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51.
Sixty six patients with dyspeptic symptoms underwent upper gastrointestinal endoscopy and biopsies for Helicobacter pylori culture. The number of H. pylori isolated increased with age reaching a peak at 51 to 60 years of age. Antral gastritis closely followed by duodenitis accounted for the highest number of H. pylori isolated, (87.5% and 85.7% respectively). In patients with duodenal ulceration only, 57% had H. pylori isolated from their antral biopsies, a result that was just slightly higher than that where no endoscopic diagnosis was made (50%). 相似文献
52.
The effects of beta 1- and beta 1 + beta 2-antagonists on the myocardial adaptation to exercise training were investigated in male Sprague-Dawley rats randomly divided into trained (treadmill, 1 hr/day, 5 days/week for 10 weeks at 27 m/min, 15% grade) without drug (TC), sedentary without drug (SC), trained treated with atenolol (TA) (10 mg/kg body wt, i.p.), trained treated with propranolol (TP, 30 mg/kg body wt, i.p.), and sedentary propranolol. Doses of both beta-antagonists were titrated to decrease the exercise heart rate by 25% compared to the controls. The heart weight and heart/body weight ratio were significantly greater in TC (1.28 +/- 0.07 g (P less than 0.01); 296 +/- 12 mg/100 g body wt (P less than 0.05) respectively) than in SC (1.09 +/- 0.04 g and 268 +/- 11 mg/100 g body wt), or in TP and TA. Myocardial mitochondrial protein was unchanged by training or beta-blockade. Citrate synthase and beta-hydroxyacyl CoA dehydrogenase activities were not altered. Carnitine palmitoyltransferase activity was increased in SP compared to SC. Training increased hexokinase activity only in TC (5.22 +/- 0.12 vs 4.26 +/- 0.23 mumol/min/g wet wt, P less than 0.01). Lactate dehydrogenase activity increased significantly (P less than 0.01) in both TC (383 +/- 14 mumol/min/g wet wt) and TA (372 +/- 14 mumol/min/g wet wt) compared to SC (276 +/- 14 mumol/min/g wet wt), but not in TP versus SP. These data indicate that (1) beta-adrenergic blockade prevents training-induced cardiac hypertrophy; (2) beta-antagonists have little effect on the myocardial oxidative capacity; and (3) while the training induction of myocardial hexokinase is inhibited by both beta 1- and beta 1 + beta 2-antagonists, myocardium may increase its ability to utilize lactate during exercise with training despite beta 1-blockade. 相似文献
53.
Enhancement of hepatic hemangiomas with levovist on coded harmonic angiographic ultrasonography. 总被引:5,自引:0,他引:5
Jung Hoon Kim Tae Kyoung Kim Bong Soo Kim Hyo Won Eun Pyo Nyun Kim Moon-Gyu Lee Hyun Kwon Ha 《Journal of ultrasound in medicine》2002,21(2):141-148
OBJECTIVE: To evaluate the pattern of contrast enhancement with Levovist on coded harmonic angiographic ultrasonography of hepatic hemangiomas. METHODS: Twenty hemangiomas were evaluated with coded harmonic angiographic ultrasonography and a microbubble contrast agent. Verification of the diagnosis of a hemangioma was made by means of dynamic computed tomography (n = 8), dynamic magnetic resonance imaging (n = 1), radionuclide scanning (n = 6), or follow-up ultrasonography (n = 5). Ultrasonographic images were obtained before contrast agent administration and with a bolus injection of 2.5 g of a microbubble contrast agent (300 mg/mL Levovist; Schering AG, Berlin, Germany) every 10 to 15 seconds for 5 minutes. The contrast enhancement patterns of the 20 hemangiomas were assessed. RESULTS: The tumor diameters as measured on ultrasonography were 7 to 97 mm (mean, 26.7 mm). Of the 20 hemangiomas, peripheral globular enhancement with progressive centripetal fill-in was shown in 15 (75%), rimlike enhancement with progressive centripetal fill-in was shown in 2 (10%), and homogeneous enhancement was shown in 1 (5%). In the remaining 2 lesions (10%), the enhancement patterns could not be seen, because they were not found on coded harmonic angiographic ultrasonography. CONCLUSIONS: Coded harmonic angiographic ultrasonography with a microbubble contrast agent can depict the typical enhancement pattern in most hepatic hemangiomas. 相似文献
54.
Poly(L-lysine)-g-poly(D,L-lactic-co-glycolic acid) micelles for low cytotoxic biodegradable gene delivery carriers. 总被引:3,自引:0,他引:3
Poly(lactic-co-glycolic acid) (PLGA)-grafted poly(L-lysine) (PLL) (PLL-g-PLGA) was synthesized to demonstrate its micelle-forming property in an aqueous solution. The micelles were used as a gene delivery carrier. The hydrodynamic diameter of PLL-g-PLGA micelles in an aqueous solution was ca. 149 nm with a narrow size distribution. Critical micelle concentration (cmc) was 9.6 mg/l. The PLL-g-PLGA micelles could be used to produce compact nanoparticulate complexes with plasmid DNA, which could efficiently protect the complexed DNA from enzymatic degradation by DNase I. The micelle/DNA complexes had highly compacted structure sized between 200-300 nm with a positive surface charge value. The PLL-g-PLGA micelles exhibited much higher transfection efficiency with lower cytotoxicity than PLL. Here, we demonstrated that biodegradable and cationic PLL-g-PLGA micelles could be used as an effective DNA condensation carrier for gene delivery system. 相似文献
55.
周济 《中华医学教育杂志》2002,(4):1-2
本次会议对经济全球化时代尤其是加入世界贸易组织之后,全面提升中国医学教育水平和质量,提高中国医学教育国际合作与竞争能力,具有十分重要的意义.要在国际竞争中立于不败之地,中国的高等医学教育必须增强紧迫感和危机感,加强国际交流与合作,加速高等医学教育国际化进程,积极研究并学习和借鉴医学教育国际标准,加快改革与发展,全面提高中国高等医学教育的综合实力.医学教育国际标准的引入,为我们重新审视和制定我国医学教育质量标准提供了十分有价值的参考. 相似文献
56.
QuantitativerelationshipbetweenpupillaryreflexfeatureanditsdiopterinretinoscopyXuShang(徐上);JiShangnian(计尚年)(DepartmentofOphth... 相似文献
57.
98例颅内肿瘤经手术和病理检查证实,其中36例脑瘤伴精神障碍,最常见的精神症状是情感淡漠,情感不稳,遗忘,意识模糊,嗜睡、痴呆。为最常见的部位为额顶部和颞叶部。 相似文献
58.
白细胞介素-13功能研究进展 总被引:5,自引:0,他引:5
白细胞介素-13主要由活化的Th2(CD4^ )细胞分泌,诱导单核巨噬细胞分化及延长寿命;促进MHC-Ⅱ,CD23表达;抑制炎性和趋化因子产生;诱导B细胞增殖,活化,刺激IgM,IgG的产生和重链的转换;使血管细胞粘附分子-1表达;抑制人类免疫缺陷病毒(HIV)复制;间接诱导巨噬细胞和NK细胞参与抗肿瘤作用。在变态反应性疾病和哮喘中引起呼吸道高反应性,嗜酸粒细胞性炎症,粘液分泌过多,基膜纤维化等,其受体是与IL-4Rα形成功能复合体而发挥作用。IL-13信号转导途径除了JAK/STAT6以外,尚有IRS-1,Fes,磷酸激酶,BCL-6/SOCS等途径。 相似文献
59.
冠状动脉造影正常的急性心肌梗死临床分析 总被引:2,自引:0,他引:2
目的对比观察急性心肌梗死(AMI)冠脉造影正常和异常患者的临床表现.方法同期144例AMI患者,于发病12h内行尿激酶溶栓,并于心梗后7~14d内行经皮冠状动脉造影术,梗死相关动脉(IRA)再通且无冠脉病变者为冠脉正常组,再通且有冠脉病变及PTC成功者为冠脉异常组.记录二组患者易患因素,观察ST段抬高总和及90min回落程度,比较二组住院期间心脏事件发生率,并于出院前行超声心动图检查.结果144例患者中冠脉正常组10例,冠脉异常组134例,前者较后者年龄轻,男性,吸烟等诱因多见;造影时TMI 3级多见;ST段抬高总和于90min回落明显(P<0.05);住院期间心脏事件发生率明显降低(P<0.05);出院前超声心动图提示左室射血分数较高(P<0.05).结论AMI冠脉造影正常者相对年龄轻,吸烟诱因多,住院期间心功能和临床预后好. 相似文献
60.
目的:研究田径运动员最大摄氧量和Wingate测试后血乳酸的变化,分析血乳酸对测试结果的意义。方法:测试田径短跑运动员36例和中长跑运动员29例的最大摄氧量和Wingate无氧功,以及测试后的血乳酸值。结果:最大摄氧量测试后血乳酸数值为9~11mmol/L左右,摄氧量与乳酸值没有直接相关关系,但不同项目之间有一定的差异;Wingate测试后血乳酸数值一般大于12mmol/L,测试的主要评价指标与乳酸值都有较高的相关关系。结论:血乳酸值对于最大摄氧量测试意义不大,但对于Wingate测试可以作为一项辅助评价指标。 相似文献