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391.
Kwang Seop Kim Man Park Choong Lyeal Choi Dong Hoon Lee Young Jin Seo Chan Yong Kim Jong Su Kim Seok-In Yun Hee-Myong Ro Sridhar Komarneni 《Journal of Soils and Sediments》2011,11(3):416-422
Purpose
A large amount of nitrogen (N) fertilizers has been broadcasted over soil surface for reliable crop production. Unfortunately, the broadcasted N vulnerable to volatilization and leaching can lead to serious environmental problems. As a new approach to mitigate N loss of broadcasted fertilizers, massive intercalation of urea into montmorillonite (MMT) was recently proposed to innovatively enhance the urea use efficiency. This study focuses on demonstrating the behaviors of the urea intercalated into MMT in soils. 相似文献392.
A retrospective case-series study evaluated the prognosis of 853 dogs with acute kidney injury (AKI) based on the RIFLE (Risk, Injury, Failure, Loss and End-stage renal failure) criteria, derived from human medicine. The 30-day mortality of dogs with AKI in each class was found to be 23.8 per cent (40 of 168) dogs for Risk, 41.0 per cent (107 of 261) dogs for Injury and 78.5 per cent (333 of 424) dogs for Failure. Using the dogs in the Risk class as the reference, the mortality of dogs in either the Injury or Failure class was significantly higher than that of dogs in the Risk class (P<0.05). The longest median survival time was observed in the Risk class (nine days) and the shortest median survival time was observed in the Failure class (three days). Using a multiple logistic regression model, a new score that simultaneously considered RIFLE class, diarrhoea status and serum phosphorus level was calculated to predict prognosis. Evaluation using the area under the receiver-operating characteristic curve (AUROC) indicated that the new scoring method (AUROC 0.80) was a better prognostic indicator than using RIFLE criteria alone (AUROC 0.73). 相似文献
393.
OmpA is a virulence factor of Riemerella anatipestifer 总被引:1,自引:0,他引:1
Riemerella anatipestifer infection is probably the most economically important disease of farm ducks worldwide. The pathogen R. anatipestifer causes septicemia anserum exsudativa in ducks, but little is known about the molecular basis of its pathogenesis and the virulence factors involved. In this study, by deleting ompA gene from R. anatipestifer serotype 2 strain Th4, we constructed a mutant strain Th4ΔompA to investigate whether R. anatipestifer OmpA is an important virulence factor. Results showed that although the growth curve, bacterial and colony morphology of Th4ΔompA in tryptic soybean broth (TSB) or on TSB agar were similar to its parent strain Th4, the adhesion and invasion capacities of mutant strain to Vero cells were decreased significantly. Furthermore, the median lethal dose (LD(50)) of both strains was determined to measure the virulence with 10-day-old Cherry Valley ducklings. The results showed that LD(50) of Th4ΔompA mutant was >10(10) colony forming units (CFU), it was attenuated significantly in comparison with that of Th4 which LD(50) was 4.41 × 10(8) CFU. Additional analysis indicated that blood bacterial loading of ducklings infected with the Th4ΔompA mutant were much lower than those of Th4-infected ducklings. The results demonstrate that OmpA is a virulence factor of R. anatipestifer, and that it may act as an adhesin. 相似文献
394.
395.
Kang SI Heo EJ Cho D Kim JW Kim JY Jung SC Her M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(6):779-786
The multiple-locus VNTR analysis (MLVA) assay is a method frequently employed as a molecular epidemiological tool for Brucella genetic fingerprinting. The purpose of this study was to assess the genotyping of 77 B. canis isolates from 14 different dog breeding farms in Korea by the MLVA assay and to compare the epidemiological relationships between the Korean isolates and foreign ones. Simpson's diversity index for 17 loci showed a range from 0 to 0.846 in 77 B. canis isolates. B. canis isolates in Korea were observed to have high genetic diversity at the most variable loci and were divided into 30 distinct genotypes by phylogenetic analysis. Some B. canis isolates were closely related to previously typed isolates in other countries. The MLVA assay can be helpful to analyze the epidemiological correlation of B. canis isolates in domestic pet animals and to track the geographic origin by comparing the genetic patterns with foreign isolates. Therefore, the MLVA assay will be useful as a tool for control and preventive measures of canine brucellosis. 相似文献
396.
将狂犬病病毒(RV)糖蛋白(G蛋白)中和抗原表位串联表达的重组蛋白作为抗原,建立了检测RV中和抗体的间接ELISA技术。结果表明,最佳抗原包被量为2μg/孔,被检血清最佳稀释倍数为1:200。该方法与快速荧光灶抑制试验(RFFIT)的阳性符合率为88%,阴性符合率为96%。特异性试验表明,该抗原不与犬腺病毒I型、犬细小病毒、犬瘟热病毒、犬副流感病毒和犬冠状病毒阳性血清发生交叉反应,具有良好的特异性。板内和板间重复性试验的平均变异系数分别为2.7%和4.2%,具有良好的重复性,为动物RV中和抗体检测提供了简单快捷的检测方法。 相似文献
397.
丁铲 《中国预防兽医学报》2011,33(1)
新城疫病毒((Newcastle disease virus,NDV)是副黏病毒科副黏病毒亚科禽腮腺炎病毒属的成员之一,也是家禽的主要病原之一.NDV病毒粒子自然状态下呈多形性,大小150 nm~400 nm;病毒粒子内有长1 000 nm螺旋状的核衣壳结构,直径为17 nm~18 nm;囊膜上覆盖有直径8 nm~12nm 的糖蛋白纤突.NDV基因组为单股负链RNA,分子量5.2×106~5.7×106道尔顿.NDV基因组包括6个基因(31-NP-P-M-F-HN-L-51)编码至少8种蛋白(6种结构蛋白,和由P蛋白基因经RNA编辑,从移码了的阅读框翻译出2种非结构蛋白V和W蛋白). 相似文献
398.
Resection and anastomosis of the small colon was performed on 4 horses with vascular lesions (strangulating lipoma, mesenteric tear, dissecting haematoma) or functional obstruction (stricture) of this area of the bowel. The anastomoses were performed using a variety of suture materials in 2 layers. An appositional, full-thickness, simple, interrupted pattern was used in the first layer in all cases and oversewn with either a Cushing pattern (3 cases) or a Utrecht pattern (1 case). Post-operative complications associated with suture material and surgical technique were not seen. All horses were discharged from the hospital and all were alive more than one year after discharge. 相似文献
399.
Robert B. Duncan JR DVM PHD Jeryl C. Jones DVM PHD H. David Moll DVM MS Martha M. Moon DVM MS Dennis J. Blodgett DVM PHD Michael R. Vaughan PHD 《Veterinary radiology & ultrasound》2002,43(1):31-36
Congenital hyperplastic goiter and cretinism were documented in a 16 month-old male North American black bear (Ursus americanus). The cub was captured at approximately 8 months of age and maintained for an additional 8 months in captivity. Clinical signs included growth retardation, clumsiness, and facial dysmorphism. Hypothyroidism was documented by determining serum triiodothyronine (T3) and thyroxine (T4) levels. Lysosomal storage disease was ruled out by measuring various lysosomal enzyme activities. Serologic, radiographic, computed tomographic, necropsy, and histopathologic findings were consistent with congenital hypothyroidism and cretinism. 相似文献
400.
LUISITO S. PABLO DVM MS Diplomate ACVA ALISTAIR I. WEBB BVSC PhD FRCVS Diplomate ACVA WALTER T. McNICHOLAS JR DVM 《Veterinary surgery : VS》1995,24(6):531-534
The effects of intravenously administered atropine (0.2 mg/kg) and glycopyrrolate (0.01 mg/kg) on heart rate were studied in 10 conscious mature goats. In a drug cross-over fashion, either atropine, glycopyrrolate, or 0.9% saline solution was administered using the same volume (0.05 mL/kg). Atropine and glycopyrrolate caused a significant increase in heart rate ( P <.05), whereas saline solution (0.09%) did not. The mean percent changes in heart rate from baseline were similar for atropine and glycopyrrolate up to 14 minutes after administration. Thereafter, glycopyrrolate had a significantly greater mean change in heart rate than atropine, ie, up to 29 minutes ( P <.05). Within the atropine group, the mean percentage changes in heart rate became significantly lower compared with the initial increase (1 minute) starting at 11 minutes. For the glycopyrrolate group, the mean percent changes became significantly lower starting at 27 minutes. Glycopyrrolate and atropine had a mean percentage change in heart rate of greater than 1.0%, up to 31 and 22 minutes, respectively. At the doses used, glycopyrrolate had longer duration of action than atropine but the magnitude of increase was similar. 相似文献