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991.
Objective: Mechanical heart valves can cause thromboembolic complications, possibly due to abnormal flow patterns that produce turbulence downstream of the valve. The objective of this study was to investigate whether three different bileaflet valve designs would exhibit clinically relevant differences in downstream turbulent stresses. Methods: Three bileaflet mechanical heart valves (Medtronic Advantage®, CarboMedics© Orbis™ Universal and St. Jude Medical® Standard) were implanted into 19 female 90 kg pigs. Blood velocity was measured during open chest conditions in the cross sectional area downstream of the valves with 10 MHz ultrasonic probes connected to a modified Alfred® Pulsed Doppler equipment. As a measure of turbulence, Reynolds normal stress (RNS) was calculated at three different cardiac output ranges (3–4, 4.5–5.5, 6–7 L/min). Results: Data from 12 animals were obtained. RNS correlated with increasing cardiac outputs. The highest instantaneous RNS observed in these experiments was 47 N/m2, and the mean RNS taken spatially over the cross sectional area of the aorta during systole was between 3 N/m2 and 15 N/m2. In none of the cardiac output ranges RNS values exceeded the lower critical limit for erythrocyte or thrombocyte damage for any of the valve designs. Conclusions: Reynolds normal stress values were below 100 N/m2 for all three valve designs and the difference in design was not reflected in generation of turbulence. Hence, it is unlikely that any of the valve designs causes flow induced damage to platelets or erythrocytes.  相似文献   
992.
This study examined the contribution of the quality of life (QoL) domains physical, social and psychological functioning to the explanation of overall QoL. Various disorders may differentially affect QoL domains due to disease-specific factors and, consequently, the relationship between QoL domains and overall QoL may vary between diseases. We therefore studied this relationship for several diseases as well as the differential impact of these diseases on QoL. The present study had a cross-sectional design. We selected patients (aged 57 years and older) with one of the following eight chronic medical conditions: lung disorder, heart condition, hypertension, diabetes mellitus, back problems, rheumatoid arthritis, migraine, or dermatological disorders. The total group of respondents included 1457 patients and 1851 healthy subjects. Regression analyses showed that the domain of psychological functioning contributed to overall QoL for all disorders, whereas physical and social functioning contributed to overall QoL for some disorders. Differences were found between most patient groups and healthy subjects with respect to physical functioning; with respect to social and psychological functioning some groups differed from the healthy group. Explanations for the findings and implications for clinical practice are discussed.  相似文献   
993.
Parkinson's disease (PD) is a major cause of disability. To date, there have been no large-scale efforts to measure the quality of PD care because of a lack of quality indicators for conducting an explicit review of PD care processes. We present a set of quality indicators for PD care. Based on a structured review of the medical literature, 79 potential indicators were drafted. Through a two-round modified Delphi process, an expert panel of seven movement disorders specialists rated each indicator on criteria of validity, feasibility, impact on outcomes, room for improvement, and overall utility. Seventy-one quality indicators met validity and feasibility thresholds. Applying thresholds for impact on outcomes, room for improvement, and overall utility, a subset of 29 indicators was identified, spanning dopaminergic therapy, assessment of functional status, assessment and treatment of depression, coordination of care, and medication use. Multivariable analysis showed that overall utility ratings were driven by validity and impact on outcomes (P < 0.01). An expert panel can reach consensus on a set of highly rated quality indicators for PD care, which can be used to assess quality of PD care and guide the design of quality improvement projects.  相似文献   
994.
目的探讨脑脊液14-3-3蛋白定量检测对散发性Creutzfeldt-Jakob病(sCJD)的诊断价值。方法采用Capture Assay方法定量检测14例sCJD患者(sCJD组)、10例痴呆患者(OD组)、12例非痴呆患者(ND组)脑脊液14-3-3蛋白的含量。结果脑脊液中14-3-3蛋白含量中位数(MD)sCJD组为40.00ng/mg,OD组为2.65ng/mg,ND组为3.10ng/mg;sCJD组脑脊液中14-3-3蛋白含量明显高于OD组及ND组(均P<0.01)。以脑脊液14-3-3蛋白含量≥9ng/ml为分界值时,其对sCJD诊断的敏感性为86.7%,特异性为86.4%,阳性预测值为81.3%,阴性预测值为90.5%。结论应用Capture Assay方法定量检测脑脊液中14-3-3蛋白含量对于临床可疑sCJD的患者有较高的敏感性和特异性。  相似文献   
995.
OBJECTIVES: To present a series of women with recurrent molar pregnancies, including rare familial cases, and discuss etiology and treatment options. METHODS: We performed a detailed clinical evaluation and pedigree analysis of five Egyptian women with recurrent pregnancy loss due to molar pregnancy. RESULTS: The women had a history of four to nine consecutive hydatidiform moles but of no viable pregnancies. Two of the women had molar pregnancies with different husbands who themselves had viable offspring from previous wives; and three of them, who belonged to a family with extensive intermarriage, had a pedigree consistent with an autosomal recessive maternal-effect mutation. CONCLUSIONS: Recurrent pregnancy loss due to habitual molar pregnancy is uncommon and familial cases are extremely rare. The etiology of this disorder is not well understood but likely results from a maternal-effect mutation. Management options are limited, especially for couples who desire to have their own genetic offspring.  相似文献   
996.
目的 探讨N -乙酰半胱氨酸 (NAC)治疗不同病期慢性阻塞性肺疾病 (COPD)的疗效。方法  49例稳定期、急性发作期COPD患者 ,随机分为观察组 (2 5例 )和对照组 (2 4例 ) ,观察组除给予常规治疗外 ,加用NAC(每次 2 0 0mg ,3/d ,连用 2个月 ) ;对照组仅给予常规治疗。治疗前后观察所有患者外周血淋巴细胞DNA损伤程度。结果 治疗前后比较 ,观察组稳定期、急性发作期DNA损伤明显降低 ,差异有显著性 (P <0 .0 5)。对照组稳定期DNA损伤程度亦有一定程度的改善 ,但差异无显著性 (P >0 .0 5) ,急性发作期DNA损伤程度降低 ,差异有显著性 (P <0 .0 5)。结论 COPD患者体内存在氧化 -抗氧化失衡 ,抗氧化治疗可降低COPD患者外周血淋巴细胞DNA损伤程度 ,急性发作期出现氧化应激。  相似文献   
997.
大鼠延髓腹外侧区在可乐定心血管效应中的作用   总被引:1,自引:1,他引:0  
目的:探讨大鼠延髓腹外侧区(VLM)在介导可乐定心血管效应中的作用。方法:氨基甲酸乙酯麻醉SD大鼠,应用微量注射和细胞外记录等方法观察尾端延髓腹外侧区(CVLM)和头端延髓腹外侧区(RVLM)内局部给予可乐定导致的心血管活动变化。结果:单侧CVLM微量注射可乐定(5nmol/100nl,n=10)不仅能明显升主动脉血压(AP)和增加心率(HR)(P<0.01),而且能增加同侧RVLM压力敏感性神经元(n=80)的放电频率(P<0.01),而单侧RVLM微量注射可乐定(5nmol/100nl,n=9),明显降低AP和HR(P<0.01)。结论:RVLM和CVLM在介导可乐定的心血管效应中具有不同的作用。  相似文献   
998.
目的总结冠心病患者行冠状动脉旁路移植术(CABG)和激光心肌血运重建术(TMLR)中的治疗难点、围术期处理要点,以提高冠心病患者的外科治疗效果。方法1997年5月~2006年1月,1405例冠心病患者中在体外循环下行CABG825例,其中单纯CABG666例,CABG+心瓣膜手术98例,CABG+室壁瘤手术55例,CABG+左心房粘液瘤摘除术2例,CABG+室间隔穿孔修补术2例,CABG+升主动脉成形术1例,CABG+纵隔内肿瘤切除术1例;非体外循环下CABG(OPCAB)500例;单纯TMLR30例,CABG+TMLR50例。结果每例移植旁路血管2.9±1.0支。住院死亡42例(3.0%),死亡原因包括出血、心肌梗死、低心排血量综合征、肾功能衰竭、多器官功能衰竭等。术后发生并发症70例,包括出血、低心排血量综合征、心肌梗死、肾功能不全等,均经积极的对症处理后治愈或好转。术前心绞痛(CCS)为~级的1177例患者中,术后1154例(98.0%)改善为0~级。术后随访857例(62.9%),随访时间8.3±2.9个月。随访6个月时788例(91.9%)无心绞痛发作,复查超声心动图提示:左心室射血分数0.66±0.10,较术前提高7.9%,生活质量较术前大为提高。结论CABG已成为治疗冠心病最有效的常规手术,只要能正确掌握适应证,有效地加强围术期管理,便可以扩大手术适应证范围,降低手术死亡率和并发症发生率,提高手术疗效。  相似文献   
999.
Assessment of autonomic dysfunction in Parkinson's disease: the SCOPA-AUT.   总被引:2,自引:0,他引:2  
We developed a questionnaire to assess autonomic symptoms in patients with Parkinson's disease (PD) and evaluated its reliability and validity. Based on the results of a postal survey in 46 PD patients, 21 multiple system atrophy patients, and 8 movement disorders specialists, items were included according to their frequency, burden, and clinical relevance. The questionnaire was evaluated in 140 PD patients and 100 controls, and test-retest reliability was established in a sample of 55 PD patients. The SCOPA-AUT consists of 25 items assessing the following regions: gastrointestinal (7), urinary (6), cardiovascular (3), thermoregulatory (4), pupillomotor (1), and sexual (2 items for men and 2 items for women) dysfunction. Test-retest reliability was good. Autonomic problems increased significantly with increasing disease severity for all autonomic regions, except sexual dysfunction. We conclude that SCOPA-AUT is a reliable and valid questionnaire that evaluates autonomic dysfunction in PD.  相似文献   
1000.
Depression is common in Parkinson's disease (PD) and affects 30 to 50% of all patients. In contrast to the wealth of research on depression in PD, little is known about the occurrence of depression in other movement disorders. The primary objective of the current study was to determine whether the high prevalence of depression symptoms seen in PD is also found in other movement disorders, by directly comparing rates of specific depression symptoms and depression severity across PD, dystonia, and essential tremor (ET). Three hundred and fifty-four patients with PD, 83 patients with dystonia, and 53 patients with ET completed the Beck Depression Inventory (BDI). We found no significant between-groups differences for depression severity, frequency, or endorsement of specific depression symptoms. Forty-eight percent of PD patients, 37.3% of dystonia patients, and 34% of ET patients were found to be at least mildly depressed (BDI score of 10 or higher). The most commonly endorsed symptoms were fatigability, difficulty with work, anhedonia, and sleep disturbance. Clinicians should be aware that depression is a frequent problem in dystonia and ET, in addition to PD, and inquire about depression symptoms in these patients so that they can be appropriately treated.  相似文献   
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