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991.
Sylvie L Benestad Lars Austb? Michael A Tranulis Arild Espenes Ingrid Olsaker 《Veterinary research》2012,43(1):87
Prion diseases such as scrapie in small ruminants, bovine spongiform encephalopathy (BSE) in cattle and Creutzfeldt-Jakob disease (CJD) in man, are fatal neurodegenerative disorders. These diseases result from the accumulation of misfolded conformers of the host-encoded prion protein (PrP) in the central nervous system. To date naturally-occurring PrP free animals have not been reported. Here we describe healthy non-transgenic animals, Norwegian Dairy Goats, lacking prion protein due to a nonsense mutation early in the gene. These animals are predicted to be resistant to prion disease and will be valuable for research and for production of prion-free products. 相似文献
992.
Bartonella vinsonii subsp. berkhoffii is a recognized cause of endocarditis in dogs and human patients and has been associated with cardiac arrhythmias, myocarditis, granulomatous lymphadenitis, polyarthritis, and granulomatous rhinitis in dogs. Little is known regarding the mode of transmission or cellular localization of this bacteria following infection of a canine host. The aim of the current study was to determine whether erythrocytes may serve as a site of infection by B. vinsonii subsp. berkhoffii. In the study, we successfully demonstrate the invasion of canine erythrocytes by a B. vinsonii subsp. berkhoffii genotype III strain using an in vitro model system. Dog erythrocytes were incubated with B. vinsonii subsp. berkhoffii after which tubes were treated with gentamicin at 12, 24, and 48 h post-inoculation. After gentamicin elimination of extracellular bacteria, there was a gradual increase in intra-erythrocytic bacteria, as assessed by colony forming units per ml, at each collection time point. The largest recovery of intracellular bacteria occurred at 48 h post-infection. These results suggest that canine erythrocytes may serve in the maintenance of bacteremia due to B. vinsonii subsp. berkhoffii within an infected host. 相似文献
993.
The suspensory ligament is difficult to image accurately, partly because it contains ligamentous fibers, as well as noncollagenous adipose and muscle tissue in the normal horse. Our hypothesis was that magnetic resonance (MR) imaging would be more accurate than ultrasonography in identifying the size of the suspensory ligament and the presence and size of noncollagenous tissues within the ligament. Eleven horses were used for ultrasonographic and MR imaging and histologic evaluation of the rear suspensory ligament. The origin and body of the normal suspensory ligament had a heterogenous appearance on MR images with two separate islands of mixed signal intensity evident throughout its otherwise hypointense cross-sectional area. Histologically, there were isolated islands of muscle, adipose, loose connective tissue and dense collagenous partitions, organized in two separate bundles that extended through the full length of the suspensory ligament origin and body to the level of its bifurcation. Comparison of MR images with corresponding histologic sections confirmed that islands of heterogenous signal intensity in normal suspensory ligaments correlated well with these bundles. Using ultrasonography, it was impossible to distinguish these islands from surrounding dense collagenous tissue consistently. MR imaging determined the cross-sectional area of the suspensory ligament more accurately than ultrasonography. Based upon these results, MR imaging is superior to ultrasonography for assessment of the suspensory ligament. The appearance associated with normal ligament anatomy needs to be understood before MR signal variation can be considered as indicative of disease in the suspensory ligament. 相似文献
994.
The future of radiography will be digital. In exotic pet radiography, where some of the animals have a very low body weight and anatomic structures can be small, detail rendition plays an important feature in image quality. Veterinarians should be familiar with the technical principles, image quality criteria, and radiation exposure issues associated with the various types of digital systems currently available. This article discusses basic principles of digital radiography, technical solutions, and selected parameters characterizing detectors, processing, and monitors. An overview of reported experiences is given, and results from experimental clinical studies are reviewed to evaluate the current options and limitations in applying digital radiography to exotic pet medicine. 相似文献
995.
ABSTRACT: Genetic resources available for Arabidopsis thaliana make this species particularly attractive as a model for molecular genetic studies of guard cell homeostasis, transport and signalling, but this facility is not matched by accessible tools for quantitative analysis of transport in the intact cell. We have developed a reliable set of procedures for voltage clamp analysis of guard cells from Arabidopsis leaves. These procedures greatly simplify electrophysiological recordings, extending the duration of measurements and scope for analysis of the predominant K+ and anion channels to that achieved previously in work with Vicia and tobacco guard cells. 相似文献
996.
Michael L Westendorf James E Wohlt 《Veterinary Clinics of North America: Food Animal Practice》2002,18(2):233-252
Brewers grains, a by-product of beer production, are often used as a livestock feed. Because brewers grains provide protein, fiber, and energy, they can be useful in a variety of diets. Protein in brewers grains can meet a significant portion of supplemental protein requirements; in addition, they provide fiber and needed bulk in the diets of ruminants and horses. Brewers grains and other brewers by-products have also been fed to pigs, sheep, and poultry. Currently, the primary market for wet brewers grains is as a dairy cattle feed; however, some may be fed to beef cattle in feedlots. Brewers grains have historically been marketed wet or dry, but wet brewers grains currently make up the majority of the marketed product. Brewers grains provide protein, energy, and fiber in livestock diets, but product variability can influence their utilization and necessitate a testing program to determine nutrient content. 相似文献
997.
Michael P. Jones 《Journal of Exotic Pet Medicine》2013,22(4):348-357
In birds of prey, vascular disease can be caused by a number of infectious or noninfectious agents and is in all likelihood underdiagnosed. This review attempts to provide a discussion of the available literature regarding vascular diseases in raptors by describing a number of conditions or etiological agents (e.g., atherosclerosis, aneurysms, bacterial and septicemic conditions, thromboembolic disease, and viral, fungal, parasitic, and miscellaneous diseases) and the vascular pathology that may occur with each. 相似文献
998.
Michael Walsh 《绿色中国(A版)》2013,(3):14-15
最近,在恶劣的天气条件下,北京和中、东部地区很多城市都经历了严重的空气污染。数个空气质量监测点都出现PM2.5爆表的情况。这种前所未有的严重污染引发了国内外媒体的广泛关注和报道,很多市民也纷纷通过微博表 相似文献
999.
1000.
Stefan Patzold Franz Michael Mertens Ludger Bornemann Britta Koleczek Jonas Franke Hannes Feilhauer Gerhard Welp 《Precision Agriculture》2008,9(6):367-390
Crop protection seldom takes into account soil heterogeneity at the field scale. Yet, variable site characteristics affect
the incidence of pests as well as the efficacy and fate of pesticides in soil. This article reviews crucial starting points
for incorporating soil information into precision crop protection (PCP). At present, the lack of adequate field maps is a
major drawback. Conventional soil analyses are too expensive to capture soil heterogeneity at the field scale with the required
spatial resolution. Therefore, we discuss alternative procedures exemplified by our own results concerning (i) minimally and
non-invasive sensor techniques for the estimation of soil properties, (ii) the evidence of soil heterogeneity with respect
to PCP, and (iii) current possibilities for incorporation of high resolution soil information into crop protection decisions.
Soil organic carbon (SOC) and soil texture are extremely interesting for PCP. Their determination with minimally invasive
techniques requires the sampling of soils, because the sensors must be used in the laboratory. However, this technique delivers
precise information at low cost. We accurately determined SOC in the near-infrared. In the mid-infrared, texture and lime
content were also exactly quantified. Non-invasive sensors require less effort. The airborne HyMap sensor was suitable for
the detection of variability in SOC at high resolution, thus promising further progress regarding SOC data acquisition from
bare soil. The apparent electrical conductivity as measured by an EM38 sensor was shown to be a suitable proxy for soil texture
and layering. A survey of arable fields near Bonn (Germany) revealed widespread within-field heterogeneity of texture-related
ECa, SOC and other characteristics. Maps of herbicide sorption and application rate were derived from sensor data, showing
that optimal herbicide dosage is strongly governed by soil variability. A phytoassay with isoproturon confirmed the reliability
of spatially varied herbicide application rates. Mapping areas with an enhanced leaching risk within fields allows them to
be kept free of pesticides with related regulatory restrictions. We conclude that the use of information on soil heterogeneity
within the concept of PCP is beneficial, both economically and ecologically. 相似文献