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排序方式: 共有272条查询结果,搜索用时 31 毫秒
21.
KAZUYOSHI SUENARI M.D. YU‐FENG HU M.D. HSUAN‐MING TSAO M.D. CHING‐TAI TAI M.D. CHERN‐EN CHIANG M.D. YENN‐JIANG LIN M.D. SHIH‐LIN CHANG M.D. LI‐WEI LO M.D. TUAN TA‐CHUAN M.D. PI‐CHANG LEE M.D. NGUYEN HUU TUNG M.D. SHIH‐YU HUANG M.D. TSU‐JUEY WU M.D. SHIH‐ANN CHEN M.D. 《Journal of cardiovascular electrophysiology》2010,21(10):1114-1119
Gender Differences in Patients With AVNRT. Introduction: The detailed electrophysiological characteristics of the gender differences associated with atrioventricular nodal reentrant tachycardia (AVNRT) have not been clarified. This study investigated the gender‐related electrophysiological differences in a large series of patients undergoing radiofrequency catheter ablation. Methods and Results: A total of 2,088 consecutive AVNRT patients (men/women 869/1,219) who underwent catheter ablation were enrolled in this study. We evaluated the gender differences in their electrophysiological characteristics. Women had a significantly younger age of onset, higher incidence of multiple jumps, shorter AH interval, atrial effective refractory period (ERP), anterograde fast pathway ERP, anterograde slow pathway ERP, and retrograde slow pathway ERP, and longer ventricular ERP than men. The incidence of baseline ventriculoatrial dissociation was lower in women than in men. Women needed less isoproterenol/atropine to induce AVNRT. No gender differences in the radiation exposure time, procedure time, complication rate, acute success rate, or second procedure rate were noted. Both typical and atypical AVNRT were more predominant in women. In the patients with atypical AVNRT, there was no significant gender difference in incidence of baseline ventriculoatrial dissociation; however, the retrograde slow pathway ERP was significantly shorter in women than in men. Women of premenopausal age (≤50 years old) had a significantly higher incidence of anterograde multiple jumps and a retrograde jump phenomenon, and a shorter anterograde slow pathway ERP and retrograde slow pathway ERP than those of women over 50 years old. Conclusion: Gender differences in the anterograde and retrograde AV nodal electrophysiology were noted in the patients with AVNRT. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1114‐1119) 相似文献
22.
目的:应用脂多糖(Lipopolysaccharide,LPS)刺激人单核细胞白血病细胞系THP-1细胞,模拟体外脓毒症模型,了解单核细胞系统在产生内毒素耐受时,糖皮质激素受体-α(Glucocorticoid receptor-α,GR-α)在转录水平上的表达。方法:用无血清培养基培养人THP-1细胞,将细胞随机分为4组(A、B、C、D),分别用不同浓度LPS刺激THP-1细胞24 h后,再改变LPS浓度刺激上述各组细胞24 h,分别提取RNA和蛋白质,以逆转录聚合酶链反应(RT-PCR)检测GR-α的mRNA表达,用西部印迹法(Western Blotting)检测NF-κB蛋白质表达,以酶联免疫吸附试验(ELISA)检测培养液中肿瘤坏死因子-α(TNF-α),白细胞介素1β(IL-1β),白细胞介素10(IL-10)水平。结果:A、B、C、D组GR-αmRNA与-βactin比值,NF-κB蛋白与GAPDH比值差异有统计学意义(P<0.01),在受到LPS刺激时,GR-αmRNA与NF-κB蛋白的表达负相关(r=0.816,P<0.01)。结论:内毒素耐受的THP-1细胞GR-α表达上调,这可能在THP-1细胞的内毒素耐受时炎症反应的发生起到重要作用。 相似文献
23.
Suspitsin EN Sokolenko AP Togo AV Lazareva YR Turkevich EA Matsko DE Henrich KO Borresen-Dale AL Schwab M Cornelisse CJ Imyanitov EN 《International journal of cancer. Journal international du cancer》2007,120(2):297-302
Amplification of HER2, C-MYC and CCND1 oncogenes is a hallmark of breast cancer (BC); however, its involvement in the bilateral form of this disease has not been investigated yet. In this study, 50 bilateral BC (biBC) pairs (100 tumors) and 72 control unilateral BC were examined using real-time PCR analysis of microdissected archival tissues. In biBC, the frequency of >3-fold oncogene amplification was 6/100 (6%) for HER2, 6/100 (6%) for C-MYC and 7/100 (7%) for CCND1. Altogether, 18/100 (18%) biBC tumors had increased gene dosage of at least one oncogene. Tumors forming synchronous biBC pairs had amplification in 11/46 cases (24%). In 3 of 8 patients with amplification-positive carcinomas, the amplification was detected in both neoplasms: 2 biBC had concordant activation of the same oncogene (HER2 and CCND1, respectively), and in the remaining case distinct oncogenes were affected (HER2 and C-MYC). In contrast, amplifications in metachronous biBC were strongly discordant: none of 27 first carcinomas carried this abnormality, while the frequency of amplification in second tumors (7/27; 26%) was similar to the one observed in unilateral BC (20/72; 28%). The trend toward concordance of oncogene amplification status in synchronous but not in metachronous biBC pairs can be explained by the nearly identical natural history of the disease in simultaneously arising tumors. The skewed pattern of amplifications in metachronous biBC might be attributed to their association with adverse BC prognosis; it appears that only patients with amplification-negative first BC have sufficient chances to survive until the development of the contralateral carcinoma. 相似文献
24.
25.
M. L. X. FU A. ILEBEKK X. XU G. PERGOLA P. ERIKSSON K. A. KIRKEB
EN G. AKSNES J. HOEBEKE . HJALMARSON 《Acta physiologica (Oxford, England)》1994,151(3):291-299
The Gi-mediated muscarinic receptor-adenylyl cyclase system was examined in stunned myocardium induced by either three or five brief ischaemic periods after β-adrenoceptor blockade by timolol (0.1 mg kg-1). The mid-left anterior descending coronary artery was occluded for 2, 10 and 2 min in four pigs, and for 2, 2, 5, 10 and 2 min in four other pigs. All the ischaemic periods were separated by 30 min of reperfusion and the biopsies were obtained 60 min after the last ischaemic period. Segment length function was measured in the ischaemic region and in the control region supplied by the left circumflex artery. In the two groups, the percentage systolic shortening was reduced equally, to 59±9 and 58±10% of control in the region subjected to ischaemia and only minimally in the control region. The biopsies from the stunned region from both groups showed: (1) no change in either the affinity for carbachol or the number of binding sites of the muscarinic receptors; (2) no alterations in messenger RNA encoding for the α subunit-2 of the inhibitory guanine nucleotide binding protein, as demonstrated by northern blot and solution hybridization; (3) no change in membrane-bound inhibitory guanine nucleotide binding protein, as shown by enzyme immunoassay utilizing a specific anti-peptide antibody, and (4) unchanged inhibition of stimulated adenylyl cyclase activity. These results suggest that there is an intact inhibitory guanine nucleotide binding protein-mediated muscarinic receptor adenylyl cyclase system in the stunned porcine myocardium. 相似文献
26.
测定了Gemini表面活性剂在pH值为10.86,NaBr浓度为1.0mol/L的溶液气/液界面上的表面压一分子面积的等温线。用自制的Brewster角显微镜(BAM)观察了由Gemini表面活性剂在界面上所形成单分子膜的微区形貌随表面压的变化。结果表明:当pH值为10.86时,Gemini表面活性剂在1.0mol/L NaBr溶液的气/液界面上生成了凝聚态的单分子膜;当表面压较低时,观察到在界面上形成了同心圆结构;随着表面压的增加,这些同心圆可发生聚并而形成多中心结构。 相似文献
27.
Papillary adenoma of the prostatic urethra: Report of two cases 总被引:1,自引:0,他引:1
MUSTAFA ÖZGÜR TAN YAKUP KORDAN NUR DENZ ÖZLEM ERDEM LKER EN BRAHM BOZKIRLI 《International journal of urology》2003,10(8):459-462
Papillary adenoma of the prostatic urethra is a rare cause of hematuria, hemospermia and lower urinary tract obstruction, especially in young adults. We report two cases of papillary adenoma and their endoscopic views. One of the patients had a lesion located on the verumontanum and presented with hematuria, hemospermia and symptoms of lower urinary tract obstruction. The other patient had papillary lesions located in the paramontanal gutter and presented with persistent painless hematuria. The origin of both lesions was proven to be prostatic epithelial differentiation using immunohistochemical identification of prostate-specific antigen. Papillary adenoma is believed to be benign, therefore, both lesions were carefully excised and fulgurated transurethrally. 相似文献
28.
目的 探讨双探头SPECT心肌灌注显像时位移伪影的影像特征和识别方法。方法 将心脏模型置于检查床上,与受检患者的心脏方向一致。在图像采集过程中,模型依次沿相当于患者左右、头尾和前后方向分别在不同起始点、对不同帧数作一定距离的位移。结果位移伪影的共同特点是表现为室壁放射性分布不均匀,“热区”与“冷区”交替出现,在短轴上最早出现,且表现最为明显;伪影进一步发展会在水平长轴和垂直长轴上表现为心尖附近放射性稀疏或缺损,出现与相邻室壁伴行且形态相近的“伴影”。结论位移伪影主要表现为室壁放射性分布不均,“热区”与“冷区”交替出现,在短轴图像上易于早期发现。 相似文献
29.
In this investigation, we studied the importance of cellular glutathione (GSH) in the hexose monophosphate shunt (HMPS) activity of unstimulated human erythrocytes and the mechanism by which pyruvate stimulates the HMPS. The rate of HMPS activity was measured by the production of radioactive CO2 from 14C-1-glucose or 14C-1-ribose using a vibrating reed electrometer and ionization chamber. HMPS activity was not significantly impaired by N-ethylmaleimide (NEM) in concentrations which bound all red cell GSH. Red cells incubated under carbon monoxide (CO), an experimental condition which eliminates peroxide production, still had HMPS activity which was 44% of the value under air. Pyruvate stimulation of the HMPS was unaffected by doses of NEM which bound all cellular GSH or by incubation under CO. These data indicated that pyruvate stimulation of the HMPS occurs by pathways which do not involve peroxide formation, GSH, or oxygen. This study indicates that sulfhydryl blockade of GSH does not necessarily inhibit HMPS activity and that HMPS activity in red cells may respond to reactions not linked directly to glutathione reduction. 相似文献
30.
目的探讨老年冠心病合并糖尿病患者经皮冠状动脉介入(PCI)置入雷帕霉素洗脱支架(SES)治疗的远期疗效。 方法回顾性随机入选2003年1月至2007年12月住院期间老年冠心病合并糖尿病患者行PCI 100例,并入选同时期100例无糖尿病的冠心病患者行PCI为对照组。随访5年,随访包括心绞痛复发、死亡、心肌梗死、卒中和再次血运重建的主要不良心脑血管事件。结果 两组支架术成功率均为100%。随访率100%,随访5年,糖尿病组与非糖尿病组术后并发症发生率(8.0%、7.0%)、卒中发生率(5%、3.0%)、心源性死亡率(0%、0%)差异无显著性(均为ρ〉0.05)。再次血运重建率(30.0%、14.0%)、非致死性心肌梗塞(6.0%、2.0%)心绞痛复发率(42%、20%)、全因死亡率(10%、2.0%)糖尿病组高于非糖尿病组;但心源性病死率均为0%。结论:老年患者选择性冠脉内置入药物洗脱支架安全,成功率高,远期疗效尚好,但糖尿病仍是远期不良预后的独立预测因素。 相似文献