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排序方式: 共有211条查询结果,搜索用时 15 毫秒
1.
Alexander Jarryd Ehlers Smith David A. Ehlers Smith Yvette C. Downs Colleen T. 《Landscape Ecology》2019,34(3):537-549
Landscape Ecology - The effects of changing land use, and especially urbanisation, on species and functional diversity are of global concern. Eco-estates are a form of urban housing development... 相似文献
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Objectives
To report our experience with thoracoscopic lung lobectomy in dogs with primary lung tumors and compare the long‐term outcome between dogs with primary lung tumors treated with lobectomy via thoracoscopy or thoracotomy.Study Design
Retrospective case series; case–control study.Animals
Thirteen dogs with primary lung tumors treated with thoracoscopic lung lobectomy; case‐matched cohort of 9 dogs with primary lung tumors treated with lobectomy via thoracotomy.Methods
Medical records from dogs that underwent thoracoscopic lung lobectomy at a single institution were reviewed. Only cases with primary lung tumors were included. Surgical complications and conversion rate were reported. Cases without conversion and with clean margins on histologic examination were matched on prognostic criteria to cases with primary lung tumors treated with lobectomy via thoracotomy. Survival was compared between thoracoscopy and thoracotomy.Results
Thirteen dogs with primary lung tumors that measured 2.2–7 cm underwent thoracoscopic lung lobectomy. Nine dogs were diagnosed with carcinoma and 4 with histiocytic sarcoma. There were 3 conversions to open thoracotomy because of poor visualization. There were no differences in short‐term outcome between dogs that had their procedures completed via thoracoscopy and those that were converted to thoracotomy. Nine dogs with clean margins were matched with 9 dogs treated via thoracotomy. Mean (standard deviation) followup was 367 (327) days for dogs undergoing thoracoscopy and 603 (612) days for dogs undergoing thoracotomy. The 2‐year survival rate was 44% for thoracoscopy and 56% for thoracotomy (P = .942).Conclusion
Selected primary lung tumors in dogs can be safely resected with thoracoscopy and not affect long‐term outcome.4.
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Geoffrey R. Tick Colleen M. McColl Irfan Yolcubal Mark L. Brusseau 《Water, air, and soil pollution》2007,184(1-4):355-362
Robust measurements of porous-medium tortuosity are one of the many components needed for accurate characterization and prediction of fluid flow and contaminant transport in the subsurface. A gas-phase diffusive tracer-test method is evaluated for the in-situ measurement of tortuosity in the vadose zone. This technique presents an alternative to employing widely-used correlations to estimate tortuosity. A small-scale field study was conducted using a single well and a non-reactive gas-phase tracer (sulfur hexafluoride; SF6). Gas samples were collected from the injection point periodically after tracer injection into the soil matrix. An effective radius of influence of 50 cm was determined for the tests. An analytical solution was calibrated to the measured temporal concentration distribution, producing a fitted value for tortuosity. The value obtained from the tracer tests was compared to values estimated with several widely-used correlations. The value obtained from the tracer tests was generally larger than the values estimated with the correlations, which spanned a relatively wide range. The tracer-test method provides a means by which to determine in-situ measurements of tortuosity, allowing for better characterization of contaminant transport in the vadose zone. 相似文献
6.
Peter J. Steer Colleen H. M. Tashiro William D. Mcillveen Ray E. Clement 《Water, air, and soil pollution》1995,82(3-4):659-674
In early February 1990, vandals set fire to a used tire storage facility near Hagersville, Ontario, Canada, During the fire, the Ontario Ministry of Environment and Energy (MOEE) monitored the site and surrounding impact zone for numerous organic contaminants. Samples of air, soil, vegetation, runoff water, and oily residue were collected and analyzed for polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF). Air samples produced complex incineration patterns with a large number of isomers detected. Total toxicity equivalents (TEQ) at 1 km downwind of the fire were an order of magnitude higher than those at 3 km downwind. Soil samples collected during the fire did not show elevated PCDD or PCDF concentrations, however, low concentrations were detected in vegetation collected at 100 m and 200 m from the site. PCDD and PCDF concentrations in the foliage decreased with time but were still detectable for at least 200 days after the fire started. As the tires burned, water used to extinguish the fire caused runoff of oil and oily water. Unique patterns of PCDDs and PCDFs were detected in these samples. 相似文献
7.
de Brito ES de Araújo MC Alves RE Carkeet C Clevidence BA Novotny JA 《Journal of agricultural and food chemistry》2007,55(23):9389-9394
Many tropical fruits are rich in anthocyanins, though limited information is available about the characterization and quantification of these anthocyanins. The identification and quantification of anthocyanin pigments in four tropical fruits were determined by HPLC-MS/MS. Fruits studied included acerola (Malphigia emarginata), jussara (Euterpe edulis), jambol?o (Syzygium cumini), and guajiru (Chrysobalanus icaco). All four fruits were found to contain anthocyanin pigments. Anthocyanidin backbones included cyanidin, delphinidin, peonidin, pelargonidin, petunidin, and malvidin. Guajiru contained several acylated forms, while acerola, jussara, and jambol?o contained only nonacylated glycosides. These results demonstrate that these tropical fruits are rich in anthocyanins and that the anthocyanins are widely ranging in anthocyanidin backbone, glycosylation, and acylation. 相似文献
8.
免疫控制猪圆环病毒Ⅱ型相关疾病 总被引:1,自引:0,他引:1
笔者对猪圆环病毒Ⅱ型(PCV2)及其相关疾病的了解主要来自临床研究而非基础研究,所以多年来一直受PCV2与两种和其感染相关的主要综合征[即仔猪断奶后多系统衰弱综合征(PMWS)及猪皮炎和肾病综合征(PDNS)]之关系的报道所困扰. 相似文献
9.
Jacqueline M. Bishop Alison J. Leslie Sven L. Bourquin Colleen ORyan 《Biological conservation》2009,142(10):2335-2341
Unchecked exploitation of wildlife resources is one of the major factors influencing species persistence throughout the world today. A significant consequence of exploitation is the increasing rate at which genetic diversity is lost as populations decline. Recent studies suggest that life history traits affecting population growth, particularly in long-lived species, may act to moderate the impact of population decline on genetic variation and lead to remnant populations that appear genetically diverse despite having passed through substantial demographic bottlenecks. In this study we show that the retention of genetic variation in a partially recovered population of Nile crocodile is deceptive, as it masks the reality of a significant decline in the population’s effective size (Ne). Repeated episodes of unchecked hunting in the mid to late 20th century have today led to a five-fold decrease in the population’s Ne. Using current census data we estimate the contemporary Ne/N ratio as 0.05 and, in light of quotas that permit the ongoing removal of adults, simulated the likely effects of genetic drift on extant levels of variation. Results indicate that even if the current effective size is maintained, both allelic diversity and heterozygosity will decline. Our findings have complex implications for long-lived species; an emphasis on the retention of genetic variation alone, whilst disregarding the effects of population decline on effective size, may ultimately obscure the continued decline and extinction of exploited populations. 相似文献
10.
美国猪兽医师年会上提交了很多与猪Ⅱ型圆环病毒(PCV2)有关疾病的报告。人们对于仍在全球范围肆虐的猪Ⅱ型圆环病毒(PCV2)的了解正在日益增多。今年我们已从多个途径获得了有关此病的新信息,而最新的信息是在美国猪兽医 相似文献