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Biomedical subjects

R J Davidson

Publications and source records attributed to R J Davidson.

At least 181 records · Page 10Linked to original sources
PubMed1979

The low mean cell volume in routine haematology.

This study establishes the prevalence and distribution of an MCV less than 80 fl by review of the Coulter indices of 7887 samples. Retrospectively, 146 patients are studied and the relationships between the low MCV, film microscopy, iron status, and clinical diagnosis assessed. Plasma ferritin measured radioisotopically in 100 patients is compared to serum iron and iron binding capacity values and some of the problems of assessing iron stores are discussed. The discriminant formulae devised to differentiate between the microcytosis of thalassaemia trait and that or iron deficiency are found to be of limited value when applied to the red cell indices of a hospital population.

Adolescent↗
PubMed1979

Red cell changes in hyperthyroidism.

The Coulter 'S' red cell profile was studied prospectively in 100 untreated non-anaemic hyperthyroid patients and followed up in 52 of them until they had become euthyroid with radio-iodine or carbimazole treatment. Serial haematological data were also obtained in 23 hyperthyroid patients during treatment with beta-adrenoreceptor blocking drug alone. The most significant finding was a low mean corpuscular volume (MCV) which was invariably present throughout the hyperthyroid state. Treatment with beta-adrenoreceptor blocking drugs did not significantly alter any of the red cell parameters. On the other hand, the MCV increased and was restored to normal with radio-iodine or carbimazole treatment although there was a lag period of about 6--8 weeks between achieving the euthyroid state and the normalisation of this red cell index. While none of the patients were aneaemic, the haemoglobin level rose significantly following effective anti-thyroid treatment. It is suggested that measurement of the MCV may have a useful role in the diagnosis of hyperthyroidism. 2 possible mechanisms leading to the observed red cell changes in hyperthyroidism are postulated.

Adolescent↗
PubMed1979

Clonal evolution of marker chromosomes in a case of myelofibrosis with myeloid metaplasia and myeloblastic transformation.

The diverse spectrum of acquired chromosome abnormalities in a female patient with myelofibrosis and myeloid metaplasia is described. A sequence of karyotypic evolution involving a ring chromosome is postulated. The terminal clinical picture was unusual in that there was obstructive renal failure from extramedullary myeloblastic transformation and infiltration of the bladder, and this was also present in other sites. Initially neutrophils showed low alkaline phosphatases activity but latterly two distinct populations in which cells had either high activity or none.

Alkaline Phosphatase↗
PubMed1978

Infectious mononucleosis and Hodgkin's disease.

A cohort of 9,454 patients with infectious mononucleosis, serologically confirmed, was followed up to determine their risk of developing lymphoproliferative diseases. A total of 1,759 patients was identified in Scotland from 1959 to 1971 and 7,695 in Sweden from 1952 to 1970. The cancer cases were identified by matching the list of patients with infectious mononucleosis against a list of patients with lymphoma, nasopharyngeal and colon carcinomas registered through 1972 in Sweden and through 1973 in Scotland. A four-fold increase in risk was found for Hodgkin's disease based on 7 cases observed against 1.8 expected. Most of the excess cases of Hodgkin's disease occurred within three years of the diagnosis of infectious moonucleosis and among females. These results are similar to those of four other cohort studies and it is concluded that a positive association exists between infectious mononucleosis and Hodgkin's disease. Several explanations of this association were evaluated. Firstly, it may be that a very small proportion of persons who are in the course of developing Hodgkin's disease are temporarily misdiagnosed as having infectious mononucleosis. Secondly, infectious mononucleosis may increase the susceptibility to a factor which causes or promotes the development of Hodgkin's disease. Thirdly, infectious mononucleosis and Hodgkin's disease may share a common aetiology. Arguments in favour of, or against, each of these explanations are presented.

Adolescent↗
PubMed1978

Patterning of cognitive and somatic processes in the self-regulation of anxiety: effects of meditation versus exercise.

Davidson and Schwartz (1) have proposed a psychobiological analysis of anxiety that emphasizes the patterning of multiple processes in the generation and self-regulation of this state. The present article specifically reviews recent research on cognitive and somatic components of anxiety. A dual component scale which separately assesses cognitive and somatic trait anxiety is described and applied to the study of the differential effects of a somatic (physical exercise) and a cognitive (meditation) relaxation procedure. A total of 77 subjects was employed; 44 regularly practiced physical exercise and 33 regularly practiced meditation for comparable periods of time. As predicted, subjects practicing physical exercise reported relatively less somatic and more cognitive anxiety than meditators. These data suggest that specific subcomponents of anxiety may be differentially associated with relaxation techniques engaging primarily cognitive versus somatic subsystems. It is proposed that relaxation consists of (1) a generalized reduction to multiple physiological systems (termed the relaxation response by Benson) and (2) a more specific pattern of changes superimposed upon this general reduction, which is elicited by the particular techniques employed. The data from this retrospective study need to be followed up by prospective studies to establish the precise mechanisms for these effects.

Adolescent↗
PubMed1978

Familial erythroleukaemia: a cytogenetic and haematological study.

Clinical and haematological details of 2 siblings with a familial myeloproliferative disorder (erythroleukaemia) are presented. Their father is presumed to have died from a similar disease. The 2 siblings showed similar but not identical chromosomal abnormalities detected initially in marrow and later in peripheral blood. Serial studies revealed the emergence of an increasingly diverse pattern of chromosomal changes coincident with the haematological and clinical progression of the disease. Other members of the family were screened for cytogenetic and haematological changes. The paternal sibship displayed an increased incidence of cancer.

Adult↗
PubMed1978

High mean red cell volume: its incidence and significance in routine haematology.

With the advent of electronic particle counters of the Coulter S type the mean cell volume (MCV) has become an integral and useful feature of the red cell profile. Abnormally high values, often of minor degree, are particularly common but their precise clinical significance may be difficult to establish. This study defines the normal range and determines the incidence and distribution of the high MCV in routine hospital practice. Two hundred consecutive adult patients with an MCV of 100 fl or more were identified from the Coulter S analysis of 6542 blood samples and the underlying cause was established in 80%. Some of the clinical and economic implications of these findings are presented and briefly discussed.

Adolescent↗
PubMed1977

Cytogenetic study of 10 cases of infectious mononucleosis.

Cytogenetic analysis of 10 cases of infectious mononucleosis has revealed increased damage in the form of chromosome breakage and aberrations typical of viral infection, but in addition a few cells were consistently found to harbour a deleted number 22, similar tsponse to the mitogen phytohaemagglutinin is suggested. This inhibitor appears to have a reversible action on the patient's own lymphocytes but no inhibitory effect on control lymphocytes.

Adolescent↗