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Image magnification is inherent in radiography. In digital fluoroscopy, the three components of magnification are geometric, electronic and photographic. In this study, the total magnification factor of a digital imaging system was determined by two methods, 1) comparison of measurements of a known object to its image and 2) calculation of geometric, electronic and photographic magnification from the imaging system specifications. Both methods were employed for various focal-film distances, image intensifier tube modes and laser printer formats. Results of these two methods were different due to the detrimental effect of penumbra on image quality with increasing magnification. If a radiographic image is to be used to approximate object size, then a technique should be used that will minimize magnification. In digital fluoroscopy this is achieved with the shortest object-film distance (assuming a fixed focal-object distance), largest image intensifler mode and greatest number of images per sheet of film. 相似文献
44.
Carolina Naranjo Dolors Fondevila Marta Leiva Xavier Roura Teresa Pea 《Veterinary ophthalmology》2010,13(3):139-143
Objective Canine leishmaniosis is a disease characterized by the wide distribution of the parasite throughout the tissues of the host. The purpose of this study was to describe the presence of Leishmania spp. and associated inflammation in ocular‐associated muscles of dogs with patent leishmaniosis. Procedures Smooth muscles (iris dilator muscle, iris sphincter muscle, ciliary muscle, Müller muscle, smooth muscle of the periorbita and smooth muscle of the nictitating membrane) and striated muscles (orbicularis oculi muscle, obliquus dorsalis muscle and dorsal rectus muscle) were evaluated. Routine staining with hematoxylin and eosin and immunohistochemistry to detect Leishmania spp. were performed on tissue sections. Results Granulomatous inflammation was seen surrounding muscular fibers and was composed mainly of macrophages with scattered lymphocytes and plasma cells. This infiltrate could be seen in 52/473 (10.99%) samples of smooth muscle and 36/142 (25.35%) samples of striated muscle. Parasites were detected in 43/473 (9.09%) samples of smooth muscle and in 28/142 (19.71%) samples of striated muscle. Conclusions To the authors’ knowledge, this is the first report assessing the presence of Leishmania spp. and associated infiltrate in intraocular, extraocular and adnexal smooth and striated muscles. The inflammation present in those muscles could contribute to clinical signs already described, such as blepharitis, uveitis, and orbital cellulitis. 相似文献
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M. Arias L. Robertson A. Garcia‐Alvarez S. C. Arcos M. Escuer R. Sanz J. P. Mansilla 《Forest Pathology》2005,35(5):375-383
A survey of the xylophagous insects in the conifer forests, mainly Pinus pinaster woodlands, in Spain was carried out in order to study the phoretic vectors of nematodes of the genus Bursaphelenchus. Fifteen environmental sites were characterized on the bases of altitude, rainfall, temperature and conifer species. Specimens of Orthotomicus erosus (n = 3476) were captured of which 59% carried nematodes under their elytrous, most of them were aphelenchid fungal‐feeding nematodes, but B. fungivorus was found on the beetles from Las Cumbres, Villa Blanca, (Huelva), southern Spain, which represent the first record of O. erosus as vector of a Bursaphelenchus sp. The nematode is characterized by morphometric and biomolecular techniques and distribution and ecology of the insect is discussed. 相似文献
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Charels D Broeders S Corbisier P Trapmann S Schimmel H Linsinger T Emons H 《Journal of agricultural and food chemistry》2007,55(9):3258-3267
This paper is part of a set of three papers investigating metrological traceability of the quantification of DNA fragments as, for instance, used for quantification of genetic modifications. This paper evaluates the possible impact of several factors on results of real-time Polymerase Chain Reaction (PCR) measurements. It was found that the particle size of the powder samples does not have an influence, whereas the nature of the calibrant (plasmidic or genomic DNA) has a significant effect. Moreover, two real-time PCR detection methods (construct-specific and event-specific) for MON 810 corn were compared. The results obtained in a specifically designed interlaboratory study revealed a significant influence of the DNA extraction method on measurement results when the MON 810 construct-specific real-time PCR detection method was applied. Statistical analyses confirmed the importance of validating DNA extraction methods in conjunction with real-time PCR methods. 相似文献
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Carlos O. Schild Fabiana M. Boabaid Luiz G.S. Olivera Mizael Machado Ana Vildoza Anderson Saravia Alejandra Custodio Carolina Command Agustín Martinez Martín Jaurena Rob Dixon Franklin Riet-Correa 《Journal of veterinary diagnostic investigation》2021,33(5):1018
We investigated 2 outbreaks of osteomalacia as a result of phosphorus (P) deficiency in herds of lactating beef cows grazing subtropical native pastures in Uruguay. Cows exhibited pica, difficulty to stand and walk, rib fractures, and body weight loss even with adequate forage availability. Osteopenia and severe osteomalacia were observed on gross and histologic examination. The concentrations of bicarbonate-extractable P in soil (4.0, 4.1 mg P/kg), total P in pasture (0.9, 1.1 g P/kg), inorganic P in serum (1.0, 0.71 mmol P/L), and P in bone (73 mg P/mL) were all low. Although injectable and mineral salt supplements provided additional P in both outbreaks, these supplementary amounts were insufficient to prevent P deficiency. The P ingested by the cows from the pasture and supplements would have provided 20–55% of their daily P requirements of ~21 g P/d. Osteomalacia occurred in cattle at the 2 ranches as a result of severe P deficiency in the soil and forage, and inadequate P supplementation. Following diagnosis, control of P deficiency in beef cattle requires estimation of the amount of pasture P ingested and provision of sufficient additional supplementary P to meet the animals’ requirements. 相似文献
49.
Silva Jos Hiago C. Saldanha Alan V. Carvalho Rayana M. R. Machado Carolina F. M. Flausino Bruno F. Antonio Adilson C. Gontijo Lessando M. 《Journal of pest science》2022,95(2):723-734
Journal of Pest Science - Increasing either inter- or intraspecific plant diversity has shown the potential to engender bottom-up and top-down effects upon herbivorous pests. Nonetheless, because... 相似文献
50.
Primo Anacláudia Alves Araújo Maria Diana Melo Silva Karla da Fonseca Silva Ludmyla Araújo Pereira Graziella de Andrade Carvalho Fernandes Francisco Éden Paiva Pompeu Roberto Cláudio Fernandes Franco Natale William de Souza Henrique Antunes 《Agroforestry Systems》2021,95(8):1459-1464
Agroforestry Systems - The use of native trees in agroecosystems is a promising way to increase litter deposition and nutrient cycling and foster the recovery of degraded areas, especially in... 相似文献