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PURPOSE: A significant number of children with posterior urethral valves (PUVs) have chronic renal failure due to tubulointerstitial damage. Activation of the renin-angiotensin system is known to inflict this injury. We investigated the role of plasma renin activity (PRA) in patients with PUVs and sought to establish a relationship between renal damage and PRA. MATERIALS AND METHODS: The records of patients with PUVs were reviewed regarding the time of valve ablation, serum creatinine, scars, grade of reflux and glomerular filtration rate (GFR). PRA was measured before and after valve ablation. RESULTS: A total of 25 patients had PUVs (mean age 3.2 +/- 2.4 years, mean period of observation 4.5 +/- 1.2 years). Mean PRA was increased before valve ablation in all patients irrespective of age, and decreased after ablation. Of 25 patients 14 (56%) had renal damage, with a mean PRA of 36 +/- 4.5 ng/ml per hour compared to 26 +/- 8.2 ng/ml per hour in patients with normal renal function (chi-square 4.2 p = 0.01). Of the 14 patients with renal damage 9 (64%) had normal GFR at age 1 year but increased PRA. Of these 14 patients the accepted criteria for renal damage of increased serum creatinine, high grade reflux, scars and decreasing GFR were present in only 6 (43%), 3 (21%), 2 (14%) and 4 (29%), respectively. PRA was increased in all 14 cases. CONCLUSIONS: PRA was increased before valve ablation and decreased after ablation. It is increased in patients with early renal damage. Our preliminary observations indicate that PRA may be helpful in identifying patients with early renal damage.  相似文献   
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The present study was conducted to find the prevalence of Extended spectrum b Lactamase (ESBL) producing strains of Klebsiella pneumoniae (K. pneumoniae) and Escherichia coli (E. Coli) in different clinical samples received at the Department of Microbiology, Medical College Baroda. A total of 187 clinical isolates (106 of K. pneumoniae and 81 of E. Coli) were tested for resistance to any one of the three Third generation cephalosporins (3GC) namely cefotaxime, ceftazidime and ceftriaxone. 100 isolates (57 of K. pneumoniae and 43 of E. Coli) were found to be resistant to at least one of the 3GC tested. These were then tested for ESBL production by Double Disc Diffusion Synergy Test (DDST) using Ceftriaxone, Ceftazidime, and Cefotaxime along with Augmentin as well as by the MIC reduction test. ESBL was detected in 53 isolates (33 K. pneumoniae and 20 E. coli). Using the interpretative guidelines of the NCCLS, 24% to 27% of the ESBL isolates would have been reported to be susceptible to the 3GC by routine antimicrobial susceptibility methods. DDST was found to be a useful, simple and cost effective test for the detection of ESBL producing strains.  相似文献   
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Low voltage energy source is not free from danger. An exceptionally rare and peculiar mode of facial blast injury is reported. The blast took place silently in the mouth of a 15-year-old boy, due to short-circuiting of wires connected to a12-volt car battery while peeling off insulation with the intent of running a musical instrument. Airway compromise due to soft tissue injury produced further problem during tracheostomy. Emergent airway management is discussed. Post-healing sequel resulted in loss of voice and prevented normal oral feeding. The case report emphasizes need for education to public in handling low voltage energy source.  相似文献   
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Deb P  Sharma MC  Gaikwad S  Tripathi M  Chandra PS  Jain S  Sarkar C 《Neurology India》2005,53(2):156-60; discussion 160-1
BACKGROUND: Rasmussen encephalitis (RE) is a chronic epileptic disorder of unknown etiology, and is clinically characterized by progressive neurological deterioration, focal seizures often progressing to intractable epilepsy, cognitive decline and hemispheric atrophy. AIMS: We report the spectrum of neuropathological changes seen in RE, and discuss the evolutionary mechanisms of this disease. MATERIALS AND METHODS: Surgically obtained specimens from RE patients diagnosed during 2002-2004 at this institute were evaluated for the presence and extent of different histopathological features of RE. The H&E and immunohistochemistry stained slides were also evaluated for the type and distribution pattern of inflammatory infiltrates, along with a semiquantitative evaluation for the severity of inflammation. RESULTS: Four cases of RE were admitted during the study period, all of which presented with partial seizures with successive deterioration to intractable epilepsy. The age at onset varied between 5 and 10 years (mean 7.8 years), with three male and one female patients. Subsequently, all four patients underwent hemispherotomy. Histopathological features of perivascular lymphocytic infiltrate, neuronal loss, microglial nodules, and reactive astrocytosis, with or without evidence of neuronophagia confirmed a diagnosis of RE. These cases also had varying degrees of T-cell-rich (CD3-positive) inflammatory infiltrates and CD68-immunopositive microglial proliferation. It was observed that the severity of inflammation had a trend to inversely correlate with the duration of symptoms. CONCLUSION: It is proposed that an accurate evaluation and histopathological grading of these lesions may possibly have a role in patient prognostication.  相似文献   
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BACKGROUND AND OBJECTIVE: To examine the calibration of the prognostic system Acute Physiology and Chronic Health Evaluation Score (APACHE II) regarding hospital mortality and predicting weaning outcome after long-term mechanical ventilation of the lungs. METHODS: Prospective observational cohort study performed in a respiratory intensive care unit including 246 patients whose lungs were ventilated for 42.1+/-37.8 (median 30) days in the referring hospital. APACHE II (24 h after admission to our respiratory intensive care unit) and the cause of respiratory failure, underlying disease, prior duration of mechanical ventilation and gender were recorded. The predictive power was evaluated with sensitivity and specificity for different cut-off points and summarized in a receiver operating characteristic curve. RESULTS: No difference was found between survivors (APACHE II 16.0+/-4.3) and non-survivors (APACHE II 16.9+/-5.1). In a mean time of 8.0+/-10.3 days, 146 patients (59.3%) were successfully weaned (APACHE II 15.2+/-3.5). One-hundred patients (40.7%) were considered unweanable (APACHE II 17.7+/-5.3). Recalibration of APACHE II to predict weaning failure was possible, resulting in an area under the receiver operating characteristic curve (AUC) of 0.638. Furthermore the AUC improved to 0.723 by changing the weights of selected APACHE items and introducing external factors. Diagnostic accuracy fell from group with mechanical ventilation < or =25 days (AUC 0.770) to group with mechanical ventilation >50 days (AUC 0.517). CONCLUSIONS: APACHE II did not predict hospital mortality after long-term mechanical ventilation of the lungs. Not the original APACHE II but a recalibrated and adapted APACHE II can be useful to predict weaning outcome in patients with less than 25 days of prior lung ventilation.  相似文献   
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