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ABSTRACTCase history: Medical records were reviewed of horses (n?=?7) undergoing surgery for fracture of one or more facial bones extending into the paranasal sinuses that was repaired primarily within 24 hours of the time of injury using a rotational periosteal flap, between April 2009 and May 2017. A kick from another horse was the cause of the injury of three horses, and one horse was injured when it collided with a tree. The cause of the injury of three horses was unknown.Clinical findings and treatment: Fractures were of the right maxillary bone in two horses, the left maxillary bone in two horses, the left frontal and left nasal bones in two horses, and the right frontal bones in one horse. The fracture of all but one horse was accompanied by an open wound. The fracture of all seven horses was reduced, stabilised, and covered with a rotational, periosteal flap. Surgery was carried out while standing in six horses, and while anesthetised in one horse. All horses had a deficit in the fractured facial bones after the fracture was reduced. Four horses had complications following surgery, but all horses were reported to have excellent cosmetic outcomes and had retuned to their previous level of activity, as reported by their owners.Clinical relevance: Covering a primarily repaired sinofacial fracture of a horse with a rotational periosteal flap resulted in good cosmetic outcomes, and may be especially beneficial if the fracture is accompanied by loss of bone. 相似文献
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D. A. Castle 《Soil Use and Management》1986,2(2):58-61
Abstract. Much field drainage work in Great Britain includes costly permeable backfill material as a connector between mole drains, subsoiler fissures, or permeable subsoil layers and the pipe. This paper reviews the role of the Ministry of Agriculture in sponsoring research and advice on drainage design, as well as providing grant-aid to farmers for the installation of field drainage. As a result of this involvement permeable backfill is now regarded as an essential element in the drainage of clayey soils and springs. The cost is fully justified by the establishment and maintenance of highly efficient and flexible farming systems. These techniques are applicable to many countries where clayey, slowly permeable soils predominate. 相似文献
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Intact, unamended subsoil cores taken from two contrasting field sites were incubated in the laboratory at 12 °C under aerobic
(21% O2) and anaerobic (1.1–5.5% O2) conditions. Denitrification of 15N-NO3
– diffusing into the cores across a semi-permeable membrane was estimated by: (1) direct observation of 15N-labelled N2 and N2O, and (2) mass balance following sectioning at the end of the experiment. The in situ denitrification potential (rates where
the supply of NO3
– is not limited by diffusion) was estimated using a finite-difference approximation to a diffusion reaction equation based
on comparison of time and depth profiles of NO3
– and Br– in the incubated cores. Potentials between 0.2 and 2.5 mg N kg–1 day–1 were obtained under low O2 and natural C concentrations. These results indicate the potential for denitrification in glacial till subsoils to reduce
NO3
– leaching to ground or surface waters to levels unlikely to result in a pollution hazard. The major product of NO3
– reduction in these subsoils was observed to be N2, rather than the greenhouse gas and catalyst of stratospheric O3 removal, N2O.
Received: 31 October 1997 相似文献
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Abstract. The effects on nitrate leaching of incorporation of paper mill waste at three cultivation depths in fields previously cropped to iceberg lettuce and calabrese are reported. In the lettuce experiment, incorporation of 40 t DM paper mill waste/ha resulted in a decrease in N leaching (measured with suction cups) from 177 to 94 kg/ha (S.E.d = 23). Deep ploughing with and without paper waste increased N leaching from 105 kg/ha (normal ploughing or surface incorporation) to 172 kg/ha (S. E. d = 27). Measurements of nitrate leaching using deep soil cores showed a less clear cut effect. Nitrous oxide (N2 O) emissions were very high immediately after paper waste was ploughed in to a depth of 35 cm. Non–significant increases in biomass N content were measured in the spring following paper waste application. There was no significant reduction in plant N uptake in subsequent crops. Removal of above–ground crop residues did not have a significant effect on nitrate leaching or N2 O losses. In the calabrese experiment, application of 40 t DM paper mill waste/ha followed by summer cropping with iceberg lettuce caused a decrease in N leaching (measured using deep soil cores) from 227 to 152 kg/ha (S. E.d = 22, mean of all cultivation treatments). 相似文献