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81.
Recurrent herpes in the rabbit and man   总被引:11,自引:0,他引:11  
Herpesvirus was present in secretory glands and frequently in tears of rabbits with recurrent herpetic keratitis even in the absence of corneal lesions. In normal people, herpesvirus could be cultured from saliva and tears. Chronic virus multiplication in structures such as the lacrimal and salivary glands, rather than latency, may cause recurrent herpetic disease.  相似文献   
82.
Summary Studies were conducted to determine whether soils that showed enhanced biodegradation of organophosphate insecticides had significantly different enzyme activities from those in the same soils with no previous exposure to the insecticides. Twenty-one pairs of soils were collected from farms in the Midwest where chlorpyrifos, terbufos, fonofos, or phorate had failed to protect corn (Zea mays L) from corn rootworm (Diabrotica sp). Each soil was analyzed for acid and alkaline phosphatase, phosphodiesterase, phosphotriesterase, and dehydrogenase activities. Over 40% of the insecticide-treated soils had higher acid phosphatase activity than the fence row soils which had no previous exposure to the insecticide. Over twothirds of the soils treated with fonofos had higher acid phosphatase and phosphotriesterase activity than the fence row soils. If these enzymes are not directly involved in the biodegradation of the insecticitde, they may be indicative of enhanced biodegradation and may be used to predict which soils may be prone to insecticide failure.Contribution from the Soil-Microbial Systems Laboratory, Natural Resources Institute, USDA-ARS, Beltsville, MD 20705, USA  相似文献   
83.
A model for estimating the remediation costs at contaminated sites is developed, in which the predictor variable is a composite of surface, subsurface, and contaminant risk factors. Calibration of the model is performed at 83 sites in an urbanized watershed with diverse surface geology in southeastern Michigan. These test sites exhibited different extents of contamination, including some where only soil was contaminated, and others where soil and groundwater were contaminated. The model was then applied to 79 sites with multiple contamination extents within different watersheds in North America, Europe, Australia, and Africa. The results indicate a very high correlation between the estimated and actual remediation costs at these sites. This model thus has the potential for providing reliable estimates of remediation costs across a broad array of soil and groundwater contamination scenarios, including dense nonaqueous phase liquid (DNAPL) contamination in sandy soil and lead in clay soil.  相似文献   
84.
85.
The electrophoretic pattern of RNA molecules that are synthesized in vitro in tracheal epithelium from hamsters deficient in vitamin A differs from that of RNA synthesized in normal, pair-fed control hamsters. There is less RNA of low electrophoretic mobility in the epithelial cells deficient in vitamin A. This alteration is reversed after the deficient animals have been treated with vitamin A.  相似文献   
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87.
编者按:虱子、恙虫、家禽壁虱和鸡蚤是家禽业中常见的体外寄生虫.虽然禽舍苍蝇不是寄生虫,但是备受家禽生产者的关注,尤其对于笼养蛋鸡生产者.这些体外寄生虫对家禽业的危害日益得到重视.本专题就上述几种体外寄生虫的生活习性和药物控制措施进行总结,希望为广大读者提供借鉴.  相似文献   
88.
89.
Depression in infant monkeys separated from their mothers   总被引:2,自引:0,他引:2  
The mothers of four pigtail (Macaca nemestrina) infants living in a group were removed for 4 weeks. All infants reacted initially with agitation. Three of the four infants then became severely depressed. The depression lasted about a week and was strikingly similar to the "anaclitic depression" of human infants who lost their mothers. When they were reunited, all four dyads showed a marked and prolonged intensification of the mother-infant relationship.  相似文献   
90.
Glutamate decarboxylase (GAD; E.C. 4.1.1.15) converts glutamate to gamma-aminobutyric acid (GABA), the major inhibitory neurotransmitter in the vertebrate central nervous system. This report describes the isolation of a GAD complementary DNA clone by immunological screening of a lambda gt-11 brain complementary DNA expression library. The fusion protein produced by this clone catalyzes the conversion of glutamate to GABA and carbon dioxide, confirming its identity as GAD. Antibodies to beta-galactosidase remove GAD enzymatic activity from solution, showing that this activity is associated with the fusion protein. In immunoblotting experiments all three available antisera to GAD reacted with the fusion polypeptide and with two major polypeptides (molecular size, 60,000 and 66,000 daltons) in brain extracts.  相似文献   
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