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101.
The differentiation of pulmonary vein (PV) electrograms from atrial far-field signals during PV isolation (PVI) for atrial fibrillation (AF) may be difficult. In addition, owing to highly variable PV ostial sizes, current fixed-diameter circular PV mapping catheters may not yield optimal electrograms. We evaluated an expandable, circular 15–25 mm diameter, 20-pole mapping catheter for PV mapping during sustained AF in 25 patients. After selective PV angiography to define the ostial position and size, the catheter was introduced into each PV and withdrawn to the most stable proximal position, with optimal wall contact ensured by progressive loop expansion. At each PV ostium, electrograms recorded at high resolution (HR) were compared with those recorded at a resolution similar to that of a standard 10-pole Lasso catheter. After PVI performed during ongoing AF, the presence of residual far-field potentials (FFP) under both set-ups was compared. We mapped 97 PV, including 4 pairs with common ostia. In the HR recordings, the PV potentials had greater amplitude (0.5 ± 0.1 vs 0.3 ± 0.1 mV, P = 0.001) and fragmentation, whereas left atrial FFP were minimized. After successful isolation of all PV, FFP were observed in 33% of left superior and 28% of left inferior PV on the HR recordings, compared to 66% and 61%, respectively under normal resolution. Catheter stability and optimal wall contact, in combination with HR electrograms can optimize circumferential PV mapping during AF and improve the discrimination of FFP postablation.  相似文献   
102.
Summary In 1981 generalized anaphylaxis was registered on 166 occasions in Dutch general and academic hospitals. Clinical details of 120 of those patients revealed that in 107 anaphylaxis was either probable (n=90) or possible (n=17), whereas in 13 cases some other reaction than anaphylaxis had occurred. The series of confirmed cases contained 46 men and 61 women, with mean ages of 47 y and 48 y, respectively.There was a complete recovery in 102 patients and two patients died. Hypotension was present in 79 cases (74%), dyspnoea in 34 cases (32%) and a skin reaction, mainly urticaria, erythema or angioedema, was mentioned in 62 cases (58%). Most cases of anaphylaxis were drug-induced (76%), the main causes being the analgesic glafenine and contrast media. Glafenine was mentioned as the cause in 36% of all admissions for drug-induced anaphylaxis. Only 3.7% of cases had been reported to the voluntary reporting scheme of the Netherlands Centre for Monitoring of Adverse Reactions to Drugs.On the basis of reimbursement data, the risk of developing severe anaphylaxis to glafenine was estimated at 11.7–19.3-fold relative to indomethacin, and 13.4–20.2-fold relative to oral penicillins.  相似文献   
103.
A method, based on bedside determinations of blood glucose by nursing staff, was designed to control the administration of insulin to diabetic patients during and following open heart surgery. A computer-controlled intravenous infusion pump was used to deliver the insulin. Excellent control of the hyperglycaemia normally associated with open heart surgery was achieved, with 84 percent of measured blood glucose values falling within 2 mmol/litre of the target value of 6 mmol/litre. The method proved to be simple, effective, and safe.  相似文献   
104.
Remote telemetry may facilitate the management of implantable devices. We tested the reliability of a new automatic, wireless home monitoring (HM) system that archives data every 24 hours. We retrospectively analyzed archival data from 276 consecutive pacing system implants to define temporal atrial fibrillation (AF) patterns and associated ventricular rate. An "AF day" was defined by a >20%/24 hour mode switch (MS) duration, irrespective of the MS number. Management decisions resulting from transmissions were noted. A pilot study confirmed that 89% of 22,356 transmissions were successful, of which >90% were received in <5 minutes. Data integrity was 100% preserved. Overall, AF developed in 29 patients (10.5%), representing a total of 645 AF days (mean = 22.2 ± 29.6 AF, median = 9 days), over 12 ± 2 months of monitoring. AF was infrequent (50% of 24 hours. Ventricular rates during 645 AF days in 29 patients averaged 95.1 ± 9.9 beats/min (median = 94 beats/min). Ventricular rates were >80 beats/min in 25 ± 30 AF days (median = 11 days). HM enabled rapid anticoagulation decisions. In recipients of implantable devices, automatic wireless telemetry with HM was efficient and reliable. Its application may overcome some current challenges in AF management by early notification and precise measurement of both AF burden and ventricular rate during AF.  相似文献   
105.
乳剂依托咪酯对心脏手术病人麻醉诱导期循环功能的影响   总被引:1,自引:0,他引:1  
目的 本文应用乳剂依托咪酯,观察其对心脏手术病人麻醉诱导期的循环影响。方法 选择心脏手术病人80例,心功能Ⅲ~Ⅳ级,随机分为两组,每组2 0例:Ⅰ组(水剂组) :水剂依托咪酯0 2 5mg kg-1;Ⅱ组(乳剂组) :乳剂依托咪酯0 2 5mg kg-1。记录麻醉前、注射依托咪酯前、后,气管插管后1min和3min时段的各监测参数。观察不自主肌肉颤动,注射疼痛感及过敏反应等不良反应。结果 显示两种剂型的依托咪酯各时间点的SBP、DBP、MAP、HR各组间无显著差异(P >0 0 5 )。两组在注射依托咪酯后SBP、DBP、MAP、HR轻度下降,但与注射前均无统计学差异(P >0 0 5 )。不自主肌肉运动Ⅰ组8例、Ⅱ组6例:两组间无显著差异(P >0 0 5 )。静脉注射处疼痛Ⅰ组14例、Ⅱ组1例,两组间显著差异(P >0 0 5 )。结论 乳剂依托咪酯具有麻醉诱导平稳,心血管影响轻微,副作用少在应用上优于水剂依托咪酯,可用于高龄及心脏功能受损害患者的麻醉诱导。  相似文献   
106.
目的探讨内源性热休克蛋白90(HSP90)在缺氧心肌细胞丝氨酸苏氨酸蛋白激酶(AKT)相关信号通路中的作用。方法建立新生Wistar大鼠心肌细胞缺氧模型,将细胞分为正常组、缺氧组、加入HSP90特异性阻断剂格尔德霉素后再缺氧组(格尔德霉素+缺氧组)。于缺氧后1、3、6、12、24、48h用噻唑蓝法检测心肌细胞的活力;缺氧24h,原位缺口末端标记法检测心肌细胞凋亡指数(AI);缺氧1、3、6、12、24h,蛋白质印迹法检测大鼠心肌细胞中内源性HSP90及AKT表达水平。结果(1)缺氧24、48h,缺氧组、格尔德霉素+缺氧组细胞活力均较正常组明显下降(P〈0.05);格尔德霉素+缺氧组细胞活力缺氧12h即开始明显下降,缺氧48h时明显低于缺氧组(P〈0.05)。(2)缺氧24h,缺氧组细胞AI为(10.7±1.2)%,明显高于正常组[(1.9±0.3)%.P〈0.05];格尔德霉素+缺氧组细胞AI为(26、3±5.3)%,明显高于缺氧组(P〈0.01)。(3)缺氧12h,缺氧组心肌细胞内源性HSP90及AKT表达水平高于正常组与格尔德霉素+缺氧组;缺氧24h,缺氧组有所下降.格尔德霉素+缺氧组则下降更明显。结论内源性HSP90对维持心肌细胞的活力有重要作用.缺氧心肌细胞AKT表达水平可受内源性HSP90表达水平的影响。  相似文献   
107.
紫外线对晶状体上皮细胞损伤的研究进展   总被引:5,自引:0,他引:5  
唐建  刘谊 《眼视光学杂志》2003,5(3):187-189
紫外线,特别是紫外线B,是老年性白内障的环境致病因素,晶状体上皮细胞生理状态的改变是白内障发生的早期表现。本综述总结了近年来国内外关于紫外线损伤对晶状体上皮细胞影响的研究,以及紫外线对晶状体上皮细胞的生物损伤效用和损伤机制。  相似文献   
108.
 目的探讨环孢素A(cyclosporine A,CsA)是否逆转野百合碱(monocrotaline,MCT)诱导的右心室重构及其作用机制的初步探讨。方法雄性SD大鼠随机分正常对照组,MCT模型组,CsA低、高剂量组(0.33和1mg·kg-1)。MCT造模后14~21d给CsA(ig,bid)。造模22d右心导管术检测右室收缩压(RVSP);称右室自由壁(RV)及左心室加室间隔(LV+SEP)重,计算右心肥大指数(RVHI=RV/LV+SEP);光镜及电镜观察右室结构变化;免疫组化检查右室心肌细胞PCNA的表达。结果CsA逆转MCT所引起RVSP、RVHI的升高(P<0.05或P<0.01)、右室心肌细胞肥大、线粒体肿胀变性及PCNA抗原的过表达。高剂量CsA作用更明显。结论CsA(1mg·kg-1 ig,bid)能明显逆转MCT诱导的右室重构,其机制可能与降低右室后负荷及抑制右室心肌细胞肥大有关。  相似文献   
109.
Flavocoxid (Limbrel), a proprietary mixture of flavonoid molecules (baicalin and catechin), was tested against a traditional nonsteroidal anti-inflammatory drug, naproxen, for the management of the signs and symptoms of moderate osteoarthritis (OA) in humans. Discomfort and global disease activity were used as the primary end points, and safety assessments were also taken for both treatments as a secondary endpoint. In this double-blind study, 103 subjects were randomly assigned to receive either flavocoxid [500 mg twice daily (BID)] or naproxen (500 mg BID) in a 1-month onset of action trial. Outcome measures included the short Western Ontario and McMaster University Osteoarthritis Index, subject Visual Analogue Scale for discomfort and global response, and investigator Visual Analogue Scale for global response and fecal occult blood. Both flavocoxid and naproxen showed significant reduction in the signs and symptoms of knee OA (P ≤ .001). There were no statistically detectable differences between the flavocoxid and naproxen groups with respect to any of the outcome variables. Similarly, there were no statistically detectable differences between the groups with respect to any adverse event, although there was a trend toward a higher incidence of edema and nonspecific musculoskeletal discomfort in the naproxen group. In this short-term pilot study, flavocoxid was as effective as naproxen in controlling the signs and symptoms of OA of the knee and would present a safe and effective option for those individuals on traditional nonsteroidal anti-inflammatory drugs or cyclooxygenase-2 inhibitors. A low incidence of adverse events was reported for both groups.  相似文献   
110.
Nocturnal Sleep‐Related Eating Disorder (NSRED) is a well‐documented sleeping disorder where the person is reported to experience bizarre eating behavior during sleep. Although various causes are implicated in this disorder, role of drugs cannot be ruled out. Here we narrate an interesting rare case report of a drug‐induced new onset NSRED, where a 45‐year‐old man on zolipdem performed an unexpected and bizarre eating behavior during somnambulistic state, type of which has not been reported earlier in the literature. The case falls under even rarer category as such behavior in sleep is reported mainly in woman. © 2008 by Wiley Periodicals, Inc. Int J Eat Disord 2009  相似文献   
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