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Biomedical subjects

R E Mitchell

Publications and source records attributed to R E Mitchell.

At least 55 records · Page 3Linked to original sources
PubMed1983

The question of stress among first-year medical students.

In a study reported in this article, the authors investigated the presence of stress in two successive classes of first-year medical students at a private midwestern medical school. Support groups, didactic sessions, and no-contact control conditions were used. Few differences in personality measures were found among the groups, and all group means were within the normal range. Support groups did not facilitate academic performance. The results bring into question the previously reported extent of chronic stress among students in the first year of medical school as well as the need for support groups in this population.

Anxiety↗
PubMed1983

Effects of a low cholesterol eating plan on plasma lipids: results of a three-year community study.

In an attempt to demonstrate whether individuals with average plasma lipids would accept a diet low in saturated fat and cholesterol, members of a community organization were taught the HELP Your Heart Eating Plan. Results of 282 individuals suggest that reduced dietary cholesterol from selected foods could be sustained for up to 36 months. While both plasma cholesterol and triglycerides fell during a year of instruction, both rose to above initial values by 36 months. Overall, the results suggest that adults may be willing to accept a new style of eating temporarily but are not committed to making permanent dietary changes.

Cholesterol↗
PubMed1982

Social networks and psychiatric clients: the personal and environmental context.

The study examines the extent to which characteristics of psychiatric clients (interpersonal problem-solving) and their families (family climate and family social resources) are associated with dimensions of clients' social networks (size and support). Respondents were 35 clients recruited from outpatient psychiatric clinics and the family members with whom they resided. The results revealed that individual and environmental variables were significant correlates of social network dimensions. For example, client problem-solving was positively related to the number of intimates cited by the client, while level of independence was positively related to the degree of support clients reported receiving from their peers. Level of client psychopathology partially moderated the effects of some of the predictor variables. The results highlight the need to examine the individual and environmental processes that shape and are shaped by social network patterns.

Adaptation, Psychological↗
PubMed1982

Enhancement of individual and community competence: the older adult as community worker.

This paper presents an evaluation of a primary prevention program designed to enhance individual and community competence in older adult community workers and in community residents with whom they worked. A total of 22 community workers and 97 community residents participated in the study; 30 residents constituted as posttest-only control group. Pre-post changes included increased knowledge of community services among all participants, as well as increased number of community information channels and increased life satisfaction for the workers. Residents, particularly black residents, became more internal, and their increased sense of personal control was related to their increased knowledge of services. Thus, the helper-therapy principle was supported for these older adult, mostly female, community workers, and their helping role had a net empowering effect.

Aged↗
PubMed1981

Long-term follow-up of lung volume measurements in initially healthy young aviators.

Lung volume measurements on a large number of initially healthy young military aviators (the U.S. Navy's "1000 Aviator" cohort) were recorded periodically in follow-up from 1940-69. Vital capacities were measured spirometrically and total lung capacities were measured planimetrically from chest roentgenograms. Residual volumes were calculated by subtracting the vital capacity from the total lung capacity in each subject. Additional variables available for analysis were cigarette smoking histories, family histories, aviation career patterns, pulmonary symptoms, cardiac disease diagnoses, and anthropometric measurements. Multiple linear regression techniques were used on these variables to construct prediction equations for each lung volume in 1969. From these longitudinal analyses, cigarette smoking and pulmonary symptoms were found to be associated with an "obstructive lung volume pattern in 1969, while coronary artery disease and weight gain were found to be associated with a "restrictive" lung volume pattern in 1969. A career in military aviation had no significant association with lung volumes.

Adult↗
PubMed1981

Eight-year follow-up of exercise electrocardiograms in healthy, middle-aged aviators.

To study to prognostic capabilities of the exercise electrocardiogram (ECG) in a fit, healthy, middle-aged population, 548 members of the U.S. Navy's "1000 Aviator" cohort were exercised to 85% predicted maximum heart rate in 1969 and then followed-up in 1977 for the development of clinically evident coronary artery disease (CAD). Of these subjects, 23 (4.2%) had significant ST depression during their exercise test in 1969. At the end of the 8-year follow-up period, 38 of the 548 subjects (6.9%) had developed clinically evident CAD. The sensitivity (percent of disease predicted by an abnormal test) and predictive value (percent of abnormal tests predictive of disease) of an abnormal exercise test were 15.7% and 26%, respectively. We conclude that even in a carefully screened aviator population with a low risk for CAD, a single normal exercise ECG does not exclude the presence of latent CAD. Furthermore, in this population, a single abnormal exercise ECG should not be a disqualifying defect without further work-up.

Adult↗
PubMed1980

Relation of diet to high-density-lipoprotein cholesterol in middle-aged marathon runners, joggers, and inactive men.

We investigated the effect of diet on high-density-lipoprotein (HDL) cholesterol in 59 healthy middle-aged marathon runners, 85 joggers, and 74 inactive men. Marathon runners and joggers reported eating less red meat (P less than 0.0001), bacon (P less than 0.05), and sausage (P less than 0.01) than did the inactive men, although meat consumption was not significantly correlated with HDL. Results suggest that HDL differences (marathon runners, 65 mg per deciliter; joggers, 58 mg per deciliter; inactive men, 43 mg per deciliter) among the three groups were primarily the result of distance run, not dietary factors. Distance run was also the best predictor of the HDL:total cholesterol ratio and of total cholesterol (a negative correlation), and it was second only to weight in predicting triglyceride levels.

Adult↗
PubMed1980

Task force report: social networks as mediators of social support: an analysis of the effects and determinants of social networks.

The intent of this paper is to present a representative, though not exhaustive, overview of the current literature on social networks, with an emphasis on research linking social networks to psychological adaptation. This overview includes a review of social network concepts; and analysis of the multiple determinants of social networks; an analysis of the varied effects of social networks; and the implications for policies and practices of community mental health centers. This paper adopts the view that the concept of social network is a useful tool in examining both the functional and the dysfunctional influences of one's primary group on individual adaption.

Adaptation, Psychological↗
PubMed1979

The prognosis of breast cancer based on histological assessment.

Histopathology data from 298 patients with breast cancer have been stored in a computer, and features influencing survival have been analysed by the life table method and presented in survival curves. Prognostic features assessed were the size, type, and grade of neoplasm, the amount of stromal elastosis and lymphocytic infiltrate, and the presence and number of axillary metastases. The most reliable indications of short survival are the presence of axillary metastases and a high tumour grade. These two features are correlated, as high-grade tumours are much more likely to have metastases at presentation. No statistical difference is found in the survival of patients with metastases in one or two axillary nodes compared with those with larger numbers involved. There are differences in survival in different types of carcinoma; the well-differentiated infiltrating duct carcinoma with tubular pattern has the best prognosis, followed by the medullary carcinoma. The size of the tumour has some prognostic significance, but this is outweighed by its grade.

Adenocarcinoma↗
PubMed1978

Longevity in military pilots: 37-year followup of the Navy's "1000 aviators".

The 37-year nonmilitary mortality rate for initially healthy aviators was determined in a followup program on the U.S. Navy's "1000 Aviator" cohort. Of the 800 survivors of World War II and the Korean conflict, 95 were found to have died from nonmilitary causes over this followup period. This is markedly less than the 208 that would be expected from a random sample of white American men over a similar period (p less than 0.005). It is also significantly less than the 143 that would have been expected from a group of men who had passed an initial insurance physical (p less than 0.005). Lower-than-expected death rates occurred in all three major categories of cause of death in this age group: cardiovascular, neoplastic, and accidental. The generally good socioeconomic background, the positive genetic influence of long-lived parents, the above average intelligence, and the health and fitness orientation of the military aviator are all thought to be factors contributing to this increased longevity.

Accidents↗
PubMed1977

Number of epidermal melanocytes, hair follicles, and sweat ducts in skin of Solomon Islanders.

The number of epidermal appendages and melanocytes in forearm skin of three groups of Solomon Islanders has been determined. There were no significant differences in the number of hair follicles or sweat ducts among Solomon Islander groups, nor between them and a Caucasian group used for comparison. The Nasioi and Kwaio, however, do have a significantly higher melanocyte population than Caucasian groups. This difference may in part be due to the exposure of the Solomon Islander skin used in this study to chronic solar radiation.

Epidermal Cells↗
PubMed1977

Involvement of phaseolotoxin in halo blight of beans: transport and conversion to functional toxin.

Phaseolotoxin ([N(delta)-phosphosulfamyl]ornithylalanylhomoarginine) is produced by Pseudomonas phaseolicola (Burkh.) Dows. in liquid culture. When phaseolotoxin was applied to leaves of bean (Phaseolus vulgaris L.) at 0.1 to 1 nmoles/g fresh weight of leaf by a prick-assay procedure, the characteristic "halo" symptom of bean halo blight disease developed after 24 to 48 hours. At higher concentrations (10-100 nmoles/g fresh weight) the systemic symptoms, which are commonly a feature of diseased plants, also developed after 24 to 48 hours.When applied to bean leaves, phaseolotoxin was rapidly broken down by the sequential removal of homoarginine and alanine. N(delta)-Phosphosulfamylornithine was the major product formed, although phosphosulfamate and unreacted phaseolotoxin were also present. When P. phaseolicola infected bean plants, very little phaseolotoxin was detected within the plant, but the amount of N(delta)-phosphosulfamylornithine formed was sufficient to account for the observed chlorosis, the ornithine accumulation, and the systemic symptoms. N(delta)-Phosphosulfamylornithine therefore seemed to be the main functional phytotoxin of bean halo blight disease.When (35)S-phaseolotoxin was applied to primary leaves, (35)S (assumed to be a mixture of phaseolotoxin, N(delta)-phosphosulfamylornithine, and phosphosulfamate) was actively loaded into the fine veins of the leaf and moved through the plant in the vascular system at a speed greater than 3 cm/hour, particularly toward the apical and lateral buds and the root tips. Certain factors which affect pholem transport (arsenate, cold) affected toxin movement and the expression of systemic symptoms. Autoradiography suggested that the (35)S was transported in the phloem.A model for the involvement of phaseolotoxin in halo blight disease is presented.

Journal Article↗