激素的HPLC测定   总被引:3,自引:0,他引:3  
毕红钢  周同惠 《药学学报》1989,24(3):207-211
对HPLC分离及定量测定人尿中雄激素及蛋白同化激素的方法进行了初步研究。确定了六种甾体激素的分离条件及内标定量方法。固定相为C8键合硅胶,甲醇—乙腈—水(4:5:6)恒溶剂洗脱,程序流速。紫外检测器波长254 nm。检测限可至1 ng以下。本法采用Sep-Pak C18小柱进行尿样净化,回收率高而且稳定。操作简便快速。对尿样中甾体葡萄糖醛酸甙结合物的酶促水解条件也进行了初步探索。  相似文献   
58.
刘春胜  张霁  周同惠 《药学学报》1991,26(9):682-687
本文叙述了用GC-MS联用技术研究脱氢氯甲睾酮人体内代谢的方法。尿样中的甾体化合物经大孔树脂吸附提取后,酶解。浓缩并衍生化,进行GC-MS分析。在服药后8~30h的尿样中,检出了脱氢氯甲睾酮原型,并发现了七个代谢产物。分析色谱和质谱数据,得到了这些代谢物的结构及其浓度变化趋势,推测了脱氢氯甲睾酮可能的体内代谢模式,确定了筛检尿中脱氢氯甲睾酮的特定代谢物和特征检测离子,比较了不同的样品处理方法对分析结果的影响。  相似文献   
59.
Reiman  TH; Balfe  DM; Weyman  PJ 《Radiology》1987,163(1):49-56
In a 5-year period, 92 patients with biliary obstruction proximal to the pancreatic segment were evaluated with computed tomography (CT). Seventy-three were judged to have technically optimal studies. Observations of the level of obstruction were compared with data from 50 percutaneous transhepatic cholangiograms; CT data enabled the level of obstruction to be correctly predicted in 46. CT enabled correct prediction of the distribution of obstructing lesions in all 18 patients with intrahepatic obstruction. Forty-four of the 73 patients had pathologic examination of the porta hepatitis. CT findings of obstructing mass and lesser omental nodes resulted in correct prediction of malignancy in 25 (92%) of 27 patients; the absence of such findings enabled correct prediction of benign disease in 13 (77%) of 17 individuals. CT is most valuable as a noninvasive means of planning surgical or radiologic drainage procedures in patients with biliary obstruction.  相似文献   
60.
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