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61.
本文就小反刍兽疫的病原学、流行病学、临床诊断、实验室诊断、综合防控等方面进行了全面的概述,以期对小反刍兽疫的防控工作提供帮助。  相似文献   
62.
ABSTRACT

In September 1992 Washington State University at Tri-Cities became one of the nation's first subscribers to OCLC's FirstSearch in order to make user-accessed AGRICOLA and its other automated indexing services available free of charge to everyone on the Ethernet, the branch campus computer network, with its telnet access to the Internet. Arrival of user-accessed AGRICOLA at WSU Tri-Cities was timely due to the addition of a new bachelor of science degree program in the integrated cropping systems typical of the surrounding Columbia Basin arid lands region; the opening of a Food and Environmental Quality Laboratory to monitor local use of pesticides and other substances; the presence on campus of the Cooperative Extension Services District Office, covering eleven counties in the area; and close links with the WSU Agriculture Research and Extension Center at nearby Prosser.  相似文献   
63.
In response to customer concerns related to gluten strength in commercial baking, the Canadian Grain Commission assessed whether the Canadian Short Process (CSP) test bake method was generating useful data related to intrinsic strength of wheat varieties. Assessment of CSP loaf volume data for Canadian variety trials spanning 2003 to 2013 showed very little correlation with dough strength parameters as measured by farinograph and extensigraph. A lean no time (LNT) test baking method was developed that can better discriminate genotypes and provide objective indicators of the effect of intrinsic dough strength on baking quality. From early method development, through method validation and verification using diverse sets of samples targeting different Canadian wheat classes and grown in three different crop years, results showed the LNT method to be more discriminating and easily adopted by other laboratories. In 2015, the LNT method was adopted as the method of choice in future Canadian variety registration trials. The LNT method is fast, simple and well-suited to high throughput test baking conditions encountered in the evaluation of large numbers of breeder lines. A new objective parameter, loaf top ratio, was also introduced and found to correlate well with dough strength and dough handling properties.  相似文献   
64.
[目的]研究黄淮海区玉米青枯病的田间自然筛选及接种鉴定。[方法]采用试验室接种鉴定及大田自然鉴定的方法,研究25份玉米自交系和61份群体材料对玉米青枯病的抗病表现。[结果]筛选出9份自交系及26份群体材料的抗病等级都在R(抗病)以上。多数种质资源的抗病性集中在3级和5级,为R(抗病)和MR(中抗)材料;未发现有9级(高感)材料。[结论]该研究为玉米青枯病在黄淮海区的防治提供技术参考。  相似文献   
65.
5种杀虫剂对粘虫不同发育阶段的室内毒力   总被引:1,自引:0,他引:1  
采用胃毒法、卵和蛹采用浸渍法,测定甲氨基阿维菌素苯甲酸盐、氯虫苯甲酰胺、辛硫磷、联苯菊酯、高效氯氟氰菊酯5种杀虫剂对粘虫卵、1龄幼虫、3龄幼虫、5龄幼虫和蛹的室内毒杀作用。结果表明:供试5种杀虫剂对卵的触杀作用依次为甲氨基阿维菌素苯甲酸盐高效氯氟氰菊酯联苯菊酯辛硫磷氯虫苯甲酰胺;对幼虫的毒杀作用依次为甲氨基阿维菌素苯甲酸盐联苯菊酯、高效氯氟氰菊酯氯虫苯甲酰胺辛硫磷;对蛹的触杀作用依次为高效氯氟氰菊酯联苯菊酯辛硫磷甲氨基阿维菌素苯甲酸盐氯虫苯甲酰胺。甲氨基阿维菌素苯甲酸盐对粘虫卵和幼虫的毒杀效果最好,对卵、1龄幼虫、3龄幼虫、5龄幼虫的LC50分别为0.276、1.555、0.109和1.483 mg/L;高效氯氟氰菊酯对粘虫蛹的触杀效果最好,LC50为5.539mg/L。建议根据粘虫发生的实际情况,在生产中将甲维盐和高效氯氟氰菊酯作为防治粘虫的首选药剂。与其他供试的4种杀虫剂相比,氯虫苯甲酰胺对粘虫卵和蛹的毒杀作用最弱,对1龄、3龄、5龄幼虫的毒杀作用略高于辛硫磷或与其相当,显著低于联苯菊酯、高效氯氟氰菊酯和甲氨基阿维菌素苯甲酸盐,建议在粘虫大发生时慎用。  相似文献   
66.

Background

Despite being the most commonly used mammal in biomedical research, problems with perinatal mortality in mice have received little attention and the causes of pup death are still poorly known. Females are often housed alone with their litters and since the lost pups are generally eaten, it is commonly assumed that the mother has killed them. However, more detailed observations than have been reported previously in the literature are required to establish if the cause of death is infanticide. Litter loss can only be prevented efficiently after underlying causes have been carefully investigated and interpreted. The aim of this study was to investigate if females actively kill their pups by observing the behaviour of females and pups in litters that later were lost. We used video recordings of females that lost their entire litter to observe females in detail from parturition until the pups died. In total, 10 C57BL/6 females (wildtype and the knockouts Hfe−/− and β2m−/−) were studied, housed in Makrolon II cages with or without access to a small amount of nesting material.

Results

Three of the females had pups that were never seen moving, and another three females had one or two pups that never moved, indicating that some pups were most likely still-born. In five females with live-born pups, detailed observations from the time when a pup was last seen moving until it died were possible to carry out. We observed females eating dead offspring and interacting with both moving and dead pups. However, we never observed a pup stop moving when manipulated by the female, nor were any wounds seen in the pups. Hence, we found no evidence of infanticide when studying females that had lost their entire litter.

Conclusion

These results suggest that other causes than infanticide plays a major role in mouse pup death, and stress the need for more systematic and careful investigations of the causality of litter loss.  相似文献   
67.
随着高职院校办学规模的扩大,学生人数的增加,实验室产生的废弃物越来越多,若处理不当将引起二次传染和环境污染,危害人们身体健康。加强对农类高职院校实验室废弃物分类、危害的认识和重视,并对实验室废弃物进行科学处理,有利于疾病的预防与控制、实验室建设和环境保护。  相似文献   
68.
Birch leaves and horse manure were used to determine the effects of food quality on growth and reproduction of laboratory-reared Lumbricus terrestris. Animals grew to maturity within 6 months but attained a significantly (p < 0.001) larger adult size with manure (6.17 g) versus leaves (4.20 g). Cocoon production by recently-mated adults maintained in isolation, fed with birch leaves or horse manure, resulted in 4.53 and 3.84 cocoons ind.−1 month−1 respectively, with an initial hatchability of 86%, falling to zero after 18 months. Re-mating of these known individuals permitted long term monitoring of reproductive output (to 30 months). For the whole experimental period, overall hatchability of the 2010 cocoons produced was 44.4%. Median incubation time of those cocoons that hatched within accepted norms (less than 5 months at 15 °C) was 103 days and was not influenced by adult food type. A proportion (35.5%) of cocoons took in excess of 12 months to hatch. Adult mortality was minimal (25%) during the long term experiment but abnormal cocoon production was recorded after 2 years. Overall results demonstrate that food quality can have a significant influence on somatic and reproductive production of L. terrestris and these data may aid construction of production models for this earthworm in ecosystems with contrasting food quality.  相似文献   
69.
韦巍 《计算机与农业》2008,(12):111-112
高校实验室管理信息系统能够减轻实验室管理人员的负担,提高管理效率和服务水平。本文主要介绍当前高校实验室管理信息系统的三种开发模式(C/S模式,B/S模式,混合模式),详细分析了它们的优缺点,并列举了应用实例.  相似文献   
70.
This laboratory-based study provides baseline life cycle data for the obligatory parthenogenetic earthworm Octolasion cyaneum. Singleton and twin hatchlings were cultured individually with biomass, survival and reproductive condition recorded at 4-weekly intervals during a complete year. After maturation, cocoon production, masses and incubation time were also recorded along with viability and number of hatchlings per cocoon. Individual mean mass of singletons was significantly (P < 0.05) greater than twins at the outset (0.042 and 0.025 g respectively) and remained so until week 52 (2.22 and 1.96 g respectively). Singletons matured more rapidly than twins (24 vs. 32 weeks respectively) and produced more cocoons than twins (3.2 and 2.2 coc worm−1 (4 weeks)−1 respectively). Approximately 20% of all viable cocoons produced twins. Singleton hatchlings weighed significantly (P < 0.05) more than twin hatchlings (0.032 and 0.018 g respectively) but there was no significant difference (P > 0.05) between mean masses of singleton (mean masses 0.033 and 0.032 g) or twin (0.017 and 0.018 g) hatchlings produced by singleton and twin parents. The likelihood that a cocoon contained twins or a singleton was not influenced by the singleton/twin status of the parent. There was no significant difference (P > 0.05) in the incubation times of cocoons produced by singletons and twins (129 and 128 days respectively).  相似文献   
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