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71.
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Tim Borges Howard P. Glauert Li -Chuan Chen Ching K. Chow Larry W. Robertson 《Archives of toxicology》1990,64(1):26-30
The possible interrelationships between the effects of dietary selenium and perfluorodecanoic acid (PFDA) on growth and lipid metabolism were studied in the male Sprague Dawley rat. Rats were divided into groups and placed on diets containing three levels of selenium (0.04, 0.2, and 1.0 ppm as sodium selenite). Two weeks later, half the rats in each group received a single 35 mg/kg IP injection of PFDA in corn oil, while their pair-fed companion received only vehicle. Rats injected with PFDA stopped gaining weight, and weighed less than pair-fed controls, despite equal food intakes. Two weeks following PFDA administration the rats were killed and plasma cholesterol and triglycerides, and liver peroxisomal enzyme activities were quantified. In contrast to other peroxisome proliferators, PFDA increased plasma triglycerides while decreasing plasma cholesterol. The rate of peroxisomal fatty acid -oxidation was decreased, even though the activity of fatty acyl-CoA oxidase, the first enzyme in the peroxisomal fatty acid -oxidation pathway, was increased. Dietary selenium, other than increasing the liver to body weight ratio, did not alter growth or lipid metabolism. This study demonstrates, for the first time, the existence of a non-hypotriglyceridemic peroxisome proliferator-PFDA. 相似文献
74.
The most frequent form of idiopathic calcinosis is tumoral calcinosis (TC) which rarely occurs at young ages. We describe
here a TC case of a young boy with its light microscopy completed with electron microscopic examinations. X-ray microanalysis
revealed in the intracellular crystals CaCl2 besides the previously described hydroxyapatite. The significance of this finding is unknown at the moment. 相似文献
75.
The anaesthetic management of the surgical repair of a descending aortic aneurysm in a patient with large, bilateral, pulmonary
bullae is described. Anaesthesia for descending aortic surgery normally involves unilateral, positive-pressure ventilation,
an option which poses some risk of barotrauma in the presence of bilateral bullae. Patients with bullous disease commonly
have severe lung disease and thorough preoperative assessment and preparation are necessary. Intraoperatively, bilateral rupture
of the bullae could be catastrophic and preparations should be made for this possibility. In order to diminish this risk,
a surgical technique including preemptive collapse of the bulla by minithoracotomy and tube drainage, with use of a bronchial
blocker to the affected part of the lung may be used. If rupture occurs, then high frequency jet ventilation may be effective.
Use of a double lumen endobronchial tube may be advantageous for patients with either unilateral and bilateral bullae. Anaesthesia
for patients with bullae should avoid positive-pressure ventilation and nitrous oxide in order to limit the risk of barotrauma
from a ball valve mechanism. In this case, the risk of barotrauma was reduced by performing an inhalational induction of anaesthesia
and limiting peak inflation pressures during thoracotomy. It was elected to use positivepressure ventilation through a double
lumen endobronchial tube following chest incision. A high frequency jet ventilator was available but not employed. Anaesthetic
management was complicated by the presence of pleural adhesions, surgical approach directly through a bulla, and the requirement
for one lung ventilation.
The de i’aone descendante aecouverte cnez un pattent porde grosses bulles bilatérales d’emphysème est discutée, esthésie habituelle
pour une chirurgie de l’aorte descendante site une ventilation mécanique unilatérale et constitue ainsi sque additionnel pour
le porteur de bulles emphysémas bilatérales. Ces patients ont ordinairement des affections onaires graves et l’évaluation
et la préparation préopéraprennent une importance spéciale. Pendant l’intervention, pture de bulles bilatérales peut être
catastrophique et il se préparer à cette éventualité. Pour minimiser ce risque, technique chirurgicale qui inclut le collapsus
préventif de lle par minithoracotomie et drainage, avec installation d’un ieur bronchique sur la partie atteinte du poumon.
Si une re survient, le passage à la ventilation par jet à haute tence peut être salutaire. Le tube endobronchique à double
ère peut présenter des avantages aussi bien dans les cas ulles unilatérales que bilatérales. Chez ces patients, il vaut x
s’abstenir de ventiler avec une pression positive et du xyde d’azote afin de limiter le risque de barotraumisme soupape. Dans
ce cas-ci, on a réussi à limiter le risque arotraumatisme en réalisant une induction par inhalation réduisant la pression
d’inflation de pointe pendant la cotomie. Après l’incision thoracique, on a choisi d’utiliser tilation mécanique avec un tube
endobronchique à double ère. Un ventilateur à jet à haute fréquence était prêt mais as été utilisé. La gestion de l’anesthésie
a été compliquée par dhérences pleurales, par la rencontre d’une bulle d’emphysà l’incision et par l’obligation de ventiler
un seul poumon. 相似文献
76.
77.
I Segal A A Dubb L O Tim A Solomon M C Sottomayor E M Zwane 《British medical journal》1978,1(6111):469-472
The number of Africans in Johannesburg presenting with duodenal ulcers has steadily increased over the past 50 years. The characteristics of 105 patients with duodenal ulcer who presented a Baragwanath Hospital were compared with those of matched and unmatched samples of patients without gastrointestinal conditions in the same hospital. Men with duodenal ulcers were found to be significantly better educated than their controls, most had been born in the town, and more of them were employed at higher, though not the highest, educational levels. These data were used to test Susser's proposition that duodenal ulcers are associated with "early urbanisation." Johannesburg blacks with duodenal ulcer did seem to fit the pattern, but the relation between stress and duodenal ulcer remains unclear. 相似文献
78.
The use of Lepidium sativum in a plant bioassay system for the detection of microcystin-LR. 总被引:10,自引:0,他引:10
Toxin-producing cyanobacteria pose a worldwide health threat to humans and animals due to their increasing presence in both drinking and recreational waters. Detection of microcystins in water generally relies on specialised equipment and a delay of several days for transport and analysis. Little work has, however, been done on establishing a simple, cost-effective and sensitive plant bioassay for the detection of microcystin-LR (MCLR) in water at the WHO Tolerable Daily Intake guideline level of 1 microg/l. We investigated the effect of a MCLR extract at 1 and 10 microg/l on the growth of Lepidium sativum over 6 days. Exposure to 10 microg/l MCLR resulted in a significant decrease in root and leaf lengths and fresh weights of seedlings when compared to the controls. These results were consistent with seedlings exposed to pure MCLR at 10 microg/l. Seedlings exposed to 1 microg/l MCLR showed a significant decrease in root development from day 2 to day 6. Glutathione S-transferase and glutathione peroxidase activities were also significantly raised in plants from days 5 and 4, respectively, at both toxin levels investigated. 相似文献
79.
80.