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Purpose To evaluate the corneal changes immediately after diamond burr debridement of superficial corneal wounds in dogs. Spontaneous chronic corneal epithelial defects (SCCEDs) are the most common form of canine recurrent corneal ulcers. The diamond burr has been used in the management of corneal lesions in humans since 1983. Recently, it has been successfully used in the treatment of SCCEDs in dogs; however, little has been documented as to its mechanism of action. Methods Five adult female research dogs euthanized for reasons unrelated to the study were included, providing 10 normal eyes. An excimer laser spatula was used for epithelial removal after delineation with an 8 mm punch biopsy trephine. Diamond burr debridement was performed for 30 and 45 s in five eyes each (groups 1 and 2 respectively). The procedure was performed on the ventral half of the experimental defect as well as ventral normal cornea, immediately after euthanasia, and prior to enucleation. Samples were processed routinely for histologic evaluation and stained with periodic acid–Schiff. Results No stromal defects could be identified under light microscopy. In experimental corneal wounds, multi‐focal areas remained covered by the epithelial basement membrane (BM) after diamond burr treatment in both groups (group 1 = 48%±16SD, group 2 = 26%±12SD). Removal of BM on group 2 was significantly higher than group 1 (P < 0.05). Conclusions The diamond burr allows a safe method of debridement and does not create defects beyond the epithelial BM in corneal wounds in normal dogs. Evaluation of the diamond burr debridement in cases of SCCEDs is warranted. 相似文献
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Two dedicated light flash observing sessions were conducted by one of the crewmen during the Skylab 4 mission. Analyses of his observations reveal a strong correlation between flash frequency and primary cosmic-ray flux, and an even stronger correlation between flash frequency and the South Atlantic Anomaly (SAA) region of the inner belt trapped radiation. Calculations indicate that an all-proton inner belt probably cannot produce the observed SAA flash rate, and they suggest that there may exist a previously unobserved inner belt flux of multiply charged nuclei. 相似文献
245.
ABSTRACT Cool and wet soils at the time of soybean [Glycine max (L.) Merrill] planting in the northern Great Plains may reduce early crop growth and retard nitrogen (N) fixation. Application of N as starter fertilizer may increase initial growth of soybean, but may also negatively impact N fixation when environmental conditions improve. The objective of this study was to evaluate the impact of low rates of N applied at planting on soybean N fixation and crop growth in the northern Great Plains. A field experiment (2000–2002) was established within a two-year corn [Zea mays (L.)] soybean rotation using a split-plot design with four replications. Whole plots were no-tillage (NT) and conventional tillage (CT) and the split plots were starter fertilizer (two sources × four rates) treatments. Nitrogen sources were either ammonium nitrate (AN) or urea (UR) each applied at 0, 8, 16, and 24 kg N ha?1. Biomass in both 2000 and 2001 growing seasons increased significantly with increasing N rate at both growth stages (R1 and R7) and at the R1 stage in 2002. Ureide concentration and relative ureide decreased with increasing N rate at the R1 stage in all years, indicating a decrease in N fixation up to that point in crop development. This decrease in N fixation was not present at the R7 stage, but the significant increase in plant growth including yield was still present, indicating possibly that starter fertilizer can positively impact soybean production in the cool environmental conditions of the northern Great Plains. However, the positive impact on plant growth and yield is dependent on in-season environmental conditions and time of planting. 相似文献
246.
Giami SY Akusu MO Emelike JN 《Plant foods for human nutrition (Dordrecht, Netherlands)》2001,56(1):61-73
The chemical composition and functional properties of ungerminated and germinated seeds of four advanced lines of cowpeas (IT81D-699, IT82E-18, IT84S-2246-4 and TVx 3236) were investigated. Ungerminated seeds contained 20.1 to 25.8% crude protein, 2.0 to 2.2% lipid, 115.1 to 210.0 mg phyticacid/100 g and 8.9 to 9.6 mg iron/100 g. The polyphenol contents of the brown- and cream-colored beans were similar (192.0 to 196.0 mg/100 g) but were significantly (p<0.05) higher than the amount (99.8 mg/100 g) found in the white beans. Germination increased the crude protein content, total phosphorus content, nitrogen solubility, fat absorption capacity and foam capacity but decreased ether extract, polyphenol and phytic acid contents, water absorption capacity, bulk density and foam stability of all cowpea lines. Incorporation of up to 0.2 M NaCI improved foam volume. Ungerminated seeds had high water (2.3–3.2 g/g) absorption capacities, while germinated seeds had high fat (3.1–3.6 g/g) absorption capacities. TVx 3236 and IT81D-699 might be selected for combining such characteristics as high crude protein, low phytic acid content and good foaming properties into a single cowpea line through breeding. 相似文献
247.
Extract When the suspected existence of this disease in New Zealand was first notified in 1955, the author prepared a review of all available literature (in the English language) at Wallaceville Animal Research Station, in order to help confirm the diagnosis of the disease. A summary of that review is presented here. 相似文献
248.
R.G. Clark Juliet Burbage P.McD. Marshall T. Valler D. Wallace 《New Zealand veterinary journal》2013,61(11):199-201
Abstract Extract Madam:- Cobalt deficiency has long been recognised in New Zealand as a disease in sheep and cattle which may occur when they graze pastures of low cobalt content <0.08 mg/kg DM and >0.04 mg/kg DM respectively. (2) In recent years the farming of red deer (Cervus elaphus) on soil types known to be marginally, moderately or severely deficient(1) has raised the question of how susceptible these species are to cobalt deficiency. To the authors' knowledge there is no published information on the susceptibility of red deer to cobalt deficiency. 相似文献
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250.
Clinical signs of hyperventilation, muscle weakness and lethargy were recognised in a one-year-old female Bichon Frise and a three-year-old male Poodle. One dog was also hyperexcitable and pyrexic. The diagnosis of renal tubular acidosis was confirmed by demonstrating the tendency to an elevated urine pH, a low blood pH and low blood bicarbonate level, and by eliminating other causes of metabolic acidosis. Both dogs were treated with oral sodium bicarbonate resulting in improvement in their clinical condition and a return to near normal blood pH and bicarbonate levels. 相似文献