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991.
Carvalho T Elias AP Nunes T Peleteiro MC Dias S 《Veterinary immunology and immunopathology》2008,121(3-4):344-358
Angiogenesis and inflammation are two processes regulated by numerous common molecular mechanisms. Inflammation can stimulate angiogenesis, and angiogenesis can facilitate inflammation; both mechanisms have been shown to be involved in carcinogenesis. With this study we sought to gain an understanding of the molecular mechanisms involved in tumor angiogenesis and inflammation in urinary bladder tumors. Tumor specimens were collected at slaughter from Friesian cows chronically exposed to bracken fern. Bracken chronic toxicity is characterized by the presence of multiple mixed tumors in the bladder, being reported throughout the world under the designation of bovine enzootic hematuria. We conducted molecular analyses of angiogenic factors and chemokine production by real-time RT-PCR, and also assessed microvessel density (MVD), microvessel pericyte coverage index (MPI) to reveal mature vessels, the extent of tumor-infiltrating leukocytes (TILk) and tumor cell apoptosis and proliferation in both epithelial and endothelial-derived bovine urinary bladder tumors. We defined a profile of chemokines/chemokine receptors (Mip1beta, CCR1) and angiogenesis-related factors (VEGF, VEGFR2) that allow distinguishing between urothelial carcinomas (epithelial origin) and hemangiosarcomas (endothelial origin). Taken together, our data reveals previously unrecognized paracrine and autocrine chemo-angiogenic loops in the context of bovine urinary bladder tumorigenesis. 相似文献
992.
993.
Graham SP Saya R Awino E Ngugi D Nyanjui JK Hecker R Taracha EL Nene V 《Veterinary immunology and immunopathology》2007,115(3-4):383-389
Enhancement of the induction of cytotoxic T-cell responses by immunostimulatory CpG oligodeoxynucleotides has been described in humans and mouse models. The present study attempted to address whether CpG has a similar effect in cattle. Immunisation of cattle with a recombinant form of the polymorphic immunodominant molecule from Theileria parva emulsified with immunostimulatory CpG oligodeoxynucleotides in adjuvant had no effect on the induction of antibody responses including the isotype profile, but significantly enhanced the induction of cytolytic responses that were mediated by CD4+CD3+ T cells utilizing the perforin-granzyme pathway. 相似文献
994.
Elias Milios Elias Pipinis Kyriaki Kitikidou Maria Batziou Stelios Chatzakis Sofia Akritidou 《New Forests》2014,45(2):165-177
The present study was conducted in a lowland degraded Quercus remnant forest in northeastern Greece. In 2006, ten plots of 50 m × 50 m were randomly selected in two site types. Site type A is covered by Quercus pubescens–Quercus frainetto stands that are under grazing pressure. In Site type B there are Q. pubescens stands and grazing pressure is more intense. Inside these plots 180 subplots of 2 m × 2 m were established in three regeneration environments and the number of sprouts and seedlings was counted. The three regeneration environments were: (a) rather dense groups of trees, (b) areas with bare soil that alternate with areas with grazed herbs and (c) areas covered only from sparse scattered trees. Moreover the regeneration plants were classed as recently grazed and not recently grazed plants. Six years later, 180 regeneration plants having a height equal to or over 20 cm were selected and were classed as seedlings or sprouts. Sprouts were the dominant form in regeneration. The sprouting ability of Q. pubescens and Q. frainetto seems to be an adaption that enables them to endure grazing. Grazing was the main factor that determined the distribution of regeneration. The ecological differences of the two species do not seem to substantially influence their distribution in the different regeneration environments. It seems that intense grazing keeps the regeneration plants in low height. However, regeneration density can be considered adequate for the perpetuation of the studied stands if the grazing stops. 相似文献
995.
996.
997.
Eggs of the European lobster, Homarus gammarus (L.), were exposed to malachite green (5, 10, 15 mg 1–1: 10 min), glutaraldehyde (50, 100, 150 mg 1–1: 3 min) and iodine as BuffodineTM (50, 100, 150 mg 1–1: 10 min). The efficiency of the treatments was tested by incubating eggs individually in wells of multiwell dishes with TSB agar for 14 days after exposure. In order to find any effect on viability, batches of 30 eggs from each of three females were incubated artificially in a recirculation system for 19 days and repeatedly exposed to the disinfectants. Iodine as Buffodine (150 mg 1–1) was the only treatment that resulted in a significant decrease of the bacterial growth on lobster eggs, but the treatment also resulted in inhibited hatching compared with the control group. Thus, our results indicate that treatment with 150mg–1 iodine as Buffodine could be a strategy for reducing bacterial growth on lobster eggs when massive egg mortality due to bacteria is otherwise unavoidable. The treatment could, however, lead to decreased viability of larvae due to inhibited hatching. 相似文献
998.
为了扭转贵州省北部地区早熟温州蜜柑(Citrus unshiu Marc.)生产大小年现象普遍的现状,并为制订橘园科学的栽培技术方案与合理的管理措施提供参考,试验历经7年2005~2011对早熟温州蜜柑控制大小年的栽培技术进行了实地配套优化研究。结果表明,通过合理的树体整形、加强土肥水管理、有针对性地花果管理、有效控制和综合防治病虫害等配套栽培技术应用,能够显著提高当地早熟温州蜜柑果园果实的产量,使大小年的产量差距控制在,10%~15%以内,把原来大小年现象严重的橘园变成了产量较为稳定的丰产园,同时还提高了早熟温州蜜柑果实的商品率,取得了良好的经济效益. 相似文献
999.
Highly sensitive ion pair liquid chromatographic determination of albendazole marker residue in animal tissues 总被引:2,自引:0,他引:2
Fletouris DJ Papapanagiotou EP Nakos DS Psomas IE 《Journal of agricultural and food chemistry》2005,53(4):893-898
A simple, rapid, and highly sensitive ion pair liquid chromatographic method for the determination of albendazole sulfoxide, albendazole 2-aminosulfone, and albendazole sulfone, which constitute the marker residue of albendazole in animal tissues (muscle, fat, liver, and kidney), is described. Tissue samples were extracted with acetonitrile, and the extracts were partitioned, as ion pairs, into dichloromethane. The organic layer was evaporated to dryness, and the residue was reconstituted in phosphate buffer and extracted with ethyl acetate. Separation was carried out isocratically with a mobile phase containing both positively and negatively charged pairing ions. Detection was performed fluorometrically, with excitation and emission wavelengths set at 290 and 320 nm, respectively. Overall recoveries were better than 76%, and the overall relative standard deviation was better than 7.3% in all tissues examined. The limits of quantification were 20, 1, and 0.5 ng/g for sulfoxide, 2-aminosulfone, and sulfone metabolites, respectively. The method was successfully applied to determine residues in tissues of two sheep orally administered an albendazole formulation. 相似文献
1000.
为建立大红甜橙的再生及遗传转化体系,提高转化芽的成株率,以30d龄的大红甜橙(CitrussinensisOsbeck)实生苗上胚轴为材料,导入rolB基因,进行遗传转化研究.结果表明:MS+3.0mg/L6-BA培养基诱导不定芽的效果最好,达95%以上.遗传转化时,采用培养基Ⅱ(MS+3mg/L6-BA+200μmol/LAs)+培养基Ⅳ(MT+3mg/L6-BA+50mg/LKan+500mg/LCef)组合的抗性芽诱导最快,诱导率为51%.用微芽嫁接的方法,将抗性芽嫁接到卡里佐枳橙上,成苗良好,已获得19株转rolB基因植株,盆栽在温室中生长良好. 相似文献