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131.
柞蚕幼虫酯酶同工酶的组织器官及发育时期特异性   总被引:1,自引:0,他引:1  
应用聚丙烯酰胺凝胶电泳方法,对柞蚕不同发育时期及不同组织器官酯酶同工酶的特异性进行了研究,结果表明:柞蚕酯酶同工酶在柞蚕幼虫不同组织器官中的活性及种类差异很大,丝腺中无酯酶存在或者活性极低;血淋巴和马氏管中有少量酯酶存在,但活性较弱;酯酶在柞蚕脂肪体及中肠组织中有强的活性,并且同工酶种类较多。酯酶同工酶在柞蚕幼虫不同发育时期其活性和同工酶带数量上有一定的特异性,但主带迁移率相同。  相似文献   
132.
阐述现代生态农业产业必要性,并结合现代生态农业产业现状做出相应思考,对存在的种种问题进行探析。  相似文献   
133.
种业新政下着力提升河南省种企发展的若干思考   总被引:6,自引:5,他引:1  
文章在充分认识当前我国种业新政和现代种业发展形势的基础上,对河南省种子企业发展存在的主要问题进行了较为详尽的分析和阐述,并提出应从改革完善种业创新体制、扶持"育繁推一体化"优势企业、加大政策保障支持力度、加强种子市场监督管理及人才队伍建设等方面着力提升河南省种子企业发展的思路和建议,以期为推动河南省乃至全国种业的发展提供一定的参考依据。  相似文献   
134.
农业科研档案管理是现代科研管理工作的重要组成部分,是农业科研活动的重要环节。随着国家对农业科技体制改革的不断深化,农业科研档案收集、归档、流向等管理工作出现了新的问题。分析了当前我国农业科研档案管理中存在的问题及其原因,并提出了农业科研档案管理的创新思路。  相似文献   
135.
136.
高职高专图书馆是完成学校教学任务和实现学校总体目标的重要机构。目前,高校图书馆正向着从优化资源建设结构、整合文献资源、构建公共服务平台、扩大文献信息服务能力、提升高数图项目建设效益、构建学校文献保障体系、服务地方经济文化建设等方面发展,对图书馆读者服务的要求越来越高。针对如何做好高职高专学校图书馆读者服务,提出一些自己的思考及建议。  相似文献   
137.
Working animals provide an essential transport resource in developing countries worldwide. Many of these animals are owned by poor people and work in harsh environments, so their welfare is a cause for concern. A protocol was developed to assess the welfare of working horses, mules and donkeys in urban and peri-urban areas, using direct observation of health and behaviour parameters. In this study, 4903 animals used for draught, pack and ridden work in Afghanistan, Egypt, India, Jordan and Pakistan were assessed between December 2002 and April 2003. The data showed that donkeys were more likely than mules or horses to demonstrate avoidance or aggressive behaviour towards an observer, while horses were most likely to make a friendly approach. Fewer than 8% of working equines had abnormal mucous membranes, ectoparasites or poor coat condition. Body lesions occurred predominantly in the areas of the breast/shoulder, withers and girth in all three species, with mules having the highest prevalence of lesions in these areas (22.5, 21.3 and 28.4%, respectively). Among horses and donkeys, the prevalence of these lesions was influenced by the type of work carried out. Lesions on the head, neck, ribs, flank and tail base were seen in less than 10% of animals. Across all three species approximately 70% of animals were thin, having a body condition score (BCS) of 2 or less on a scale of 1–5 (1, very thin; 5, very fat) and more horses were in very thin condition (BCS 1) than mules or donkeys. Over 75% of animals demonstrated limb deformities and abnormalities of gait. The results of this study are being used as the initial stage of a long-term strategy to inform priorities for welfare interventions in working equines and to establish a welfare benchmark. Subsequent stages will rank the welfare concerns identified, assess the contributing risk factors and implement specific interventions to address these risks. Following intervention, success in improving welfare will be measured by repetition of this protocol and comparison with the benchmark.  相似文献   
138.
We developed three different knowledge-dissemination methods for educating Tanzanian smallholder farmers about mastitis in their dairy cattle. The effectiveness of these methods (and their combinations) was evaluated and quantified using a randomised controlled trial and multilevel statistical modelling. To our knowledge, this is the first study that has used such techniques to evaluate the effectiveness of different knowledge-dissemination interventions for adult learning in developing countries.

Five different combinations of knowledge-dissemination method were compared: ‘diagrammatic handout’ (‘HO’), ‘village meeting’ (‘VM’), ‘village meeting and video’ (‘VM + V’), ‘village meeting and diagrammatic handout’ (‘VM + HO’) and ‘village meeting, video and diagrammatic handout’ (‘VM + V + HO’). Smallholder dairy farmers were exposed to only one of these interventions, and the effectiveness of each was compared to a control (‘C’) group, who received no intervention. The mastitis knowledge of each farmer (n = 256) was evaluated by questionnaire both pre- and post-dissemination.

Generalised linear mixed models were used to evaluate the effectiveness of the different interventions. The outcome variable considered was the probability of volunteering correct responses to mastitis questions post-dissemination, with ‘village’ and ‘farmer’ considered as random effects in the model. Results showed that all five interventions, ‘HO’ (odds ratio (OR) = 3.50, 95% confidence intervals (CI) = 3.10, 3.96), ‘VM + V + HO’ (OR = 3.34, 95% CI = 2.94, 3.78), ‘VM + HO’ (OR = 3.28, 95% CI = 2.90, 3.71), ‘VM + V’ (OR = 3.22, 95% CI = 2.84, 3.64) and ‘VM’ (OR = 2.61, 95% CI = 2.31, 2.95), were significantly (p < 0.0001) more effective at disseminating mastitis knowledge than no intervention.

In addition, the ‘VM’ method was less effective at disseminating mastitis knowledge than other interventions. Combinations of methods showed no advantage over the diagrammatic handout alone. Other explanatory variables with significant positive associations on mastitis knowledge included education to secondary school level or higher, and having previously learned about mastitis by reading pamphlets or attendance at an animal-health course.  相似文献   

139.
对梁启超前期的新闻思想 ,用“去塞求通”四个字是无法全面准确地加以概括和反映的 ,“去塞求通”仅仅是其新闻思想的一部分。梁启超前期的新闻思想集中表现在对“报馆有益于国事”及“报章体例”的探讨上 ,提出了开风气、求通达、教愚民的报刊功能观以及文义并举的新闻业务思想。  相似文献   
140.
The global biodiversity crisis extends to autochthonous local breeds of livestock. There is an increasing danger that these rare breeds become extinct and with them their locally adapted gene pool. Modern molecular tools such as parentage testing using microsatellite genotyping are powerful in guiding management and conservation. We tested nine microsatellite markers in three Croatian horse breeds and obtained high exclusion probabilities (EPs) for the most common test scenario ‘one parent and offspring known and the other parent tested’ (99.9% in Posavina and Croatian Coldblood and 99.3% in Lipizzaner), despite that Lipizzaner has an overall lower genetic variability at microsatellite loci. To become a useful tool in breed management in countries with developing economies, genetic screening systems must be designed to be statistically powerful yet economically viable. Therefore, a suite of six markers that can be run in two multiplex systems and which still gives high exclusion probabilities (99.5% in Posavina and Croatian Coldblood and 98% in Lipizzaner) was chosen.  相似文献   
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