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1.
刘德 《农业机械》2020,(2):65-67
管理学家德鲁克指出,基于顾客,企业只有两项最基本的职能:营销和创新.在当下农机行业进入存量竞争阶段,想要跳出同质化的红海,创新和营销变得特别重要. 2019年已过去,但它留下的印记却是深刻的,尤其是在农机营销领.笔者为大家整理出过去一年农机行业有重大影响的营销事件.  相似文献   
2.
-蒎烯合成2-羟基-3-蒎酮的研究   总被引:1,自引:1,他引:0  
研究了高锰酸钾氧化α-蒎烯合成2-羟基-3-蒎酮的工艺条件,对助溶剂等影响因素进行了探讨,较优工艺条件为:以叔丁醇为助溶剂,不改变pH值,温度0-5℃,KMnO4与α-蒎烯的物质的量比为1.7:1~1.8:1,先加α-蒎烯后加KMnO4.所得2-羟基-3-蒎酮采用IR、MS、1H NMR、3C NMR进行了表征,产率达60%,与文献相同,助溶剂改用叔丁醇后回收率>90%,高于原用助溶剂丙酮(回收率70%).  相似文献   
3.
Restriction endonuclease analysis and DNA hybridization revealed five ovine strains of Mycobacterium paratuberculosis from South Africa had identical DNA patterns to an ovine strain from Canada. Genetically this strain type has features in common with the two major groups of M. paratuberculosis.  相似文献   
4.
A central axonopathy in 2 male and 1 female Scottish Terrier puppies from 3 different but related litters is reported. Clinical signs consisting of severe whole-body tremors and ataxia were first detected at the age of 10 to 12 weeks. They worsened with activity and excitement and diminished during rest or sleep. Two dogs also had paraparesis. In 1 dog the neurological deficits progressed over several months. Neuropathological examination revealed widespread axonal changes, vacuolation, and gliosis in the white matter of the central nervous system.  相似文献   
5.
鼻气管鸟杆菌发现于 1 990年 ,自那时以来已在世界范围内被公认为一种呼吸道病原菌 ,可在肉用鸡引起原发感染或继发感染。对种鸡进行免疫接种是减轻鼻气管鸟杆菌所致经济损失的有效方法。  相似文献   
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7.
The possible relationship between nutrition and fertility in dairy cows are reviewed. Study of the literature shows that opinions on the effect of the various nutrients differ markedly. The conclusion which can be made is that in countries where standards of dairy farming are high, nutrition only plays a minor role in the problem of herd subfertility. In the course of time deficiencies in a large number of minerals, trace elements and vitamins have been stressed as a cause of inadequate fertility. However cows are at present generally fed with a lot of well balanced concentrates and therefore deficiencies are very unlikely to occur. During early lactation every high producing dairy cow has a negative energy balance. In a number of cows this results in anoestrus and in a long interval from parturition to first insemination. Overfeeding during late lactation and the dry period does not adversely affect subsequent reproduction but may cause puerperal disorders. The relation between protein nutrition and fertility is complex. Protein effects on fertility are minor. Problems can arise if there is a combination of a high percentage of crude protein (greater than 18%), a high rumen degradability of the protein and a low energy content of the diet. The value of metabolic profile tests is minimal because they do not differentiate between normal herds and herds with fertility problems.  相似文献   
8.
Dehydration, to varying degrees, will inevitably occur in horses participating in endurance trail rides. This water loss is directly related to the amount of body water lost through evaporative cooling, that in turn being related to the amount and rate of work performed, and to the environmental temperature and humidity.An electronic apparatus that can substitute for the conventional and time-consuming venous haematocrit was developed to measure the animals' hydration status. The mechanism of this electrometer is based upon the relationship between the red cell content and the electrical conductivity of the blood. The electrometer reading gave a significant correlation (p<0.001) with the venous haematocrit, thus indicating that the electrometer is a reliable apparatus for determining the animals' hydration status within seconds of venepuncture.  相似文献   
9.
A total of 595 faecal samples from raptorial birds, either captive or free‐living, residing in GREFA Wildlife Hospital were bacteriologically examined using various selective media and an Automated Diagnostic Assay System for Salmonella detection. Serotype and phage type of the strains identified as Salmonella was determined. In the captive group, of the 285 samples examined, 21 (7.36%) were positive for Salmonella. Serotyping revealed that most of the individuals were infected by Salmonella serotype Havana. This result suggested that there could be a source of contamination in the Hospital although it could not be established. In the wild free‐living group, over 310 samples examined (4.19%) were positive for Salmonella. The Salmonella isolates showed a major variety of serotypes: Enteritidis, Adelaide, Brandenburg, Newport, Typhimurium, Hadar, Saintpaul and Virchow. Most of them are similar to those commonly described in isolates from human and domestic animals. These results indicate that wild birds could be involved in the dissemination of Salmonella in humans or domestic animals or vice versa.  相似文献   
10.
以关中驴为试验动物 ,用猪瘟病毒(HCV )、犬细小病毒 (CPV )、兔瘟病毒(RHDV)、鸡新城疫病毒 (NDV)、伪狂犬病毒(PRV)等病毒进行免疫 ,检测所产生的抗体效价 ,并与猪、鸡、兔、犬、及猫等动物进行比较。试验结果表明 ,关中驴与对照动物产生的抗体效价一致 ,证明了关中驴可替代其它动物用于生物制品研究  相似文献   
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