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991.
OBJECTIVE--To investigate whether fatal accidents, including drownings, have decreased among Icelandic fishermen and seamen. DESIGN--Historical prospective study. The study population was record linked with the National Register and the Register of Deceased to get information on water transport accidents (ICD-7, E850-E858) during the period 1966-86. The number of persons in each calendar year and the number of days at sea registered at the pension fund were both used as denominator to find annual mortalities. SETTING--Iceland. SUBJECTS--27,884 seamen who were members of the Seamen's Pension Fund. The cohort included both fishermen and seamen from the merchant fleet. MAIN OUTCOME MEASURES--Changes in mortality from all accidents and drownings from 1966-86. RESULTS--The mortality for all fatal accidents was 89.4 per 10(5) person-years and did not change appreciably during the study period. The mortality for drowning was unchanged at 73.2 per 10(5) person-years. The greatest number of drownings were among those 20-24 years of age but the mortality for drowning was highest among those 45-54 years of age. CONCLUSION--Mortality because of fatal accidents and drownings among these seamen was high and did not conclusively decrease during the study period. Further preventive measures are needed. 相似文献
992.
The aetiology of experimental fibrosing alveobronchiolitis induced in rats by paprika dust. 下载免费PDF全文
The effect of a single intratracheal dose of respirable paprika (Hungarian) dust, paprika dust extract, and cellulose dust on the lungs of rats was examined sequentially one and three months after a treatment. Treatment with respirable paprika and cellulose dusts resulted in alveobronchiolitis at the end of the first month and fibrotic changes at the end of the third month. As the extract of paprika dust caused no histopathological alterations, it is assumed that the high cellulose content of paprika was responsible for the histological reactions. 相似文献
993.
994.
The incidence of transient hypogammaglobulinaemia of infancy (THI) detected in a major paediatric centre over a 10 year period was examined. A total of 2468 subjects less than 2 years of age had an IgG measurement taken between July 1979 and March 1990. Subjects with known immunodeficiencies were excluded. Fifteen patients were classified as having THI with an initial IgG level less than the fifth centile followed by a second measurement within the normal range. A further 24 patients were identified as having possible THI with a single low IgG concentration. There were 60,174 live births each year in Victoria in the years 1979-88. This gives an incidence of proved THI of 23 per 10(6) births, and including proved and probable THI an incidence of 61 per 10(6) live births. Of those patients with proved THI 12/15 had symptoms of either atopic disease or food allergy/intolerance and three had gastrointestinal symptoms without any evidence of atopic disease. At presentation 12/15 (80%) were IgA deficient and 9/15 had IgM concentrations less than the 20th centile for age. It is suggested that in view of the preponderance of atopic and food intolerant patients that subclinical protein loss from the bowel due to allergic inflammation may be a contributing factor to the development of THI in some patients. 相似文献
995.
D Purves L E White 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(18):8339-8342
Faced with an unobstructed view, both foveas can be readily aligned with a distant visual target. The minor difference in the view of the two eyes (which arises from slightly different lines of sight) presents no special problem and is, indeed, the basis of stereopsis. However, when obstructing objects are present in the foreground, the view provided by one eye becomes wholly or partially incompatible with the view of the other. We have investigated how we cope with this everyday situation by having volunteers observe distant targets through a fenestrated screen. In this circumstance, subjects naturally position themselves to view a target of interest with one eye--usually the right eye. This monocular habit in normal viewing reinforces other evidence for the unorthodox idea that visual perception arises from a union in consciousness of monocular images that are elaborated independently. 相似文献
996.
997.
Oxygen-regulated control elements in the phosphoglycerate kinase 1 and lactate dehydrogenase A genes: similarities with the erythropoietin 3'' enhancer. 总被引:18,自引:5,他引:13 下载免费PDF全文
998.
999.
1000.
The health of a team participating in the 1990 World Solar Car Challenge was recorded for 10 of the 11 race days. Morbidity was collected during daily consultations with the team doctor and the diagnoses were later converted to the ICPC code. Team members' self-perceived health status was also recorded daily, using the Nottingham Health Profile. Team drivers consulted the doctor more often than the support staff and the three full-time drivers had significantly more diagnoses than the support staff. The Nottingham Health Profile scores on sleep, energy and emotional reactions showed correlations between higher minimum temperatures and sleep for all team members and for the three full-time drivers, there were significant correlations between increasing maximum temperatures and emotional reaction scores. The morbidity records and perceived health scores reflect the conditions of the race. Twenty-five per cent of full-time driver consultations dealt with skin, eyelid or finger infections probably caused by the lack of washing water. The scores on sleep and emotional reactions were affected by temperature and previous research reports degradation in concentration and dual tasks with increasing temperature. This may account for the difficulty some drivers had in continuing their shifts. Close supervision of the drivers and the recording of their perceived health status helped reduce the health problems of the team. 相似文献