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151.
Ricardo de la Fuente Jesus Almazan Esperanza Gomez-Lucia Jean Freney Guillermo Suarez 《Comparative immunology, microbiology and infectious diseases》1986,9(4):347-353
A total of 176 Gram-positive, catalase positive cocci strains, isolated from sheep were studied by different routine tests for the differentiation of staphylococci and micrococci, comparing their validity and usefulness. By glucose fermentation and growth in the anaerobic portion of thioglycolate 85 and 73.6% respectively of coagulase negative staphylococci were misclassified as Micrococcus spp. Susceptibility to lysostaphin was an adequate test for the differentiation of the strains. Atypical results in the production of acid from glycerol/erythromycin were obtained in 11.8% of the coagulase negative strains and 16.7% of micrococci. The combined use of the selective media furazolidone agar and Schleifer and Krämer medium resulted in a fast and useful separation of ovine staphylococci and micrococci. The bacteriolytic activity misclassified 32.2% of the coagulase negative strains. 相似文献
152.
Gastrointestinal Lymphoma in 20 Dogs 总被引:1,自引:1,他引:0
C. Guillermo Couto DVM H. Carolien Rutgers DVM MS Robert G. Sherding DVM Jennifer Rojko DVM PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1989,3(2):73-78
The records of 20 dogs with histopathologically diagnosed gastrointestinal (GI) lymphoma (LSA) evaluated between 1970 and 1984 were reviewed. Fifteen dogs were considered to have primary GI LSA, while five dogs had GI involvement in association with the multicentric form. Most clinical and laboratory findings were nonspecific, but positive-contrast upper GI radiography was suggestive of GI LSA in all of the dogs evaluated. Nine dogs had extensive lymphocytic-plasmacytic inflammatory infiltrates around the neoplastic foci, resulting in difficulty in obtaining a diagnosis of GI LSA when samples were obtained by endoscopy. 相似文献
153.
Cutaneous Hemangiosarcoma in 25 Dogs: A Retrospective Study 总被引:2,自引:1,他引:1
Heidi Ward Leslie E. Fox Maron B. Calderwood-Mays Alan S. Hammer C. Guillermo Couto DVM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1994,8(5):345-348
Hemangiosarcomas confined to the skin and underlying muscle were surgically excised in 25 dogs. Tumors were staged based on their histological location (ie, dermal, hypodermal, and deep). Dermal (stage I) hemangiosarcomas were small, most commonly ventral-abdominal or preputial in location, and were associated with prolonged survival times (median survival, 780 days). Tumors with hypodermal (stage II) and underlying muscular involvement (stage III) were grouped together because of their larger size, bruise-like appearance, lack of anatomic predilection, biological behavior, and shorter survival times (median survival of 172 and 307 days for dogs with stages II and III, respectively). We conclude that dermal hemangiosarcomas may be effectively treated with surgery alone, whereas hemangiosarcomas located within the hypodermal tissues bear a poor prognosis and warrant wide surgical excision with adjuvant chemotherapy. 相似文献
154.
Lord LK Yaissle JE Marin L Couto CG 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(6):1243-1250
BACKGROUND: Adoption of retired racing Greyhounds has become increasingly popular during the past decade. To date, research has focused on the physiologic and clinicopathologic peculiarities of Greyhounds but there is little published information on disease prevalence in the breed. OBJECTIVE: The objective of this study is to determine the prevalence of disease in retired racing Greyhounds. ANIMALS: In this study, 747 Greyhounds were used. METHODS: A standardized survey method was used, and survey responses were collected by an Internet survey. Owners could answer a survey for every Greyhound that they had owned since January 1, 2005. RESULTS: Of the 692 eligible participants, 441 (63.7% response rate) completed surveys for 747 Greyhounds. The mortality rate for Greyhounds within the 2-year period was 15% (113 of 747 died). The most common cause of death reported was cancer (66 dogs, 58%), and the most common type of cancer listed as the cause of death was osteosarcoma (28 dogs, 25%). The most commonly reported groups of diseases or disorders were skeletal (232 dogs, 33%), skin (197 dogs, 28%), digestive (132 dogs, 18%), cancer (94 dogs, 13%), and endocrine (85 dogs, 11.9%). Forty-five percent of Greyhounds diagnosed with cancer and 6% of the overall population had osteosarcoma. CONCLUSIONS AND CLINICAL IMPORTANCE: The results of this study can be used by veterinary researchers to continue to investigate the most common diseases in this population. As more retired racing Greyhounds enter the pet population, the results of this study will help educate veterinarians and owners about the most prevalent diseases in the breed. 相似文献
155.
156.
Huertas Herrera Alejandro Promis Álvaro Toro-Manríquez Mónica Lencinas María Vanessa Martínez Pastur Guillermo Río Matías 《New Forests》2022,53(3):469-485
New Forests - In forests affected by heavy fires and continuous grazing of exotic herbivorous mammal species, Nothofagus pumilio (lenga) cannot recover naturally. The main factors that hinder the... 相似文献
157.
Martínez Pastur Guillermo José Cellini Juan M. Chaves Jimena E. Rodríguez-Souilla Julián Benitez Julieta Rosas Yamina M. Soler Rosina M. Lencinas María V. Peri Pablo L. 《Agroforestry Systems》2022,96(7):1039-1052
Agroforestry Systems - Sustainable forest management is proposed as a solution for many ecological and socio-economic trade-offs associated with different forest uses. In Patagonia, silvopastoral... 相似文献
158.
Use-dependent forms of synaptic plasticity have been extensively characterized at chemical synapses, but a relationship between natural activity and strength at electrical synapses remains elusive. The thalamic reticular nucleus (TRN), a brain area rich in gap-junctional (electrical) synapses, regulates cortical attention to the sensory surround and participates in shifts between arousal states; plasticity of electrical synapses may be a key mechanism underlying these processes. We observed long-term depression resulting from coordinated burst firing in pairs of coupled TRN neurons. Changes in gap-junctional communication were asymmetrical, indicating that regulation of connectivity depends on the direction of use. Modification of electrical synapses resulting from activity in coupled neurons is likely to be a widespread and powerful mechanism for dynamic reorganization of electrically coupled neuronal networks. 相似文献
159.
Lopez MG Mancilla-Margalli NA Mendoza-Diaz G 《Journal of agricultural and food chemistry》2003,51(27):7835-7840
Agave plants utilize crassulacean acid metabolism (CAM) for CO(2) fixation. Fructans are the principal photosynthetic products generated by agave plants. These carbohydrates are fructose-bound polymers frequently with a single glucose moiety. Agave tequilana Weber var. azul is an economically important CAM species not only because it is the sole plant allowed for tequila production but because it is a potential source of prebiotics. Because of the large amounts of carbohydrates in A. tequilana, in this study the molecular structures of its fructans were determined by fructan derivatization for linkage analysis coupled with gas chromatography-mass spectrometry (GC-MS), nuclear magnetic resonance (NMR), and matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF-MS). Fructans were extracted from 8-year-old A. tequilana plants. The linkage types present in fructans from A. tequilana were determined by permethylation followed by reductive cleavage, acetylation, and finally GC-MS analysis. Analysis of the degree of polymerization (DP) estimated by (1)H NMR integration and (13)C NMR and confirmed by MALDI-TOF-MS showed a wide DP ranging from 3 to 29 units. All of the analyses performed demonstrated that fructans from A. tequilana consist of a complex mixture of fructooligosaccharides containing principally beta(2 --> 1) linkages, but also beta(2 --> 6) and branch moieties were observed. Finally, it can be stated that fructans from A. tequilana Weber var. azul are not an inulin type as previously thought. 相似文献
160.
Bertin Yao Kouadio Jeffrey O. Dawson Guillermo A. Mendoza 《Journal of Sustainable Forestry》2013,32(6):397-416
ABSTRACTWe provide evidence that a factor contributing to the specific patterns of deforestation in Côte d’Ivoire is the set of spatial units of management used to structure wood extraction. Timber harvests were organized through a system of harvest perimeters, called “chantier,” for nearly a century. Chantiers were initiated as managerial instruments. However, their use as spatial tool for profit maximization led to positional anarchy. The lack of support for sustainable harvests from the legislation, the restoration system, and the tree-based policy governing the use of their content made the chantier the basis of a one-way resources extraction. Managerial scales facilitated clearing of forests. None served to regenerate forests. Using historical and official documents, satellite and cartographic data, we attempted to demonstrate how managerial scales aiming to organize logging have contributed to deforestation. We discuss the phases of fragmentation in the rainforest, the managerial scales, and the environmental context in which they were applied. We summarize the legislation that governed the managerial scales and how these scales organized space but the tree species-based policies and activities resulted in the forest’s dilapidation. The final section addresses the use of these scales in the creation of data for policy making. 相似文献