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Biomedical subjects

R F Jones

Publications and source records attributed to R F Jones.

At least 109 records · Page 6Linked to original sources
PubMed1982

Treatment of infection in the presence of an indwelling urethral catheter.

It is unnecessary to treat laboratory-diagnosed urinary tract infection in the absence of clinical symptoms and signs in patients from whom specimens of urine have been taken from indwelling urethral catheters left in situ for more than one week. If there is clinical evidence of infection, the catheter should be removed, a new catheter inserted and a specimen taken for examination. Alternatively, a suprapubic aspirate of urine may be examined bacteriologically as a treatment guide. In the absence of symptoms or other signs of infection it is doubtful whether chemotherapy is indicated.

Catheters, Indwelling↗
PubMed1982

The accuracy of eye-gaze judgment: a signal detection approach.

Two studies are reported which tested the hypothesis that eye-gaze discriminability declines with increased interpersonal distance and that this decline produces an overestimation bias. Signal detection theory was used to provide separate indices of discriminability and bias. Discriminability declined with both increased distance and, in one study, with decreased lighting. The tendency of the subject to guess that gaze was occurring when it was not mirrored the changes in discriminability, supporting the hypothesis.

Adult↗
PubMed1981

A factor comparison of old and new MCAT scales.

The old Medical College Admission Test (MCAT) and the New MCAT were compared by factor-analyzing the scores of a sample of 1,484 examinees who had taken both test batteries during 1976-77. Three common factors were extracted and interpreted. The first, a general science-quantitative factor, linked scales from both test batteries. A second factor, labeled verbal ability, characterized primarily two scales from the old test, Verbal Ability and General Information. A third factor, interpretation skills, was common to the two skills analysis scales of a new test. Specific variance for each subtest was also estimated by comparing the variance accounted for by these factors with the systematic variance indicated by the reliability. It appears that the old Quantitative Ability subtest measured unique skills which have not been incorporated into the new battery. Also the new Biology and Physics scores seem to provide specific information on knowledge in a particular discipline in addition to general science knowledge. Discussion centers on the implications of these data for the use of New MCAT scores in admissions.

Analysis of Variance↗
PubMed1981

Pathophysiology and management of raised intracranial pressure.

The mechanism of cerebral homeostasis is reviewed, paying particular attention to the way blood-brain barrier, cerebrospinal fluid and cerebral blood flow contribute to the maintenance of normal intracranial pressure. The pathophysiology of raised intracranial pressure is outlined delineating the different types of cerebral oedema. Guidelines for the management of patients with raised intracranial pressure are presented as well as the techniques of intracranial pressure monitoring.

Animals↗
PubMed1981

Induction of endogenous mammary tumor virus expression during hormonal induction of mammary adenoacanthomas and carcinomas of BALB/c female mice.

Treatment of BALB/c female mice with pituitary isografts, under conditions that established mammary hyperplasia in an anovulatory condition, enhanced mammary tumor development with prior onset of dysplastic foci in lobular parenchyma. Tumor onset began at 8 months (mean onset time, 18 mo); the 25-month incidence was 100%. Adenoacanthomatous tumors appeared first. Adenocarcinomas appeared only after more than 14 months of continuous hormone stimulation. Dysplastic and neoplastic changes occurred while blood levels of the three major mammotropic hormones were physiologic. Murine mammary tumor virus (MuMTV) p28 was detected in all tumors tested, independent of time of tumor appearance or tumor type, although keratinizing cells in adenoacanthomatous tumors did not contribute to MuMTV antigen expression. MuMTV gp52 was detected in only a small fraction of cells in a few tumors. MuMTV RNA contents were above normal in all tumors tested. Neither MuMTV structural antigens nor RNA was induced in normal glands by the same hormone treatment that ultimately resulted in dysplasia and tumor formation and elevated levels of these viral markers in neoplasms. The MuMTV RNA in all hormone-induced tumors was readily distinguishable in base sequence from standard MuMTV RNA but indistinguishable from MuMTV RNA recovered from lactating mammary glands of BALB/c females carrying only endogenous MuMTV proviruses, suggesting that endogenous MuMTV RNA sequences were induced in hormone-induced neoplasms. RNA indistinguishable from MuMTV sequences present in hormone-induced primary tumors was also detected in multiple genomic equivalents in two independently derived hormone-induced premalignant alveolar hyperplasias. MuMTV p28 was detected, but gp52 was not. The same hormone stimulus that generated 100% tumors in normal gland greatly accelerated tumor development in premalignant hyperplasias but did not amplify MuMTV RNA or antigens in either hyperplasias or the tumors derived from them. B-type virions were not detected in these tissues, in either hypophyseal implant-stimulated or virgin hosts. Cell-free virions were not detected in culture. These data suggest that the replication of MuMTV induced in hormone-induced neoplasms is defective. Details of its expression suggest that if involved in events leading to tumors, its involvement is insufficient cause for those tumors.

Adenocarcinoma↗
PubMed1980

Changes in enzyme activity during differentiation in Chlamydomonas reinhardtii.

The patterns of alanine dehydrogenase, glutamate dehydrogenase and malate dehydrogenase activity were studied during the normal vegetative cell cycle and during the processes of gametic differentiation and dedifferentiation in synchronized cultures of Chlamydomonas reinhardtii. During all three phases of growth and differentiation the synthesis of DNA was also measured. During gametic differentiation all three enzyme levels were suppressed compared to vegetative cells although DNA and cell number were comparable. During gametic dedifferentiation no DNA synthesis occurred during the first 24 h cycle and only a doubling during the second. It was not until the third cycle that a normal 4-fold increase in DNA was observed. Cell number followed a similar pattern. Although the levels of alanine dehydrogenase and malate dehydrogenase were uniformly low during the first cycle when glutamate dehydrogenase increased 4-fold, during the second cycle the patterns of these enzymes changed markedly. The enzymes did not attain levels characteristic of vegetative cells until the third cycle.

Alanine Dehydrogenase↗
PubMed1980

A serological survey of canine parvovirus infection in New South Wales, Australia.

A serological survey was conducted to ascertain, by haemagglutination inhibition testing, the presence of antibodies to canine parvovirus in 428 dogs in New South Wales, Australia. The first positive canine serum was one collected in May 1978 and the numbers of serologically positive dogs have increased markedly over the last 18 months. Twenty cats which had been vaccinated with feline panleucopenia vaccine were tested for antibody to the canine virus. None of them had a positive titre.

Animals↗