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91.
为探讨重组鸡白介素18(mChIL-18)毕赤酵母工程菌在5L发酵罐中大规模发酵的工艺及其对新城疫疫苗的免疫增强作用,复苏工程菌GS115/pPIC9K-mChIL-18于YPD培养基,在其D600值达到5.2左右时转入发酵罐中,采用分批补料方式对毕赤酵母工程菌进行高密度发酵。控制和优化各种发酵条件,经历84h结束发酵。将发酵液离心,用6×His镍柱对上清中的表达产物进行纯化,并将纯化后的mChIL-18用脂质体包被后和新城疫疫苗一起对鸡群免疫。结果显示,毕赤酵母工程菌在5L发酵罐采用甲醇诱导补料批式发酵,在pH5.5,溶氧值20%~30%,温度28℃,诱导72h,mChIL-18的表达产量为560mg/L,发酵上清经纯化后纯度可达70%以上;用0.2mL的mChIL-18脂质体能够显著增强机体的免疫力,其中HI抗体效价和淋巴细胞亚群CD4+、CD8+含量均显著高于对照组。这表明mChIL-18毕赤酵母工程菌在5L发酵罐高密度发酵成功,并能显著增强新城疫疫苗的免疫效果,为IL-18在生产实践得到更好的应用奠定了基础。 相似文献
92.
Leaf shapes are not only the useful indicators in plant taxonomy,but also the important factors affecting energy and material exchange in leaves.In this paper,we collected and scanned the leaves of Nitraria tangutorum in Dengkou of Inner Mongolia Autonomous Region(the mean annual precipitation 145 mm) and Minqin of Gansu Province (the mean annual precipitation 115 mm) and N. sphaerocarpa in Dunhuang,and then analyzed leaf shape parameters with Image - Pro Plus6.0 image processing software and leafδ13C values in the isotope laboratory of the Chinese Academy of Forestry.The result showed that:1) as leaf area increased with increasing water availability the increases in the leaf length and width were asynchronously;2) with the same leaf width,the 1 eaves of N.tangutorum and N.sphaerocarpa were significantly longer in high water available conditions;and 3) although there were significantly differences in water availability between Dengkou and Minqin,as well as between the bottom and middle of the alluvial fan near the East Lake in Dunhuang,the leafδ13C values of N.tangutorum or N.sphaerocarpa were similar in different water conditions(P>0.05).Our results suggested that the ratio of leaf perimeter to area would be an important factor which linked leaf shape to plant water physiology.During growing procedure of leaf area,leaf length increase was prior to its width to alleviate the reduction in ratio of perimeter to area and maintain water use efficiency of the plant. 相似文献
93.
为了探究性腺激素作用下山羊子宫内膜上皮细胞(EEC)中白细胞介素-18(IL-18)的分泌活性,以及子宫内膜基质细胞(ESC)对其分泌活性的调节作用。基于套皿共培养永生化山羊EEC和ESC为体外研究模型,通过ELISA和Western blot方法检测E2和/或P4对EEC中IL-18分泌水平的作用以及ESC对该作用的影响。ELISA结果显示,E2较无激素对照组可显著增强单独培养EEC中IL-18的分泌水平(P〈0.05),P4单独或与E2联合作用则进一步增强其分泌活性(P〈0.01);EEC与ESC共培养模式下,ESC细胞对性激素作用下EEC中IL-18分泌活性具有显著的抑制作用。Western blot结果显示,在单独培养或与ESC共培养模式下,EEC培养上清液中IL-18均以相对分子质量大小18 300的具有生物活性的蛋白形式存在。本研究结果表明,山羊ESC对性腺激素作用下EEC中IL-18的分泌活性具有重要调节作用。 相似文献
94.
Leblanc AK Miller AN Galyon GD Moyers TD Long MJ Stuckey AC Wall JS Morandi F 《Veterinary radiology & ultrasound》2012,53(3):348-357
Palladia(TM) (toceranib phosphate-Pfizer Animal Health) is a novel orally administered receptor tyrosine kinase inhibitor (TKI) approved for treatment of canine mast cell tumors. Receptor tyrosine kinase dysregulation leads to tumor growth, progression, and metastasis. Toceranib's targets include vascular endothelial growth factor receptor (VEGFR-2/Flk-1/KDR), platelet-derived growth factor receptor, and kit. Positron Emission Tomography/Computed Tomography (PET/CT) is used commonly to diagnose, prognosticate, and monitor response to antineoplastic therapy in human patients. In this study, serial PET/CT imaging with (18) F-fluorodeoxyglucose ((18) FDG) was used to assess response to toceranib therapy in dogs with measurable solid malignancies. Six tumor-bearing dogs underwent tumor assessment using both standard RECIST criteria and PET/CT prior to and at a median of 5 weeks postinitiation of toceranib treatment. Toceranib was prescribed initially at a target dose 3.25 mg/kg PO q48 h, with subsequent modifications based on observed toxicity. Treatment was continued in patients achieving stable disease with acceptable drug tolerance. One dog was maintained on drug despite dose modification due to toxicity; measurable clinical and image-based responses were seen after 10 weeks of therapy. All others had stable or progressive disease based on clinical restaging and PET/CT at first recheck. . Due to discordance with anatomic and metabolic imaging, further studies are needed to investigate the role of molecular imaging in assessment of drug response and identify other potential molecular targets of toceranib. 相似文献
95.
在广东省深圳市薇甘菊为害严重的地区设置样地,用18%2,4-滴微乳剂不同浓度进行除治试验,结果表明:400~800倍液为有效浓度,1 000~1 200倍液为有效低浓度。不同生境样地防除试验结果表明:在山坡林地带可选用400~600倍液,在丘陵植被地带和果树周边地带可选用500~800倍液,在水塘、水库、水源周边地带以及菜地、花卉、药材和植物保护区周边地带可选用800倍液以下的有效低浓度。 相似文献
96.
建立了一种用C18键合磁珠固相萃取虾肉中氯霉素残留的方法。在Fe3O4超顺磁性纳米颗粒的表面键合C18基团,制备双功能反相萃取颗粒。用该颗粒对样品中的氯霉素残留进行固相萃取,对结合时间、温度、磁珠用量等因素进行了优化,建立磁珠法兽药残留固相萃取方法。用标准方法(SN/T 1864-2007)对萃取所得产物进行检测。经过优化,C18键合磁珠的最佳萃取条件为50℃结合5 min,用1 mL甲醇洗脱3次。检测结果显示该方法具有良好的精密度和回收率。在0.1~10μg/kg之间具有良好的线性关系,相关系数为0.9941,检出限为0.1μg/kg。该方法灵敏度高、重现性好、准确度高,可满足虾肉中氯霉素残留检测的需要。 相似文献
97.
98.
测定了茂兰喀斯特森林内的荔波野生梅(Prunus mume Sieb.et Zucc)叶片的δ13C值,同时对不同生境的荔波野生梅叶片的δ13C值进行比较,结果表明,荔波野生梅叶片δ13C值的范围为-29.43‰~-26.50‰,平均值为-28.00‰±0.71‰,比典型的亚热带植物要高,δ13C值变化范围也较亚热带地区更大,但与报道的喀斯特山区植物的叶片δ13C值相近;不同生境的荔波野生梅叶片δ13C值存在显著差异,石面和石缝生境的平均值显著低于土面生境的平均值,但石面和石缝生境间不存在显著差异;土壤的含水量对植物叶片δ13C值的高低有较大的影响,它们之间呈显著的负相关,R值为-0.72. 相似文献
99.
Karen Gibb Jennifer Beard Peter OReagain Keith Christian Valeria Torok Kathy Ophel-Keller 《Pedobiologia》2008,51(5-6):445-461
An urgent need exists for indicators of soil health and patch functionality in extensive rangelands that can be measured efficiently and at low cost. Soil mites are candidate indicators, but their identification and handling is so specialised and time-consuming that their inclusion in routine monitoring is unlikely. The aim of this study was to measure the relationship between patch type and mite assemblages using a conventional approach. An additional aim was to determine if a molecular approach traditionally used for soil microbes could be adapted for soil mites to overcome some of the bottlenecks associated with soil fauna diversity assessment. Soil mite species abundance and diversity were measured using conventional ecological methods in soil from patches with perennial grass and litter cover (PGL), and compared to soil from bare patches with annual grasses and/or litter cover (BAL). Soil mite assemblages were also assessed using a molecular method called terminal-restriction fragment length polymorphism (T-RFLP) analysis. The conventional data showed a relationship between patch type and mite assemblage. The Prostigmata and Oribatida were well represented in the PGL sites, particularly the Aphelacaridae (Oribatida). For T-RFLP analysis, the mite community was represented by a series of DNA fragment lengths that reflected mite sequence diversity. The T-RFLP data showed a distinct difference in the mite assemblage between the patch types. Where possible, T-RFLP peaks were matched to mite families using a reference 18S rDNA database, and the Aphelacaridae prevalent in the conventional samples at PGL sites were identified, as were prostigmatids and oribatids. We identified limits to the T-RFLP approach and this included an inability to distinguish some species whose DNA sequences were similar. Despite these limitations, the data still showed a clear difference between sites, and the molecular taxonomic inferences also compared well with the conventional ecological data. The results from this study indicated that the T-RFLP approach was effective in measuring mite assemblages in this system. The power of this technique lies in the fact that species diversity and abundance data can be obtained quickly because of the time taken to process hundreds of samples, from soil DNA extraction to data output on the gene analyser, can be as little as 4 days. 相似文献
100.
This study aimed to determine the prevalence and species of Cryptosporidium among HIV/AIDS patients in southwest of Iran. Two hundred fifty faecal samples from HIV patients were examined for the presence of Cryptosporidium oocysts using a conventional coproscopic approach. Such oocysts were detected in 18 (7.2%) out of 250 faecal samples. Genomic DNAs from 250 samples were then subjected to a nested-PCR-RFLP technique targeting different loci of 18S rRNA gene for species identification. Out of 250 samples, 27 (10.8%) were positive for different Cryptosporidium spp; Restriction patterns resulting from the digestion of the nested amplicon with restriction endonucleases VspI and SspI showed that C. parvum (70.38%) was the most prevalent species, followed by C. hominis (25.92%) and C. meleagridis (3.7%), respectively. The mean CD4+ T-cell count was 215 cells/μL. There was a strong association between cryptosporidiosis and CD4+ T-cell count (P = 0.000) with the highest prevalence recorded among patients with CD4+ T-cell count < 200 cells/μL. This confirms that there is a low opportunity for this parasite to get established as the patients CD4+ T-cell count increases. Also HIV infection increased the risk of having Cryptosporidium. Our epidemiological findings are useful for any preventive intervention to control disease diffusion. 相似文献