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Comparative clinical outcomes after exposure to alternate low osmolar contrast media (LOCM) during invasive coronary angiography (ICA) and/or percutaneous coronary intervention (PCI) have been incompletely examined. From a retrospective multicenter observational study, we identified 107,994 adults without previous hemodialysis undergoing ICA and/or PCI with iohexol, iopamidol, or ioversol. We created a propensity score for contrast media type using age, gender, coverage status, route of hospitalization, illness severity, physician specialty, co-morbidities, and procedure type. Propensity matching was performed in a 1:1 fashion for iohexol (n = 10,204) and iopamidol (n = 10,204) and in a 1:1 fashion for iohexol (n = 19,482) and ioversol (n = 19,482). Groups were examined for differences in in-hospital mortality or subsequent hemodialysis, length of stay, and 30-day readmission for contrast-induced nephropathy (CIN). Compared to patients exposed to iohexol, no differences were observed for patients exposed to iopamidol or ioversol for in-hospital hemodialysis (0.5% vs 0.4%, p = 0.45; 0.3% vs 0.5%, p = 0.05), in-hospital mortality (0.7% vs 0.6%, p = 0.60; 0.5% vs 0.6%, p = 0.42), or composite hemodialysis or mortality (1.1% vs 1.0%, p = 0.58; 0.8% vs 1.0%, p = 0.06); for hospital length of stay (2.9 ± 2.7 vs 2.9 ± 2.7 days, p = 0.05; 2.8 ± 2.6 vs 2.9 ± 3.1 days, p = 0.35); or for 30-day readmission for CIN (0.1% vs 0.1%, p = 0.82; 0.1% vs 0.1%, p = 0.52). In conclusion, for patients undergoing ICA and/or PCI exposed to alternate LOCM, in-hospital death, need for hemodialysis, or readmission for CIN are uncommon, with no apparent clinical advantage among LOCM agents.  相似文献   
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Imaging surgical epilepsy in children   总被引:1,自引:0,他引:1  
Introduction Epilepsy surgery rests heavily upon magnetic resonance imaging (MRI). Technical developments have brought significantly improved efficacy of MR imaging in detecting and assessing surgical epileptogenic lesions, while more clinical experience has brought better definition of the pathological groups.Discussion MRI is fairly efficient in identifying developmental, epilepsy-associated tumors such as ganglioglioma (with its variants gangliocytoma and desmoplastic infantile ganglioglioma), the complex, simple and nonspecific forms of dysembryoplastic neuroepithelial tumor, and the rare pleomorphic xanthoastrocytoma. The efficacy of MR imaging is not as good for the diagnosis of focal cortical dysplasia (FCD), as it does not necessarily correlate with histopathological FCD subtypes and does not show the real extent of the dysplasia which may even be missed in a high percentage of cases. Further developments with better, multichannel coils, higher magnetic fields, specific sequences, and different approaches (such as diffusion tensor imaging) for depicting the structural abnormalities may hopefully improve this efficacy. A general review of the MR features of the diverse pathologies concerned with epilepsy surgery in the pediatric context is provided with illustrative images.  相似文献   
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Previous beat contraction history, in which the performance of the left ventricle on any one beat is influenced by the mechanical events of the previous beat, may be important in the beat-to-beat regulation of left ventricular performance in the intact cardiovascular system. Prior studies of this phenomenon have established that mechanical events of the previous beat influence the function of the current beat, but it is not known whether the important mechanical influence is exerted by previous beat ejection or previous beat pressure. In addition, the magnitude of the effect of previous beat contraction history on left ventricular performance is unknown. To make these determinations, we performed experiments in six isolated rabbit left ventricle preparations buffer perfused at 30 degrees C. Left ventricular pressure and volume were controlled precisely with a servo-controlled linear motor system. After steady-state ejecting conditions were established by clamping left ventricular ejection pressure at 60% of peak isovolumic pressure, single test beats, which were pressure clamped at 40%, 60%, 80%, and 100% of peak isovolumic pressure, were introduced and followed by an isovolumic reference beat. As the level of pressure clamp decreased from 100% to 40%, developed pressure on the isovolumic beat following the single test beats increased from 139 +/- 15 (mean +/- SD) to 151 +/- 13 mm Hg. Similarly, peak positive left ventricular dP/dt increased from 1,718 +/- 209 to 1,864 +/- 181 mm Hg.sec-1 (both p less than 0.01). Multiple regression analysis showed that this increase in left ventricular function was related to previous beat ejection but not to previous beat pressure load or relaxation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Smoking deception is often ignored, but is important in health care. In this trial it was assessed at both study entry and outcome. At study entry, 1,044 males at a primary care clinic were asked smoking status and tested for breath carbon monoxide (CO). Of self-reported non-smokers, 57/402 (14%) were actually smokers, as were 59/251 (24%) of self-reported ex-smokers. The self-reported smokers (n=387) entered a randomized, controlled trial where the intervention comprised four questions on knowledge and beliefs about smoking, standardized verbal advice against smoking, and a leaflet. At follow-up, subjects were also questioned about beliefs. Follow-up was difficult, but 191/387 (49%) attended at three or six months. Of 27 who claimed to have quit, 6 (22%) were deceivers and 21 were confirmed quitters. Cessation did not differ between intervention and control groups. Overall confirmed cessation at six months was 16/387 (4.1 %). Confirmed quitters were significantly lighter smokers than deceivers and still smokers. There were non-significant trends between the outcome groups whereby deceivers had least knowledge and most lay beliefs, and quitters had most knowledge and fewest lay beliefs. The lay beliefs may prevent some smokers from quitting.  相似文献   
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