基于对外汉语教学的汉语动补式合成词分析     

朱红  梁英 《安徽农业大学学报》2014,(4):94-97

动补式合成词在汉语中是非常特殊的一类词语,在对外汉语教学中也是难点所在。对外汉语词汇教学需要依照汉语词汇大纲的要求,教师有必要对动补式合成词在汉语词汇大纲中的分布情况和汉语学习者在学习动补式合成词时的难点问题进行分析,并以此为依据制定切实可行的教学策略。研究发现四种动补式合成词在汉语词汇大纲中的分布情况有所差别,各个级别的汉语学习者在不同阶段也存在不同的难点问题,形成了不同教学阶段的重点,教师可以将各种有效的教学对策结合使用,以引导汉语学习者正确习得动补式合成词的意义和用法。  相似文献   

Multi-variable grey model (MGM (1,n,q)) based on genetic algorithm and its application in urban water consumption     

Yan Han　Shi Guoxu 《农业科学与技术》2007,8(1):14-20

Urban water consumption has some characteristics of grey because it is influenced by economy, population, standard of living and so on. The multi-variable grey model （MGM（1,n））, as the expansion and complement of GM（1,1） model, reveals the relationship between restriction and stimulation among variables, and the genetic algorithm has the whole optimal and parallel characteristics. In this paper, the parameter q of MGM（1,n） model was optimized, and a multi-variable grey model （MGM（1 ,n,q）） was built by using the genetic algorithm. The model was validated by examining the urban water consumption from 1990 to 2003 in Dalian City. The result indicated that the multi-variable grey model （MGM（1,n,q）） based on genetic algorithm was better than MGM（1,n） model, and the MGM（1,n） model was better than MGM（1,1） model.  相似文献   

血尔宝补铁蛋白咀嚼片对大鼠胚胎致畸作用的研究   总被引：2，自引：0，他引：2  

周文江  乔伟伟  杨丽萍  黄爱民  周佳来  杨幼明  戴秋萍 《上海交通大学学报(农业科学版)》2003,21(2):116-120

了解血尔宝补铁蛋白咀嚼片对SD大鼠胚胎的影响,将SD大鼠雌雄1:1交配,发现阴栓作为妊娠“零”天,检出的“孕鼠”随机分到阴性组、阳性组、高剂量组、中剂量组、低剂量组,并称重和编号。于妊娠第7～16d灌胃;受孕的0、7、12、16、20d称体重,并计算给受试物的量。孕鼠于妊娠20d处死,剖腹取子宫称重、取胎记录并检查胚胎、着床数、吸收胎、死胎和活胎数。活胎鼠记录胎仔体重、体长、尾长并检查胎鼠外观有无异常。半数活胎固定于鲍音氏液中固定两周后徒手切片作内脏检查,另半数活胎以茜素红作骨骼染色,并逐步检查骨骼。结果表示,20d孕鼠体重增长阳性组与阴性组、剂量组相比有显著差异(P<0.05);16d、20d孕鼠体重增长高剂量组与低剂量组相比有显著差异(P<0.05);各组相比着床总数无显著差异;活胎的仔数、吸收胎数、死胎数、平均仔重、体重、及尾长,阳性组与阴性组、剂量组相比有显著差异(P<0.05);阴性组、剂量组相比无显著差异(P>0.05);胚胎外形畸形率敌枯双阳性组为58.96%,与其它各组相比有显著差异(P<0.01)。阴性组和剂量组之间无显著差异(P>0.05)。表明血尔宝补铁蛋白咀嚼片对SD大鼠胚胎无致畸、毒性作用。  相似文献   

C1qa deficiency in mice increases susceptibility to mouse hepatitis virus A59 infection     

Han-Woong Kim  Sun-Min Seo  Jun-Young Kim  Jae Hoon Lee  Han-Woong Lee  Yang-Kyu Choi 《Journal of veterinary science (Suw?n-si, Korea)》2021,22(3)

BackgroundMouse hepatitis virus (MHV) A59 is a highly infectious pathogen and starts in the respiratory tract and progresses to systemic infection in laboratory mice. The complement system is an important part of the host immune response to viral infection. It is not clear the role of the classical complement pathway in MHV infection.ObjectivesThe purpose of this study was to determine the importance of the classical pathway in coronavirus pathogenesis by comparing C1qa KO mice and wild-type mice.MethodsWe generated a C1qa KO mouse using CRISPR/Cas9 technology and compared the susceptibility to MHV A59 infection between C1qa KO and wild-type mice. Histopathological and immunohistochemical changes, viral loads, and chemokine expressions in both mice were measured.ResultsMHV A59-infected C1qa KO mice showed severe histopathological changes, such as hepatocellular necrosis and interstitial pneumonia, compared to MHV A59-infected wild-type mice. Virus copy numbers in the olfactory bulb, liver, and lungs of C1qa KO mice were significantly higher than those of wild-type mice. The increase in viral copy numbers in C1qa KO mice was consistent with the histopathologic changes in organs. These results indicate that C1qa deficiency enhances susceptibility to MHV A59 systemic infection in mice. In addition, this enhanced susceptibility effect is associated with dramatic elevations in spleen IFN-γ, MIP-1 α, and MCP-1 in C1qa KO mice.ConclusionsThese data suggest that C1qa deficiency enhances susceptibility to MHV A59 systemic infection, and activation of the classical complement pathway may be important for protecting the host against MHV A59 infection.  相似文献   

利用一维代数模型分析微咸水入渗特征   总被引：1，自引：0，他引：1  

吴忠东  王全九 《农业工程学报》2007,23(6):21-26

由于淡水资源短缺，微咸水的开发利用成为缓解农业水资源短缺的重要措施，为了研究微咸水条件下的土壤入渗过程，进行了室内微咸水垂直一维入渗试验，分析了不同矿化度的微咸水累积入渗水量随时间的变化过程，并利用一维代数入渗模型模拟计算了土壤含水率剖面。结果表明：含水率模拟计算结果与实测值相吻合。同时利用一维代数入渗模型和Green-Ampt模型对试验资料进行处理，结果表明两模型均可以比较精确地描述微咸水入渗过程，因此两模型可以互相计算参数，但长历时入渗用Green-Ampt模型计算更加精确。  相似文献   

金黄色葡萄球菌SSL7蛋白对补体系统的作用分析   总被引：1，自引：0，他引：1  

邓亦宁  张云科  王朋朋  田欣睿  焦晓宇  吴文学 《中国农业大学学报》2021,26(9):146-153

为探究金黄色葡萄球菌超抗原样蛋白(Staphylococcal superantigen-like proteins,SSLs)与补体系统相关的生物学特征,利用原核表达系统表达SSL7重组蛋白,并通过补体杀伤试验、Western Blot以及Pull-down对其有关补体系统的生物学特征进行研究。结果表明:1)重组蛋白SSL7可在大肠杆菌感受态细胞BL21(DE3)系统中大量可溶性表达,大小约25ku;2)SSL7可阻断新鲜兔血清对大肠杆菌DH5α的补体杀伤作用;3)SSL7抑制补体激活后攻膜复合体(Membrane attack complex,MAC)的形成,新鲜兔血清无法在金黄色葡萄球菌NCTC 8325菌体表面形成MAC沉积;4)SSL7能捕获健康人血清(Human normal serum,HNS)中的补体C5,阻断补体系统的激活。综上,金黄色葡萄球菌超抗原样蛋白SSL7可以通过特异性结合补体C5阻断补体级联反应,逃避宿主免疫应答以达到致病的目的,为进一步探究SSL7的感染机制、揭示SSLs蛋白功能奠定基础。  相似文献   

玉米基因雄性不育双杂合保持系的选育研究   总被引：5，自引：2，他引：5  

季良越  罗福和 《作物学报》1993,19(3):262-267

本研究从1982年开始,选用玉米ms1、ms2和ms10三个雄性核不育基因以及易位断点与相应ms基因紧密连锁的T4-6b、T9-10a、T4-10f和T6-10（5519）四个易位系作为基础材料，采用细胞遗传技术育成若干个骨干自交系的基因雄性不育双杂合保持系。至今，已选育出黄早四和Mo17背景的ms2基因杂合保持系。保持系与ms2基因不育系杂交，子代  相似文献   

FMMU白化豚鼠与花色豚鼠血清Ig和补体含量及总补体活性比较     

李英  郭桂华  顾为望 《动物医学进展》2003,24(6):91-92

测定比较了 2月龄的封闭群 FMMU白化豚鼠与花色豚鼠的血清免疫球蛋白含量、补体含量及活性。结果表明 :白化豚鼠血清 Ig G含量极显著低于花色豚鼠 ,而 Ig A、Ig M含量显著低于花色豚鼠。白化豚鼠 C3含量极显著低于花色豚鼠 ,C4含量显著低于花色豚鼠。血清总补体活性 ( CH50 )显著低于花色豚鼠。  相似文献   

Neutralizing and Complement-fixing Monoclonal Antibodies as an Aid to the Diagnosis of Equine Herpesvirus-1 Infection     

Singh  B.K.  Yadav  M.P.  Tewari  S.C. 《Veterinary research communications》2001,25(8):675-686

One complement-fixing (C-MAb) and three complement-dependent neutralizing monoclonal antibodies (N-MAbs) were raised against Hisar-90-7 equine herpesvirus-1 (EHV-1) strain. The target antigen of the C-MAb (2A5) and two of the N-MAbs (1H6, 9C4) was identified as a 140 kDa polypeptide in Western blotting. The target antigen of N-MAb (9C6) could not be identified. Purified polypeptides of five EHV-1 strains isolated from different regions and at different times gave intense bands at 140 kDa when reacted with N-MAb (1H6) in Western blots. In sandwich ELISA, all four MAbs captured the viral antigen from clinical materials, giving a reliable and rapid diagnosis of EHV-1 infection in equines.  相似文献   

Cryopreservation of sheep red blood cells. 3. Complement titrations with frozen sensitized cells     

V Myhrvold 《Acta veterinaria Scandinavica》1979,20(4):537-545

The effect of different suspending and washing procedures for recovery of sensitized sheep erythrocytes (EA) after freezing at −196°C was investigated. Best results were obtained using gelatin-veronal-buffered saline-sucrose containing 0.15 mM-Ca and 1 mM-Mg (GVBSM⁺⁺-sucrose) as the suspending and first washing buffer. The cryoprotective agents tested were polyvinylpyrrolidone (PVP), neutralized PVP, purified PVP and a gum product, Avelex 1030. All PVP preparations tested gave good results as cryoprotectants in terms of cell recovery after thawing whereas Avelex 1030 was less satisfactory. The EA cells frozen in the presence of untreated PVP showed, however, increased susceptibility to the hemolytic action of complement, whereas cells frozen with purified or neutralized PVP gave titers similar to that obtained with fresh cells. Good results were also obtained with Avelex 1030. Complement titrations with frozen EA cells were more reproducible than titrations with fresh cells.  相似文献