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181.
从江浙梅区所采10种梅树蚧虫中育得寄生蜂4科18属25种,其中3种为中国新记录,并有10项寄主新记录,文中登录了各种寄生蜂的名称、寄主和采地,对3个中国新记录种——长角短索蚜小蜂Archenomus longicornis(Nik),蜡蚧阔柄跳小蜂Metaphycus tamakatakaigara Tachikawa和网室优盾金小蜂Eunotus arelatus(Ratzeburg)作了记述,并附特征图。 相似文献
182.
183.
Keisuke SASAKI Hideo AIZAKI Michiyo MOTOYAMA Hideyuki OHMORI Tomoyuki KAWASHIMA 《Animal Science Journal》2011,82(1):175-180
Impressions and purchasing intentions of Japanese consumers regarding pork produced by ‘Ecofeed’, a trademark of food‐waste or co‐product animal feeds certified by the Japanese government, were investigated by a questionnaire on the Internet. ‘Ecofeed’ did not elicit specific impressions as compared to domestic, imported, Kurobuta (in Japan), and specific pathogen‐free (SPF) pork. Purchasing intent for ‘Ecofeed’ pork was the second lowest of the five pork products. Knowledge and purchasing experience regarding ‘Ecofeed’ pork was the lowest of the five pork products. Respondents were classified into four categories according to their impressions of ‘Ecofeed’ pork. The largest category of respondents did not have any specific impression of ‘Ecofeed’ pork and had little knowledge of pork farming. A category that had a positive impression for ‘Ecofeed’ pork had high knowledge of the pork farming system. In order to establish ‘Ecofeed’ pork in Japan, our results suggest that information disclosure and education about ‘Ecofeed’, its certification system, environmental benefits and the current self‐efficiency ratio of animal feed, are needed. 相似文献
184.
为建立稳定表达乙型脑炎病毒(JEV) NS1蛋白的真核细胞系,本研究将编码JEV NS1蛋白的人工合成基因克隆到真核表达载体pCAGG-TK-neo中,构建了重组质粒pCAGG-opti-NS1.重组质粒经脂质体转染RK-13细胞,以含G418的选择性培养基选择培养,经细胞克隆纯化,以间接免疫荧光试验(IEA)筛选表达目的基因的细胞.结果表明,转染的RK-13细胞经G418加压及IFA筛选后,获得表达JEV NS1蛋白的阳性RK-13细胞系.经RT-PCR、western blot和IFA鉴定,该细胞系在传代至第15代后仍然可以稳定表达NS1蛋白.本实验获得了能够稳定表达JEV NS1蛋白的细胞系,为进一步开展JEV相关的研究奠定了基础. 相似文献
185.
186.
猪瘟病毒、猪繁殖与呼吸障碍综合征病毒和乙型脑炎病毒多重RT-PCR检测方法的建立 总被引:1,自引:0,他引:1
根据猪瘟病毒(CSFV)的E2基因保守序列、猪繁殖与呼吸障碍综合征病毒(PRRSV)的ORF7基因及部分ORF6和3-UTR基因序列和猪乙型脑炎病毒(JEV)的E基因保守序列,设计了3对引物,扩增大小分别为288 bp、430 bp和1 015 bp目的片段.以纯培养病毒抽提RNA,制备cDNA模板,利用3对引物,通过条件的优化,建立了同时检测这3种病毒的多重RT-PCR.CSFV、PRRSV和JEV的RNA最小检出量分别为0.270 ng、0.049 ng、0.067 ng,其它的RNA病毒如TGEV以及DNA病毒如PPV、PrV、PCV-2检测结果为阴性.以β-actin为对照,利用本方法检测了174份临床样品(血清、肺脏和胎儿),其结果为:PRRSV、CSFV和JEV的阳性率分别为30.4%、4.6%和1.7%;CSFV和PRRSV混合感染阳性率为1.7%.同时对临床样品中CSFV、JEV和PRRSV阳性PCR产物进行测序分析,发现CSFV、PRRSV和JEV的PCR产物序列和NCBI数据库中目标基因的同源性分别为92%、90%和89%,这证实了多重PCR的阳性结果为上述3种病毒.结果证明,所建立的多重RT-PCR可用于临床检测. 相似文献
187.
Takeshi Shinogi Tomoko Suzuki Takayuki Kurihara Yoshihiro Narusaka Pyoyun Park 《Journal of General Plant Pathology》2003,69(1):7-16
Reactive oxygen species (ROS) generation was examined in the interaction of Alternaria alternata Japanese pear pathotype and host plants using three methods: nitro blue tetrazolium (NBT) method for microscopic detection
of O2
−, diaminobenzidine (DAB) methods for microscopic detection of H2O2, and cerium chloride methods for ultrastructural detection of H2O2. ROS generation was detected by NBT and DAB methods at appressoria on leaves of susceptible cultivars and heat-shocked leaves
of resistant cultivars but not in leaves of resistant cultivars. Ultrastructural detection by the cerium chloride method identified
ROS generation at cell walls of appressoria and penetration pegs in susceptible, resistant leaves and heat-shocked leaves.
These differences in the ultrastructural and microscopic data in resistant areas were due to the restriction of ROS generation
in limited areas, the side facing the plant surface, of appressoria and penetration pegs. Therefore, ROS generation was apparently
induced regardless of the resistance or susceptibility of the cultivar with the difference being in the volumes generated.
After evaluating the pathological role of ROS generation in fungal structures, such generation was found to be associated
with early penetration of cell walls in pear plants. Additionally, ROS generation in plants was also found in degrading pectin
layers near infected hyphae and in plasma membrane modification sites in susceptible leaves but not in resistant leaves. ROS
generation in susceptible leaves might be accompanied with plasma membrane damage, although the role of ROS generation in
the pectin layers is not clear. ROS generation in both fungal and plant cells during their interaction was likely associated
with the expression of susceptibility.
Received: June 3, 2002 / Accepted: July 31, 2002 相似文献
188.
为了比较3种扇贝血液中的K+、Na+、Ca2+和Cl−浓度,血氧(pO2)和血二氧化碳(pCO2)气体分压及血液酸碱度(pH)的差异情况,实验利用血气分析仪对栉孔扇贝、虾夷扇贝和海湾扇贝的血液生理指标进行测定。结果显示,扇贝的血液生理指标呈现显著的物种差异,其中栉孔扇贝血液的K+浓度[(15.74±1.47) mmol/L]、Na+浓度[(388.07±11.38) mmol/L]、Cl−浓度[(462.43±6.88) mmol/L]和pO2 [(140.13±15.35) mmHg]最高。此外,栉孔扇贝和虾夷扇贝的Ca2+浓度和pCO2含量较高,而海湾扇贝的pH最高。对相同月龄不同大小栉孔扇贝血液指标进行比较,发现栉孔扇贝的血液pH值与其壳高呈正相关(r=0.611),而生理指标与壳高呈负相关。随着温度的升高,栉孔扇贝血液的Ca2+浓度显著增加,而pO2显著下降,K+、Na+和Cl−浓度先升高后恢复到初始水平,而pH和pCO2保持相对稳定。研究结果为贝类血液生理研究提供参考,也为贝类生理状态的评估提供了一种新的思路与方法。 相似文献
189.
虾夷扇贝体形性状对软体重和闭壳肌重的影响效果分析 总被引:4,自引:3,他引:4
利用虾夷扇贝表型性状资料,分析性状间的相关关系及其相关程度,建立相应的回归方程,为扇贝的选择育种奠定基础。试验随机抽取126只体形规则的3龄大连獐子岛海区底播增殖的虾夷扇贝,其中雌雄各63只,测定其壳长(X1)、壳高(X2)、壳宽(X3)、活体重(Y)、软体重(Z)和闭壳肌重(W),分别计算相关系数,采用通径分析方法计算了以体形性状为自变量对软体重和闭壳肌重作依变量的通径系数、决定系数及相关指数,定量的分析了体形性状对虾夷扇贝解剖性状的影响。结果表明虾夷扇贝壳长、壳宽、壳高与活体重、软体重和闭壳肌重的相关系数均达到极显著水平(P<0.01);壳高、壳宽是影响雌性软体重的主要因素,壳长、壳宽是影响雄性软体重的主要因素,而混合组受3个壳尺性状的共同影响;影响虾夷扇贝闭壳肌重的主要因素是壳宽,壳长、壳高的作用不显著;决定系数分析结果与通径分析结果有一致的变化趋势;多元回归分析,剔除不显著因子,建立了壳长、壳高、壳宽对软体重、闭壳肌重的回归方程:1). 雌性 Z= -128.573 +1.355X2 +1.407 X3;W= -8.216 +0.869X3;2). 雄性 Z =138.493+1.082 X1+2.524 X3;W= -11.855 + 0.955 X3;3). 混合 Z = -133.939 +0.606 X1+0.679X2 + 1.709X3;W= -9.525+ 0.896 X3。通过性状间的相关分析对两性状间的关系进行明确的定量,有利于制定合理的多性状选择方案,为虾夷扇贝选育提供理想的测度指标。 相似文献
190.
Kazufumi?OsakoEmail author Mohammed?Anwar?Hossain Koichi?Kuwahara Akira?Okamoto Atsuko?Yamaguchi Yukinori?Nozaki 《Fisheries Science》2005,71(6):1347-1355
ABSTRACT: To explore the potential utility of underutilized fish in the fish sauce industry, fish sauces were prepared from both raw and heat-induced meat of Japanese anchovy Engraulis japonica and rabbit fish Siganus fuscescens using wheat malt, and their quality aspects and sensory properties were assessed. Proximate composition of the fish meat represents protein as the major component (16.0–17.8%), other than moisture. Analyses of free amino acids, peptides including oligopeptides, and organic acids contents in fish sauces revealed suitability of both raw and heat-induced meat of the selected species in commercial fish sauce production. The variations in taste of raw meat fish sauces were species-specific, but the taste of fish sauces from heat-induced meat were similar. 相似文献