Burden of illness among patients with severe aplastic anemia who have had insufficient response to immunosuppressive therapy: a multicenter retrospective chart review study

Annals of Hematology - This study assessed treatment patterns and healthcare resource utilization (HRU) of patients with severe aplastic anemia (SAA) with insufficient response to immunosuppressive...     

Temporal summation and reaction times for detecting gratings

The effects of the duration of presentation of stimuli on the reaction time for detection of gratings of different spatial frequencies were studied. The product of contrast and duration (the contrast energy) was kept constant for each duration. These experiments showed that at near-threshold energies, reaction times did not change with increases in the duration to 15 and 30 msec at low and high spatial frequencies respectively. At high contrast energies,rd this critical duration was identical (15 msec) for both low and high spatial frequencies. The effects of the duration of a linearly increasing front for grating presentation on detection reaction times were also studied. Increases in the duration of the front (to 60 msec) significantly lengthened the reaction time at low spatial frequencies at all contrast levels studied. Conversely, at high spatial frequencies, a significant increase in the reaction time was seen only at high contrast levels. These results suggest that reaction time depends on two types of mechanisms (phasic and tonic) at nearthreshold contrast and one type (phasic) at high contrast.Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 89, No. 10, pp. 1240–1249, October, 2003.     

Norddeutsche Orthop?denvereinigung Berlin, 22.–24. Juni 2000

Die gute Zusammenarbeit mit der Industrie wurde durch die zahlreich vertretenen Firmen und deren Ausstellungsfl?chen dokumentiert, die zu einem Erfahrungsaustausch und zur Diskussion neuer “Trends” einluden sowie auf neue Entwicklungen aufmerksam machten.     

How many pathways determine the speed of grating detection?

Reaction time (RT) for detection of gratings of different spatial frequencies (SF, 0.87-13.87 c/d) and contrast (2-32 times above the detection threshold) was measured. It was found that at low stimulus contrast, 2 and 4 times above the detection threshold, the dependence of mean RT on SF is an "S"-type function with the two plateaus 50-60 ms apart. The standard deviation (SD) increases significantly for SFs within the range 2.60-6.93 c/deg and this coincides with the transition of mean RT from one plateau to another. At higher contrast the dependence of RT on the SF is a monotonically increasing function without any plateau and SD does not demonstrate any extrema within the entire SF-range. The results suggest that RT is determined by two mechanisms (transient and sustained) at low contrast, and by one (transient) mechanism at higher contrasts.