Search PubMed⌕ Search

Biomedical subjects

J H Pearn

Publications and source records attributed to J H Pearn.

16 recordsLinked to original sources
PubMed1992

Courage and curiosity: surgeon-explorers in Australia and New Zealand. Part II. The science of the outback. The Herbert Moran Lecture concluded.

After the broad brush of the topographical features of Australia and New Zealand had been mapped, the process of fine-tuning the geographic details of these countries continued. In parallel with this, a great wave of detailed scientific exploration proceeded and it was to these expeditions that medical men brought special skills. Surgeons played a special role because of the need of their practical skills in the field. Dozens of expeditions were commissioned throughout the nineteenth century. The aim of some was to search for minerals and document the fertility and water supply for pastoral and agricultural lands. Others had as their major raison d'etre the documentation of the many groups of animals and plants which populated these domains new to Western science. Surgeons and physicians were valued not only for their professional skills in the field, but for the pursuit of botany, zoology and geology, and in many cases for ethnological studies as well.

Anthropology↗
PubMed1979

Swimming ability of children: a survey of 4000 Queensland children in a high drowning region.

The swimming ability of 4128 Queensland school children was studied. The median age for swimming 10 metres is 6.5 years. Ninety-five percent of children are able to swim by 11 years of age. Cumulative frequency curves, by age, are presented for the ability to swim 10 and 50 metres: the latter distance is of relevance in boating accidents. Twenty percent fewer children from lower socioeconomic levels are able to swim. Water safety training is as important as swimming lessons.

Adolescent↗
PubMed1979

Survival in subzero temperatures: two field experiments on temperature estimation and "snowhole" (survival hole) temperatures.

Two field experiments in a subarctic environment are described. Individuals consistently underestimated the degree of cold, because visual cues dominated sensory skin receptors in the subjective estimation of temperature. In snowholes (survival holes) temperatures rose 20 degrees C within 30 minutes of occupancy, but stabilized at freezing point. Implications for travel and survival in a subzero environment are described.

Cold Climate↗
PubMed1979

Sequential intellectual recovery after near-drowning.

Sequential neurological and intellectual recovery after childhood near-drowning is discussed. Decisions concerning the persistence and intensity of resuscitation require a knowledge of the natural history of intellectual improvement after rescue from near-drowning. A severe case of fresh-water immersion, leading to recovery, is described. Evidence is presented to suggest that the time interval of one hour before the first spontaneous respiratory gasp forms the upper limit of the apnoeic time bracket after which survival can still be expected, and to indicate that intellectual improvement (to a measured IQ of 97) can occur even after initial decerebrate signs if vigorous therapy is prosecuted. The proportion of cases capable of sequential neurological improvement is unknown. A time base for sequential clinical and intellectual improvement after near-drowning is presented to form a yardstick with which future cases may be compared.

Brain Damage, Chronic↗
PubMed1979

Drowning and near-drowning involving children: a five-year total population study from the City and County of Honolulu.

A study of all serious childhood immersion accidents (both drowned and near-drowned cases) is reported from Hawaii. This is a total population-based survey of 140 consecutive cases (0--15 years) occurring during the five-year period (1973--1977. Age-specific, sex-specific, and osmolality-specific (salt versus fresh water) data are presented both for survivors and fatalities. The overall annual drowning rate of 3.1 per 100,000 children at risk is low, for a water-oriented society. The survival rate following loss of consciousness in the water is 73 per cent. There is no evidence from this study that osmolality affected the probability of survival. The rank order of importance of drowning sites is swimming pools, surf, sheltered salt water bathing, domestic bath tubs, fresh water streams, salt water canals, and garden fish ponds. Specific accident rates, by sex, outcome, and site of immersion are also presented. No secular trend in the rate of drowning was observed in this study. Comparison with the only other available total population survey (Australia) of childhood immersions reveals common epidemiological and demographic patterns in modern urban societies and suggests that safety regulations play a role in reducing swimming accidents and fatalities in children.

Adolescent↗
PubMed1979

Bathtub drownings: report of seven cases.

The domestic bathtub is an important site for infant drownings. A total population study of drowning and near-drowning accidents involving Honolulu infants has enabled the risks to be specified with greater detail. A series of seven consecutive bathtub immersion accidents is presented. The "at risk" profile comprises highly mobile families of lower socioeconomic status; usually younger siblings in larger families are involved and often the father had immediate care of the infant at the time of the accident. Another case of bathtub immersion as a form of nonaccidental injury is described. In five of the other six cases reported, the drowned child was left attended by an older sibling. Preventive strategies are discussed.

Accidents, Home↗
PubMed1978

A clinical study of chronic childhood spinal muscular atrophy. A review of 141 cases.

The case histories and clinical details of 141 children (67 males and 74 females) with chronic childhood spinal muscular atrophy (SMA) have been reviewed. Hundred of these children were alive at the time of the study. The cases comprise a consecutive unselected series of all with this disease who presented to two large English neurological centres over a 10-year tracing period. Chronic childhood SMA is defined here as a progressive disease of anterior horn cells with initial proximal selectivity, which does not of itself cause death before 18 months of age. Clinical signs are first manifest between birth and 8 years of age, but in 95% before 3 years. Cumulative frequency tables for motor skills are presented; 46% of children never walked, even with orthopaedic aids; 37.6% were able to walk unaided at some stage. No child was able to run after 12 years of age. Late-presenting sporadic cases retain motor skills longer than do familial cases. A sex influence on the clinical course of the disease has been demonstrated, males being more severely affected. Cumulative frequency curves for age-at-onset and age-at-presentation have been compiled. A sib of an affected index case, still clinically normal at 2 years of age, has passed 90 percent of his risk period; the use of such cumulative frequency curves for studies of carrier-frequency and incidence is discussed. The median age at death for this disease exceeds 10 years. The range encompassed by the clinical spectrum is discussed.

Adolescent↗
PubMed1978

A clinical and genetic study of spinal muscular atrophy of adult onset: the autosomal recessive form as a discrete disease entity.

A clinical and genetic study of spinal muscular atrophy (SMA) of adult onset is reported. A genetic analysis of all cases of SMA occurring over a ten-year period in North-east England (48 index cases) has shown that chronic proximal SMA of adult onset is a distinct clinical and genetic entity, and is not a variant of the more common and relatively benign late juvenile cases. Nine cases of SMA of adult onset have been studied, occurring in 6 families. The median age of clinical onset was 35 years and the mean age at initial medical presentation was 37 years. The sex ratio was 5:4 (males:females). The condition is relatively benign and there is no evidence to date that life expectancy is shortened; there is usually no premonitory evidence of muscular weakness in early adult life. The muscular involvement is relatively symmetrical and the distal musculature is well preserved; clinical progression of the disease is interrupted by periods of apparent arrest. No patient was able to walk completely unaided twenty years after the initial clinical onset; the median age of patients in the study was 61 years but only one was confined to a wheelchair. In the early stages the recessive form of familial motor neuron disease must be excluded. A segregation analysis of sibs born after index cases was undertaken (segregation ratio of 0.20). This finding is consistent with autosomal recessive inheritance with an extended period during which the disease might initially present. The presence of new dominant mutations cannot be excluded, but is unlikely to account for more than 10% of cases. The carrier rate in the English population is estimated to be 1 in 300, with a gene frequency q = 0.00165. Prevalence is 0.32 per 100,000 in the general population. Empirical risks for genetic counselling are presented.

Adolescent↗
PubMed1977

Swimming pool immersion accidents: an analysis from the Brisbane drowning study.

An analysis of a consecutive series of 66 swimming pool immersion accidents is presented; 74% of these occurred in in-ground swimming pools. The estimated accident rate per pool is five times greater for in-ground pools compared with above-ground pools, where pools are inadequately fenced. Backyard swimming pools account for 74% of pool acidents. Motel and caravan park pools account for 9% of childhood immersion accidents, but the survival rate (17%) is very low. Fifty per cent of pool accidents occur in the family's own backyard pool, and 13.6% in a neighbour's pool; in the latter the survival rate is still low at only 33%. In only one of the 66 cases was there an adequate safety fence; in 76% of cases there was no fence or barrier whatsoever. Tables of swimming pool accidents by age, season, site and outcome are presented.

Accidents↗