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Biomedical subjects

J Harrison

Publications and source records attributed to J Harrison.

At least 235 records · Page 13Linked to original sources
PubMed1982

Auditory brainstem responses in the aged cat.

Auditory brainstem responses (ABRs) were compared in young adult and aged cats. Mean thresholds for click-evoked ABRs were greater in the aged cats. Clicks normalized to 15 and 30 dB above individual thresholds at rates of 10, 20, 50 and 100/sec evoked ABRs with similar latencies and central conduction times in both groups. Background noise at equal intensity for all cats completely suppressed ABRs evoked by clicks 30 dB above threshold in 2/3 of the young but none of the old cats. As rise time of a 25 msec noise burst at equal intensity for all cats increased 1, 2, 5, and 10 msec, latency of wave 4 increased more for the old cats than for the young. Summed monaural ABRs from both ears were greater than binaural ABRs for waves 4 and 5 in both groups. These data indicate peripheral auditory dysfunction in aged cats but little abnormality in auditory brainstem transmission with click intensity normalized for ABR threshold.

Aging↗
PubMed1982

Serum enzyme changes during chemotherapy for ovarian cancer.

Serum lactate dehydrogenase (LD), gamma-glutamyl transferase (gamma GT) and alkaline phosphatase (ALP) activities have been measured in 105 patients with ovarian cancer for periods of up to 4 years. The extent of the disease was assessed at laporotomy according to the FIGO classification. Chemotherapy was started one week after surgery, at which time 25% of patients had elevated LD, 29% elevated gamma GT and 21% elevated ALP. Of 51 patients who went into complete remission, 4% still showed elevated LD, 25% elevated gamma GT and 12% elevated ALP. Reactivation of tumour growth was apparent in 32 patients; there was a significant increase in the serum LD, gamma GT and ALP activities when remission and recurrence were first detected in 65%, 50% and 35% of patients respectively. With 14 patients, there was an unexplained increase in the activity of one or more of the enzymes 1-6 months prior to recurrence being detected; these changes may predict that chemotherapy is losing effect. During long-term remission, serum LD was increased in patients suffering from urinary tract infection or bladder dysfunction.

Alkaline Phosphatase↗
PubMed1982

Subtalar arthrodesis for adult traumatic arthritis.

In this study the effectiveness of the modified Grice extra-articular subtalar fusion in treatment of painful subtalar arthritis postintra-articular os calcis fractures was evaluated. Twenty-one patients with 23 Grice fusions returned for questioning, clinical assessment and roentgenography. There were 16 males and 5 females. The ages ranged from 20 to 69 years (average 43.3 years). The follow-up period ranged from 2 to 9 years (average 4.3 years). The back-to-work time ranged from 2 weeks to 2 years (average 6.2 months). The patients were questioned and examined according to a described rating system. The patients and surgeons rated 10 of 23 (43.5%) fusions good, 12 to 23 (52.2%) satisfactory, and 1 to 23 (4.4%) fusions unsatisfactory. Eighteen patients (85.7% were fully active, and 3 patients (13.3%) changed to lighter work or activities. All fusions were solid clinically and radiologically. Complications were few and included three mildly painful iliac crest graft donor site scars, one superficial wound infection which resolved quickly, and one foot neuroma. In summary, the modified Grice extra-articular subtalar fusion is simple, reliable, and effective in the treatment of painful traumatic subtalar arthritis.

Adult↗
PubMed1982

Humoral and cellular immune responses of rabbits to sub-viral fractions of human cytomegalovirus.

We have raised specific sera against human CMV (strain AD 169) and have tested the immunogenicity of viral envelopes, removed using the non-ionic surfactant Triton X-100. Glycine-buffered extracts of infected MRC-5 cells elicited virus-neutralizing antibody to a titre of 1/1600. Incubation of this material also elicited a considerable reaction against host cell antigens. Inoculation of viral envelope material in Freund's complete adjuvant also elicited virus-neutralizing antibodies. Specific in vitro transformation of peripheral blood lymphocytes taken from inoculated rabbits was not always demonstrable, but could be achieved with blood taken from one rabbit up to one year after the initial inoculation of envelope material.

Animals↗
PubMed1981

Epidermal growth factors enhances viral transformation of granulosa cells.

Kirsten sarcoma virus produced a low incidence of transient morphological transformation in primary cultures of rat ovarian granulosa cells. In the presence of epidermal growth factor, the incidence of transient transformation increased severalfold and two continuous cell lines were established. Epidermal growth factor, a naturally occurring polypeptide hormone, appears to act here as a tumor promoter in the retrovirus-induced transformation of a mesodermally derived epithelium.

Animals↗
PubMed1981

Propranolol in experimentally induced stress.

The influence of beta-adrenoceptor antagonism on the effects of a single experimental stress was investigated in 12 healthy volunteers, using a double-blind protocol. A single oral dose of 80 mg propranolol reduced the stress-induced increase in heart rate and systolic blood pressure to 49.9 per cent and 8.3 per cent respectively compared to 61.0 per cent and 17.4 per cent with placebo. The rise in diastolic blood pressure was small and unaffected by beta-adrenoceptor blockade. The rise in temperature of the skin of the trunk was significantly reduced by propranolol. The self-rating of anxiety, alertness and concentration by the subjects was unaffected by propranolol.

Adult↗
PubMed1980

The course of untreated Plasmodium inui infections in the rhesus monkey (Macaca mulatta).

This report deals with the major features of untreated infections with Plasmodium inui as exhibited in a group of 31 rhesus monkeys (27 inoculated with trophozoites, four with sporozoites). Infections in nine monkeys were followed to self-cure. In 22 subjects they were interrupted prematurely; in 17 by chemotherapy 454 to 3,931 days after onset of patency; in 5 by death 491 to 1,025 days after onset of patency. Substantial monkey-to-monkey variations were encountered in the intensity of the parasitemia and its cyclic undulations, in the morbid features of the disease, and in the duration of infection. Thus initial peak parasitemias varied by as much as 15-fold. Some post-peak parasitemias were sustained at relatively constant and moderately high levels for many months; others fluctuated cyclically between barely detectable and readily countable numbers. In most subjects, there was no evidence of morbidity attributable to malarial infection; in two, reactions were severe enough to lead to death. The duration of untreated infections could be as brief as 14 months or could approach 14 years. With due allowance for premature interruptions, the majority of infections could be expected to persist for 4--6 years.

Animals↗
PubMed1980

Serial studies in von Willebrand's disease: variability versus "variants".

The variability of laboratory findings in von Willebrand's disease (vWd) was evaluated by performing serial studies of bleeding time (BT), factor VIII coagulant activity (VIII:C), factor-VIII-related antigen (VIIIR:Ag) and ristocetin cofactor (VIIIR:Rcof) in 50 individuals from 25 families with this disorder. The types of results were characterized from 1 to 16 based on the possible combinations of findings using these four tests. The only patients observed to have consistently abnormal results of all four tests were three individuals with homozygous vWd. Individuals with autosomal dominant vWd were found to have a variety of results and all 16 possible types were observed. Although a consistent pattern was present within some families, others with equivalent history of bleeding demonstrated widely variable types of results. The results within some families, others with equivalent history of bleeding demonstrated widely variable types of results. The results of serial studies of the same tests in 10 normal individuals indicated relative stability, with nearly all values within the usual range of normal, but some independent variation of factor-VIII-related activities was observed. These studies indicate that: (1) the results of BT, VIII:C, VIIIR:Ag, and VIIIR:Rcof vary considerably from time to time in many individuals with vWd, (2) a classification of "variants" of vWd based solely on such studies may be inappropriate, particularly if the tests are not repeated, and (3) repeated testing may be required to establish the diagnosis of vWd in some individuals.

Bleeding Time↗
PubMed1979

The effect of high dose oxprenolol on stress-induced physical and psychophysiological variables.

The effects of oral oxprenolol (480 mg) and lorazepam (2 mg) on skin conductance, reaction time, critical flicker frequency and self-rating visual analogue scales for anxiety, sedation and concentration were investigated in 6 healthy male volunteers. Oxprenolol exerted a central action similar to lorazepam as shown by a significant lowering of skin conductance and decrease in the number of spontaneous fluctuations during stress, impaired critical flicker frequency and decrease in alertness with reduced concentration.

Adolescent↗