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11.
Modified Pulmonary Vein Isolation in AF Ablation. Introduction: Pulmonary vein isolation (PVI) is the primary ablation therapy in patients with atrial fibrillation (AF). We hypothesized that high dominant frequency (DF) sites (AF nests during sinus rhythm [SR]) adjacent to the PV ostia are associated with the atrial substrate that maintains AF, and PVI incorporating the high‐frequency AF nests may have a higher efficacy. Methods and Results: In a prospective and randomized comparison, 126 symptomatic paroxysmal AF patients that underwent PVI were enrolled. We compared the efficacy of a modified PVI (ablation line: 1.0–1.5 cm from the PV ostium with encircling the AF nests [spectral analysis with DF >70 Hz during SR, Group II]) versus the anatomy‐guided conventional PVI (Group I). In Group II, the DF value along the PV ostium was lower than 70 Hz after the PVI. The primary endpoint was the freedom from symptomatic atrial arrhythmias after a single procedure. We also followed the autonomic function by a time‐domain analysis of the heart rate variability. In both groups, AF nests were observed and electric isolation was successfully obtained in all patients. With a mean duration of 16 ± 6.1 months of follow‐up, Group II had a higher single procedure efficacy without drugs (78.7% vs 66.1%, log‐rank test: P = 0.02), and fewer repeat procedures (6.6% vs 23%; P = 0.04), as compared to Group I. Conclusion: PVI incorporating the high frequency AF nests adjacent to the PV ostia had a better single procedure efficacy. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1155–1162, November 2012)  相似文献   
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ABSTRACT: BACKGROUND: Numerous emerging data from research on osteoporosis among Asians found differences from Caucasians. Therefore, the aim of this study was to determine the prevalence of vitamin D insufficiency and osteoporosis in elderly participants from two nursing homes in Thailand, a country located near the equator. METHODS: The subjects of this cross-sectional study comprised 93 elderly Thai women who were living in institutional long-term nursing homes for the aged. Demographic data, daily food and calcium intake, physical activity, and sunlight exposure were measured. Lumbar spine and femoral neck bone mineral density (BMD) and biochemical levels including serum 25 hydroxyvitamin D [25(OH)D] and bone turnover markers were assessed. Vitamin D insufficiency was defined as 25(OH)D level < 70 nmol/l. RESULTS: The mean age of subjects was 75.2 +/- 6.0 (SD) years. Dietary calcium intake was low (322 +/- 158 mg/day) The mean 25(OH)D level was 64.3 +/- 14.9 nmol/L and the prevalence of vitamin D insufficiency was 38.7 % (95 % CI: 28.8 %, 49.4 %). There was no correlation between serum 25(OH)D concentrations and age (r = -.11, p = 0.3). The mean BMD of lumbar spine and femoral neck were 0.92 +/- 0.19 and 0.65 +/- 0.10 g/cm2, respectively. Nearly a half of the subjects had osteopenia (44.1 %, 95 % CI: 33.8 %, 54.8 %) and osteoporosis (47.3 %, 95 % CI: 36.9 %, 57.9 %). Circulating C-terminal telopeptide of type I collagen (CTx) level correlated significantly with both lumbar spine (r = -0.26, p = 0.01) and femoral neck BMD (r = -0.25, p = 0.02). CONCLUSIONS: More than one-third of Thai elderly women residing in nursing homes had vitamin D insufficiency. Almost all nursing home residents had osteoporosis and/or osteopenia.  相似文献   
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目的 探讨丧亲者孤独感与家庭功能相关关系.方法 采用便利抽样,使用家庭关怀度问卷(APGAR)和UCLA孤独量表,对264名汶川地震丧亲者的孤独感和家庭功能进行问卷调查.结果丧亲者孤独感均分( 42.06±9.96)分,50%以上丧亲者体验到中等水平的孤独感;孤独感在性别方面差异无统计学意义(P>0.05),在年龄、经济状况、婚姻状态和家庭结构方面差异有统计学意义(P<0.01);丧亲者孤独感与家庭功能呈负相关(P<0.01).结论孤独感是丧亲者普遍存在的心理问题且处于中等水平;丧亲者的家庭功能从不同侧面对其孤独感产生影响,良好的家庭功能有助于减轻孤独感.  相似文献   
15.
目的:观察应用MIPO技术(微创钢板接骨术)锁定钢板内固定治疗胫骨粉碎性骨折的临床效果。方法:使用MIPO技术对20例胫骨干粉碎性骨折进行锁定钢板内固定。术后平均随访8个月。结果:20例骨折均复位良好、顺利愈合,功能恢复良好。结论:运用MIPO技术锁定钢板内固定治疗胫骨干粉碎性骨折具有较高的临床应用价值。  相似文献   
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Aim  This study aimed to identify and examine predictors of short-term absences of staff nurses working in hospital settings reported in the research literature.
Background  Front-line staff nurse absenteeism contributes to discontinuity of patient care, decreased staff morale and is costly to healthcare.
Evaluation  A systematic review of studies from 1986 to 2006, obtained through electronic searches of 10 online databases led to inclusion of 16 peer-reviewed research articles. Seventy potential predictors of absenteeism were examined and analysed using content analysis.
Key issue  Our findings showed that individual 'nurses' prior attendance records', 'work attitudes' (job satisfaction, organizational commitment and work/job involvement) and 'retention factors' reduced nurse absenteeism, whereas 'burnout' and 'job stress' increased absenteeism. Remaining factors examined in the literature did not significantly predict nurse absenteeism.
Conclusions  Reasons underlying absenteeism among staff nurses are still poorly understood. Lack of robust theory about nursing absenteeism may underlie the inconsistent results found in this review. Further theory development and research is required to explore the determinants of short-term absenteeism of nurses in acute care hospitals.
Implications for nursing management  Work environment factors that increase nurses' job satisfaction, and reduce burnout and job stress need to be considered in managing staff nurse absenteeism.  相似文献   
18.
目的建立霍乱弧菌的基于红外荧光标记引物的扩增片段长度多态性(AFLP)分型方法,评价脉冲场凝胶电泳(PFGE)和AFLP对霍乱弧菌的分型能力。方法选择PFGE带型均不相同的47株霍乱弧菌作为评价菌株,建立AFLP对于霍乱弧菌的分型方法;确定操作程序后选择83株分离自1962-2005年11个省的霍乱弧菌,进行AFLP和PFGE对于霍乱弧菌分型能力的比较。AFLP分型方法采用了红外荧光标记PCR引物,利用LI-COR4300自动测序仪完成电泳、SagaMX软件对电泳图谱进行编辑。PFGE采用PulseNet提供的标准化程序。结果AFLP用于霍乱弧菌分型时选择性引物携带碱基数为1,最优引物组合为EcoRⅠ-G/MseⅠ-T,AFLP分型实验的重复性达到99.2%。AFLP将83株霍乱弧菌分为52个型别,D值为0.9545;PFGE将此83株菌分为44种带型,D值为0.9251。结论优化固定了AFLP对于霍乱弧菌的分型程序,重复性好;AFLP比PFGE具有更好的分型能力,能够用于分离菌株的分子分型。结合已成为实验室网络监测标准分析方法的PFGE,可对分离株做更细致的分型比较。  相似文献   
19.
目的:体外模仿部分胃肠道消化酶解过程,考察大豆蛋白酶解消化能否产生血管紧张素转化酶抑制剂(ACEI)活性肽及其活性状况,以揭示大豆蛋白体内消化酶解与ACEI的活性关系。方法:模拟人体胃肠道消化过程,以胃蛋白酶结合胰蛋白酶,相继酶解大豆分离蛋白(SPI),经色谱分离,动态检测不同阶段ACEI肽片段及其活性大小。结果:胃蛋白酶酶解过程前20min内,酶解液ACEI活性达到最高点,随后在胰蛋白酶酶解阶段其抑制活性下降。180min后的酶解产物,其半抑制活性浓度IC50值为0.28±0.06 mg/ml。同时,未经酶解的SPI液在0.73mg/ml时无ACEI活性。SPI酶解液经各种色谱分离后的组分,其IC50值从0.13±0.03到0.93±0.08 mg/ml。低分子量和伴有疏水性基团的肽类最具ACE抑制活性。结论:体外模仿胃肠消化过程使用胃蛋白酶和胰蛋白酶酶解SPI可产生不同ACEI活性的肽片段,说明人体正常摄食消化大豆蛋白可产生血管紧张素转化酶抑制剂活性肽。  相似文献   
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We studied 3592 Swedish schoolchildren, 8 or 9 years old, examined for palpable submandibular, cervical and supraclavicular lymph nodes. All children were skin tested with 2 TU PPD RT23 and with 0.1 μ g of Mycobacterium avium sensitin or 0.1 μ g of M. scrofulaceum sensitin. A total of 991 children had palpable lymph nodes in any of the three locations. Among them, 811 had lymph nodes in one location, 162 in two locations and 18 in three. In 312 children, the lymph nodes were ± 5 mm in size in any location. The most common location was submandibular. Boys had a significantly higher prevalence of palpable lymph nodes than girls. There was also seasonal variation. Children infected by atypical mycobacteria (sensitin reaction ±6 mm) did not have a higher prevalence of palpable lymph nodes than those not infected.  相似文献   
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