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891.
SHAO Qi QU Yang ZHU Zichen MENG Chunchun QIU Xusheng LIAO Ying TAN Lei SONG Cuiping LIU Weiwei SUN Yingjie DING Chan 《畜牧兽医学报》1956,51(9):2275-2283
When mammalian cells are stimulated by stress, multiple dense granular structures form in cells. These structures are called stress granules (SGs). G3BP1 is an important component and marker protein of stress granules. To dynamically monitor the formation of SG, the HeLa cell line stably expressing GFP-G3BP1 was constructed. The G3BP1 gene was amplified and cloned into a lentiviral vector to obtain a recombinant plasmid Lenti-GFP-G3BP1. The three-plasmid lentiviral packaging system was used to package the lentiviral particles expressing GFP-G3BP1, which were used to infect HeLa cells. The positive cells were initially selected by puromycin, and further selected by limited dilution to get the monoclonal cells stably expressing GFP-G3BP1. The function and expression of GFP-G3BP1 in the cell line were detected by Western blot and immunofluorescence assays. The obvious cytoplasm-specific fluorescence of G3BP1 was observed. Western blot results show a GFP-G3BP1 specific band, indicating that the HeLa cell line stably expressing GFP-G3BP1 was constructed successfully. Finally, the formation of SG in response to ARS/heatshock/Newcastle disease virus treatment were dynamically monitored. The results showed the gradual accumulation of SGs in response to these treatments. The specific cell line and method we established have laid the foundation for subsequent research on SG and Newcastle disease virus. 相似文献
892.
Multielement concentrations in liver and kidney tissues from five species of Canadian slaughter animals 总被引:1,自引:0,他引:1
C D Salisbury W Chan P W Saschenbrecker 《Journal of the Association of Official Analytical Chemists》1991,74(4):587-591
The present paper describes results of a national survey conducted between 1982 and 1989 to determine residues of arsenic, cadmium, copper, mercury, lead, selenium, and zinc in Canadian slaughter animals. Liver and kidney tissues from cattle, swine, poultry, horses, calves, and sheep were tested. Arsenic was found in most avian and porcine samples, and their respective means of 0.36 and 0.26 micrograms/g in liver were 7 to 12 times higher than mean concentrations found in the other species. Cadmium was found in the tissues of all species; however, levels were consistently highest in equine samples with mean values of 3.09 and 27.7 micrograms/g in liver and kidney, respectively. Copper levels greater than 150 micrograms/g were found predominantly in liver from calves and sheep, with values considerably lower in the remaining species. Mercury levels were low or not detected in all species except horses. Ninety % of equine kidneys and 54% of equine livers had mercury concentrations greater than 0.01 microgram/g, with mean values of 0.18 and 0.06 microgram/g, respectively. Lead was found in tissues of all species; however, values greater than 2 micrograms/g were found only in 2 kidneys from adult cattle and 1 kidney from a horse. Selenium, tested only in cattle, was found at mean concentrations of 0.28 microgram/g in liver, and 0.92 microgram/g in kidney. Relatively high zinc levels were found in livers of horses, pigs, and calves, with respective mean concentrations of 67.3, 65.6, and 70.2 micrograms/g. 相似文献
893.
Piroxicam Therapy in 34 Dogs With Transitional Cell Carcinoma of the Urinary Bladder 总被引:11,自引:1,他引:10
Deborah W. Knapp Ralph C. Richardson Thomas C.K. Chan Gerald D. Bottoms William R. Widmer Dennis B. DeNicola Robert Teclaw P.L. Bonney Thomas Kuczek 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1994,8(4):273-278
Thirty-four dogs with histopathologically confirmed, measurable, nonresectable transitional cell carcinoma of the urinary bladder were treated with piroxicam (0.3 mg/kg PO sid) and were evaluated for tumor response and drug toxicity. Dogs were evaluated at the Purdue University Veterinary Teaching Hospital by means of physical examination, thoracic and abdominal radiography, cystography, complete blood count, serum biochemistry profile, and urinalysis. In selected cases, prostaglandin E2 (PGE2 ) concentrations in plasma and in supernatants of stimulated monocytes, and natural killer cell activity were quantified, Dogs were evaluated before therapy and at 28 and 56 days after initiation of therapy. Dogs with stable disease or remission at 56 days remained on the study and were evaluated at 1 to 2 month intervals. Tumor responses were 2 complete remissions, 4 partial remissions, 18 stable diseases. and 10 progressive diseases. The median survival of all dogs was 181 days (range, 28 to 720+ days), with 2 dogs still alive. Piroxicam toxicity consisted of gastrointestinal irritation in 6 dogs and renal papillary necrosis (detected at necropsy) in 2 dogs. Monocyte production of PGE2 appeared to decrease with therapy in dogs whose tumors were decreasing in size, and increased in dogs with tumor progression. A consistent pattern in natural killer cell activity was not observed. In vitro cytotoxicity assays against 4 canine tumor cell lines revealed no direct antitumor effects of piroxicam. In summary, antitumor activity, which was not likely the result of a direct cytotoxic effect, was observed in dogs with transitional cell carcinoma of the bladder treated with piroxicam. 相似文献
894.
Chan JP Chu CC Fung HP Chuang ST Lin YC Chu RM Lee SL 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(1):43-46
To obtain a basal concentration of serum Haptoglobin (Hp) in cattle in Taiwan, Hp concentrations were measured from serum samples collected from 10 healthy heifers, every week for one year. The values were also compared with those collected from 15 cows diagnosed with postpartum metritis. The heifers were successfully impregnated by artificial insemination six months after the tests. Hp concentrations were also measured in the serum collected from 11 other cows within 3 weeks after parturition. The Hp assay developed in this study gave a good correlation (r=0.893)with Western blotting. The Hp concentration of 454 serum samples from the 10 heifers had a mean value of 83.6 +/- 34.1 mg/l, and there was no significant difference among individual heifers. The basal value of Hp in heifers was calculated as less than 73.6 mg/l. No significant difference in Hp concentration was observed among the 10 heifers during cold and warm seasons (19.8 +/- 2.2 degrees C vs 27.3 +/- 1.4 degrees C), or before and after pregnancy. The mean serum Hp concentration from cows suffering from postpartum reproductive disorders was 1133.5 +/- 627.1 mg/l, which was significantly greater than the serum of healthy heifers and postpartum cows (104.6 +/- 61.0 mg/l) (P<0.05). These results demonstrate that Hp concentration may be a useful indicator for cows with postpartum reproductive disorders. 相似文献
895.
896.
鸡新城疫酶联免疫诊断试剂盒的研制 总被引:1,自引:0,他引:1
将ELISA检测鸡新城疫病毒特异性IgM抗体的方法试剂盒化,确定其外包装材料、规格、盒内组成,并对酶标板的包被、质量控制、保存期,酶标抗鸡IgM(μ链)单克隆抗体的冻干、保存,组盒后的ELISA诊断试剂盒的特异性、敏感性、符合率、可重复性、保存期等作了详细的研究。先后制备试剂盒18个批次,用于全国9个省的29个大型鸡场或兽医诊断站,检测血样3628份,其中阳性2959份。 相似文献
897.
Hao B Gong W Ferguson TK James CM Krzycki JA Chan MK 《Science (New York, N.Y.)》2002,296(5572):1462-1466
Genes encoding methanogenic methylamine methyltransferases all contain an in-frame amber (UAG) codon that is read through during translation. We have identified the UAG-encoded residue in a 1.55 angstrom resolution structure of the Methanosarcina barkeri monomethylamine methyltransferase (MtmB). This structure reveals a homohexamer comprised of individual subunits with a TIM barrel fold. The electron density for the UAG-encoded residue is distinct from any of the 21 natural amino acids. Instead it appears consistent with a lysine in amide-linkage to (4R,5R)-4-substituted-pyrroline-5-carboxylate. We suggest that this amino acid be named l-pyrrolysine. 相似文献
898.
将16只SPF鸡分成4组,每组4只,分别接种新城疫油乳剂苗,新城疫、传染性支气管炎、传染性法氏囊病三联油乳剂苗,LaSota弱毒苗和Mukteswer苗。接种后每隔2d采血1次,用ELISA测定新城疫特异性IgM和IgG抗体。结果:油乳剂灭活苗接种组均无特异性IgM抗体出现,特异性IgG抗体高峰期出现在接种后22d,LaSota弱毒苗和Mukteswer苗接种组均有特异性IgM抗体出现,高峰期为接种后第9d。各接种组经强毒攻击后,均出现IgM反应,IbG呈典型的回忆反应。进一步试验用LaSota灭活苗经肌肉、静脉接种和加氢氧化铝胶佐剂后肌肉接种,经测定,接种鸡均无或仅有很低水平的特异性IgM抗体产生。 相似文献
899.
Brain edema: induction in cortical slices by polyunsaturated fatty acids 总被引:18,自引:0,他引:18
The presence of polyunsaturated and saturated fatty acids in leukocytic membranes prompted study of their possible role in the induction of brain edema. Polyunsaturated fatty acids including sodium arachidonate, sodium linoleate, sodium linolenate, and docasahexaenoic acids induced edma in slices of rat brain cortex. This cellular edema was specific, since neither saturated fatty acids nor a fatty acid containing a single double bond had such effect. 相似文献
900.