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Sodium selenite was mixed in a commercial pig food so as to increase the original selenium content (0.126 ppm) by 1.2 ppm. The supplemented food was given to 7 pigs during 78 days. A control group of as many pigs was given the non-supplemented commercial food. The pigs were killed, starting 4 hours after the last selenium-supplemented food had been given and then with intervals during the next 14 days. Small but significant increases of tissue selenium were noticed in liver and striated muscle as compared with the control animals. The kidneys showed no increase. 相似文献
224.
The radii of radiation-induced color halos(RICHs) surrounding radioactive mineral inclusions in mica generally correspond closely to the calculated range of common uranogenic and thorogenic alpha particles in mica. Many exceptions are known, however, and these variants have led investigators to some rather exotic interpretations. Three RICHs found in quartz are identified as aluminum hole-trapping centers. Whereas the inner radii of these RICHs closely match the predicted range of the most energetic common alphas(39 micrometers), the color centers observed extend to 100 micrometers. Migration of valence-band holes down a radiation-induced charge potential might account for enigmatic RICHs. Such RICHs provide natural experiments in ultraslow charge diffusion. 相似文献
225.
Dunnick W 《Science (New York, N.Y.)》1989,245(4921):993-994
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Metzger WP 《Science (New York, N.Y.)》1989,244(4909):1200-1201
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McMurphy RM Cribb PH 《The Canadian veterinary journal. La revue veterinaire canadienne》1989,30(1):37-41
This study was designed to investigate the effect of the nasotracheal insufflation of oxygen at a flow rate of 15 L/min on the arterial partial pressure of oxygen during the recovery period following inhalation anesthesia in the horse. It has been stated that this is a suitable flow rate to prevent postoperative hypoxemia but without any experimental evidence to support those statements. Horses being used for the study of healing of cartilage were anesthetized on two separate occasions. Following one period of anesthesia they were allowed to recover breathing room air, and following the other period of anesthesia oxygen was insufflated into the trachea at 15 L/min throughout the recovery period. This permitted each horse to act as its own control and allowed statistical analysis using Student's t-test for paired samples.
The insufflated horses had a higher arterial partial pressure of oxygen during the recovery period than did the noninsufflated horses (p < 0.05).
相似文献230.
A survey of anthelmintic resistance on ten goat farms was carried out. The criterion for resistance was a faecal egg count reduction (FECR) of <90 percent based on arithmetic means of 11 to 19 goats per group. It was found that nine of the ten farms harboured nematodes resistant to oxfendazole when used at 5mg/kg although on two of these, the FECR's were 89.2 percent and 89.8 percent. Post treatment larval cultures indicated Haemonchus, Ostertagia and Trichostrongylus were the resistant genera involved. On none of the ten farms was resistance to oral ivermectin at 0.2mg/kg detected. 相似文献