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71.
The origin of the new A (H1N1) influenza virus recently emerging in North America is a hot controversial topic of significance in disease control and risk assessment. Some experts claimed that it was an unusually mongrelized mix of human, avian and swine influenza viruses, while some others concluded that it was totally a simple re-assortment hybrid of two lineages of swine influenza viruses. Here the phylogenetic diversity of the viral PB1, PA and PB2 gene sequences using online web servers, and the results suggest that all the 8 genetic segments of the new virus were possibly from two lineages of swine influenza viruses, and one of the lineage was a mongrelized mix of human, avian and swine influenza viruses emerging in the world approximately 10 years ago. Considering the recent epidemiological trends of the new virus, we believe it will spread more widely in the world and persist long in human populations. It also could spread among swine populations. The future wide spreading of the new virus may coincide the disappearance of a subtype of previous human influenza A virus.  相似文献   
72.
厌氧消化对养猪场废水的净化效果   总被引:1,自引:0,他引:1  
考察了不同水力停留时间下厌氧消化对养猪场废水水质(COD、NH4^+-N、TP和pH)的影响及装置产气量的变化.结果表明,厌氧消化对废水COD的去除效果较好,实验期内废水COD浓度持续下降,最终去除率为78.1%.但对NH4^+-N的去除效果不理想,最终去除率仅为1.8%,对废水TP的最终去除率为68.4%.  相似文献   
73.
A novel dual-label time-resolved fluoroimmunoassay method was developed for the simultaneous determination of chloramphenicol (CAP) and ractopamine (RAC) residues in 18 swine tissue samples, using anti-CAP and anti-RAC monoclonal antibodies labeled with europium (Eu3+) and samarium (Sm3+), respectively. The detection limits for CAP and RAC were 0.06 and 0.25 ng/g. The recovery from swine muscle samples was 102%–121% for CAP at spiking levels of 0.1–5 ng/g, and 69.8%–85.8% for RAC at spiking levels of 1–10 ng/g. The results obtained from the swine tissue samples using this method showed good agreement with those obtained using ELISA and GC-MS, with correlation coefficients (R) between 0.92–0.98.  相似文献   
74.
猪瘟是由猪瘟病毒感染导致的高度接触性传染病,家猪和野猪对该病原易感.该病主要特征是高热、微血管变性而引起实质器官出血、坏死,是世界上危害最严重猪病之一,给养猪业带来重大损失.综述了猪瘟病毒基因组、蛋白质功能以及致病机理的最新研究进展,为相关研究人员参考.  相似文献   
75.
使用辛酸沉淀-凝胶过滤法提取猪血清中免疫球蛋白IgM,并通过其纯度鉴定等探讨提纯效果.通过辛酸沉淀法粗提免疫球蛋白,再结合Sephadex G200凝胶过滤法纯化获得IgM,利用SDS-PAGE电泳法和AlphaEaseFC凝胶成像分析软件测定其分子量和纯度、Bradford法测定提取蛋白浓度并计算其得率.结果显示辛酸粗提能够去除大部分杂蛋白,凝胶过滤获得两个洗脱峰,其中第一峰通过电泳鉴定含有IgM,纯度63.8%,得率1.28 mg/ml血清.利用辛酸沉淀-凝胶过滤法能够获取纯度和得率都较高的IgM,纯度可满足普通要求的实验和应用.  相似文献   
76.
新型移动床生物膜反应器深度处理模拟养猪废水试验研究   总被引:2,自引:0,他引:2  
将新型移动床牛物膜反应器(moving bed biofilm reactor,MBBR)用于模拟养猪废水深度处理的试验,研究了反应器结构特征、水力停留时间(HRT)以及填料填充比对反应器处理效果的影响.通过优化反应器结构,实现了反应器内的功能分区,提高了反应器处理效率.MBBR用于模拟养猪废水深度处理的试验结果显示,新型MBBR反应器可实现模拟养猪废水中有机物和营养物的同步良好去除,在HRT为8 h,气水比12:1,填料填充比例为40%的条件下,化学耗氧量(COD),NH_4~+-N去除率达90%以上;同时实现了总氮(TN)的同步硝化反硝化(SDN)脱除,去除率达85%以上.  相似文献   
77.
为了研究猪PSMD13基因功能,采用SMART-RACE技术对猪PSMD13基因5′和3′端进行扩增,并对其进行序列分析和组织表达分析。结果表明,得到猪PSMD13基因全长1476bp的cDNA序列,其基因编码376个氨基酸,与人、小鼠、蛙、鲐鱼的PSMD13氨基酸序列分别有97%、94%、77%、85%的同源性,含有1个PINT保守结构域和1个类似的PCI domain结构域,无信号肽序列。组织表达分析结果表明,猪PSMD13在背最长肌、心脏、肝脏、脾脏、肺脏、肾脏、卵巢、子宫、睾丸、胚胎和脂肪等组织均有表达。  相似文献   
78.
Analysis of porcine MHC expression profile   总被引:2,自引:0,他引:2  
The porcine major histocompatibility complex (MHC, also named swine leukocyte antigen, SLA) is associated not only with immune responsibility and disease susceptibility, but also with some reproductive and productive traits such as growth rate and carcass composition. As yet systematical research on SLA expression profile is not reported. In order to illustrate SLA expression comprehensively and deepen our understanding of its function, we outlined the expression profile of SLA in 51 tissues of Landrace by analyzing a large amount of ESTs produced by ““Sino-Danish Porcine Genome Project““. In addition, we also compared the expression profile of SLA in several tissues from different development stages and from another breed (Erhualian). The result shows: (i) classical SLA genes are highly expressed in immune tissues and middle part of intestine; (ii) although SLA-3 is an SLA la gene, its expression abundance and pattern are quite different from those of the other two SLA la genes. The same phenomenon is seen in HLA-C expression, suggesting that the two genes may function similarly and undergo convergent evolution; (iii) except in jejunum, the antigen presenting genes are more highly expressed in breed Erhualian than in Landrace. The difference might associate with the higher resistance to bad conditions (including pathogens) of Erhualian and higher growth rates of Landrace.  相似文献   
79.
为建立鉴别猪流感病毒感染猪和灭活疫苗免疫猪的诊断方法,利用pET-28a载体在大肠杆菌BL21中表达H3N2 SIV河南株NS1,并通过Ni2+-NTA亲和色谱法纯化His-NS1融合蛋白.用SDS-PAGE,Western blotting和Dot-ELISA分析纯化蛋白,表明重组NS1能与猪流感病毒感染猪血清进行特异性反应,而不与灭活疫苗免疫猪血清反应.结果表明重组蛋白能作为区别猪流感病毒感染猪和灭活疫苗免疫猪的诊断抗原,为控制猪群中的流感病毒奠定了基础.  相似文献   
80.
应用逐步回归分析和正交优选方法,分析了冀东地区长汉约三元杂种猪8个数量性状与瘦肉率之间的回归关系,并通过稳定性检验证明:在合理的条件下,当胴体斜长和背膘厚取值越小,同时胴体直长、眼肌面积和后腿率取值越大时,则瘦肉率越高,并由试验找出了最优性状组合。  相似文献   
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