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991.
Left ventricular systolic torsion and exercise in normal hearts.   总被引:2,自引:0,他引:2  
This study examines the use of a novel 2-dimensional echocardiographic technique to measure left ventricular (LV) systolic torsion or twist in normal human hearts during maximal exercise. The effects of dynamic exercise on LV twist have not previously been determined. LV twist was measured in 25 healthy human control patients before and after maximal treadmill exercise. LV end-systolic volume decreased and LV ejection fraction increased in a predictable manner. Systolic twist increased by 8.4 +/- 2.8 degrees (86%). Twist is believed to store potential energy and to play an important role in generating diastolic suction. The increase in twist observed may play an important role in facilitating LV diastolic filling during maximal exercise.  相似文献   
992.
A recent analysis of the American Association of Poison Control Centers database, showed that poisonings from toxins not usually considered amenable to extracorporeal purification (“non‐classic toxins” such as ethanol and tricyclic antidepressants) continue to be reported. This publication investigates factors that may explain these findings. Our results suggest that: 1) the relatively high absolute number of ECTR performed for non‐classic toxins may simply reflect the large number of exposures to these toxins, 2) poisoning from another toxin may have been the reason for ECTR initiation in some exposures to non‐classic toxins, 3) poisoning from non‐classic toxins may receive ECTR for purposes other than toxin removal, and 4) the decisional threshold to initiate ECTR may be lower for non‐classic toxins because of heightened toxicity.  相似文献   
993.

Background

Prospective studies have established the mycophenolate mofetil (MMF) efficiency in childhood idiopathic nephrotic syndrome (INS) but reports on the long-term outcome are lacking. Moreover, the search for factors influencing its efficiency would be useful to define its place among the other treatments.

Methods

We performed a monocentric retrospective study including 96 children with steroid-dependent INS followed for 4.7 years (median) (IQ 3–6) after the onset of MMF treatment. The characteristics of responder patients (n?=?74), as defined by a 50 % decrease of relapse rate and/or a 60 % decrease of steroid dose, and of non-responder patients (n?=?22) were compared by univariate analysis and multivariate logistic regression.

Results

Withdrawal of prednisone was achieved in 48/96 patients after a median duration of 18.1 months (IQ 7.8–30.0) of MMF. Only 26/48 patients did not relapse under MMF alone. After MMF was stopped in these patients, only six remained in remission without any treatment at last follow-up. Responders had a shorter time to remission at the first flare (9.5 vs. 15 days, p?=?0.02), a shorter disease duration prior to the onset of MMF (22.2 vs. 94.5 months, p?=?0.001), and were younger at the MMF initiation (6.7 vs. 10.1 years, p?=?0.02) than non-responder patients. The age of MMF initiation was an independent factor associated with efficiency (OR?=?0.80, 95 % CI [0.69, 0.93], p?<?0.01).

Conclusions

MMF is more efficient in young patients treated early in the disease course. Nevertheless, MMF has no remnant effect while nearly all patients relapsed after withdrawal of the drug.
  相似文献   
994.

Background

Left ventricular dysfunction is an important co-morbidity of end-stage renal disease (ESRD) and is associated with a poor prognosis in the adult population. In pediatric ESRD, left ventricular function is generally well preserved, but limited information is available on early changes in myocardial function. The aim of this study was to investigate myocardial mechanics in pediatric patients with ESRD using speckle-tracking echocardiography (STE).

Methods

Echocardiographic studies, including M-mode, tissue Doppler imaging (TDI) and STE, were performed in 19 children on dialysis, 17 transplant patients and 33 age-matched controls. Strain measurements were performed from the apical four-chamber and the short axis view, respectively.

Results

The interventricular and left ventricular posterior wall thickness was significantly increased in dialysis and transplant patients compared to healthy controls. No significant differences were found in shortening fraction, ejection fraction and systolic tissue Doppler velocities. Dialysis and transplant patients had a decreased mean longitudinal strain compared to healthy controls, with a mean difference of 3.1 [95 % confidence interval (CI) 2.0–4.4] and 2.7 (95 % CI 1.2–4.2), respectively. No differences were found for radial and circumferential strain.

Conclusions

Speckle-tracking echocardiography may reveal early myocardial dysfunction in the absence of systolic dysfunction measured by conventional ultrasound or TDI in children with ESRD.
  相似文献   
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Purpose

The impact of chemotherapeutic sequelae on long-term quality of life (QoL) for survivors of malignant sacrococcygeal teratoma (SCT) is unknown. The incidence of chemotherapeutic toxicity in patients treated for malignant SCT and possible effects on the QoL were analyzed.

Methods

Retrospective chart review of patients ≥18 years treated for SCT in the Netherlands was performed. Present QoL was evaluated using the SF-36 questionnaire. The results of survivors of malignant SCT were compared to those of patients treated for benign SCT.

Results

Fifty-one of 76 traceable patients consented to participate. The results of 47 (92.2 %), 9 men and 38 women (median age 25.4 years, range 18.3–41.2), were analyzed. Eleven had been treated for malignancy; 63.6 % suffered from at least one chemotherapeutic sequel with hearing loss as the most common one. Results for both groups were similar on all but one SF-36 subcategory; those treated for malignant tumor scored significantly lower on the subcategory physical functioning (p = 0.02).

Conclusion

Despite the high incidence of chemotherapeutic sequelae among survivors of malignant SCT, their QoL does not differ from that of those treated for benign SCT. Even though their physical functioning is restricted, daily activities and psychosocial functioning of survivors of malignant SCT are not restricted.
  相似文献   
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