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中药组方抑制鸡大肠杆菌及临诊治疗试验   总被引:5,自引:0,他引:5  
用茜草秧、薄公英等11味中药组方对鸡大肠杆菌耐药菌株和非耐药菌株作体外抑菌及临诊治疗试验。结果,中药组方对两菌株都有较好的体外抑菌效果;临床治疗有效率100%,治愈率达96%以上。  相似文献   
54.
The utilization of olfactory responses of predators and ­parasitoids to the allelochemicals emitted by phytophagous arthropods and their host plants is becoming more important in biological pest control. The effects of three weed ­species, i.e. wormwood Artemisia vulgaris L., tansy Tanacetum vulgare L. and stinging nettle Urtica dioica L., which were planted as accompanying vegetations into a lettuce field, were examined for the predatory species Coccinella septempunctata L., Adalia bipunctata (L.), Propylea quatuordecimpunctata (L.) (Coleoptera, Coccinellidae) and Chrysoperla carnea (Steph.) (Neuroptera, Chrysopidae), as well as for aphids during the summer of 2000. The presence of weeds significantly increased the density of adults and larvae of the predators on the lettuce plants in relation to the control (lettuce field without weeds). However, the differences remained smaller for eggs and pupae. C. septempunctata tended to be the most abundant species, followed by P. quatuordecimpunctata. Remarkable differences among the attractiveness levels of the weeds in the 3 treatments were not observed. The increased populations of predators were accompanied by significantly reduced infestation rates with aphids in the treatments in relation to the control. Myzus persicae Sulzer was in general the most abundant aphid species followed by Nasonovia ribisnigri Mosley and Macrosiphum euphorbiae Thomas. The results of the present study are discussed with respect to the management of agroecosystems and the use of weeds in biological control.  相似文献   
55.
Electroencephalogram (EEG) signals are the electrical activities in the cortex or on the surface of scalp caused by the physiological activities of the brain which play a key role in the diagnosis of brain and the functional determination of brain. The authors discuss some methods for processing EEG signals from the view of the frequency domain and time domain, especially introduce some time-frequency analysis methods such as Wigner distribution, wavelet transform and matching pursuit etc. , ANN and non-linear analysis for EEG signals processing.  相似文献   
56.
Scientific method was necessary for road decision maker to select high cost effect ratio pavement structure scheme. According to the fact that many uncertain knowledge and information existed in the process of evaluating the expressway asphaltpavement structure schemes, an evaluation model of pavement structure schemes based on uncertainty measurement was put forward;This method implemented ordered division of assessment space,and could recognize and rank different schemes by comprehensive measurement matrix of multiple indexes. three typical design programs of expressway asphalt pavement structure were evaluated by that model.It is shown that the assessment can objectively reflect the comprehensive performance of asphalt pavement structure ,which provides a new method and way for evaluation of pavement structure schemes.  相似文献   
57.
秃杉种质资源迁地保存育苗技术研究   总被引:4,自引:1,他引:4  
总结研究了13a来在地处亚热带在江苏省宁镇丘陵地区引种原产云贵高原、鄂西山地的珍稀树种秃杉获得在播种育苗与无性繁殖技术成果。该项 成果认为采用氧化剂消毒浸种侵芽,适时防治幼苗猝倒病,适度遮荫保湿,当年冬季防寒保苗等组装技术,可使每公斤种子产秃杉合格苗2.20万-5.60万株,1年生苗安全越冬;采用砻糠灰作基质,用KMnO4液浸条,在秋冬季扦插,生根率达41.3%-54.4%;用电子叶间隙喷雾,以珍珠岩作基质,或在日光温室内用塑料薄膜封闭保温,用KMnO4液浸条等技术,可使插条生根率达72.6%和76.1%。  相似文献   
58.
试验表明我国田间温州蜜柑上的船形叶多数不是由温州蜜柑萎缩病毒(SDV)所致,其中部分具有嫁接传染性,经ELISA检测带柑桔衰退病毒(CTV)。用CTV接种温州蜜柑,可致船形叶症状。推测我国田间温州蜜柑船形叶症状主要系CTV所致。  相似文献   
59.
ZHU Li  DONG Zhi  ZHANG Guo-dong 《园艺学报》2010,26(9):1728-1733
AIM: To observe the effect of cannabinoid receptor (CB1R) agonist WIN55-212-2 on the expression of brain-derived neurotrophic factor (BDNF), c-Fos and protein kinase A beta-catalytic subunit (PKAC-β) in cerebrum cortex after intracerebral hemorrhage (ICH) in rats. METHODS: The intracerebral hemorrhage model of rat was made by the injection of collagenase Ⅶ, and WIN55-212-2 was intraperitoneally (ip) injected 30 min later. The rats were killed for sampling the brain tissues as specimens 24 h after ICH. The methods of immunohistochemical analysis and Western blotting were adopted to detect the expression of PKAC-β and BDNF. The mRNA expression of PKAC-β, c-Fos and BDNF was determined by RT-PCR. RESULTS: WIN55-212-2 obviously improved some nervous deficit symptoms and increased the expression of BDNF at mRNA and protein levels with upregulating the mRNA expression of c-Fos and downregulating the expression of PKA at mRNA and protein levels in the ipsilateral cerebral cortex. The proteins of PKAC-β, c-Fos and BDNF were expressed on the membrane or nucleus of the neuron or in the cytoplasm of glial cells, respectively. CONCLUSION: The expression of BDNF is induced not only by upregulation of c-Fos, but also by downregulation of PKA in WIN55-212-2 treated rats.  相似文献   
60.
免耕稻油轮作模式探讨   总被引:1,自引:0,他引:1  
稻油轮作是保障我国粮油安全的重要耕作制度.从农业节肥减药、生态高效、机械化轻简栽培等视角出发,提出了适合湖南地区的免耕稻油轮作模式,阐述了关键技术,分析其可行性,并对其可持续发展进行展望.  相似文献   
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