Enhanced dispersion of atrial refractoriness as an electrophysiological substrate for vulnerability to atrial fibrillation in patients with paroxysmal atrial fibrillation.

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.     

应用微创内固定系统治疗胫骨近端骨折

目的总结应用微创内固定系统(LISS)治疗胫骨近端骨折的临床经验,讨论应用指征及手术技巧。方法分析2003年11月～2004年6月间应用LISS治疗的22例高能量胫骨近端骨折,其中男16例,女6例,平均年龄41.8岁(22～69岁)。按AO分型:41-A型7例,41-C型15例。其中9例合并其它骨折,5例为开放性骨折(GustiloⅢA3例,ⅢB2例)。结果平均随访15个月(12～17个月)。22例完全愈合;2例发生浅表感染,经保守治疗痊愈;患者完全负重时间15.2周(12～18周);X线愈合时间14.5周11～17周)。1例术后6个月随访出现关节面复位丢失,无固定失效及力线不正;关节活动度平(均为2°(0°～15°～98.6°(60°～120°;按照Johner-Wruhs胫骨骨折临床疗效评价法,术后6个月功能优))13例,良7例,中2例,差0例,优良率为90.9%。结论LISS治疗胫骨近端骨折,特别是干骺端粉碎的骨折具有较好的力学稳定性,骨折愈合率高,软组织损伤小,并发症发生率低,是一种有效的治疗手段。但作为新型的固定系统其有特殊的手术技巧及指征,临床应用时应充分理解。     

慢性硬膜下血肿术后并发症原因分析及应对措施

目的探讨慢性硬膜下血肿（chronic subdural hematoma，CSDH）术后并发症的原因及应对措施。方法回顾2000年至2004年手术治疗的85例CSDH患者，并结合有关文献进行相关分析。结果术后血肿复发3例，张力性气颅1例，脑挫裂1例，硬膜外血肿3例，脑脊液漏1例，脑内血肿1例。结论认识CSDH术后并发症的原因，早期采取有效措施，可有效预防并发症。     

阿立哌唑与氯氮平治疗精神分裂症对照研究

目的:探讨阿立哌唑与氯氮平对首发精神分裂症患者的临床疗效及安全性。方法:对64例精神分裂症患者随机分为两组,分别给予阿立哌唑与氯氮平治疗,疗程8周。用阳性与阴性症状量表(PANSS)和副反应量表(TESS)评定疗效和不良反应。结果:两组疗效差异无显著性(P>0.05),阿立哌唑不良反应显著少于氯氮平(P<0.01)。结论:阿立哌唑是一种安全有效的抗精神病药。     

Estimation of salt intake by urinary sodium excretion in a Portuguese adult population and its relationship to arterial stiffness.

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.     

Cardiovascular protection from alcoholic drinks: scientific basis of the French Paradox.

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.     

98例尿道下裂手术的体会

目的通过对尿道下裂手术的改进,进一步完善尿道下裂手术的技巧和护理。方法A组50例尿道下裂Ⅰ期成形术中,采用皮下连续内翻缝合形成新尿道,且固定于阴茎海绵体,由阴茎根部自下而上多层次,多点缝合皮瓣皮下组织至阴茎海绵体上,均无间隙和死腔。B组48例采用常规手术方式作对照。结果A组50例尿道下裂Ⅰ期成形术成功44例,B组48例成功17例,A组与B组相比成功率显著提高(P＜0．05)。结论尿道下裂Ⅰ期成形术成功率关键在于术者对术式掌握的熟练程度和术中及术后对每个细节的认真处理。     

微创固定系统治疗膝关节周围复杂骨折

目的应用微创固定系统(less invasive stabilizing system,LISS)治疗膝关节周围复杂骨折,探讨其手术适应证及疗效。方法2003年12月至2004年6月应用LISS技术治疗膝关节周围复杂骨折41例,男29例,女12例;年龄24￣67岁,平均40.6岁。胫骨近端骨折28例,股骨远端骨折13例。多发伤22例(53.7%),陈旧性骨折6例(14.6%),翻修手术1例。新鲜骨折均采用关节面切开复位、干骺端闭合复位及经皮钢板固定技术;陈旧性骨折及翻修手术采用有限切开及经皮钢板固定技术。结果单侧LISS手术时间平均87.2min。全部病例随访13～21个月,平均16个月。3例股骨远端骨缺损患者平均于术后21.3周(19～24周)行植骨术,植骨术后22.3周(18～24周)骨折愈合。其余患者愈合时间平均15.1周(11～23周),完全负重时间平均16.8周(12～25周)。术中发生螺钉脱落1例,提拉复位装置断裂1例,工具断裂1例,螺钉未能按计划置入2例。术后发生关节面复位丢失1例,无感染、内固定松动、断裂及失败病例。按照Rasmussen骨折复位评分标准,优31例、良10例。术后1年关节活动范围2.4°～95.6°。术后1年HSS评分平均88.4分(58～98分),其中优27例、良10例、中3例、差1例,优良率90.2%。结论LISS为膝关节周围复杂骨折提供了一种新的治疗方法,特别是对常规方法难以处理的骨折。但其手术理念及手术技术与传统手术不同,还需要一定病例与随访的积累才能确定其疗效。     

维生素D衍生物联合供者骨髓细胞输注诱导异基因大鼠心脏移植免疫耐受

目的 探讨同种异基因心脏移植后免疫耐受的诱导。方法 建立大鼠颈部异位心脏移植模型，按分组分别给予门静脉输注供者骨髓细胞(DBMC)(B组)、骨化三醇灌胃(C组)、输注DBMC及骨化三醇灌胃(D组)以及环孢素A(CsA)灌胃(E组)。观察移植心脏的存活时间及心肌组织病理改变，测定心肌组织中肿瘤坏死因子及细胞间粘附分子-1 mRNA的表达以及血清钙、磷浓度，进行受者与供者及无关第三品系大鼠脾细胞混合淋巴细胞培养(MLR)。结果 D组移植心脏的存活时间较其它各组显著延长(P＜0．05)；术后7d，C组、D组、E组受者脾细胞均能显著抑制供者及第三方无关供者脾细胞作为刺激细胞引起的MLR；D组手术前后血磷、血钙浓度的差异无显著性(P＞0．05)；各组急性排斥反应的程度，D组最轻；D组肿瘤坏死因子及细胞间粘附分子-1 mRNA的表达受到显著抑制，与对照组(A组)、B、C组比较，差异有显著性(P＜0．05)。结论 骨化三醇灌胃联合DBMC输注可显著延长移植心脏的存活时间，二者具有协同作用。