David Ascher

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OBJECTIVE To determine the minimum volume of blood and the absolute number of organisms required for detection of bacteremia and fungemia by an automated colorimetric blood culture system (BacT/Alert, Organon Teknika). DESIGN Common neonatal pathogens, Escherichia coli, Streptococcus agalactiae (group B streptococcus (GBS): one American Type Culture(More)
Several models have been proposed for how the brain measures velocity from the output of motion-energy units. These models make some unrealistic assumptions such as the use of Gabor-shaped temporal filters, which are non causal, or flat spatial spectra, which are invalidated by existing data. We present a Bayesian model of velocity perception, which makes(More)
We report four fatal cases of amebic encephalitis in children caused by the free-living pathogenic ameba Balamuthia mandrillaris. The clinical course ranged from subacute to fulminant. Provisional diagnoses were made either shortly before death or postmortem by an indirect immunofluorescent antibody test. Although the four cases occurred in different(More)
Bartonella (Rochalimaea) henselae causes a variety of diseases, including bacillary angiomatosis, peliosis hepatis, lymphadenitis, aseptic meningitis with bacteremia, and cat-scratch disease (CSD). Cases of B. henselae-related disease were collected from September 1991 through November 1993. Patients with suspected CSD, unexplained fever and lymphadenitis,(More)
Inhaled corticosteroids (ICS) are drugs of choice for persistent asthma. Less than 500 µg/d of fluticasone are believed to be safe. We found 92 cases of adrenal suppression in PubMed; among these cases there were 13 children who took 500 µg/d or less of fluticasone. Adrenal insufficiency was diagnosed in a 7-year-old boy on 460 µg ICS for 16 months, with a(More)
Previous studies of the accuracy of rapid in-office tests for group A Streptococcus had disparate results, ranging from a sensitivity of 70% to more than 90%. The sensitivity and specificity of 3 commercially available Strep A tests were determined in 2 private pediatric office settings. Acceava Strep A, Genzyme OSOM Strep A, and the Quidel QuickVue Strep A(More)
A total of 180 patients with diarrhea, 6 years and below, were seen and evaluated in our pediatric clinic during the months of July to December, 1986. A bacterial pathogen was isolated from the stools in 24/180 (13%). The best historical factors for predictive accuracies were abrupt onset, no vomiting before the onset of diarrhea, and greater than four(More)