怎样控制乳房炎致病菌     

Sear.  PM 王春明 《乳业科学与技术》1993,(1):17-20

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鸡传染性贫血病的研究进展(综述)     

张晓根  汪德刚  王春明 《郑州牧业工程高等专科学校学报》1994,(2)

鸡传染性贫血病(Chicken IfectiousAnaemin—CIA)是由鸡贫血因子引起的一种以雏鸡再生障碍性贫血和淋巴组织萎缩为特征的免疫抑制型疾病.由于患病鸡免疫系统遭到破坏,致使其极易继发其它病毒、细菌及真菌感染,死亡率增高.  相似文献   

Cavitation and the interaction between macroscopic hydrophobic surfaces     

Christenson HK  Claesson PM 《Science (New York, N.Y.)》1988,239(4838):390-392

The interaction in water of neutral hydrocarbon and fluorocarbon surfaces, prepared by Langmuir-Blodgett deposition of surfactant monolayers, has been investigated. The attraction between these hydrophobic surfaces can be measured at separations of 70 to 90 nanometers and thus is of considerably greater range than previously found. Spontaneous cavitation occurred as soon as the fluorocarbon surfaces were brought into contact but occurred between the hydrocarbon surfaces only after separation from contact. The very long range forces measured are a consequence of the metastability of water films between macroscopic hydrophobic surfaces. Thus the hydrophobic interaction between macroscopic surfaces may not be related to water structure in the same way that the hydrophobic effect between nonpolar molecules is related to water structure.  相似文献   

Dynamic properties of molecularly thin liquid films     

Israelachvili JN  McGuiggan PM  Homola AM 《Science (New York, N.Y.)》1988,240(4849):189-191

An experimental technique is described for simultaneously measuring the static and dynamic interactions of very thin liquid films between two surfaces as they are moved normally or laterally relative to each other. Film thickness can be measured and controlled to 1 angstrom. Initial results are presented of the transition in the physical properties of liquid films only one molecular layer thick to thicker films whose properties are practically indistinguishable from the bulk. In particular, the results show that two molecularly smooth surfaces, when close together in simple liquids, slide (shear) past each other while separated by a discrete number of molecular layers, and that the frictional force is "quantized" with the number of layers.  相似文献   

William osler and comparative medicine   总被引：2，自引：2，他引：0       下载免费PDF全文

Teigen PM 《The Canadian veterinary journal. La revue veterinaire canadienne》1984,25(10):400-405

During the last thirty years of the nineteenth century, comparative medicine deeply influenced veterinary education in Montreal, New York and Philadelphia. Of the many physicians and veterinarians involved in this movement, Sir William Osler has attracted the most biographical and historical attention. However, his contributions to comparative medicine have been characterized inexactly, partly because of his later prominence as a clinician and partly because little has been written about the history of veterinary education in Quebec.

Osler's teaching and research in comparative medicine as well as his efforts to promote a veterinary profession are described and set alongside the work of other physicians and veterinarians who were his contemporaries. As a result, Osler's contributions to comparative medicine are seen to be many and important but by no means unique. Other Quebec veterinarians, including Duncan McEachran, Orphyr Bruneau, Victor T. Daubigny and J.A. Couture, and such physicians as T. Wesley Mills and J. George Adami made as many, and in some cases greater, contributions to veterinary education in Quebec than did Osler. That they have not received the degree of recognition that Osler has received reveals Osler's ability to represent values and ideals and draws attention to some essential features of late nineteenth-century comparative medicine.

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Testing the serving capacity of beef bulls     

Packard PM 《New Zealand veterinary journal》1983,31(1-2):20

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Concepts of Ecosystem Ecology. A Comparative View. L. R. Pomeroy and J. J. Alberts, Eds. Springer-Verlag, New York, 1988. xii, 384 pp., illus. $72. Ecological Studies, vol. 67. Based on a conference     

Vitousek PM 《Science (New York, N.Y.)》1989,243(4892):825-826

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Other books of interest     

Gresshoff PM 《Science (New York, N.Y.)》1993,262(5142):2071-2072

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Mechanisms of nitrogen retention in forest ecosystems: a field experiment     

Vitousek PM  Matson PA 《Science (New York, N.Y.)》1984,225(4657):51-52

Intensive forest management led to elevated losses of nitrogen from a recently harvested loblolly pine plantation in North Carolina. Measurements of nitrogen-15 retention in the field demonstrated that microbial uptake of nitrogen during the decomposition of residual organic material was the most important process retaining nitrogen. Management practices that remove this material cause increased losses of nitrogen to aquatic ecosystems and the atmosphere.  相似文献   

Bovine ceroid-lipofuscinosis: pathology of blindness     

Jolly RD  Gibson AJ  Healy PJ  Slack PM  Birtles MJ 《New Zealand veterinary journal》1992,40(3):107-111

Five Devon cattle with suspected ceroid-lipofuscinosis and aged between 19 and 39 months of age were humanely slaughtered and subjected to post-mortem examination. There was severe atrophy of the cerebrum, particularly of the occipital cortex. Microscopy also showed severe atrophy of the retina with complete loss of photoreceptor cells, even in the youngest animal examined. Histopathologically the disease was characterised by accumulation of a fluorescent lipopigment in neurones, including those of the retina and a severe astrocytosis. The disease, which is characterised by the accumulation of subunit c of mitochondrial ATP synthase, is similar to that extensively described in South Hampshire sheep except that the retinal lesions were more severe. In contrast, tremors were not noted in the cattle. The clinical history and similarity to the disease in sheep and other species indicated inheritance was as an autosomal recessive trait.  相似文献