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141.
Five coronaviruses (CoVs) were detected in diarrheal feces from four zoo ruminant species: one wisent (Bison bonasus), two Himalayan tahr (Hemitragus jemlahicus), one sitatunga (Tragelaphus spekii), and one nyala (Tragelaphus angasii). We sequenced and analyzed the spike (S) and hemagglutinin/esterase (HE) genes of these viruses and compared the nucleotide (nt) and deduced amino acid (aa) sequences with those of other bovine CoV (BcoV) strains. Comparison of the entire deduced aa sequences of the S and HE glycoproteins revealed no specific differences that would account for discrimination between bovine-like CoV strains from zoo ruminants and BcoVs strains. In addition, the 99.9% aa identity among the five CoV strains revealed that the ruminants were infected by the same strain. Phylogenetically, bovine-like CoVs belong to group 2a CoVs, which are related most closely to the BcoV strains recently isolated in Korea. These data suggest that cattle are potential reservoirs for CoVs that are capable of infecting zoo ruminants. 相似文献
142.
Miyoung Yang Myoung-Sub Song Sung-Ho Kim Jong-Choon Kim Joong-Sun Kim Taekyun Shin Changjong Moon 《Journal of veterinary science (Suw?n-si, Korea)》2011,12(3):203-207
This in vitro study evaluated the detrimental effect of acute gamma (γ)-irradiation on rat immature hippocampal neurons. Rat immature hippocampal neurons (0.5 day in vitro) were irradiated with 0~4 Gy γ-rays. Cytotoxicity was analyzed using a lactate dehydrogenase release assay at 24 h after γ-irradiation. Radiation-induced cytotoxicity in immature hippocampal neurons increased in a dose-dependent manner. Pre-treatments of pro-apoptotic caspase inhibitors and anti-oxidative substances significantly blocked γ-irradiation-induced cytotoxicity in immature hippocampal neurons. The results suggest that the caspase-dependent cytotoxicity of γ-rays in immature hippocampal cultured neurons may be caused by oxidative stress. 相似文献
143.
Kim SH Yong HC Yoon JH Youn HY Yoshioka N Kano R Hasegawa A 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(10):1139-1140
A 6-month-old male golden retriever was presented with fever, bloody-watery diarrhea and mild cough. Parvovirus and Isospora canis infection was confirmed and successfully treated. Two weeks later, the dog had severe cough and mucopurulent nasal discharge. Aspergillus niger was cultured from endotracheal washings on blood agar at 37 degrees C. Treatment with itraconazole for about 10 weeks resolved the clinical signs. 相似文献
144.
Kim E. Hammond-Kosack Howard J. Atkinson Dianna J. Bowles 《Physiological and Molecular Plant Pathology》1989,35(6)
Systemic changes in gene expression have been analysed in potato plants following root infection with the cyst nematode Globodera rostochiensis. Root invasion by the pathogen induced major changes to occur in the composition of proteins extracted in intercellular fluid from the leaf apoplastic space. The changes involved the disappearance of innate leaf proteins and the accumulation of novel gene products. Analysis by SDS-PAGE indicated that the leaf polypeptides induced on nematode invasion are not cultivar or nematode pathotype-specific. Aspirin treatment of leaves induced a similar pattern to that induced systemically by nematodes, but several gene products were specific for the latter method of induction. In particular, two abundant [125I]-Con A binding polypeptides of high Mr accumulated in intercellular fluid only on aspirin treatment. The results are discussed in the context of the role of the extracellular leaf proteins and their modulation by systemic signals. 相似文献
145.
The primary objective of this study was to evaluate the effects of foliar boron and calcium application after harvest on the quantity and activity of pollen in the ‘Housui’ and ‘Wonwhang’ pears on a subsequent year. Pollen grains of the ‘Housui’ pear were cultured on germination medium, to which had been added boric acid (0, 25, 75, 100, 200, 300, 400, and 500 mg L−1) and calcium nitrate (0, 10, 25, 50, 100, 150, 200, 250, 300, 400, and 500 mg L−1). Boric acid, which was added to the germination media, exerted a significant stimulatory effect on both pollen germination and pollen tube growth, although pollen tube growth was inhibited at higher concentrations than 300 mg L−1. Calcium nitrate addition stimulated pollen germination, except at concentration of 500 mg L−1. However, pollen tube growth was significantly inhibited with increasing concentrations of calcium nitrate. In the orchard experiment, boron and calcium were sprayed at concentrations of 0, 100, 200, 500 or 1000 mg L−1 onto leaves after harvest, respectively. Boron and calcium content in the tissues as well as pollen production and growth were determined after these treatments. The foliar application of boron mainly resulted in an increase of boron concentration in buds. It also induced an increase in the weight of the anther and pollen in the following year. On the other hand, the foliar application of calcium resulted in an increase of calcium concentration mainly in the leaves, but pollen weight was decreased at high concentration treatment in the following year. The germination rate and tube growth of collected pollen were highest in the trees which had received boron treatment at a concentration of 200 mg L−1. In contrast, the germination rate and tube growth of collected pollen were decreased by calcium application at concentrations of 500 and 1000 mg L−1 without significant increase at lower concentrations. Consequently, the accumulation of boron in the developed buds of pear trees subjected to post-harvest foliar boron application generated positive effects on both the quantity and quality of pollen in the following year. 相似文献
146.
Kim CS Koh PO Cho JH Park OS Cho KW Kim GS Won CK 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(6):653-655
A male deformed Korean native calf was examined macroscopically. The deformed calf had no caudal vertebral columns from 5th lumbar vertebra, sacrum and coccygeal vertebrae. The spinal cord was terminated in the vertebral foramen of the 3rd lumbar vertebra. The cervical vertebrae had scoliosis and the 3rd and 4th cervical vertebrae were fused. The 2nd and 3rd lumbar vertebrae were fused and the left and right transverse processes of the 4th lumbar vertebra articulated with ala of the ilium. The rectum was greatly expanded by the imperforate anus and a rectourethral fistula was formed between the rectum and urethra. The deformed calf was recorded as a first documentation of sacrocaudal agenesis confirmed in a Korean native calf. 相似文献
147.
Serodiagnostic comparison of enzyme-linked immunosorbent assay and surface plasmon resonance for the detection of antibody to Porcine circovirus type 2 下载免费PDF全文
Ho-Seong Cho Tae-Jung Kim Jae-Il Lee Nam-Yong Park 《Canadian journal of veterinary research》2006,70(4):263-268
This paper describes the cloning and expression of the capsid protein of Porcine circovirus type 2 (PCV2) in an Escherichia coli expression system that was used to produce a fusion protein for subsequent immunologic studies: enzyme-linked immunosorbent assay (ELISA) and surface plasmon resonance (SPR). Polymerase chain reaction was used to amplify the gene encoding the capsid protein from the DNA of PCV2. The protein was then cloned into a pRSET prokaryotic expression vector. Western blot analysis revealed that the recombinant protein gave strong signals on a polyvinylidene difluoride membrane when exposed to the serum from a pig infected with PCV2. The expressed protein was purified and used as an antigen for the ELISA and SPR study. A protein chip based on SPR was developed, and the diagnostic potential of SPR was compared with that of ELISA with the use of 70 serum samples obtained from 6 pig farms. There was a strong positive correlation between the ELISA and SPR titers (r = 0.877, P < 0.01). Therefore, this recombinant capsid protein can be used as an antigen for serologic studies, and the SPR, a label-free method, appears to be a valuable and reproducible tool in the serodiagnosis of a PCV2 infection. 相似文献
148.
Effect of dietary selenium source, level, and pig hair color on various selenium indices 总被引:2,自引:0,他引:2
The first experiment evaluated the effects of feeding various levels of Se, two Se sources, and hair color on selenosis responses in growing-finishing pigs. The study conducted in two replicates was a 2 x 6 x 2 factorial arrangement in a split-plot design. Sodium selenite and Se-enriched yeast added at 0.3, 1, 3, 5, 7, and 10 ppm Se served as the main plot and pig hair color as the subplot. A total of 96 crossbred pigs were allotted and fed their treatment diets for a 12-wk period. White and dark (red or black) hair samples were collected from the dorsal-midline at the 4-, 8-, and 12-wk periods from one pig of each hair color from each treatment pen. Lower pig weights (P < 0.10) and daily gains (P < 0.05) occurred as dietary Se level increased when pigs were fed either Se source. Selenosis responses were somewhat more severe, when the inorganic Se source was fed. Alopecia and hoof separation were encountered after the 8-wk period when pigs were fed inorganic rather than organic Se. Plasma Se increased as dietary level increased (P < 0.01), when organic Se was provided (P < 0.01), and was higher (P < 0.05) when pigs were white-haired. A time x hair color x dietary Se level interaction (P < 0.05) occurred, in which hair Se concentration was higher in dark- than in white-colored pigs and increased as dietary Se level increased as the experiment progressed. The correlation coefficient between dietary Se level and hair Se concentration averaged 0.90 (P < 0.01). Cysteine was the amino acid in the highest concentration in hair, but this and other amino acids were not affected by Se level, Se source, or hair color. A second experiment was a 3 x 6 factorial arrangement in a split-plot design with three 9-mo-old gilts from each of the Yorkshire, Duroc, and Hampshire breeds to determine whether hair Se concentration differed by body location and breed. Hair samples were collected from the shoulder, back, rump, front-leg, belly, and hind-leg areas. Hair Se concentration was higher in red- and white-haired pigs and lower in black-haired gilts (P < 0.01). Higher hair Se concentrations (P < 0.05) occurred from the lower than from the upper body areas. Our results suggest that selenosis occurs at dietary levels > 5 ppm and that white-haired pigs exhibit alopecia sooner than dark-haired pigs. No difference in hair Se concentration occurred when diets were < 1 ppm Se, but as dietary Se level increased dark-haired pigs retained more Se in their hair than white-haired pigs. 相似文献
149.
Yinghua Li Seung-Beom Cha Youngil Park Bo-Ho Gong In-Yeong Jeong Hak-Soo Kim Min-Soo Kang Young-Suk Kim Chang Hoon Han Hyun-Kul Lee Si-Whan Song Chae-Gyoo Park Boo-Hyon Kang 《Journal of toxicologic pathology》2022,35(1):45
Platycodi radix is widely used in traditional herbal medicine for the treatment of bronchitis, asthma, pulmonary tuberculosis, hypertension, hyperlipidemia, and diabetes. This study aimed to investigate cell proliferation (Ki-67) and apoptosis (Caspase-3) potential in squamous cell hyperplasia of the stomach induced by a Platycodi radix water extract in a subchronic toxicity study. One hundred formalin-fixed, paraffin-embedded stomach tissues of rats treated with Platycodi radix at doses of 0, 500, 1,000, and 3,000 mg/kg body weight/day were used for the analysis. They were conventionally stained using hematoxylin and eosin (H&E) and immunohistochemically (IHC) stained using caspase-3 and Ki-67 antibodies. The incidence of squamous cell hyperplasia was significantly increased in the 3,000 mg/kg b.w./day treatment group in both sexes (p<0.01). However, the hyperplastic change was completely repaired after 4 weeks of recovery period. Ki-67 expression was similar in all groups, with no statistically significant differences among the groups. Caspase-3 expression was significantly increased in both sexes in the 3,000 mg/kg b.w./day treatment group (p<0.01), compared with the vehicle control groups, and then reduced to normal levels in the recovery groups in both sexes. In conclusion, this study showed that squamous cell hyperplasia induced by the Platycodi radix water extract in the limiting ridge of the stomach is not considered to be abnormal proliferative change; as a result, squamous cell hyperplasia is considered to be a non-adverse effect when induced by the oral administration of the Platycodi radix water extract once daily for 13 weeks in rats. 相似文献
150.