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31.
Mário Martins Oliveira Nogueira da Silva Ana Teresa Timóteo Joana Feliciano Lídia de Sousa Sofia Santos Fernando Marques Rui Ferreira 《Revista portuguesa de cardiologia》2007,26(7-8):691-702
Atrial electrical remodeling plays a part in recurrence of atrial fibrillation (AF). It has been related to an increase in heterogeneity of atrial refractoriness that facilitates the occurrence of multiple reentry wavelets and vulnerability to AF. AIM: To examine the relationship between dispersion of atrial refractoriness (Disp_A) and vulnerability to AF induction (A_Vuln) in patients with clinical paroxysmal AF (PAF). METHODS: Thirty-six patients (22 male; age 55+/-13 years) with > or =1 year of history of PAF (no underlying structural heart disease--n=20, systemic hypertension--n=14, mitral valve prolapse--n=1, surgically corrected pulmonary stenosis--n=1), underwent electrophysiological study (EPS) while off medication. The atrial effective refractory period (AERP) was assessed at five different sites--high (HRA) and low (LRA) lateral right atrium, high interatrial septum (IAS), proximal (pCS) and distal (dCS) coronary sinus--during a cycle length of 600 ms. AERP was taken as the longest S1-S2 interval that failed to initiate a propagation response. Disp_A was calculated as the difference between the longest and shortest AERP. A_Vuln was defined as the ability to induce AF with 1-2 extrastimuli or with incremental atrial pacing (600-300 ms) from the HRA or dCS. The EPS included analysis of focal electrical activity based on the presence of supraventricular ectopic beats (spontaneous or with provocative maneuvers). The patients were divided into group A--AF inducible (n=25) and group B--AF not inducible (n=11). Disp_A was analyzed to determine any association with A_Vuln. Disp_A and A_Vuln were also examined in those patients with documented repetitive focal activity. Logistic regression was used to determine any association of the following variables with A_Vuln: age, systemic hypertension, left ventricular hypertrophy, left atrial size, left ventricular function, duration of PAF, documented atrial flutter/tachycardia and Disp_A. RESULTS: There were no significant differences between the groups with regard to clinical characteristics and echocardiographic data. AF was inducible in 71% of the patients and noninducible in 29%. Group A had greater Disp_A compared to group B (105+/-78 ms vs. 49+/-20 ms; p=0.01). Disp_A was >40 ms in 50% of the patients without A_Vuln and in 91% of those with A_Vuln (p=0.05). Focal activity was demonstrated in 14 cases (39%), 57% of them with A_Vuln. Disp_A was 56+/-23 ms in this group and 92+/-78 ms in the others (p=0.07). Using logistic regression, the only predictor of A_Vuln was Disp_A (p=0.05). CONCLUSION: In patients with paroxysmal AF, Disp_A is a major determinant of A_Vuln. Nevertheless, the degree of nonuniformity of AERP appears to be less important as an electrophysiological substrate for AF due to focal activation. 相似文献
32.
目的:研究成釉细胞瘤(AB)和牙源性角化囊肿(OKC)中c-mycmRNA的表达,探讨c-myc在AB和OKC中的发生、发展及其生物学意义。方法:使用原位杂交法检测54例AB、16例OKC和7例口腔正常黏膜(NOM)组织中c-mycmRNA的表达,并将AB按原发、复发、恶变分组,结果使用χ2检验进行统计分析。结果:AB、OKC及NOM组织中c-mycmRNA的阳性表达率分别为81.5%(44/54)、75.0%(12/16)和14.3%(1/7),3组比较有显著性差异(χ2=15.488,P<0.05)。原发组AB中c-mycmRNA的阳性表达率为71.0%,复发组为94.7%,恶变组为100.0%,伴随原发、复发、恶变,差异有显著性(χ2=16.912,P﹤0.05)。结论:c-myc表达在AB的发生、发展中有重要作用;c-mycmRNA的表达与AB的临床生物学行为有关,伴随其生物学行为变化,c-mycmRNA表达增强;提示c-myc有可能成为评价预后的有效指标。 相似文献
33.
眼轴线后部眶容积增大与眼球内陷比值的测定研究 总被引:1,自引:0,他引:1
目的:通过测量眼眶爆裂性骨折伴有眼眶扩大患者的后部眼眶容积、观察眼球内陷出现的时间及程度,研究后部眶容积扩大与眼球内陷的关系比值,为病情预测和眶内填充手术提供比较精确的参考数据。方法:将96例患者按发病时间分为早期病例组(60例、受伤时间1周以内)和晚期病例组(36例、受伤时间3个月以上),早期组除进行后部眼眶容积测量外,分别于1周、2周、3周测定眼球突出度(相差>1mm为阳性),记录眼球内陷出现时间,用卡方检验进行统计学分析;晚期组测量后部眶容积增大值和眼球内陷量,对其相关性采用Pearson统计方法进行统计学分析,并得出回归方程及相关系数。结果:早期组60例患者中,(58.33%)例患者在1周内出现眼球内陷,4(880%)例在2周内出现内陷,3周时有5(388.33%)例呈现出内陷;2周时出现眼球内陷的例数与1周时有显著性差异(χ2=62.484,P<0.001),2周时出现眼球内陷例数与3周时无差异(χ2=1.563,P>0.05),1周时出现眼球内陷例数与3周时有显著差异(χ2=76.885,P<0.001),后部眶容积增大与眼球内陷的比值约为1.0,两者之间呈正相关(r=0.994,P<0.001),即后部眶容积每增加1ml,产生1.0mm的眼球内陷。结论:眼球内陷通常于伤后2周~3周出现,3个月时趋向稳定;后部眶容积增大与眼球内陷产生比值为1.0,呈正相关;后部眶容积扩大与眼球内陷比值可预测发生眼球内陷的可能性和程度,为手术矫正眼球内陷提供可靠、精确的参考,具有十分重要的临床指导意义。 相似文献
34.
骨外科患者拔尿管时注入药物对排尿的影响 总被引:4,自引:0,他引:4
目的探讨提高长时间留置导尿管病人拔管后2h内排尿成功率的方法。方法按入院先后随机将64例导尿的男性骨折病人分两组,单数为观察组,双数为对照组。对照组常规拔尿管,观察组拔尿管时遵医嘱注入地塞米松5mg+2%利多卡因5ml+生理盐水5ml+庆大霉素8万U,比较首次排尿的自觉症状,包括尿痛、排尿困难、排尿障碍等。结果观察组较对照组病人首次排尿出现自觉症状的例数明显减少(P<0.01),有显著性差异。结论拔尿管时注入药物安全有效,明显提高了长期置管病人拔除尿管后首次排尿的成功率,减轻了病人的痛苦,有广泛的应用价值。 相似文献
35.
人工肱骨头置换术治疗高龄患者肱骨近端复杂骨折 总被引:3,自引:1,他引:2
目的 探讨伴有全身性疾病的高龄肱骨近端复杂骨折患者人工肱骨头置换术围手术期处理、术中操作与术后康复的特殊性及手术的可能性。方法 2002年10月~2005年2月对8例68岁以上肱骨近端四部分复杂骨折患者行人工肱骨头置换术。患者均伴有内科疾病,合并两种以上疾病者3例,对所有伴发疾病进行手术前、后内科系统处理,并有针对性地注意术中操作与术后康复指导。结果术后原有合并症均得到控制。所有患者获3~30个月随访。参照美国加州洛杉矶关节成形改良评分系统(SSMH)综合评分:优1例,良5例,中1例,差1例。8例患者疼痛方面得分平均为9.5分,功能方面得分为8.0分,肌力和运动方面得分为7.5分。结论 对有伴发疾病的高龄肱骨近端复杂四部分骨折患者行人工肱骨头置换术虽存在较大风险,但只要认真处理伴发疾病,有针对性地注意术中操作与术后康复指导,可以平稳渡过手术期,并可提高此类患者的生活质量。 相似文献
36.
Jorge Polónia Jo?o Maldonado Rui Ramos Susana Bertoquini Mary Duro Cristina Almeida Jo?o Ferreira Loide Barbosa José Alberto Silva Luís Martins 《Revista portuguesa de cardiologia》2006,25(9):801-817
BACKGROUND: Portugal has one of the highest mortality rates from stroke, a high prevalence of hypertension and probably a high salt intake level. AIM: To evaluate Portuguese salt intake levels and their relationship to blood pressure and arterial stiffness in a sample of four different adult populations living in northern Portugal. METHODS: A cross-sectional study evaluating 24-hour urinary excretion of sodium (24 h UNa+), potassium and creatinine, blood pressure (BP), and pulse wave velocity (PWV) as an index of aortic stiffness in adult populations of sustained hypertensives (HT), relatives of patients with previous stroke (Fam), university students (US) and factory workers (FW), in the context of their usual dietary habits. RESULTS: We evaluated a total of 426 subjects, mean age 50 +/- 22 years, 56% female, BMI 27.9+/-5.1, BP 159/92 mmHg, PWV 10.4+/-2.2 m/s, who showed mean 24h UNa+ of 202 +/- 64 mmol/d, corresponding to a daily salt intake of 12.3 g (ranging from 5.2 to 24.8). The four groups were: HT: n = 245, 49 +/- 18 years, 92% of those selected, 69% treated, BP 163/94 mmHg, PWV 11.9 m/s, 24 h UNa+ 212 mmol/d, i.e. 12.4 g/d of salt); Fam: n = 38, 64 +/- 20 years, 57 % of those selected, BP 144/88 mmHg, PWV 10.5 m/s, 24 h UNa+ 194 mmol/d, i.e. 11.1 g/d of salt; US: n = 82, 22 +/- 3 years, 57% of those selected, BP 124/77 mmHg, PWV 8.7 m/s, 24h UNa+ 199 mmol/d, i.e. 11.3 g/d of salt; FW: n = 61, 39 9 years, 47% of those selected, BP 129/79 mmHg, PWV 9.5 m/s, 24 h UNa+ 221 mmol/d, i.e. 12.9 g/d of salt. The ratio of urinary sodium/potassium excretion (1.9 (0.4) was significantly higher in HT than the other three groups. In the 426 subjects, 24h UNa+ correlated significantly (p < 0.01) with systolic BP (r = 0.209) and with PWV (r=0.256) after adjustment for age and BP. Multivariate analysis showed that BP, age and 24h UNa+ correlated independently with PWV taken as a dependent variable. CONCLUSIONS: Four different Portuguese populations showed similarly high mean daily salt intake levels, almost double those recommended by the WHO. Overall, high urinary sodium excretion correlated consistently with high BP levels and appeared to be an independent determining factor of arterial stiffness. These findings suggest that Portugal in general has a high salt intake diet, and urgent measures are required to restrict salt consumption in order to prevent and treat hypertensive disease and to reduce overall cardiovascular risk and events. 相似文献
37.
Rui Providência 《Revista portuguesa de cardiologia》2006,25(11):1043-1058
This article discusses the cardiovascular protection afforded by low to moderate consumption of ethanol and the role of ethanol-induced preconditioning. Ethanol, a compound that is found in many popular beverages, has a whole range of cardiovascular protective effects when consumed in low to moderate doses. Although they have yet to be totally clarified, recent data suggest that a combination of several actions at the biochemical and molecular levels play a role in this protection. These include favorable changes in lipid metabolism, antioxidant effects, changes in hemostasis and platelet aggregation, arterial vasodilation mediated by NO release, induction of the expression of cardioprotective proteins, insulin sensitization and lower levels of inflammatory markers. Special emphasis will be given to ethanol-induced preconditioning. Some of the compounds present in red and white wine, such as resveratrol and quercetin, are also partly responsible for some of the cardioprotective effects of alcoholic drinks. These are due to antioxidant effects and changes in platelet aggregation, endothelial function and inflammatory response. The last part of the paper will focus on the clinical applications and possibilities raised by these new findings. 相似文献
38.
利多卡因治疗支气管哮喘的临床应用 总被引:6,自引:0,他引:6
利多卡因(Lidocaine)为合成局部麻醉药,由于有较强的穿透力、作用时间长、安全范围大,可适用于各种方法的局部麻醉,是临床上应用最广泛的局麻药之一。利多卡因还有抗心律失常作用,用于治疗心律失常,临床应用证明利多卡因是治疗各种快速型室性心律失常具安全、高效,速效的首选药,甚至一度作为评价各种新抗心律失常药疗效的标准药物。利多卡因还适用于其它药物治疗无效的癫痫持续状态的控制。早些年有报道,气道吸入利多卡因可抑制剧烈运动引起的气道痉挛,1991年起用于治疗支气管哮喘,治疗哮喘常采用雾化吸入,或合用岛激动药等其它抗哮喘药物。这里介绍利多卡因在支气管哮喘(下简称哮喘)方面的临床应用。 相似文献
39.
手部皮肤套脱伤的治疗 总被引:5,自引:2,他引:3
目的探讨手部皮肤套脱伤的治疗方法。方法2002年4月-2004年11月,治疗22例手部皮肤套脱伤患者,其中19例分别通过吻合血管、套脱皮肤修薄回植及多切口引流等方法进行修复。另有3例,因无法行套脱皮肤回植而采用腹部带蒂皮瓣修复。结果术后随访3个月-1年。19例套脱皮肤原位回植患者中,13例皮肤完全成活,4例有部分皮缘坏死,经中药换药后愈合,2例行切痂植皮术后治愈。手功能按ATN功能评分评定:优9例,良7例,中3例,优良率为84%,患者对手外形及功能满意。3例腹部皮瓣修复者,皮瓣全部成活。术后随访5个月-1年,手外形及功能明显差于皮肤原位回植者。结论尽可能地回植手部套脱皮肤,对手功能及外形的恢复具有重要意义。 相似文献
40.
Objective To evaluate the clinical effect of placing double J stent using a ureteroscope in early managing ureterovaginal fistula.Methods Twenty-eight patients cases with ureterovaginal fistula from 2002 to 2008 were treated early with placing double J stent using a ureteroscope and the clinical data were reviewed.Results Twenty-two of 28 cases were treated and double J stent was placed in them by a uretero-scope and 75% (21/28)of cases were cured.Four of 21 cases were treated twice by a ureteroscope and were cured finally.7 cases with failure ureterovaginal treatment underwent ureterocystostomy and were cured.The follow-up from 6 months to 33 months (average 10.1±6.4 months)showed that all of the 28 cases had been cured and had no urinary fistula.Conclusion Placing double J stent using a ureteroscope is the first choice of operative procedure for the early treatment of ureterovaginal fistula. 相似文献