Biomedical subjects

D A Silverstein

Publications and source records attributed to D A Silverstein.

3 recordsLinked to original sources

PubMed1995

Vernier acuity during image rotation and translation: visual performance limits.

Our capacity to detect spatial misalignments a fraction of the distance between retinal receptors in the presence of image motion challenges our understanding of spatial vision. We find that vernier acuity, while robust to image translation, rapidly degrades during image rotation. This indicates that orientation is a critical cue utilized by the visual system in vernier acuity tasks. Moreover, vernier acuity is robust to translational motion only at high target strengths. Vernier acuity for translating 3-dot targets over midrange velocities can be predicted from vernier acuity data derived from static targets of different presentation durations. However, the degradation observed at higher velocities is greater than predicted. The high velocity degradation reveals that performance is limited by a 1 msec asynchrony sensitivity. The moving vernier stimulus appears to constitute an optimal configuration for the visual system to achieve a 1 msec asynchrony sensitivity by making use of an orientation cue.

Cues↗

PubMed1989

Endometrial sampling: analysis of 310 procedures performed by family physicians.

Endometrial sampling has become an accepted office procedure. Safety and clinical usefulness have been well established but not specifically studied in family practices. To address the safety and clinical usefulness of endometrial sampling, a chart review of 310 endometrial sampling procedures performed by practicing family physicians was undertaken. Cases were identified by billing records and chart auditing to assure complete recording of all procedures performed by study practitioners since the beginning of their practices. A prestudy survey revealed that 26% of rural family physicians and none of the urban family physicians in western New York were doing endometrial sampling. Practitioners were doing an average of 1.2 per month. Of the 310 procedures 14.5% were unsuccessful because of cervical stenosis or inadequate sample. There were no reported complications, and three cases of endometrial carcinoma were discovered. Endometrial sampling is safe and clinically useful when performed by family physicians.

Adolescent↗

PubMed1988

Fever. What to do and what not to do.

Body temperature is monitored and regulated by the anterior hypothalamus, which acts as a thermostat by altering the balance of heat production and loss via the sympathetic nervous system. Fever results when the thermoregulatory set point in the hypothalamus is shifted upward. Fever is a part of the acute phase response, a generalized reaction to infection or inflammation initiated by interleukin-1 (IL-1). Prostaglandin E2 is the neural mediator of fever induced by IL-1, so fever can be suppressed by drugs that interfere with prostaglandin synthesis. Fever can be reduced by peripheral cooling, but the preferred method is treatment with antipyretic drugs. Although the host's response to infection is enhanced by small increases in body temperature, antipyretic treatment does not appear to interfere with recovery in humans.

Acetaminophen↗