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101.
The inflammatory process and autoimmunity in the form of antibodies to oxidized LDL are important factors in the formation of the atherosclerotic plaque. We examined the time relationship of oxidized lipoprotein antibodies to the acute oxidative stress of myocardial infarction (MI). We also examined the relationship of C-reactive protein, an index of inflammation, and therefore of free radical production, to oxidized low-density lipoprotein (LDL) antibodies. We examined five groups of patients in a cross-sectional study: group 1, within 48 h of MI; group 2, two days to 1 week; group 3, 1-4 weeks; group 4, 1-3 months; and group 5, 3-6 months post MI. Nine patients with high antibody levels were re-examined 12 months after their first assessment. Malondialdehyde (MDA)-LDL and MDA-HDL antibodies were determined by an ELISA method. The highest MDA-LDL antibodies were found within 48 h of MI, but there was no significant difference in MDA- HDL antibodies between the groups. When 9/10 patients with LDL antibodies greater than the mean of 2.7 were re-examined 1 year later, there was a significant decrease in the mean antibody levels (5.2 +/- 1.7 vs. 3.2 +/- 0.6, p < 0.02). There was no correlation between antibodies to MDA-LDL and antibodies to MDA-HDL. There was a positive correlation between serum HDL cholesterol and antibodies to MDA-LDL (r = 0.4, p < 0.02) and a positive correlation between serum triglycerides and MDA-HDL antibodies (r = 0.39, p < 0.02). Acute MI appears to be associated with significantly higher C-reactive protein and antibodies to MDA-LDL, suggesting a possible acceleration of the atherosclerotic process immediately prior to MI.   相似文献   
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103.
This study was designed to investigate the effect of the convective cooling of the tip of the ablation electrode during temperature controlled radiofrequency ablation. In vivo two different application sites in the left ventricle of anaesthetised pigs were ablated and in vitro ablation was performed during two different flow-velocities in a tissue bath, while electrode contact pressure and position were unchanged. Target temperature was 80 °C. Obtained tip temperature, power consumption and lesion dimensions were measured. In vivo lesion volume, depth and width were found significantly larger for septal applications than apical applications (p<0.01) and more power was used (p<0.001). Obtained tip temperature was significantly lower in the septal applications (p<0.001). In vitro increased convective cooling by induction of flow yielded larger lesion volume, depth and width (p<0.01), and had higher power consumptions (p<0.01). Obtained tip temperature did not differ significantly. For the given chosen target temperature power consumption was positively related to lesion volume (r= 0.66 in vivo and 0.65 in vitro), whereas obtained tip temperature was not (r = - 0.49 in vivo and - 0.61 in vitro). We conclude that during temperature controlled radiofrequency ablation lesion size differs for septal and apical left ventricular applications. Differences in convective cooling might play an important role in this respect. This is supported by our in vitro experiments, where increased convective cooling by induction of a flow around the electrode tip increases lesion dimensions and power consumptions. Furthermore we conclude that for the given target temperature the power consumption is positively correlated with lesion volume (p<0.001), whereas the obtained tip temperature is not.  相似文献   
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105.
Diagnostic laparoscopy by physicians: we should do it   总被引:1,自引:0,他引:1  
Only a few centres in the UK practise diagnostic laparoscopy and liver biopsy; in comparison, laparoscopy is widely practised by physicians in Europe, the Far East and in the US. We consider the role of diagnostic laparoscopy in the assessment of liver disease in the 1990s, and describe the technique of laparoscopy, including how it may be performed safely in the endoscopy suite, under local anesthesia with mild sedation and analgesia, enabling direct visualization of the liver. We examine potential complications and contraindications. Complication rate and mortality are similar to that for percutaneous liver biopsy. Finally, the invaluable role of laparoscopy in diagnosing and staging chronic hepatitis, cirrhosis, liver tumours, hepatic infiltration, infection and structural abnormalities is considered.   相似文献   
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107.
目的:综述5'-一磷酸腺苷激活蛋白激酶对运动中骨骼肌糖代谢的作用及其机制。 资料来源:应用计算机检索Medline和Highwire1986-01/2006-10有关运动、5'-一磷酸腺苷激活蛋白激酶、骨骼肌糖代谢的文献,检索词“AMPK,glycometabolism,skeletal muscle,exercise”,限定文章语言种类为English。 资料选择:对资料进行初审,选取5'-一磷酸腺苷激活蛋白激酶与运动骨骼肌糖代谢有关的文献,排除重复研究。 资料提炼:共收集相关文献120篇,排除重复研究,纳入28篇。 资料综合:运动激活骨骼肌5'-一磷酸腺苷激活蛋白激酶(5'-AMP activated protein kinase,AMPK),AMPK激活后通过促葡萄糖转运和氧化、抑制糖原合成及促进糖原酵解而调节运动中的糖代谢。AMPK促葡萄糖转运的机制主要与促葡萄糖转运体4转位于胞膜有关,此过程涉及到AS160、一氧化氮、肌细胞增强因子2及过氧化物酶体增殖子γ辅激活因子1α等AMPK的下游靶:促糖原分解与抑制糖原合成的机制分别涉及到对糖原合成酶的抑制和磷酸果糖激酶的激活。 结论:AMPK在调控运动骨骼肌糖代谢中发挥着重要作用,阐明其机制有助于理解运动骨骼肌能量代谢的原理。  相似文献   
108.
Sorafenib is a small molecular inhibitor of several tyrosine protein kinases, including vascular endothelial growth factor receptor, platelet‐derived growth factor receptor and rapidly accelerated fibrosarcoma kinases, targeting signal transduction and angiogenic pathways. It is approved for the treatment of advanced renal cell carcinoma and hepatocellular carcinoma. The objectives of this prospective phase II trial were to assess the activity and tolerability of sorafenib in patients with recurrent or refractory myeloma. In total, 11 patients were enrolled. Patients received 2 × 200 mg of sorafenib orally twice daily until completing 13 full cycles or disease progression. Of the side effects, 8.8% grade 3 and 1.1% grade 4 occurred. Sorafenib treatment was effective in two patients who achieved a partial response and a continuous stable disease with duration of 24.4 months and 6.9 month, respectively. Further clinical investigations are recommended to investigate sorafenib single agent activity in myeloma subgroups with ras‐/BRAF‐/vascular endothelial growth factor receptor pathway activation and combination therapy approaches. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
109.
Schramm TK  Gislason GH  Vaag A 《药品评价》2011,8(13):10-10,13
研究纳入丹麦1997~2006年间107806例起始胰岛素促泌剂或二甲双胍单药治疗的2型糖尿病患者(年龄>20岁,没有使用过胰岛素单药和联合治疗)其中9607例患者既往存在心肌梗死史.随访时间3.3年,每3个月为一个区间,收集不同胰岛素促泌剂或二甲双胍的处方,如果某区间无处方量则以之前最多3个处方量的区间作为参考.  相似文献   
110.
褚国华  周启霆 《药学学报》1994,29(2):149-152
Reductive amination of8- benzyl-nortropinone(3 )with ammonium acetate andsodium cyanoborohydride yielded the 3 α-amino nortropane derivative 4 which was condensed withsubstituted benzoic acids using 2-bromo-N-methyl-pyridinium iodide as condensing reagent to give thetarget compounds 2a~ein an overall yield of 50~60%.Compound 2e showed marked and selectiveaffinity for D-2 receptor.Compound 2d showed definite affinity for D- 1 receptor besides markedaffinity for D-2 receptor.  相似文献   
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