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141.
OBJECTIVES: (1) To study the correlation among conventional clinical and laboratory parameters and the relation between the number of lymphocytes and neutrophils (L/N) in cell suspensions from peripheral blood of patients with juvenile idiopathic arthritis (JIA). (2) To evaluate the L/N relation of JIA patients after an 8 year follow-up period. METHODS: Fifty-one JIA patients (25 female, disease course: 19 systemic, 15 polyarticular, 17 pauciarticular) were enrolled in the study. To measure the L/N relation, we used Boyum's method: The leucocyte separation was done by centrifugation of peripheral blood on Ficoll-Hypaque (FH) gradient, and the number of lymphocytes, monocytes, and neutrophils in 500 cells was determined. The following clinical and laboratory parameters were evaluated: disease activity, number of active and limited joints, functional capacity, erythrocyte sedimentation rate (ESR), and C reactive protein (CRP). Twenty-four healthy children were used as controls. We also studied 13/51 patients from our Pediatric Rheumatology Unit who had been evaluated by the same method 8 years before. RESULTS: We observed the lowest L/N relation in patients with active disease, especially those with polyarticular course. A statistical correlation was also observed with the acute-phase reactants (ESR and CRP, p < 0.05). The majority of patients who had presented a low L/N relation at the first evaluation (8 years before) had a worse outcome. CONCLUSION: The measure of L/N relation from peripheral blood could be used as an auxiliary tool in the assessment of the activity and outcome of JIA patients, especially at disease onset.  相似文献   
142.
BACKGROUND: Inappropriate therapy from supraventricular tachyarrhythmias (atrial fibrillation [AF] and sinus tachycardia [ST]) in patients with implanted cardioverter defibrillators is a major challenge. We tested the performance of stability algorithms from 3 manufacturers for episodes of inappropriate therapy delivered because of AF and an onset algorithm for all episodes of inappropriate therapy caused by ST. METHODS: Therapy was classified as caused by ventricular tachycardia (VT), ST, or AF from review of stored intracardiac electrograms, history, clinical information, and R-R data before study inception. By using 30 to 60 R-R intervals before therapy, sensitivity and specificity for a family of stability values and percentage of onset values were calculated for each manufacturer and receiver operating characteristic curves generated. RESULTS: Of the 217 patients monitored, 62 (29%) received inappropriate therapy, and 40 had complete R-R information available. Of the 40 patients, 21 patients received therapy for AF, 19 for ST, and 1 patient for noise; 15 (38%) also received appropriate therapy for VT. We analyzed 83 episodes of VT from 18 patients, 94 episodes of AF from 21 patients, and 56 episodes of ST from 19 patients. Specificity, in the clinically relevant sensitivity range of >/=95%, was comparable across manufacturers at about 40%. An onset value of 80% was associated with 91% sensitivity and 95% specificity for the specific algorithm tested. CONCLUSIONS: Inappropriate therapy is a common problem in implantable cardiac defibrillators. The performance of the stability algorithms used to differentiate AF from VT was less than ideal, though comparable across manufacturers. The onset algorithm accurately differentiates ST from VT.  相似文献   
143.
BACKGROUND: Evidence for the proper management of ischemic heart disease (IHD) in the general population is well established, but recommendations for physical activity and competitive sports in these patients are scarce. The aim of the present paper was to provide such recommendations to complement existing ESC and international guidelines on rehabilitation and primary/secondary prevention. DESIGN AND METHODS: Due to the lack of studies in this field, the current recommendations are the result of consensus among experts. Sports are classified into low/moderate/high dynamic and low/moderate/high static, respectively. RESULTS: Patients with a definitive IHD and higher probability of cardiac events are not eligible for competitive sports (CS) but for individually designed leisure time physical activity (LPA); patients with definitive IHD and lower probability of cardiac events as well as those with no IHD but with a positive exercise test and high risk profile (SCORE > 5%) are eligible for low/moderate static and low dynamic (IA-IIA) sports and individually designed LPA. Patients without IHD and a high risk profile+ a negative exercise-test and those with a low risk profile (SCORE < 5%) are allowed all LPA and competitive sports with a few exceptions. CONCLUSIONS: Individually designed LPA is possible and encouraged in patients with and without established IHD. Competitive sports may be restricted for patients with IHD, depending on the probability of cardiac events and the demands of the sport according to the current classification.  相似文献   
144.
Background

Resistance training has proven to be an excellent method for counteracting aging physical dysfunctions. However, its application in the liquid environment is not yet fully elucidated.

Aim

To investigate the effects of water-based resistance training (WBRT) with the concentric phase performed as fast as possible, compared to conventional resistance training (CRT), on physical functional capacity, muscle strength, and body composition in older women.

Methods

Thirteen healthy older women participated in the WBRT and 11 in the CRT. Estimation statistics focused on the effect size of the experiment/intervention were used. We also analyzed the intervention effect based on the percentage delta between WBRT and CRT.

Results

The WBRT group showed a negative large effect (d?=?? 0.922; p?=?0.0274) for the timed up and go, and a large effect for chair rise in 30″ and the elbow flex test (d?=?1.58; p?=?0.0012; d?=?2.8; p?=?0.01) respectively. Intervention comparisons based on the delta percentage between WBRT and CRT presented an intermediate effect (d?=?0.606; p?=?0.157) for the stair climb, a large effect (d?=?0.988; p?=?0.0282) for the timed up and go, and a large negative effect [d?=?? 1.32 (90.0% CI ? 1.92, ? 0.646); p?=?0.0038] for the elbow flex test. Concentric extensor-flexor peak torque (60°/s) showed an intermediate effect (d?=?0.749; p?=?0.0876; d?=?0.65; p?=?0.122 respectively). Body fat (%) demonstrated an intermediate effect (d?=?0.523; p?=?0.234).

Conclusion

WBRT with the concentric phase performed as fast as possible was able to improve physical functional capacity and maximal knee extension strength of older women.

  相似文献   
145.
Comparison of two clinical scales for causality assessment in hepatotoxicity   总被引:15,自引:0,他引:15  
This study was performed to compare the assessments of drug-induced liver injury obtained with 2 methods, the Council for International Organizations of Medical Sciences (CIOMS) scale and the recently validated Maria & Victorino (M&V) clinical scale, in cases submitted to a registry of hepatotoxicity. A total of 215 cases of hepatotoxicity reported with a structured reporting form were evaluated by 3 independent experts. Because of the use of multiple drugs, 228 ratings were generated. The probability of the diagnosis was classified as definitive, probable, possible, unlikely, or excluded, and evaluated for consistency with a weighted kappa statistical test. Absolute agreement between the 2 scales was observed in 42 cases (18%, weighted kappa 0.28) with disagreement of 1 level in 108 cases (47%), and of 2 levels in 70 cases (31%). The best correlation between the 2 scales was obtained for drug-induced liver injury involving a suggested immunoallergic mechanism: the disagreement was 1 level or less in 72% of the cases (34 of 48), compared with 60% of the cases (85 of 141) that involved a presumed idiosyncratic metabolic mechanism. The lowest agreement (6%) was observed in cases with evidence of cholestasis. No agreement was found in cases of fulminant hepatitis or death. The CIOMS scale showed better discriminative power and produced assessments closer to those of specialists. The performance of the M&V scale was poor in reactions with long latency periods (i.e., amoxycillin/clavulanic acid), evolution to chronicity after withdrawal (cholestatic pattern), or death.  相似文献   
146.
Right ventricular involvement is a typical characteristic of Chagas' disease, and it has been described especially in the early stages of the disease. However, the role of right ventricular dysfunction in cardiac failure due to Chagas' cardiomyopathy has not been well established. Seventy-four patients with positive serology tests for Trypanosoma cruzi and Chagas' dilated cardiomyopathy characterized by left ventricular dilatation and systolic dysfunction were studied. Clinical history, physical exam, ECG, chest X-ray and Doppler echocardiogram with color flow mapping were obtained in all. Mean age was 47.5+/-12.9 and 51 were males (69%). Sixty-five patients (88%) were in NYHA functional classes I and II. Mild systolic dysfunction was present in 35 (47%) while in 18 (24%), dysfunction was moderate and in 21 (28%) it was severe. In 43 patients (58%), only the left ventricle was involved by echocardiographic criteria; the remaining 31 patients (42%) showed biventricular involvement. No patient had isolated involvement of the right ventricle. Greater dilation of the right ventricle was associated with larger diastolic (p<0.002) and systolic (p<0.001) diameters of the left ventricle. Systolic pulmonary artery pressure was obtained non-invasively in 54 patients. Pulmonary hypertension was associated with right ventricular dilation (p<0.005) and with systolic dysfunction of the left ventricle (p<0.001). In this group of patients with Chagas' dilated cardiomyopathy, right ventricular dysfunction was present when there was associated and significant involvement of the left ventricle and with higher levels of pulmonary pressure.  相似文献   
147.
Severe chronic damage to the heart and gastrointestinal tract in patients with Chagas' disease are often observed 10-20 years after the acute phase. The course of long-lasting infection with the Colombian strain of Trypanosoma cruzi was studied in seven rhesus monkeys infected for 15-19 years. Subpatent parasitemia was detected in all studied animals, using hemoculture (two of seven), artificial xenodiagnosis (three of seven), and a polymerase chain reaction PCR (six of six). High titers of specific IgG antibody to T. cruzi persisted throughout the chronic phase of infection. Abnormal electrocardiographic (three of six) and echocardiographic (one of six) patterns detected in the T. cruzi-infected monkeys were possibly related to parasite-triggered myocardial damage. The results suggest that rhesus monkeys experimentally infected with T. cruzi, besides reproducing the acute phase of Chagas' disease, also develop chronic chagasic cardiomyopathy.  相似文献   
148.
149.
Implantable cardioverter-defibrillators (ICDs) are an important nonpharmacological option in the treatment of malignant ventricular arrhythmias. Technological advances in current devices permit nonthoracotomy implantation with transvenous lead systems using biphasic shocks. Decreasing device size has resulted in pectoral implantation. Battery longevity is still short in comparison with that of pacemakers. Lead failure rates as well as pacing thresholds are significantly higher than those for cardiac pacing lead systems. Other complications of ICD systems include infection, perforation, and thrombosis. The long-term performance of nonthoracotomy lead systems for ICD devices has now been extensively studied. Sudden death recurrence rates for these systems are less than 2% in 3 years and less than 5% at 5 years. Clinical trials with both monophasic and biphasic systems show a high degree of prevention of sudden death. Comparison of ICD outcome with that of drug therapy in three large retrospective studies and two small prospective randomized trials favors improved survival and sudden death prevention with device therapy. However, these studies need corroboration from large prospective trials. Two large prospective trials, CIDS and the AVID study, are now in progress to address this issue.  相似文献   
150.
PURPOSE OF REVIEW: The crystal-induced arthropathies are characterized by self-limiting episodes of acute inflammation and chronic tissue damage. This review summarizes recent advances in the understanding of the cellular responses to monosodium urate, calcium pyrophosphate dihydrate and basic calcium phosphate crystals. RECENT FINDINGS: Factors such as the myeloid related proteins, endothelin-1 and the complement membrane attack complex have been recently identified as mediators of acute crystal-induced inflammation. In addition, signalling pathways involved in both acute inflammation and tissue damage in crystal arthropathies have been further clarified. The potential of macrophage-derived transforming growth factor beta1 to play a key role in the resolution phase of acute gout has also been demonstrated. SUMMARY: Recent work has provided new insights into the regulation of both acute and chronic articular responses to inflammatory microcrystals. Further analysis of these responses may identify potential therapeutic targets for management of the crystal-induced arthropathies.  相似文献   
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