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Phosphate influx and extracellular phosphatase activity in barley roots and rose cells 总被引:4,自引:0,他引:4
R. B. LEE 《The New phytologist》1988,109(2):141-148
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ABSTRACT An assessment on the biological control potential with the fish muddy loaches (Misgurnus mizolepis) was conducted against naturally bred Culex pipiens pollens larvae in four ponds (A, B, C and D) in Busan from July through September, 2001. Predation of the fish at 3 different release rates of 4,5, and 6 fish/m2 resulted in mostly over 90% mosquito control from the first week after treatment through the end of the survey period for 11 weeks. There were no significant difference among the release rates of fish at the 5% level of probability. However, substantial controls of 43.0% and 25.9% were obtained from pond C during the 3rd and 7th weeks after the fish introduction, respectively. The results of those two weeks showed a lower biological control by the introduced larvivorous fishes. This might be due to the presence of heavy organic matters including aquatic weeds and/or severely polluted water from sewage in pond C. The aquatic weeds covered the pond's water surface which may have affected the deterioration of mosquito preying in favor of aquatic weeds. Also, the fishes were observed to avoid severely contaminated sewage water in some parts of ponds A and C where more mosquito larvae were found. 相似文献
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(一)乙型脑炎疫苗在用每分钟2,000转的速度沉澱20分钟後,疫苗中的总氮含量此较不沉澱的减少50%以上,但是疫苗的效价不论在其制成时或在保存一年的各时期
内,都没有比不沉澱的低。
(二)用含有5%的乳醣和一些鹽灰的溶液裂偏的疫苗的免疫效僵在各保存时期内都比用普通的生理鹽水制偏的疫苗为高,而且比较稳定。
(三)本文同时讨论了福尔马林的使用量和疫苗中蛋白質的含量的关系。 相似文献
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LEE ST 《California medicine》1952,76(4):294-296
Cul-de-sac puncture for introduction of a culdoscope is easily made with the patient in the knee-chest position. With the use of the instrument, the pelvic organs can be viewed clearly. Culdoscopic examination of 45 patients was carried out. In all cases in which laparotomy was done after the examination, the culdoscopic observations and diagnosis were confirmed. In no case in which tubal pregnancy was present, was the diagnosis missed in culdoscopic examination. Patients were only slightly uncomfortable after the examination. There was no evidence of pelvic peritonitis in any patient, and no pregnant patient aborted as a result of the procedure. 相似文献