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571.
Behr L Chetboul V Sampedrano CC Vassiliki G Pouchelon JL Laborde F Borenstein N 《Veterinary surgery : VS》2007,36(3):190-198
OBJECTIVES: To describe an open, beating heart surgical technique and use of a bovine pericardial prosthetic valve for mitral valve replacement (MVR) in the dog. STUDY DESIGN: Clinical case report. ANIMALS: Male Bull Terrier (17-month-old, 26 kg) with mitral valve dysplasia and severe regurgitation. METHODS: A bovine pericardial bioprosthesis was used to replace the mitral valve using an open beating heart surgical technique and cardiopulmonary bypass. RESULTS: Successful MVR was achieved using a beating heart technique. Mitral regurgitation resolved and cardiac performances improved (left ventricular end-diastolic diameter decreased from 57.6 to 48.7 mm, and left atrium/aorta ratio returned to almost normal, from 1.62 to 1.19). Cardiopulmonary by-pass time and total surgical duration were decreased compared with standard cardioplegic techniques. Surgical recovery was uneventful and on echocardiography 6 months later valve function was excellent. CONCLUSION: Considering the technique advantages (no cardiac arrest, ischemic reperfusion injury, and hypothermia, or the need for aortic dissection and cannulation for administration of cardioplegic solution), short-term mortality and morbidity may be reduced compared with standard cardioplegic techniques. CLINICAL RELEVANCE: Based on experience in this dog, beating heart mitral valvular replacement is a seemingly safe and viable option for the dog and bovine pericardial prosthesis may provide better long-term survival than mechanical prostheses. 相似文献
572.
Fabiola G. Valenzuela Que Gilberto Villanueva-López Alejandro Alcudia-Aguilar Ojilve Ramón Medrano-Pérez Luisa Cámara-Cabrales Pablo Martínez-Zurimendi Fernando Casanova-Lugo Deb Raj Aryal 《Soil Use and Management》2022,38(2):1237-1249
Silvopastoral systems have great potential for storing carbon because of carbon assimilation in tree woody biomass, carbon input through litterfall and below-ground carbon turnover. In this study, we quantified and compared the carbon stocks at livestock ranches in Tabasco, Mexico, containing either scattered trees in grazing pastures (STP) or grass monocultures. Sampling plots were randomly established at each ranch where the above- and below-ground carbon stocks, carbon input from litterfall, grass production and arboreal biomass growth were measured. We found that silvopastoral systems stored an average of 257.45 Mg ha−1 of soil organic carbon (SOC) compared to 119.17 Mg SOC ha−1 at grass monoculture ranches (to 30 cm depth); silvopastoral systems also stored 44.64 Mg C ha−1 in wood biomass; and, grass monocultures had greater cumulative grass biomass production. Overall, it is concluded that livestock ranches in Tabasco, Mexico, with scattered trees in grazing pastures stored 58.8% more carbon than those grass monocultures, with carbon stocks of 327.01 Mg C ha−1and 134.47 Mg C ha−1, respectively. The results are useful for land management decision making for sustainable livestock systems framed in the Sustainable Development Goals (SDGs). 相似文献