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31.
为了研究延胡索酸泰妙菌素对猪支原体肺炎的临床疗效,选用体重90 kg左右的2月龄健康杜洛克长白杂交猪,通过建立疾病模型和疗效评价指标判别延胡索酸泰妙菌素的治疗效果。结果表明,按1000 kg饲料添加100 g或200 g延胡索酸泰妙菌素,可以显著减轻感染猪的临床症状和病理变化,提高猪的增重,其效果优于磷酸泰乐菌素预混剂。  相似文献   
32.
[目的]研究单羰基姜黄素类似物(代号B06)对Ⅱ型糖尿病大鼠非酒精性脂肪肝糖脂代谢紊乱的影响。[方法]应用高糖高脂饲料喂养,小剂量STZ干扰建立Ⅱ型糖尿病大鼠模型[1],并随机分模型组、A75治疗组、C66治疗组、正常对照组,各组均灌胃治疗12周;检测各组大鼠血生化指标[2]。[结果]单羰基姜黄素类似物能明显改善试验性Ⅱ型糖尿病大鼠的血糖升高,FINS明显低于模型组;肝脏TC、血清TG、TC有明显的降低作用,对血清HDL有明显的升高作用,有统计学意义;[结论]单羰基姜黄素类似物对Ⅱ型糖尿病大鼠非酒精性脂肪肝有一定的治疗作用。  相似文献   
33.
Bernd Ehret 《Geoderma》2010,160(1):111-88
A new rock classification method for ground penetrating radar (GPR) data is presented for cases where no additional geological information is available from boreholes. There are non-linear relationships between petrophysical properties of rocks and electromagnetic waves which can be handled using two methods derived from statistical learning theory on pattern recognition. An investigation was carried out looking at proving the feasibility of the method in principle for use on synthetic models as well as measurement data. The different learning methods were also compared.The method is based on multivariate statistical learning algorithms for the discrimination of layer boundaries between different rocks. The discrimination developed works with artificial neural networks (ANN) and support vector machines (SVM). The processing procedure starts with geological models with varying petrophysical rock parameters, which are to be sought in the measurement data. The models are used to generate synthetic radargrams from which rock properties can be derived using wave attributes. The calculated values of the wave attributes are stored in a multivariate data pool. This data pool is used to train the ANN and the SVM. The same wave attributes are derived from the GPR data and also saved in a data pool. This generates two data sets for pattern recognition with which to directly classify rock layers. Wave attributes can therefore be used to derive the non-linear correlative relationships between rock properties and GPR data by the weighted matrices of ANN and SVM.The presented method can be used to match reflections in the GRR data directly with the layer boundaries of rock formations. The classification of a boundary horizon between rock salt and anhydrite is demonstrated on synthetic GPR traces and measurement data from a rock salt mine. The advantage of this method is that rock classification is not a priori dependent on borehole data.  相似文献   
34.
To observe the clinical therapeutic effect of 30% praziquantel injection on buffalo schistosomiasis, the sick buffalos naturally infected with Schistosoma japonicum were selected by miracidium hatching method. In experimental clinical trials, sick buffalos were randomly divided into five groups, high-dose (20 mg/kg), middle-dose (10 mg/kg) and low-dose (5 mg/kg) praziquantel injection groups, praziquantel tablet group (30 mg/kg) and positive control group. After the treatment of 30 d, the negative conversion rate of miracidium were 100.0%, 100.0%, 77.8% and 85.7%, respectively, in praziquantel injection groups with the high, middle and low dose and oral medication group. In expanded clinical trials, the sick buffalos were randomly divided into two groups, praziquantel injection group (10 mg/kg, i.m.) and praziquantel tablet group (30 mg/kg). The results showed that, the negative conversion rate of miracidium were all 100% in the former 52 patients and the latter 6 patients after 30 d. The research confirmed that praziquantel injection was significantly effective in the treatment of buffalo schistosomiasis and convenient for administration. It was concluded that 30% praziquantel injection could replace the traditional oral praziquantel tablet for the treatment of buffalo schistosomiasis, and the recommended dose was 10 mg/kg.  相似文献   
35.
利用人工神经网络以及相关地形属性绘制数字土壤地图   总被引:2,自引:0,他引:2  
Detailed soil surveys involve costly and time-consuming work and require expert knowledge. Since soil surveys provide information to meet a wide range of needs, new methods are necessary to map soils quickly and accurately. In this study, multilayer perceptron artificial neural networks (ANNs) were developed to map soil units using digital elevation model (DEM) attributes. Several optimal ANNs were produced based on a number of input data and hidden units. The approach used test and validation areas to calculate the accuracy of interpolated and extrapolated data. The results showed that the system and level of soil classification employed had a direct effect on the accuracy of the results. At the lowest level, smaller errors were observed with the World Reference Base (WRB) classification criteria than the Soil Taxonomy (ST) system, but more soil classes could be predicted when using ST (7 soils in the case of ST vs. 5 with WRB). Training errors were below 11% for all the ANN models applied, while the test error (interpolation error) and validation error (extrapolation error) were as high as 50% and 70%, respectively. As expected, soil prediction using a higher level of classification presented a better overall level of accuracy. To obtain better predictions, in addition to DEM attributes, data related to landforms and/or lithology as soil-forming factors, should be used as ANN input data.  相似文献   
36.
采用描述分析得到白扇乳16个感官性质。用定量描述分析评定感官性质的强度。各样品感官性质及其强度的主分量分析表明,前5个主分量可以解释81.76%的总变异,16个感官性质中以硬度、结着力、粘贴性、粗糙度、苦、甜、咸、涩、豆腥气、酸为主要因子,而前4个表示组织特征的性质能解释最多的变异。从各样品在各主分量的分值图可以直接看出样品间的感官差异。  相似文献   
37.
Utilizing soil electrical conductivity (EC) measurements and terrain attributes for precision management will require secondary soil information for adequate interpretation. The objective of this study was to determine whether readily available second-order soil surveys were of adequate quality to aid with interpreting soil EC and terrain data. For three locations in Kentucky, USA, first-order soil surveys were created, second-order surveys reports were obtained, elevation was measured and used to calculate terrain attributes (slope, aspect, plan curvature, profile curvature), and bulk soil electrical conductivity was measured. Three analytical methods (an ordinary least squares analysis and two random field analyses), visual map assessment, and examination of least-squares means were used to assess the relationships between soil EC measurements, terrain attributes and first- and second-order soil surveys. The OLS and random field analyses were problematic. However, the ranking of the OLS F-statistics appeared to reflect the general relationship between landscape variables and first-order soil surveys. The landscape variables related particularly well with soil properties that had been impacted by past soil erosion. Unfortunately, however, second-order soil surveys in this study were not created at suitable scales to adequately interpret EC and terrain data regarding erosion history or other attributes. While these surveys may provide some useful information, field measurements, sampling, and observations will likely be required to develop high quality interpretations of soil EC and terrain attribute data.  相似文献   
38.
骨质疏松症是以骨量减少、骨的微观结构退化为特征,致使骨的脆性增加并易于发生骨折的一种全身性骨骼疾病,是当前严重危害人类特别是绝经妇女和老人的疾病之一.近年来出现了许多预防和治疗骨质疏松症的药物,极大地推动了骨质疏松症理论基础的完善和临床治疗研究.就该领域的研究进展进行了简要综述.  相似文献   
39.
河南开封土壤养分变化特征及其持续利用途径研究   总被引:6,自引:0,他引:6  
武继承  龚子同  姚健 《土壤通报》2001,32(4):155-159
通过 1 984~ 1 998年河南开封不同土壤耕层有机质与氮磷钾养分分析 ,论述了不同农业利用方式和农田管理措施下不同土壤耕层养分的时空变化特征和硝态氮累积特性 .由于“重氮磷 ,轻有机肥 ,忽视钾素补给” ,土壤养分变化的总趋势以下降 ,钾素耗竭性明显 .土壤养分空间变化较为复杂 ,但不同土壤间耕层养分为普通淡色潮湿雏形土 >底锈干润雏形土 >石灰淡色潮湿雏形土 >灌淤旱耕人为土 >简育干润雏形土 >干润砂质新成土 .硝态氮累积表现为由上至下递减或由上至下递增和相对积累于土体某一深度 .最后研究提出了土壤持续利用的有效技术途径 .  相似文献   
40.
Five management treatments have been applied to a calcareous grassland since 1974 to study their efficiency in maintaining high diversity of grassland species. The treatments were: continuing sheep grazing, mowing, mulching, burning and leaving fallow (unmanaged). After 25 years of management, the treatments mowing and mulching resulted in a species composition similar to that from grazing by sheep. Thus, mowing and mulching can be useful management alternatives to grazing. In contrast, both burning and leaving fallow considerably changed the species composition. The changes were similar in both treatments and neither can be recommended for management purposes. We also evaluated eight traits with assumed sensitivity to the treatments (life form, life cycle, growth form, runners, lateral spread, fecundity, seed mass, germination season). In 1999, all traits except life cycle were found to respond to the different treatments. Trait response is discussed in detail.  相似文献   
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