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食用菌深层培养是为了适应工业化生产而设计的一项新型技术,深层液体培养食用菌种取代传统的瓶栽菌种不仅适应了工业化生产的需要,而且流程快、用料省,不失为是一种发展食用菌生产的一条新路子。本文根据国外近年来液体深层培养的研究情况,加以综述,供参考。 相似文献
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从母牛接种过A组BRV株NCDV-Lincoln(P1:G6)苗的两个吡邻牛场分离到两株牛轮状病毒(BRV),编号为NS-1和NS-2,Northern-blotting试验表明,NS-1和NS-2有相的的A组RNA电泳模式,而且全部基因片段同源,体外中和试验表明,NS-1株病毒能被G6特异性单克隆抗体(McAs)和抗BRVB641株(P5:G6)豚鼠高免血清(GPAS)中和,但不被G10特异性M 相似文献
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The H7N2 subtype of avian influenza virus (AIV) field isolate (H7N2/chicken/PA/3779-2/97), which caused the 1997-98 AIV outbreak in Pennsylvania, was evaluated for its infectivity, length of infection, and immune response in specific-pathogen-free (SPF) chickens. The composite findings of three clinical trials with various concentrations of virus indicated that this H7N2 subtype contained minimal pathogenicity for chickens. The concentration of the virus in the inoculum proved critical in the establishment of a productive infection in a chicken. Seven-day-old SPF chickens were not infected when inoculated with 10(0.7-2.0) mean embryo lethal dose (ELD50) of the H7N2 virus per bird. At this dose level, the immune response to this virus was not detected by the hemagglutination-inhibition (HI) test. Nonetheless, chickens at ages of 5 and 23 wk old tested were successfully infected when exposed to 10(4.7-5.7) ELD50 of H7N2 infectious doses per bird by various routes of administration and also by direct contact. Infected birds started shedding virus as early as 2 days postinoculation, and the period of virus shedding occurred mostly within 1 or 2 wk postinoculation (WPI). This H7N2 subtype of AIV induced a measurable immune response in all birds within 2 wk after virus exposure. Antibody titers were associated with AIV infectious doses and age of exposure of birds. Challenge of these infected birds with the same H7N2 virus at 5 and 10 WPI indicated the infective virus was recoverable from cloacal swabs at 3 days postchallenge and disappeared thereafter. In these challenged birds, the antibody levels as measured by the HI test spiked within 1-2 wk. 相似文献
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A seven-month-old, male ferret had acute paraplegia and radiographs showed signs of disc prolapse between the second and third lumbar vertebrae (L2/3). Hemilaminectomy was performed to decompress the spinal cord. Histological examination revealed that the extradural material was consistent with annulus fibrosus and the L2/3 articular facets were enlarged as a result of bone remodelling. The ferret became ambulatory one month postoperatively. Five months postoperatively, the ferret had normal posture with mild proprioceptive deficits in the pelvic limbs, and fusion of the L2 and L3 vertebral bodies. 相似文献
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A random 12-peptide library was used to screen immunodominant mimics of 99kDa iron-regulated outer membrane protein (IROMP-99) of rabbit Pasteurella multocida. In the present study, expression of IROMPs of rabbit P. multocida strain C51-12 were analyzed by SDS-PAGE, and Western blot to determine the specificity of rat antiserum antibodies against IROMP-99. Only IROMP-99 whose expression was induced under iron-restricted conditions was detected on nitrocellulose paper. The phage display library was screened with rat normal and IROMP-99-specific antiserum. The positive phage clones were identified using enzyme-linked immunoadsorbent assay (ELISA) and inhibition assays for their reactivity to the antiserum. Out of the 18 randomly selected positive clones that showed higher reactivity to rat antiserum, only ten clones efficaciously inhibited binding of rat antisera to IROMPs and their displayed peptides were determined. Alignment using DNAStar-MegAlign software, results showed that motif WHxTxP was highly conserved among nine clones, only clone A7 had no obvious linear homology with either. Our findings suggest that the motif WHxTxP could be an immunodominant mimic epitope of IROMP-99 of rabbit P. multocida strain C51-12. 相似文献
110.
Lu HP 《Science (New York, N.Y.)》2012,335(6066):300-301