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排序方式: 共有123条查询结果,搜索用时 15 毫秒
81.
为验证磺胺嘧啶原料药生产设备清洁方法的有效性,从验证合格标准、取样回收率、检测方法、设备清洁后的贮存期限等方面对清洁方法进行了研究。试验证明,磺胺嘧啶原料药生产设备的清洁方法是有效的,按此方法清洁的设备其贮存期限为14天。  相似文献   
82.
One hundred veterinarians and 100 breeders of traditionally docked dogs from Queensland were surveyed by telephone to determine their attitudes towards tail docking. Eighty-four percent of the breeders surveyed were in favour of docking, whereas 83% of veterinarians were opposed to the practice. Most pups were docked between 1 and 3 days of age. All veterinarians surgically amputated the tail, whereas 16% of breeders applied rubber bands to the tail. Seventy-six percent of the veterinarians, but only 18% of the breeders believed that docking caused significant to severe pain. No veterinarians, but 25% of the dog breeders believed that docking was painless. Although recent changes to the Queensland Canine Control Council's rulings allow dogs with intact tails to be shown in traditionally docked classes, the requirement of breed standard was cited as the major reason for tail docking by both breeders and veterinarians.  相似文献   
83.
This article provides a comparative analysis of factors influencing the out-of-state export decisions of establishments within selected groups of services-producing and manufacturing industries. Data were gathered through a mail survey of establishments located in both rural and urban areas of five Midwestern states. The proportion of sales exported was specified as a function of establishment and location characteristics and estimated using Tobit analysis. Results of the study indicate that both establishment and location characteristics are important predictors of the export decision and confirm that establishments in some services-producing industries are able to enter and compete in out-of-state export markets. Similar factors were found to influence the export decisions of services-producing and manufacturing establishments. Results suggest that services-producing establishments in the group of industries may not be footloose with respect to locational choices.  相似文献   
84.
In southern Australia, cattle at risk from selenium (Se) deficiency can be given an oral dose of supplements that are effective in maintaining adequate Se status for between 9 and 12 months. The present study was undertaken to assess the duration of the effect of parenteral barium selenate (BaSe) in raising the Se status of cattle at pasture in an area of marginal Se deficiency. The BaSe was given subcutaneously to Hereford heifers, using an 18-gauge needle. Cattle had regular blood sampling to assay Se, from 8 days before dosing to 1155 days afterwards. Results show that a single injection of BaSe was effective in elevating blood and plasma Se concentrations to normal values for at least 2 to 3 years, when given to beef cattle of low normal Se status. We suggest that a prophylactic dosage of 0.5 mg Se/kg body weight as BaSe should be given every 2 years to prevent Se inadequacy in beef cattle grazing pasture of marginal Se content.  相似文献   
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Bovine Neonatal Pancytopenia (BNP), a bleeding syndrome of neonatal calves, is caused by alloantibodies absorbed from the colostrum of particular cows. A commercial BVD vaccine is the likely source of alloantigens eliciting BNP associated alloantibodies. We hypothesized that the rare occurrence of BNP in calves born to vaccinated dams could be associated with genetic differences within dams and calves. We found that the development of BNP within calves was a heritable trait for dams, not for calves and had a high heritability of 19%. To elucidate which genes play a role in the development of BNP we sequenced candidate genes and characterized BNP alloantibodies. Alloantigens present in the vaccine have to be presented to the dam’s immune system via MHC class II, however sequencing of DRB3 showed no differences in MHC class II haplotype between BNP and non-BNP dams. MHC class I, a highly polymorphic alloantigen, is an important target of BNP alloantibodies. Using a novel sequence based MHC class I typing method, we found no association of BNP with MHC class I haplotype distribution in dams or calves. Alloantibodies were detected in both vaccinated BNP and non-BNP dams and we found no differences in alloantibody characteristics between these groups, but alloantibody levels were significantly higher in BNP dams. We concluded that the development of BNP in calves is a heritable trait of the dam rather than the calf and genetic differences between BNP and non-BNP dams are likely due to genes controlling the quantitative alloantibody response following vaccination.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-014-0129-0) contains supplementary material, which is available to authorized users.  相似文献   
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Sclerotinia sclerotiorum on linseed   总被引:1,自引:1,他引:0  
  相似文献   
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