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51.
ABSTRACT. In order to detect deep vein thrombosis (DVT), 101 patients with acute medical or infectious disorders were examined with the 125I-fibrinogen uptake test. All patients were bedridden on admission and were scanned daily from the second to the eighth day. Thirteen patients developed a positive fibrinogen uptake test. Thus, if a positive test is interpreted as DVT, the incidence of DVT was 13% in our bedridden patients. Of the patients admitted because of heart disease or pneumonia 20% had DVT, but only 4% of those admitted with other diagnoses. Other clinical “risk factors” studied, could not identify patients who developed DVT.  相似文献   
52.
To evaluate the adaptation of the heart to exercise during pacing, 15 patients with permanent endocardial pacemakers were studied; nine patients had atrioventricular universal (DDD) pacemakers (Symbios 7005) and six patients had activity detecting rate-responsive ventricular (VVIR) pacemakers (Activitrax 8403). Left ventricular function in each patient during rate variable pacing was compared to ventricular function during VVI single-rate pacing. End-systolic and end-diastolic volume changes during exercise were measured by radionuclide angiography and the amount of volume change was used to assess left ventricular function. Both short-term (within 4 hours) and long-term measurements (after at least 4 weeks) were made at rest and at 50% of the maximal exercise capacity in DDD or VVIR mode and were compared with VVI single-rate pacing. All patients, when changed from DDD or VVIR mode to VVI single-rate pacing showed a significant increase of the end-diastolic volume during exercise, which increased even more after long-term VVI pacing. During long-term rate variable pacing, there was no increase of the end-diastolic volume during exercise. DDD or VVIR pacing initially showed a substantial increase of the end-systolic volume during exercise combined with a decrease of left ventricular ejection fraction, suggesting a decrease of the left ventricular contractility. After 4 weeks, contractility improved both with DDD and VVIR pacing. We conclude that short-term DDD and VVIR pacing induces a temporary impairment of left ventricular function that improves after 4 weeks, whereas long-term VVI pacing is associated with left ventricular dilatation even at moderate levels of exercise.  相似文献   
53.
Noise Reversion of a Dual Chamber Pacemaker without Noise   总被引:1,自引:0,他引:1  
Three patients are reported whose DDD pacemakers reverted to the asynchronous mode in the absence of skeletal muscle or electromagnetic (EMI) interference. In all three cases, the basic cardiac rhythm was atrial fibrillation with fast ventricular response due to intrinsic AV conduction. Noise reversion was triggered by the patients' own ventricular activity at cycle lengths shorter than the ventricular refractory period of the pulse generator. In one patient, asynchronous AV sequential pacing during atrial fibrillation was noted shortly after resuscitation from ventricular fibrillation; however, the initiation of the malignant ventricular arrhythmia by the pacemaker remains unproven. The mechanism of noise reversion by rapid cardiac activity and possible solutions to the problem by adequate pacemaker design are discussed.  相似文献   
54.
The present study included 17 patients with angina pectoris and coronary artery disease in whom a rate responsive ventricular pacemaker (Medtronic Activitrax) had been implanted. All patients had an exclusively paced rhythm. Single blinded, random, cross-over treadmill tests in the rate responsive pacing mode (VVIR) and in the fixed-rate demand mode (VVI) were performed, with an interval of 4-6 weeks. Mean exercise duration increased by 25% during VVIR pacing. Maximal heart rate increased significantly during VVIR compared to VVI pacing (VVI = 74 +/- 2 bpm, VVIR = 116 +/- 8 bpm, P less than 0.001) as did the rate-pressure product (VVI = 10.850 +/- 1,124, VVIR = 16.628 +/- 2,110, P less than 0.001). Despite improved performance, the number of anginal attacks per week and the nitroglycerin consumption did not show a significant difference between the two pacing modes. It is concluded that rate responsive pacing is beneficial and safe in patients with angina pectoris and coronary artery disease.  相似文献   
55.
Endothelial cell dysfunction in homocystinuria   总被引:10,自引:0,他引:10  
Abstract. This report describes the isolation and culture of venous endothelial cells from the umbilical cord of an obligate heterozygote for homocystinuria. The effect of different sulphur-containing amino acids on the viability and function of these cells was studied and compared with cultured normal endothelial cells. When endothelial cells were cultured in the presence of methionine (10 mmol/l) or homocystine (10 mmol/l), differences occurred between the viability and function of the heterozygote and normal cells in terms of 51Cr release and ability to prevent platelet adherence. The Cr release corrected for spontaneous release increases for the heterozygote cells after incubation for 21 h in the presence of methionine to 81.3% (control cells, range: 0–23.3%, n = 5) and in the presence of homocystine to 141% (control cells, range: 13.5–55.2%, n = 5). The total number of platelets that adhere to confluent monolayers increases for heterozygote cells cultured in the presence of methionine to 0.98 ± 107 platelets cm-2 (normal cells, range: 0.56–0.72 ± 107 platelets cm-2) and in the presence of homocystine to 1.41 ± 107 platelets cm-2 (normal cells, range: 0.94–1±06 ± 107 platelets cm-2). Both normal and control cells were sensitive to homocysteine. This study indicates for the first time what vascular endothelial cells, derived from an obligate heterozygote, are (partly) deficient in cysthathionine synthase and are more susceptible to methionine- and homocystine-mediated injury than normal endothelial cells. Consequently, in homocystinuria, due to dysfunction of the endothelial cells, toxic sulphur-containing amino acids may accumulate in these cells, causing injury of these cells.  相似文献   
56.
  • ? Discharge planning has received much attention in the nursing literature over the past few years, and there has been particular concern over the discharge of older people back into their domestic environment.
  • ? The practical and logistical problems of managing such a discharge are considerable, but in this paper we argue that discharging older people from hospital to care homes is equally problematic, though in different ways.
  • ? This is a neglected area of research, perhaps because discharge into a care home seems to present fewer organizational problems.
  • ? There is, however, an extensive body of literature from a range of different disciplines which suggests that the loss of home and entry into a strange environment can be very stressful.
  • ? This paper outlines this literature and explores the implications for nursing practice.
  相似文献   
57.
To examine the influence of age on the autonomic and electrophysiological correlates of sudden death after myocardial infarction, 223 patients aged <60 and 195 patients aged ≥60 were followed up for a mean of 790 days. The patients had Holter monitoring and a signal-averaged EGG 5–11 days after infarction. A mean ventricular ectopic beat frequency >10 beats/ hour (VE10) was present in 17.0% of young versus 28.2% of old patients (P < 0.01); a low heart heart variability index in 17.9% of young but in 32.3% of old patients (P < 0.001) and late potentials in 17.5% but 32% of young and old patients, respectively (P < 0.01). There was no difference in the incidence of sudden death between young and old patients (3.6% vs 3.1%). However, sudden death accounted for 50%, compared with 24% of all deaths in the young and old groups, respectively (P < 0.01). Sudden death was more closely associated with low heart rate variability and VE10 in the young than in the older group. The predictive values of a heart rate variability index <20 units with VE10 in younger patients were a sensitivity of 50%, a positive predictive accuracy (PPA) of 33% and risk ratio (RR) of 18 (P < 0.001); these values did not reach significance in older patients (16.7%, 4.3% and 1.4%, respectively.) Late potentials had a sensitivity of 50%, a PPA of 12.1%, and an RR of 4.7 in young patients (P < 0.05): the corresponding values in the older group were 80%, 8.9, and 8.4 (P < 0.02). It is concluded that sudden death is a more predominant mode of death and is more strongly associated with lower heart rate variability and with the VE10 incidence in young than in older postinfarction patients. Age should be taken into account when assessing the risk of sudden death after myocardial infarction.  相似文献   
58.
Pressure‐Guided Cryoballoon Pulmonary Vein Isolation. Background: Pulmonary vein (PV) isolation using a balloon‐mounted cryoablation system is a new technology for the percutaneous treatment of atrial fibrillation (AF). Complete PV occlusion during balloon ablation has been shown to predict successful electrical isolation. The aim of this study was to correlate mechanical PV occlusion with changes in a pressure curve recorded at the distal tip of the cryoballoon catheter. Methods and Results: We analyzed 51 PVs in 12 patients (61 ± 6 years old) with paroxysmal AF. At first, PV occlusion via the cryoballoon was documented by changes in the pressure curve. Once the PV is occluded, the pressure curve registered in the vein converts from a left atrial pressure curve to a pulmonary artery pressure curve: the PV wedge curve. Occlusion was then confirmed by transesophageal echocardiography (TEE). Following 2 cryoablation applications, electrical PV isolation was assessed with a circumferential mapping catheter. Under the exclusive guidance of changes in the pressure curve at the tip of the cryoballoon, mechanical occlusion confirmed by TEE was achieved in 47 of 51 PVs (92%). Three PVs required further TEE guidance to achieve occlusion. All 50 occluded veins were electrically isolated after cryoablation. One right inferior vein, which could not be occluded with the balloon, displayed conduction post cryoablation and was isolated by focal ablation. Conclusions: Occlusion and electrical isolation of PVs during cryoballoon ablation can be predicted by the appearance of a PV wedge curve at the tip of the catheter. This new straightforward parameter may facilitate the procedure. (J Cardiovasc Electrophysiol, Vol. 21, pp. 120‐125, February 2010)  相似文献   
59.
Introduction and Aims. A survey was conducted in 2004–2005 to investigate the risk of drug‐related harm among Chinese, Vietnamese, Italian, Pasifika, Arabic‐speaking and Spanish‐speaking communities in Sydney. Design and Methods. A self‐completion questionnaire, available in six languages, was distributed by bilingual field staff. A representative multistage clustered sampling design was used. Comparisons were made with the New South Wales general population using the results from the 2004 National Drug Strategy Household Survey. Results. The obtained sample was 2212 respondents; 50% completed the questionnaire in English. Daily tobacco use was higher than the general population among Vietnamese men (30%), Italian men (22%) and Pasifika men and women (25%). Reported use of alcohol and other drugs was lower than the general population in all six surveyed communities. Of the six communities, Pasifika had the highest rate of short‐term risky drinking (22%). Discussion and Conclusions. Smoking cessation programs should prioritise communities with higher or equal rates of daily smokers compared with the wider New South Wales population. Focus areas vary between the communities, and include increasing help seeking and improving quitting success rates. Short‐term risky drinking was not as prevalent among the surveyed communities; however, results suggest a need for prevention targeting Pasifika communities. Understanding the prevalence of substance use among culturally and linguistically diverse communities provides a crucial foundational component in developing culturally sensitive prevention and treatment programs. These results demonstrate the need for programs to be tailored to the needs and contexts of particular communities, rather than treating those from diverse backgrounds as one homogenous group.[Donato‐Hunt C, Munot S, Copeland J. Alcohol, tobacco and illicit drug use among six culturally diverse communities in Sydney. Drug Alcohol Rev 2012;31:881–889]  相似文献   
60.
徐依峰  张晴  廉靖贤 《职业与健康》2009,25(17):1854-1855
目的了解无锡市锡山区体检人员HBsAg携带情况,结合丙氨酸转氨酶(ALT)及HBeAg分析,探讨HBV感染者与肝功能异常的相关性。方法采用酶联免疫吸附试验(ELISA)法检测HBsAg,对其中部分阳性者进行HBeAg检测,同时用全自动生化分析仪检测血清中ALT。结果2006-2008年92349名体检人员,HBsAg携带率为3.47%,有呈逐年下降的趋势,各年度间差异有统计学意义(Х^2=8.046,P〈0.05);其中1452例HBsAg阳性者中HBeAg阳性的人员ALT异常率为31.79%,与HBeAg阴性人员的ALT异常率14.10%之间差异有统计学意义(Х^2=51.37,P〈0.01)。结论要加强宣传乙型肝炎相关防护知识,对HBsAg阳性者应做乙肝标志物并结合肝功能(ALT)来判断其病情和传染性。  相似文献   
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