H3N2亚型犬流感病毒HA1基因的原核表达及抗原性分析

为原核表达H3N2亚型犬流感病毒(CIV)HA1蛋白,本研究利用特异性引物扩增CIV H3分离株的HA1基因,将其克隆到pMD18-T载体后进行序列测定。再将其亚克隆于pET-32a(+)中构建重组表达质粒pET-HA1。将该质粒转化于大肠杆菌BL21(DE3)中,经IPTG诱导,SDS-PAGE电泳分析,表达的重组蛋白约为58 ku。纯化的HA1蛋白经western blot和Dot-ELISA鉴定表明,表达的重组HA1蛋白可以与H3N2亚型CIV阳性血清发生特异性反应。     

Pedo‐ecological consequences of lithological discontinuities in soils—examples from Central Europe

Soil profiles having lithological discontinuities, i.e., stratified or layered profiles, occur worldwide. Their genesis as part of the upper‐regolith formation is comparatively well understood, particularly in Central Europe where extensive research on relic periglacial cover beds has been done. But the pedogenetic and ecological implications of lithologically discontinuous soils (LDS) are less well known. Most textbooks rely on the so‐called A‐B‐C‐model as a climate‐driven approach to soil formation. After reviewing definitions and concepts of lithological discontinuities and how they form, we present a pedogenetic model extending the traditional approach by considering substrate genesis and regolith dynamics. The consequences in the interpretation of vertical distributions of parameters of soil acidification and of heavy metals are investigated for typical soil profiles from the W Ore Mountains and the central‐German lowlands. Results show how lithological discontinuities influence the depth gradients and that properties inherited from substrate should be distinguished, if possible, from those developed by pedogenesis.     

Development of NMR and raman spectroscopic methods for the determination of the degree of substitution of maleate in modified starches.

In this paper we report the application of NMR spectroscopy and Raman spectroscopy to determine the degree of maleate substitution in maleinated starches. Five kinds of maleinated starches were investigated and calibration sets were constructed to derive linear regression equations that may be used to predict the degree of maleate substitution for starch samples with unknown amounts of chemical modification. The calibration sets reported have very high linearity (r > 0.99) for both the NMR and Raman methods. The NMR and Raman calibration sets allow fast and nondestructive measurement of the degree of maleate substitution for different starches with little need of sample preparation.     

High pressure liquid chromatographic determination of zearalenone in chicken tissues

A method is reported for the extraction and analysis of zearalenone in chicken fat, heart muscle, and kidney tissue by using high pressure liquid chromatography (HPLC). Zearalenone is extracted with acetonitrile, cleaned up with hexane, and extracted further with ethyl acetate. Zearalenone is determined by HPLC using a reverse phase radial compression separation system, an ultraviolet absorbance detector, and a mobile phase of acetonitrile-water (60 + 40) (v/v). Recoveries of zearalenone added at levels from 50 to 200 ng/g are in the range 82.6-95.1%.     

Diurnal migration and responses to simulated rainfall in desert soil microarthropods and nematodes

Diurnal patterns of microarthropod abundance in surface leaf litter were related to its moisture content. Leaf litter moisture was nearly 7% by weight at 0800h but fell to less than 1% by mid-day. Oribatid and tydeid mites moved into litter in the early morning and back into the soil before mid-day. There were no significant differences in numbers of nematodes in litter or soil and 78–98% of the nematodes were anhydrobiotic (coiled) in soil and litter at all times sampled.Following simulated rainfall there were fewer microarthropods in litter at mid-day in the absence of marked decreases in soil and litter moisture content. During drying, there were gradual reductions in numbers and species diversity of litter microarthropods. Nematode numbers did not change as litter dried. Anhydrobiotic nematodes in the soil increased from 14% on day 1 to 85% on day 4. Between 24 and 36 h after simulated rainfall, the proportion of anhydrobiotic litter nematodes increased from 35 to 80%,.Within 1 h after simulated rainfall, there were marked increases in numbers and diversity of microarthropods in surface litter. No collembolans were extracted from dry litter controls but the wet litter was dominated by isotomid, sminthurid and onychiurid collembolans. There were increases in numbers and diversity of oribatid, tydeid and gamasid mites in the wet surface litter within l h after wetting compared to controls.     

BILATERAL OVARIAN ADENOCARCINOMA IN A DOG: ULTRASONOGRAPHIC-AIDED DIAGNOSIS

Abdominal ultrasonography was instrumental in the diagnosis of bilateral ovarian adenocarcinoma in a twelve year old female Irish Setter. Severe ascites limited the diagnostic quality of abdominal radiography, but enhanced ultrasonographic images. Ultrasonographically, the ovarian tumors were large, contained multiple anechoic cystic structures, and had irregular margins. The ultrasonographic appearance of ovarian adenocarcinoma has not been previously reported.