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501.
Matthew C Reed Annette M O'Connor Kyoung-Jin Yoon Vickie L Cooper 《Journal of veterinary diagnostic investigation》2008,20(1):124-126
Handling practices of specimens may affect the sensitivity or specificity of diagnostic tests. In this study, as part of the Voluntary Iowa Bovine Viral Diarrhea Virus Screening Project held in 2006, 2 sample-handling practices were evaluated to determine how they affect the sensitivity and specificity of the antigen-capture enzyme-linked immunosorbent assay (ACE) for bovine viral diarrhea virus (BVDV). The null hypotheses investigated were 1) that maintenance of samples at room temperature would not be associated with decreased sensitivity, and 2) that continued use of a single pair of ear notchers would not be associated with cross-contamination of virus from 1 notch to another and reduce specificity. These hypotheses were tested in 2 studies by collecting known positive and negative samples and giving groups of samples different treatments. The first study used ACE on 4 groups of skin samples, all from a known-positive animal. Each group was subjected to different lengths of time at room temperature, from 24 to 96 hours at 24-hour intervals. No difference in test results was found between specimens subjected to different lengths of time at room temperature. The second study tested the effects of giving 3 different treatments to an ear notcher in between sample collecting (water rinse, Nolvasan solution rinse, or no treatment) on ACE results. No effect on sensitivity or specificity of ACE was observed. No difference in test results was found between the 3 ear-notcher treatment groups. The sample handling practices evaluated appeared to have little impact on test sensitivity or specificity of ACE for BVDV. 相似文献
502.
Ji-Hey Lim Dae-Yong Kim Jung-hee Yoon Wan Hee Kim Oh-kyeong Kweon 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(2):215-217
An eight-week-old female Cocker Spaniel was presented with ataxia, dysmetria and intention tremor. At 16 weeks, the clinical signs did not progress. Investigation including imaging studies of the skull and cerebrospinal fluid analysis were performed. The computed tomography revealed a cyst-like dilation at the level of the fourth ventricle associated with vermal defect in the cerebellum. After euthanasia, a cerebellar hypoplasia with vermal defect was identified on necropsy. A polymerase chain reaction amplification of cerebellar tissue revealed the absence of an in utero parvoviral infection. Therefore, the cerebellar hypoplasia in this puppy was consistent with diagnosis of primary cerebellar malformation comparable to Dandy-Walker syndrome in humans. 相似文献
503.
Hun-Young Yoon F.A. Mann Soon-wuk Jeong 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(3):335-337
Two sexually intact male Bengal cats, one a 4-month-old weighing 2.8 kg and the other, a 3-month-old weighing 2.0 kg, were presented to the University of Missouri-Columbia Veterinary Teaching Hospital for evaluation of respiratory distress. On initial presentation, both cats were dyspneic, exercise intolerant, and had marked concave deformation of the caudal sternum. Surgical correction of pectus excavatum was performed using a cylindrical external splint and U-shaped external splint. Post-operative thoracic radiography revealed that there was decreased concavity of the sternum and increased thoracic height at the level of the caudal sternebrae in both cats. 相似文献
504.
Youn-Jeong Lee Haan-Woo Sung Jun-Gu Choi Eun-Kyoung Lee Hachung Yoon Jae-Hong Kim Chang-Seon Song 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(3):301-308
Recombinant baculoviruses containing the fusion (F) and hemagglutinin-neuraminidase (HN) glycoprotein gene of the viscerotropic velogenic (vv) Newcastle disease virus (NDV) isolate, Kr-005/00, and a lentogenic La Sota strain of the NDV were constructed in an attempt to develop an effective subunit vaccine to the recent epizootic vvNDV. The level of protection was determined by evaluating the clinical signs, mortality, and virus shedding from the oropharynx and cloaca of chickens after a challenge with vvNDV Kr-005/00. The recombinant ND F (rND F) and recombinant HN (rND HN) glycoproteins derived from the velogenic strain provided good protection against the clinical signs and mortality, showing a 0.00 PI value and 100% protection after a booster immunization. On the other hand, the combined rND F + HN glycoprotein derived from the velogenic strain induced complete protection (0.00 PI value and 100% protection) and significantly reduced the amount of virus shedding even after a single immunization. The rND F and rND HN glycoproteins derived from the velogenic strain had a slightly, but not significantly, greater protective effect than the lentogenic strain. These results suggest that the combined rND F + HN glycoprotein derived from vvNDV can be an ideal subunit marker vaccine candidate in chickens in a future ND eradication program. 相似文献
505.
Choi Yu Ri Kim Young-Nam Yoon Jung-Hwan Dickinson Nicholas Kim Kye-Hoon 《Journal of Soils and Sediments》2021,21(5):1962-1973
Journal of Soils and Sediments - Microplastics have been widely reported to contaminate aquatic environments, particularly impacting marine organisms, but little is known of microplastic... 相似文献
506.
Chang Yoon Jeong Alan DeRamus Jim J. Wang Lora L. Goodeaux 《Archives of Agronomy and Soil Science》2013,59(1):103-118
The effect of three sugarcane (Saccharum officinarum L.) residue-management plans on nitrogen losses in surface runoff and sub-surface leachate was studied for 3 years. The three management plans evaluated were conventional burning (CB), compost application with burning (COMB), and remaining green cane trash blanketing (GCTB) treatment. In the CB treatment, sugarcane residue was burned after harvest. The COMB treatment consisted of compost applied at ‘off bar’ with sugarcane residue burned immediately after harvest. Compost was applied in the amount of 13.4 Mg ha?1 annually. Surface runoff was collected with automatic refrigerated samplers and sub-surface leachate was collected with pan lysimeters over a period of 3 years. Total nitrogen (TN), NO3/NO2–N, and NH4–N were measured. The mean losses of nitrogen (TN, NO3/NO2–N, and NH4–N) from the COMB treatment after the burning procedure (post-harvest, years 2 and 3) were on average 2.7 times higher than those before harvest and burning (pre-harvest, year 1). Mean leaching losses of NO3/NO2–N were 0.36, 0.82, and 0.10 kg ha?1 for the CB, COMB, and GCTB treatment, respectively. The losses of NO3/NO2–N from the GCTB treatment in surface runoff and sub-surface leachate were significantly reduced compared to the CB and COMB treatment. 相似文献
507.
Cho Jae-Young Han Kang-Wan Choi Jin-Kyu Kim Young-Joo Yoon Kwang-Sik 《Soil Science and Plant Nutrition》2013,59(3):301-306
Abstract The study was carried out to investigate the water balance and runoff and infiltration losses of nutrients in a paddy field plot located in southern Korea. Field monitoring was carried out during the cropping season from May 1, 1999 to September 30, 2000. The soil of the experimental paddy field belonged to the Jisan series (SiL; fine loam, mixed, mesic Fluventic Haplaquepts) covering on area of 5,000 m2 (100 m × 50 m). The measured input quantities of N and P into the paddy field were as follows: 122 and 140 kg N ha?1 and 29 and 30 kg P2O5 kg ha?1 from chemical fertilizer, 20 and 28 kg N ha?1 and 0.35 and 0.36 kg P ha?1 from precipitation, and 26 and 35 kg N ha?1 and 0.57 and 0.72 kg P ha?1 from irrigation water, respectively. The measured outputs of N and P during the study period were as follows: 48 and 52 kg N ha?1 and 1.1 and 1.6 kg P ha?1 from runoff water, and 9 and 12 kg N ha?1 and 0.04 and 0.05 kg P ha?1 from infiltration. The runoff loading was the highest in June, presumably because of the higher concentrations of chemical components associated with chemical fertilizer application. The runoff losses of nutrients were compared to the amounts of nutrients supplied by chemical fertilizers. It was found that the losses of N accounted for 34.3 and 42.6% of the chemical fertilizer applied, while those of P accounted for 3.8 and 5.3%. The ratio between nutrient losses by infiltration and the chemical fertilizer applied was 6.4 and 9.8% for N and 0.1 and 0.2% for P, respectively. 相似文献
508.
Yowhan Son Yoon Young Lee Chon Young Lee Myong Jong Yi 《Journal of plant nutrition》2013,36(11):1841-1853
ABSTRACT Rates of nitrogen (N) fixation, soil N availability, and aboveground biomass were measured in 27-year-old pure and mixed Alnus hirsuta and Pinus koraiensis plantations in central Korea. Nodule biomass and N fixation were 179.3 kg ha? 1 and 46.6 kg ha? 1yr? 1 for the pure A. hirsuta plantation (PA) and 95.2 kg ha? 1 and 41.1 kg ha? 1yr? 1 for the mixed A. hirsuta + P. koraiensis plantation (MAP), respectively. A. hirsuta seemed to provide more than two thirds of annual N requirement for P. koraiensis.Rates of acetylene reduction were significantly related to soil temperature (R2 = 0.51, P < 0.001), but not to soil moisture content. Total inorganic N [ammonium (NH4 +)plus nitrate (NO3 ?)] availability measured using ion exchange bags were significantly higher under PA (27.91 μ g-N bag? 1) and MAP (31.34 μ g-N bag? 1) than under the pure P. koraiensis plantation (PP) (14.31 μ g-N bag? 1). Especially soils under the influence of A. hirsuta showed at least 2 fold increase in resin total inorganic N concentrations. Total aboveground biomass (Mg ha? 1) was 147.3 for PA, 145.8 for MAP, and 174.8 for PP, respectively, and was not significantly different among plantations. A. hirsuta significantly increased soil N availability; however, the influence of N fixation on aboveground biomass was not significant for the study plantations. 相似文献
509.
Gyu-Tae Park Jung-Won Yoon Sang-Bin Yoo Young-Chul Song Parkyong Song Hyoung-Kyu Kim Jin Han Sung-Jin Bae Ki-Tae Ha Natalia P. Mishchenko Sergey A. Fedoreyev Valentin A. Stonik Moon-Bum Kim Jae-Ho Kim 《Marine drugs》2021,19(5)
Scleroderma is an autoimmune disease caused by the abnormal regulation of extracellular matrix synthesis and is activated by non-regulated inflammatory cells and cytokines. Echinochrome A (EchA), a natural pigment isolated from sea urchins, has been demonstrated to have antioxidant activities and beneficial effects in various disease models. The present study demonstrates for the first time that EchA treatment alleviates bleomycin-induced scleroderma by normalizing dermal thickness and suppressing collagen deposition in vivo. EchA treatment reduces the number of activated myofibroblasts expressing α-SMA, vimentin, and phosphorylated Smad3 in bleomycin-induced scleroderma. In addition, it decreased the number of macrophages, including M1 and M2 types in the affected skin, suggesting the induction of an anti-inflammatory effect. Furthermore, EchA treatment markedly attenuated serum levels of inflammatory cytokines, such as tumor necrosis factor-α and interferon-γ, in a murine scleroderma model. Taken together, these results suggest that EchA is highly useful for the treatment of scleroderma, exerting anti-fibrosis and anti-inflammatory effects. 相似文献
510.
Se-Yeoun Cha Min Kang Ran-Hee Yoon Choi-Kyu Park Oun-Kyoung Moon Hyung-Kwan Jang 《Comparative immunology, microbiology and infectious diseases》2013
An investigation was carried out to determine the prevalence and antibiotic resistance of Salmonella serotypes at South Korean duck farms. A total of 7119 samples collected from 72 duck farms in five provinces were examined from 2011 to 2012. The overall prevalence of Salmonella serotypes was 43.4% (69/159) in duck flocks from 65.2% (47/72) of the duck farms. Eighty-five strains were isolated from 69 duck flocks. Three serotypes of Salmonella enterica were identified such as S. Typhimurium (39/85), S. Enteritidis (44/85), and S. London (2/85). The prevalence of Salmonella infection decreased significantly in 3-week-old ducks compared to that in 1-week-old ducks (P < 0.05). All isolates except one were resistant to at least one antimicrobial and 27% of the isolates were resistant to 5–16 antimicrobials. Our findings provide baseline information on the degree of Salmonella infection and distribution of Salmonella serotypes in ducks and indicate that ducks should be considered an important source of foodborne pathogens. 相似文献