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11.
用文献计量方法对《青海畜牧兽医杂志》国内外公开发行后7年间所刊载的论文及其作者进行了统计分析与探讨。主要项目有:论文数量及年度分布、论文学科内容分布、论文地域分布、论文机构分布、单位平均产文量、论文合著率、作者数量及地区分布、作者系统及单位分布、作者个人发文量、作者及单位合作度等。另外还确定出《杂志》1992~1998年的核心作者和核心单位。  相似文献   
12.
甘州区是典型的农业城市,地势平坦,土壤肥沃,自然条件优越,农副产品资源丰富,为畜牧业的发展提供了优越的条件.本文通过调查甘州区猪、牛、羊、鸡等活畜及其产品的市场行情和养殖现状,阐述了畜牧业发展的基本情况,分析了市场交易中的价格浮动,对我区的经济影响,并就当前发展形势提出了自己的几点建议.  相似文献   
13.
An estimate of the thickness of subcutaneous adipose tissue at differing positions around the body was required in a study examining body composition. To eliminate human error associated with the manual placement of markers for measurements and to facilitate the collection of data from a large number of animals and image slices, automation of the process was desirable. The open-source and free image analysis program ImageJ was used. A macro procedure was created that provided the required functionality. The macro performs a number of basic image processing procedures. These include an initial process designed to remove the scanning table from the image and to center the animal in the image. This is followed by placement of a vertical line segment from the mid point of the upper border of the image to the image center. Measurements are made between automatically detected outer and inner boundaries of subcutaneous adipose tissue along this line segment. This process was repeated as the image was rotated (with the line position remaining unchanged) so that measurements around the complete circumference were obtained. Additionally, an image was created showing all detected boundary points so that sites of measurement could be checked by visual inspection. This paper provides a detailed account of this macro, illustrates the effect of its components on the image, and the applicability of standard image processing techniques to veterinary imaging.  相似文献   
14.
The detection of 4-hydroxycoumarin rodenticides in poisoned domestic animals requires a highly sensitive method as tissue and serum levels of anticoagulants may be very low owing to rapid elimination, metabolism or post-mortem degradation. Thin-layer chromatography (TLC) and reversed-phase high-performance liquid chromatography (RP-HPLC) with fluorescence detection were used to identify the anticoagulants in spiked tissues and in suspicious samples. The analysis of ten suspicious samples highlighted the limitations of both methods. Only the three samples of baits were found positive by TLC whereas one of the five anticoagulants was detected in eight samples by RP-HPLC with fluorescence detection. Therefore, RP-HPLC with fluorescence detection proved to be the more sensitive method for detecting low levels of 4-hydroxycoumarins in blood serum, liver and ingesta, whereas TLC is usually sufficient for analysing baits.Abbreviations RP-HPLC reversed-phase high-performance liquid chromatography - TLC thin-layer chromatography  相似文献   
15.
Eight strains of Taylorella equigenitalis were identified by a polymerase chain reaction using a primer pair specific to the 16S rDNA of T equigenitalis. These eight strains were chosen because they had previously been shown to represent eight distinct genotypes by pulsed-field gel electrophoresis analysis after separate digestion of the genomic DNA with ApaI or NotI. The eight strains could be classified into six or seven types by random amplified polymorphic DNA analysis using different kinds of primers. Amplified rDNA restriction analysis after separate digestion with five restriction enzymes, including AluI and MboI, of the 1,500 bp fragments of rDNA amplified by polymerase chain reaction did not discriminate the genomic variations among the eight strains of T equigenitalis. Thus, pulsed-field gel electrophoresis was shown to discriminate these eight organisms better than random amplified polymorphic DNA analysis, while amplified rDNA restriction analysis was found to be unsuitable for subtyping T equigenitalis.  相似文献   
16.
Sensitivity analysis is a part of mathematical programming solutions and is used in making nutritional and economic decisions for a given feed formulation problem. The terms shadow price and reduced cost are familiar linear program (LP) terms to feed formulators. Because of the nonlinear nature of stochastic programming (SP), different methods and terminology are used to define shadow prices and reduced costs. The Lagrange multiplier is used instead of shadow price to describe marginal value of nutrients. Reduced gradient is used instead of reduced cost to describe the price at which ingredients not used in the formulation would be included in the solution. A spreadsheet feed problem was set up with 11 ingredients and 11 constraints. The LP and SP solutions were determined using the Excel Solver algorithm. Two problems compared LP and SP solutions at 50 and 69% probabilities for the protein constraint. All other constraints were held at a 50% probability. Results for the 50% probability comparison showed that the feed formulations, as expected, were the same for both LP and SP. Wheat was not included in the solution. The LP reduced cost and the SP reduced gradient for unused wheat were equivalent. The LP shadow prices and the SP Lagrange multipliers were equivalent. Results for the 69% probability problem showed a difference in the formulated rations. The LP reduced cost was $34.25 and the SP reduced cost was $34.52, showing the respective amounts that the cost of wheat would have to be reduced to be included in the solution. The shadow price and the Lagrange multiplier were $2.73 and $2.71, respectively, for the amount of increase in diet cost that could be expected by a unit of change in the protein requirement. Some differences in precision were noted with the results. A caveat is that, because of nonlinearity, sensitivity analysis for SP is valid only for the single point of the optimal solution.  相似文献   
17.
为实现喀纳斯景区山地草甸的可持续管理,本研究通过设置无牧对照(NG)、单牧马-轻牧区(HG)、牛马混牧-重牧区(MG)三种放牧方式,探求提高山地草甸生态系统多项生产和生态功能协同性的放牧方式。结果表明:不同放牧方式下山地草甸的生产功能放牧后较放牧前均有下降,生态功能中土壤N:P、植物N:P、凋落物N:P放牧后较放牧前均升高,其他生态功能降低,但HG的Shannon-Wiener指数在放牧后变化不大;NG的土壤呼吸速率和植被C:N升高。在山地草甸生态系统生产和生态功能的权衡关系中,权衡、协同和不相关关系同时存在,与牧草产量,草地质量指数相关的生产和生态功能存在协同关系;与植被平均高度、土壤呼吸速率、土壤碳储量相关的生产和生态功能存在权衡关系,其余指标为不相关关系。综上所述,最适放牧方式为HG,其协同关系最佳。  相似文献   
18.
内蒙古是全国重要的乳品生产基地,乳品产业是该地区的特色产业、优势产业,其进出口贸易对内蒙古地区经济发展具有十分重要的作用。采用数据分析与理性思考相结合的方式,对内蒙古乳品产业发展现状及进出口情况进行分析,探讨该地区乳品贸易存在的问题,积极探索对策措施,以提高内蒙古乳品在国际贸易中的竞争力。  相似文献   
19.
20.
家蚕B型清道夫受体基因的鉴定及系统发生与表达分析   总被引:1,自引:0,他引:1  
B型清道夫受体(SR-B)是清道夫受体超基因家族成员,参与机体的脂类代谢、动脉粥样硬化形成或保护、宿主免疫损害防御、凋亡细胞清除和细胞粘附等重要生命过程。基于家蚕全基因组数据,利用比较基因组学方法,鉴定获得了14个家蚕B型清道夫受体基因,这些基因分布在至少5条染色体上,其内含子的大小从几十到近万个碱基对。系统发生分析表明,14个家蚕B型清道夫受体基因分布在3个类群:第1类群中分布的9个基因和第3类群中分布的3个基因,分别与类群中其它昆虫的同源基因形成明显的直系同源关系;第2类群中分布有2个基因,此类群中不同昆虫的同源基因之间的进化关系较为复杂。EST数据和芯片数据分析表明,多数家蚕B型清道夫受体基因具有转录活性。RT-PCR检测结果显示,有8个家蚕B型清道夫受体基因在5龄第3天幼虫组织中表达,并具有不同的表达模式,推测这些基因可能行使不同的功能。研究结果为进一步诠释家蚕B型清道夫受体基因的功能奠定了基础。  相似文献   
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