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101.
In Europe, rural landscapes are characterized by the presence of hedgerows and networks. In recent decades changes in agricultural systems, due in particular to the intensification of agricultural practices, have caused a transformation of hedgerows and networks, thereby reducing their qualities and changing their ecological and social functions. Yet, no global framework to analyze and design hedgerows and networks is available. Our paper is a step forward in combining the ecological and social dimension of hedgerows and hedgerow networks for both analytical and planning purposes. We propose to use a landscape grammar for deciphering the structural and functional aspects of hedgerow units and networks and to formalize rules for design and management based on scientific evidence. In the case of hedgerows, landscape grammar consists of letters, or single units of trees and shrubs of different species and their different shapes related to management practices. Appropriate or meaningful combinations of letters create words and sentences, hence forming hedgerow networks. In order to test the suitability of the grammar for reading or understanding and consequently writing or planning hedgerows in different landscapes, two study areas were chosen: Pleine-Fougères in Brittany (France) and Pianura Padana in Piedmont (Italy). The basic units, the aggregated units and the network were analyzed respectively as the letters, the words and the syntax of our landscape grammar. This metaphor provides an analytical framework for understanding hedgerows, from the individual tree to the landscape. Our model anticipates the concerns of both researchers and policymakers throughout the hedgerow network planning process. 相似文献
102.
Serum creatine kinase isoenzymes and macroenzymes in dogs with different neurologic diseases 
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下载免费PDF全文 103.
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Morandi F Mattoon JS Lakritz J Turk JR Wisner ER 《American journal of veterinary research》2003,64(7):935-944
OBJECTIVE: To develop protocols for helical computed tomography (CT) and axial high-resolution CT (HRCT) of lungs and correlate densitometric CT values with morphometric and histologic data for normal pulmonary tissue in dogs. ANIMALS: 8 healthy adult dogs. PROCEDURE: 2 dogs were used to establish a protocol for helical CT and HRCT of lungs. Six dogs were used to acquire densitometric CT data regarding normal lungs. After the dogs were euthanatized, their lungs were fixed and sampled for morphometric and histologic evaluation. Four CT acquisitions were compared by means of paired t tests. RESULTS: For normal lung tissue of dogs, mean densitometric CT value obtained during helical CT scans reconstructed in a sharp algorithm was -846 Hounsfield units. Values obtained via helical CT or HRCT acquisitions and reconstructed with sharp or standard algorithms did not differ significantly. Morphometric analysis was used to determine the proportion of lung parenchymal (82%) and non-parenchymal tissue (18%). Alveolar size, estimated by mean linear intercept, was approximately 172 microm, and alveolar surface area-to-volume ratio was 0.024 to 0.026 microm(-1). Histologic evaluation confirmed the presence of normal lung tissue. CONCLUSIONS AND CLINICAL RELEVANCE: Correlation of densitometric CT data with morphometric and histologic findings and the establishment of helical CT and HRCT protocols were attained; clinical use of this information may facilitate investigation of pulmonary disease in dogs. Sharp helical CT acquisitions were preferred because of better lung parenchyma detail and rapid image acquisitions, compared with HRCT. 相似文献
107.
Masserdotti C Ubbiali FA 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2002,31(1):22-25
Background — Fine needle aspiration cytology is being used for the diagnosis of various neoplasms, but we are unaware of reports dealing with the cytologic features of canine pilomatricoma.
Objective — The purpose of this report was to describe the cytologic features of pilomatricoma in 3 dogs.
Methods — Fine-needle aspirates were obtained from cutaneous masses using a 25-ga needle. Smears were prepared and stained with May-Grünwald-Giemsa and hematoxylin and eosin. The cutaneous masses were excised and routinely processed for histologic examination.
Results — Cytologic features of all 3 tumors included high cellularity and numerous clusters of tightly arranged of basaloid cells with evenly distributed chromatin and small distinct nucleoli surrounding sheets of "ghost cells". Ghost cells were characterized by a central unstained zone corresponding to the site previously occupied by the nucleus. Amorphous keratinized material was observed in 1 tumor. Histopathologic findings confirmed the diagnosis of pilomatricoma in all 3 cases.
Conclusions — Basaloid cells in association with ghost cells are important cytopathologic criteria that may provide a definitive cytologic diagnosis of pilomatricoma in dogs, and may help avoid a false diagnosis of malignancy. 相似文献
Objective — The purpose of this report was to describe the cytologic features of pilomatricoma in 3 dogs.
Methods — Fine-needle aspirates were obtained from cutaneous masses using a 25-ga needle. Smears were prepared and stained with May-Grünwald-Giemsa and hematoxylin and eosin. The cutaneous masses were excised and routinely processed for histologic examination.
Results — Cytologic features of all 3 tumors included high cellularity and numerous clusters of tightly arranged of basaloid cells with evenly distributed chromatin and small distinct nucleoli surrounding sheets of "ghost cells". Ghost cells were characterized by a central unstained zone corresponding to the site previously occupied by the nucleus. Amorphous keratinized material was observed in 1 tumor. Histopathologic findings confirmed the diagnosis of pilomatricoma in all 3 cases.
Conclusions — Basaloid cells in association with ghost cells are important cytopathologic criteria that may provide a definitive cytologic diagnosis of pilomatricoma in dogs, and may help avoid a false diagnosis of malignancy. 相似文献
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Martini Mina Altomonte Iolanda Sommer Matteo Federico Gili Claudia Biancani Barbara Licitra Rosario Salari Federica 《Veterinary research communications》2022,46(2):577-583
Veterinary Research Communications - Research data on milk composition in cetaceans are scattered and fragmentary. This paper analyses the gross and mineral composition, the fatty acids profile and... 相似文献
110.
The possibility of using the Iosipescu shear test device to study the combined shear and compression behavior of anisotropic materials was examined. Measurements were made using both an original (Wyoming version) and an in-house modified Iosipescu shear and compression fixture. Numerical simulation of the combined shear and compression test was carried out to verify the reliability of the modified device. The numerical results were compared with data from experiments on a medium-density fiberboard. The numerical results show good agreement with the experimental results for the shear test in all the three material directions tested. The shapes as well as the values of the strain fields were similar in the numerical and experimental results. Different rotations of the combined shear and compression device were studied using the finite element method to find the combinations that gave reliable results in shear and compression. It was found that the 45° rotation gave the most uniform strain fields in the section between the notches. This rotation was tested on the fiberboard. 相似文献