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991.
本试验分别用蛋白G亲和层析法、饱和硫酸铵法和辛酸-硫酸铵法纯化兔抗H9N2亚型禽流感病毒血清,发现蛋白G亲和层析法纯化得到的抗体纯度最高,回收率较低,抗体活性未变,操作简便,但成本较高,适合实验室研究及小量样品的纯化;饱和硫酸铵法纯化得到的抗体纯度较蛋白G亲和层析法低一些,抗体活性不变,可通过多次盐析来提高抗体纯度,多作为蛋白G亲和层析法纯化前的初步纯化;辛酸-硫酸铵法纯化得到的抗体纯度不及前两种方法,回收率较高,抗体活性亦无改变,纯化时对pH的精确性和辛酸的浓度要求较高,多用于样品的粗提和单抗的纯化。  相似文献   
992.
油菜新品种高油9号特征特性及其高产栽培技术   总被引:6,自引:0,他引:6  
高油9号油莱是山西省农业科学院高寒区作物研究所以蒙1008为母本。怀仁黄芥为父本进行有性杂交选育而成的高产、优质芥菜型春油菜新品种,2006年通过山西省农作物品种审定委员会审定。2003-2004年在山西省生产试验中,高油9号平均产量1452kg/hm^2.比对照晋油6号增产5.8%。高油9号合油量33.1%,油酸含量41.6%,亚油酸含量29.9%,芥酸含量1.1%,是一个低芥酸优质春油莱新品种。经过几年的栽培试验,已总结出高油9号油菜配套高产栽培技术。  相似文献   
993.
考察发酵培养基组分对纤维杆菌X4-9发酵产葡聚糖内切酶、葡聚糖外切酶和β-葡萄糖苷酶的影响。应用DPS软件的二次回归旋转中心组合实验设计方法,对纤维杆菌X4-9的发酵培养基(花生秸杆粉、蔗糖、尿素、(NH4)2SO4、硫酸镁、磷酸二氢钾)进行了优化。结果表明:在试验数值范围内,花生秸杆粉、蔗糖和(NH4)2SO4对酶活均会产生极显著的正效应,而尿素、硫酸镁和磷酸二氢钾的用量则具有明显的负效应;在优化的发酵培养基配方(花生秸杆粉30 g/L、蔗糖20 g/L、尿素2.5 g/L、(NH4)2SO4 10 g/L)下,葡萄糖内切酶、葡聚糖外切酶和β-葡萄糖苷酶的酶活分别达到2.705163,5.723014和3.614921 I U/mL,比初始发酵培养基配方下的各酶活分别提高了123.66%,146.32%和186.40%。纤维杆菌X4-9均能同时产生葡萄糖内切酶、葡聚糖外切酶、β-葡萄糖苷酶等纤维素降解复合酶系,且这些酶高产的培养基条件较为一致。  相似文献   
994.
Miao FP  Li XD  Liu XH  Cichewicz RH  Ji NY 《Marine drugs》2012,10(1):131-139
Two new compounds, asperversin A (1) and 9ξ-O-2(2,3-dimethylbut-3-enyl)brevianamide Q (2), and nine known compounds, brevianamide K (3), brevianamide M (4), aversin (5), 6,8-di-O-methylnidurufin (6), 6,8-di-O-methylaverufin (7), 6-O-methylaverufin (8), 5α,8α-epidioxyergosta-6,22-dien-3β-ol (9), ergosta-7,22-diene-3β,5α,6β-triol (10), and 6β-methoxyergosta-7,22-diene-3β,5α-diol (11), were obtained from the culture of Aspergillus versicolor, an endophytic fungus isolated from the marine brown alga Sargassum thunbergii. The structures of these compounds were established by spectroscopic techniques. Compounds 4, 7 and 8 exhibited antibacterial activities against Escherichia coli and Staphyloccocus aureus, and 7 also showed lethality against brine shrimp (Artemia salina) with an LC50 value of 0.5 μg/mL.  相似文献   
995.
甬优9号2010年在福建延平区大横镇多点试种,表现高产、优质、抗倒、较抗病等特点。栽培上要注意科学确定播种期,控制秧龄,合理密植和肥水管理,早防病虫害,足黄收割,才能保证高产优质。  相似文献   
996.
籼型水稻三系不育系楠丰9A的选育和应用研究   总被引:3,自引:1,他引:2  
卢华金  杨文清  楼珏  阮柏苗  郑国楚  陈国光  洪德林 《安徽农业科学》2011,39(28):17198-17200,17205
楠丰9A是温州市农业科学研究院选育的中籼野败型三系不育系。该不育系不育性稳定,花粉败育率99.99%,典败率97.53%;柱头紫色,午前花占67.0%,柱头总外露率71.62%,其中双外露率30.95%;株型适中,分蘖力强,穗大粒多;配合力强,穗数、穗总粒数非加性效应显著,株高、结实率则有一定负面作用;高胶稠度,中低直链淀粉含量,中感稻瘟病和白叶枯病。2009年通过浙江省农作物品种审定委员会技术鉴定。  相似文献   
997.
中国于2013年底首次发现H10N8亚型禽流感病毒(AIV)能感染人并致死的病例,而在此之前从未有过关于H10N8亚型病毒能感染人的报道,目前也未在其他国家监测到H10N8亚型AIV感染人的病例。与H7N9亚型AIV相似,H10N8亚型AIV在家禽中致病性很弱,可一旦感染人能表现出很强的致病性。感染了H10N8亚型AIV的患者病情恶化快、死亡率高、对人的健康危害很大,但至今尚无有效的防制手段。目前还不太清楚H10N8亚型AIV是通过何种途径传播给人的,今后H10N8亚型AIV是否会在人群中引发新的疫情暴发是人们普遍关心的问题。文章简要介绍了H10N8亚型AIV的特点及研究现状。  相似文献   
998.
Three species of fruit flies cause serious damage to cucurbit crops on Reunion Island: Bactrocera cucurbitae (Diptera: Tephritidae) (Coquillett 1899), Dacus ciliatus (Loew 1901), and Dacus demmerezi (Bezzi 1917). To control them, a program of agroecological management of cucurbit flies has been implemented based on the application of Synéis-appât, especially spot sprays on corn borders. However, the high rainfall on Reunion Island limits the long-term efficiency of the bait; in addition, this method cannot be used for large chayote trellises, because corn borders cannot be planted around them. The aim of this study was to design a bait station adapted to prevailing conditions on Reunion Island. An ‘umbrella trap’ tested in Taiwan was used as a reference to compare its efficacy with our local bait station. Experiments were conducted in field cages on B. cucurbitae to test different characteristics of bait stations and to construct one using local materials. Results were validated in the field. The attractiveness of the bait station was related mainly to the color of the external surface, yellow being the most attractive color. The efficacy of the bait station with respect to fly mortality was found to be linked to the accessibility of the bait, and direct application of Synéis-appât on the bait station was found to be the most efficient. In the field, B. cucurbitae were more attracted to the local bait station than to the umbrella trap, while the two other fly species displayed equal attraction to both trap types. Our local bait station is a useful alternative to spot sprays of Synéis-appât and is now included in a local pest management program and is well accepted by farmers.  相似文献   
999.
Cnaphalocrocis medinalis Güenée can cause severe losses in rice. Cytochrome P450s play crucial roles in the metabolism of allelochemicals in herbivorous insects. Two novel P450 cDNAs, CYP6CV1 and CYP9A38, were cloned from the midgut of C. medinalis. CYP6CV1 encodes a protein of 500 amino acid residues, while CYP9A38-predicted protein has 531 amino acid residues. Both cDNA-predicted proteins contain the conserved functional domains for all P450s. Phylogenetic analyses showed that CYP6CV1 is grouped in the cluster containing CYP6B members, while CYP9A38 is in the cluster including CYP9 members. However, both clusters are contained in the same higher lineage. Homologous analysis revealed that CYP6CV1 is most similar to CYP6B8, CYP6B7, CYP6B6, CYP6B2, and CYP6B4 with the highest amino acid identity of 41%. CYP9A38 is closest to CYP9A17, CYP9A21, CYP9A20, and CYP9A19 with the highest amino acid identity of 66%. Studies of temporal expression profiles revealed that CYP9A38 showed a steady increase in mRNA level during the five instar stages, but a low-expression level in pupae, and then presented at a high-expression level again in adults. Similar expression patterns were obtained with CYP6CV1. In the fifth instar larvae, CYP6CV1 was mainly expressed in midgut and fat bodies, whereas CYP9A38 was mainly expressed in midgut. Expression studies also revealed a 3.20-fold over-expression of CYP6CV1 and 3.54-fold over-expression of CYP9A38 after larval exposure to host rice resistance. Our results suggest that both CYP6CV1 and CYP9A38 may be involved in detoxification of rice phytochemicals.  相似文献   
1000.
Intermittent hypobaric hypoxia (IH) is linked with oxidative stress, impairing cardiac function. However, early IH also activate cardio-protective mechanisms. Omega 3 fatty acids (Ω3) induce cardioprotection by reducing infarct size and reinforcing antioxidant defenses. The aim of this work was to determine the combined effects of IH and Ω3 on cardiac function; oxidative balance and inflammatory state. Twenty-eight rats were randomly divided into four groups: normobaric normoxia (N); N + Ω3 (0.3 g·kg−1·day−1); IH; and IH + Ω3. IH was induced by 4 intercalate periods of hypoxia (4 days)—normoxia (4 days) in a hypobaric chamber during 32 days. At the end of the exposure, hearts were mounted in a Langendorff system and subjected to 30 min of ischemia followed by 120 min of reperfusion. In addition, we determined HIF-1α and ATP levels, as well as oxidative stress by malondialdehyde and nitrotyrosine quantification. Further, the expression of the antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase was determined. NF-kappaB and myeloperoxidase levels were assessed in the hearts. Relative to N hearts, IH improved left ventricular function (Left ventricular developed pressure: N; 21.8 ± 3.4 vs. IH; 42.8 ± 7.1 mmHg; p < 0.05); reduced oxidative stress (Malondialdehyde: N; 14.4 ± 1.8 vs. IH; 7.3 ± 2.1 μmol/mg prot.; p < 0.05); and increased antioxidant enzymes expression. Supplementation with Ω3 induces similar responses as IH group. Our findings suggest that both, IH and Ω3 in an independent manner, induce functional improvement by antioxidant and anti-inflammatory mechanisms, establishing cardio-protection.  相似文献   
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