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121.
Adult respiratory distress syndrome (ARDS) is a clinical syndrome which occurs due to various direct or indirect noxious agents and pyhsical mechanisms. One of the etiological factors is ingested chemicals (e.g. paraquat, ethylene glycol). The organophosphorous (OP) insecticides are the most toxic and frequently encountered chemicals that produce poisoning in humans. Studies were undertaken to investigate whether OP insecticides may produce ARDS. Fifteen autopsy cases due to suicidal OP insecticide poisoning were investigated. Toxicological analyses were performed with a gas chromatography-nitrogen phosphorous detector (GC-NPD). Methamidophos, dimefox and dichlorvos were the detected OP. Lungs were examined macroscopically. Two cases showed features compatible with ARDS in which the only cause of death was OP poisoning. Due to the severity of ARDS it is important to assess insecticidal exposure in an attempt to enhance survival patterns following OP poisoning in patients in order to initiate therapy. 相似文献
122.
Keith M. White Jerome J. Congleton Olga J. Pendleton R. Dale Huchingson Rodger J. Koppa 《International journal of occupational safety and ergonomics》2013,19(4):315-335
This research used distal motor latency (DML) and vibration thresholds (VT) to evaluate 84 hand activity and wrist deviation combinations to determine the best association with carpal tunnel syndrome (CTS). Female volunteers, 2 healthy and 2 CTS diagnosed, were age matched and operated a keyboard for 4 hrs a day. Room temperature was 28°C(±2). Beginning DML and VT were taken with a relaxed neutral posture hand. The wrist was deviated in a randomly selected combination, and determinations were taken at 5-min intervals. The trial ended at 20 min or when discomfort was felt. The CTS conditions were discriminated by pain four times, DML once, and VT 14 times. Vibrometry was the most consistent CTS discriminator. The best VT results for wrist positions were obtained with wrist extension and extended extension, whereas the unclenched, clenched, and loaded power grip activities proved to be the most consistent hand activities. 相似文献
123.
Within populations of many species, individuals that are otherwise similar to one another in age, size or sex can differ markedly
in behaviours such as resource use, risk taking and competitive ability. There has been much research into the implications
of such variation for intraspecific interactions, yet little investigation into its role in influencing interspecific interactions
outside of a predator–prey context. In this study, we investigated the role of individual-level behavioural variation in determining
the outcomes of interactions between two ecologically similar fishes, the threespine and ninespine sticklebacks (Gasterosteus aculeatus and Pungitius pungitius). Experiment 1 asked whether individuals of both species were consistent in their expression of two behaviours: activity
in novel surroundings and latency to attack prey. For each behaviour, focal individuals were assayed twice, 10 days apart.
Performances were positively correlated between exposures, suggesting behavioural consistency within individuals, at least
over this timescale. Experiment 2 revealed not only differences in habitat use described both by species-level variation,
with ninespines spending more time in vegetated areas, but also by individual differences, with more active individuals of
both species spending more time in open water than in vegetation. Experiment 3 revealed that when heterospecific pairs competed
for prey, bolder individuals consumed a greater share, irrespective of species. These findings suggest that individual-level
variation can facilitate overlap in habitat use between heterospecifics and also determine the outcomes of resource contests
when they meet. We discuss how this might vary between populations as a function of prevailing selection pressures and suggest
approaches for testing our predictions. 相似文献
124.
We performed male attraction experiments and staged courtship sequences to test for non-random mating with respect to social
behavioral phenotype in the comb-footed spider, Anelosimus studiosus. While asocial behavior is the dominant phenotype in all A. studiosus populations examined to date, a social phenotype approaches a frequency of 15% in colder environments. We collected test
subjects from higher latitude polymorphic populations and scored all individuals as to their behavioral phenotype prior to
their use in these trials. Males of both phenotypes differentially approached and courted social females over asocial females
and no-spider controls. By offering males different numbers of females of one type vs. the other in subsequent trials, we
determined that the difference in attractiveness between the two phenotypes social/asocial is 1.5/1. Both the web produced
by a female and a female that has been removed from its web attract males. We suggest that the male attracting pheromone is
present on females and is also attached to silk threads. Staged encounters completed between males and females of the respective
phenotypes demonstrated that courting males suffer significantly less pre-copulatory sexual cannibalism with social females
than with asocial ones, and thus, female social tendency is phenotypically linked to sexual aggression. We propose that the
male preference for social females is adaptive because of the observed asymmetry in courtship success. 相似文献
125.
通过改变声波的频率、声压等参数,观察了单独反吹清灰和声波辅助反吹清灰的试验结果。试验证明,声波能有效地降低滤袋的残余阻力和残留粉尘重量。 相似文献
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129.
Dr. Jane L. Halliday Lyndsey F. Watson Judith Lumley David M. Danks Leslie J. Sheffield 《黑龙江环境通报》1995,15(5):455-465
Current measures of livebirth prevalence of Down syndrome are derived from data obtained up to 20 years ago, before the introduction of the prenatal diagnostic tests amniocentesis and chorionic villus sampling (CVS). For women aged 36–52 years, but who were not tested prenatally, we proposed to make a direct estimate of current livebirth prevalence of Down syndrome. We could also determine prevalence at the time of CVS and amniocentesis in women of the same age undergoing prenatal testing. Differences in these prevalences allow an estimation of the relative loss of Down syndrome during pregnancy. In Victoria, Australia, we identified 3041 women having CVS, 7504 having amniocentesis, and 13 139 having no test. Smoothed regression estimates of age-specific livebirth prevalence were found to be higher than in the early studies. The estimate of spontaneous loss was 17 per cent between the time of CVS and amniocentesis, and 18 per cent after the time of amniocentesis. The latter figure is lower than previous estimates and may be explained by a greater likelihood of a Down syndrome fetus surviving to be liveborn, given the modern approach to early obstetric intervention. These current risk estimates of livebirth may be useful updates for genetic counselling, but perhaps more importantly, may be used as precise maternal age-related risk figures, necessary in the design and implementation of prenatal screening programmes for Down syndrome. 相似文献
130.
Fears R 《Disasters》1985,9(2):134-138
In 1981 in Madrid, a new disease was identified, and attributed to the fraudulent sale of adulterated, industrial-quality oil as olive oil. The competing hypotheses for the clinical symptoms and tissue changes are reviewed but it is also important to note the general similarities between this epidemic and those other incidents where food adulteration has presented an acute hazard. 相似文献