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Biomedical subjects

G D Wilson

Publications and source records attributed to G D Wilson.

At least 145 records · Page 8Linked to original sources

Social and psychological factors in the distribution of STD in male clinic attenders. II Personality disorders, psychiatric illness, and abnormal sexual attitudes.

Using standardised questionnaires we examined the possible contributions of psychiatric illness, delinquent and other abnormal personality traits, and disturbed attitudes to sex to the risk of sexually transmitted disease (STD) infection in men attending an STD clinic. We found certain differences in personality and in attitudes between the clinic sample and control men. These differences, however, a) were not comparable with those found in groups of clinically abnormal subjects, b) were confined to homosexual and bisexual men, and c), with the possible exception of gonorrhoea, were not related to risk of STD infection.

Homosexuality↗

Social and psychological factors in the distribution of STD in male clinic attenders. III Sexual activity.

We report on the relation between various aspects of sexual activity and risk of infection with sexually transmitted disease (STD) in two groups of men attending an STD clinic. Sexual promiscuity appeared to have little effect on the distribution of most STDs, showing a strong association only with gonorrhoea. This finding was contrary to expectation but consistent with the results reported in the first two papers in this series. In contrast to promiscuity, however, sexual orientation subgroups showed a sharp difference in incidence of the major STDs. Hepatitis and syphilis occurred equally commonly among bisexual and homosexual men, but much less commonly among heterosexuals; NSU occurred more commonly among heterosexual men; and gonorrhoea, though common in all three groups, occurred most commonly in bisexual men and least commonly among heterosexuals. For certain STDs the form of intercourse may be as important a risk factor as sexual promiscuity but the precise mechanisms by which sexual orientation influences risk of STD remain undefined.

Age Factors↗

Cardiovascular responses to short-term olympic style weight-training in young men.

An experimental group (N = 9) was trained similarly to olympic weight-lifters for eight weeks. Max VO2 was determined with a Beckman MMC and a Monark Cycle ergometer. Work began at 0 watts (1st minute) and was raised to 60 watts each minute until 180 watts was reached, thereafter it was increased by 30 watts until exhaustion. Short term endurance (min) was measured as time to exhaustion. Resting HR and Resting BP (auscultation) were measured immediately before the max VO2 test. Body composition was determined by hydrostatic methods. Variables were measured at 0 (T1), at 5 weeks (T2), and at 8 weeks (T3). The max VO2 showed a significant increase (p less than or equal to 0.05) over time both l . min-1 (3.25 +/- 0.38 to 3.44 +/- 0.47) and ml . min-1 . kg-1 (39.5 +/- 4.2 to 42.4 +/- 5.5). Resting heart rate decreased from 63.9 +/- 8.9 to 58.8 +/- 6.5, systolic blood pressure decreased significantly from 119.3 +/- 13.4 to 114.8 +/- 9.0, diastolic pressure did not change (70.9 +/- 7.9 to 71.3 +/- 7.3). Lean body weight increased significantly from 64.9 +/- 7.4 to 67.3 +/- 7.7 kg, and % fat decreased significantly from 18.9 +/- 6.3 to 15.9 +/- 6.1. These data suggest that weight training can produce a significant positive change in some cardiovascular parameters.

Adult↗

Suppression by bromocriptine of the serum lactalbumin peak associated with human lactogenesis.

The endocrine environment necessary for human lactation has not yet been clearly defined. In particular the role of prolactin is uncertain, since levels of this hormone usually fall to the normal non-lactating range during the course of prolonged lactation. We have found that the immediate post-partum peak of serum lactalbumin associated with lactogenesis was abolished by treatment with bromocriptine. This suggests a direct relationship between prolactin and lactalbumin production at this time.

Bromocriptine↗

Human alpha-lactalbumin and hormonal factors in pregnancy and lactation.

Serum alpha-lactalbumin was monitored throughout pregnancy in twelve women and in a separate group of nineteen women during the first 3 months postpartum. During pregnancy alpha-lactalbumin rose significantly until the mid trimester (P less than 0.001). From then until term, concentrations remained stable. Concentrations during labour were significantly higher (P less than 0.01) than those seen at term. alpha-lactalbumin, 17 beta-oestradiol and progesterone concentrations behaved similarly during the first week of the puerperium in both lactating (n = 10) and non-lactating (n = 9) subjects. A large surge of alpha-lactalbumin closely followed the clearance of high circulating concentrations of sex steroids in both groups. Prolactin concentrations were significantly greater (P less than 0.02) in lactating subjects by the third postpartum day. By the third postpartum week alpha-lactalbumin concentrations in lactating subjects had stabilized at labour levels in a milieu of high prolactin levels and depressed production on 17 beta-oestradiol and progesterone. Conversely, in non-lactating subjects alpha-lactalbumin concentrations fell, as did prolactin, coincidental with a rise in 17 beta-oestradiol, progesterone concentrations remaining barely detectable. The apparent control mechanisms for human alpha-lactalbumin secretion and thus, lactation, are discussed in the light of the data presented.

Estradiol↗

Effect of prolactin on lactalbumin production by normal and malignant human breast tissue in organ culture.

To determine whether lactalbumin production by normal and neoplastic human mammary tissue is under the same control, the effect of prolactin treatment was studied in organ culture. Of 9 premenopausal normal breast samples, 6 produced lactalbumin in culture, and all 6 responded to prolactin treatment over 4 days. One biopsy of pregnant breast tested also responded to prolactin treatment, producing 200 times more lactalbumin in culture than did normal breast. Two of 4 normal postmenopausal biopsies produced lactalbumin, and one increased synthesis and release after prolonged exposure to prolactin. Of 10 scirrhous carcinomas, 6 produced lactalbumin, but none responded to prolactin treatment. In 2 premenopausal patients, normal breast tissue responded to different concentrations of prolactin, which were without effect on malignant tissue from the same breast. In summary, lactalbumin production in the samples that we have studied can be stimulated in normal but not in malignant breast tissue. This may indicate an absence or deficiency of prolactin receptors in malignant tissue.

Breast↗

Effects of varying concentrations of N2/O2 and He/O2 on exercise tolerance in man.

Hyperoxic gas mixtures improve exercise tolerance in humans. It is not clear whether this improvement is due to 1) a decreased anaerobiosis in the working cell, 2) a decreased cost of breathing resulting from the relative hypoventilation in hyperoxia, 3) the reduction of a possible metabolic depressant-N2, or a combination of these. This study made use of He/O2 breathing mixtures to gather data relative to #2 and #3, primarily. Ten subjects ran to exhaustion on a treadmill breathing one of four mixtures-20 O2/80 N2, 20 O2/80 He, 80 O2/20 N2, 80 O2/20 He. Running time to exhaustion, minute ventilation, respiratory frequency, tidal volume, and heart rate were measured. Performance increased significantly on hyperoxic mixtures (P < .001) and He/O2 mixtures (P < .001). Although the peak ventilatory volumes were higher on He/O2 mixtures, the ventilatory mass moved was significantly less (P < .001) on those mixtures conceivably resulting in a decreased cost of breathing. These data did not reject any of the hypotheses but offered the greatest support for hypothesis #2.

Adult↗

Typewriting rate as a function of reaction time.

This study was designed to determine the relationship between reaction time and typewriting rate. Subjects were 24 typists ranging in age from 19 to 39 yr. Reaction times (.001 sec) to a light were recorded for each finger and to each alphabetic character and three punctuation marks. Analysis of variance yielded significant differences in reaction time among subjects and fingers. Correlation between typewriting rate and average reaction time to the alphabetic characters and three punctuation marks was --.75. Correlation between typewriting rate and the difference between the reaction time of the hands was --.42. Factors influencing typewriting rate may include reaction time of the fingers, difference between the reaction time of the hands, and reaction time to individual keys on the typewriter. Implications exist for instructional methodology and further research.

Adult↗

Fetal and maternal mineral concentrations in dairy cattle during late pregnancy.

Concentrations of ionic and total calcium, magnesium, and inorganic phosphorus in plasma were determined in bovine fetuses and their mothers within the last month before delivery. Mean fetal concentrations were higher than corresponding maternal contents during the 22 days before delivery. Ionic and total calcium in plasma fell towards term in mother and fetus. Fetal phosphorus was elevated before parturition while maternal phosphorus fell. Maternal magnesium was elevated slightly at parturition.

Animals↗

Fetal and maternal plasma electrolytes, blood gases, and pH in dairy cows during late gestation.

Sodium, potassium, and chloride were determined in fetal and maternal plasma of six cows between 208 and 269 days of gestation. Blood pH and partial pressures of oxygen and carbon dioxide also were measured in samples collected from the jugular vein of the cow and the caudal aorta and vena cava of the fetus. Concentration of chloride in fetal plasma was generally lower than the corresponding maternal value, and fetal potassium was greater than maternal. Potassium of fetal plasma increased towards term. Sodium concentrations were not significantly different between fetal and maternal plasms. Once fetal and maternal pH and blood gas tensions had stabilized after surgery, there was little change until shortly before delivery. In the last 24 h before calving maternal partial pressure of oxygen was high and fetal blood pH was low.

Animals↗

Determination of continuing medical education needs of clinicians from a literature search study, Part I. The study.

Continuing medical education is an area of current concern to health sciences librarians. A comprehensive study of literature searches requested by physicians and by fourth-year medical students serving their five-week preceptorship with a rural physician was conducted: (1) to determine if there is any pattern to the requests received so that areas of study for continuing medical education can be ascertained; and (2) to determine whether there is any appreciable difference in nature and complexity between those searches requested by clinicians and those requested by medical student preceptees. Literature search requests were examined in terms of individual MeSH subjects, subcategories, and categories for each subject covered in every search. This analysis has demonstrated that assessing the clinical problems of practicing physicians may be one method of determining needed continuing medical education topics.

Bibliographies as Topic↗

Effects of hyperoxic gas mixtures on exercise tolerance in man.

This study was undertaken to determine the effects of O2-enriched gases on performance. Nine trained subjects ran to exhaustion on the treadmill on five different occasions breathing one of a range of hyperoxic gas mixtures--20%, 40%, 60%, 80%, or 100% O2. Each subject worked at a workload determined to be 110% of that necessary to elicit his maximum O2 uptake. The exercise bouts were scheduled one week apart to minimize the effects of training and fatigue. The subjects were given no cues as to the mixtures being breathed or to their running times. The parameters measured included running time, minute ventilation, and heart rate. The results indicate that the maximum performance time increases significantly as the O2 fraction of the gas is increased. Contrary to other published literature, 100% O2 increases performance significantly over 60% O2. Ventilation at any point in time is decreased when breathing hyperoxic mixtures. This decrease appears to be more a function of breathing frequency than of tidal volume. Terminal heart rates are not significantly different regardless of the O2 fraction of the inspired gas.

Adult↗