PubMed Health⌕ Search

Biomedical subjects

A Blake

Publications and source records attributed to A Blake.

At least 19 recordsLinked to original sources
PubMed1992

Factors associated with adherence to breast cancer screening among working women.

This study identified sociodemographic, knowledge, attitude, and social influence correlates of obtaining mammograms among employed women age 40 and over. Telephone interviews were conducted with 798 women who worked at 39 different work sites. Eighty-four percent of respondents had ever had a mammogram, and 72% had had one at the recommended interval for their age group. The only personal characteristic that was associated with past mammography use was having a co-worker, friend, or relative with a history of breast cancer. Logistic regression analyses indicated that a doctor's advice to have a mammogram, knowledge of screening guidelines, knowing someone with breast cancer, and the beliefs that mammography is effective and that mammography is necessary in the absence of symptoms were associated independently with past use of mammography. Three factors contributed independently to explaining adherence to mammography guidelines: younger age, knowledge of guidelines for one's own age group, and the belief that breast cancer is curable. The findings suggest that emphasizing the recommended guidelines, the need for and benefits of mammography in educational programs, and offering low-cost or free mammography at the workplace, can further increase appropriate utilization among working women.

Age Factors↗
PubMed1991

Shape from specularities: computation and psychophysics.

Images of artificial and natural scenes typically contain many 'specularities' generated by mirror-like reflection from glossy surfaces. Until fairly recently computational models of visual processes have tended to regard specularities as obscuring underlying scene structure. Mathematical modelling shows that, on the contrary, they are rich in local geometric information. Recent psychophysical findings support the notion that the brain can apply that information. Our results concern the inference of 3D structure from 2D shaded images of glossy surfaces. Stereoscopically viewed highlights or 'specularities' are found to serve as cues for 3D local surface-geometry.

Cues↗
PubMed1991

Fused rhabdomeres (fur) in Drosophila: an eye mutation that alters rhabdomere morphology and retinal function.

In the Drosophila compound eye, the photoreceptor cells are organized in highly precise units, the ommatidia. In each photoreceptor cell, the primary photopigment, opsin, is contained in the rhabdomere, an ordered array of densely packed microvilli. A genetic and phenotypic analysis of a new X-linked. P element-induced mutation, fur, (fused rhabdomeres) is presented. Light and electron microscope studies show that mutations at the fur locus result in the fusion of the adjacent rhabdomeres in the developing eye and the fusion takes place during the pupal stage of eye development. Electrophysiological experiments indicate that the fur mutant photoreceptors have reduced sensitivity to light and lack a PDA (prolonged depolarizing afterpotential), a response characteristic of normal photoreceptor cells. Recombination and deficiency mapping localize fur to the proximal region of the X chromosome. Reversion analysis indicates the fur mutant is the result of a P element insertion. These studies suggest that the fur locus encodes a gene that has specific roles in rhabdomere morphogenesis and retinal function.

Animals↗
PubMed1990

Consumption of olive oil, butter, and vegetable oils and coronary heart disease risk factors. The Research Group ATS-RF2 of the Italian National Research Council.

The cross-sectional association between consumption of various fats (eg, butter, olive oil, and vegetable oil) and risk factors for coronary heart disease was analyzed in a sample of 4903 Italian men and women 20 to 59 years of age. The intake of fats was ascertained by an interviewer-administered questionnaire. Increased consumption of butter was associated with significantly higher blood pressure and serum cholesterol and glucose levels for men; in women only the association with glucose reached statistical significance. In both sexes consumption of olive oil and vegetable oil was inversely associated with serum cholesterol and glucose levels and systolic blood pressure. These findings were adjusted for confounding effects of other risk factors for cardiovascular disease. These cross-sectional findings from a large population sample suggest that consumption of butter may detrimentally affect coronary risk factors, while polyunsaturated and monounsaturated fats may be associated with a lower coronary risk profile.

Adult↗
PubMed1990

Does the brain know the physics of specular reflection?

Images of artificial and natural scenes typically contain many highlights generated by mirror-like reflection from glossy surfaces. Until recently, computational models of visual processes have tended to regard highlights as obscuring the structure of the underlying scene. The truth is that, on the contrary, highlights are rich in local geometric information. Here we report that the three-dimensional appearance of a highlight on a computer-simulated stereoscopic curved surface affects observers' judgment of surface gloss. We also show that the 3-D appearance of a highlight affects the perception of surface curvature--that is, it can force an ambiguous convex-concave figure to change state. We thus conclude that human visual analysis seems to employ a physical model of the interaction of light with curved surfaces, a model firmly based on ray optics and differential geometry.

Brain↗
PubMed1990

Diet and coronary heart disease risk factors in a population with varied intake. The Research Group ATS-RF2 of The Italian National Research Council.

The relationship between consumption of foods high in saturated fats and cholesterol and a number of coronary heart disease risk factors (blood pressure, serum glucose, serum cholesterol, and triglycerides) was analyzed in a large sample (4,917) of Italian men and women, ages 20-59 years. The dietary habits of the participants were ascertained with a food frequency questionnaire. Intake of atherogenic foods (foods high in cholesterol and saturated fats) was evaluated for each participant. In both sexes, systolic blood pressure, serum glucose, and serum cholesterol increased with higher consumption of atherogenic foods. These findings were independent of any possible confounding effect of age, adiposity, alcohol intake, and cigarette smoking. The present article confirms previous findings that consumption of foods high in saturated fats and cholesterol is associated with an increased risk for atherosclerosis.

Adult↗
PubMed1988

Pathophysiological sequelae of hepatic artery ligation: an experimental study.

The effects of ligation of the proper hepatic artery were studied in 40 rats. The serum transaminase and bilirubin levels were elevated significantly at 24 h following surgery but had returned to normal by the 7th postoperative day. The serum albumin level was significantly reduced at 24 h and remained low for a further 2 weeks. There was no histological abnormality in the liver following hepatic artery ligation. It would appear that there is an early return to normal function following hepatic artery ligation.

Animals↗
PubMed1985

Effect of beta-blockers on psychomotor performance in normal volunteers.

The effects of beta-adrenergic receptor antagonists on psychometric tests including vehicle handling, choice reaction time, and kinetic visual acuity (KVA), are reviewed. The beta-blockers had little effect on the performance tests, with the unexplained but reproducible effect of enhanced KVA performance with atenolol. Although the beta-blockers had little effect on performance tests they were shown to have psychotropic effects in normal volunteers. The reasons for the conflicting evidence concerning the effect of these drugs on performance tests is discussed in relation to the present experiments and to variables that may influence response. It is concluded that one should use tests that are as independent as possible from potentially confounding variables. The use of evoked potentials in the electroencephalogram is one such test. A preliminary study is described in which the effects of beta-blockers were detected using visual evoked responses on the electroencephalogram.

Adolescent↗