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881.
随着全球经济一体化和我国加入“WTO”,民营种业面临着与国有种业集团及公司、跨国种业集团的竞争,市场竞争程度更加激烈。在这种新的竞争格局之中,如何充分发挥民营种业自身优势和潜能,在种子市场竞争中找到自己的位置,成为当今中国民营种业急需解决的重要问题,对民营种业保持可持续发展有着重要的意义和深远的影响。  相似文献   
882.
以3个超级杂交稻组合P88S/0293、Ⅱ优明86、两优培九并结合三系杂交稻汕优63、常规稻湘州8号为对照材料,在抽穗期通过对各材料剑叶维管组织石蜡切片显微结构比较分析,发现超级杂交稻组合中负责光合同化产物运输的维管束数量多,承担有机物运输的韧皮部面积在整个维管束面积中占较大比例,其有利于光合产物的有效运输;供试各超级杂交稻组合植物维管组织结构具有明显的C3植物特征,在同化物运输有关的一些方面具有优势。  相似文献   
883.
黄秋葵种子萌发生理特性分析   总被引:7,自引:0,他引:7  
陈禅友  童莉 《种子》2004,23(11):14-17
本文探讨了黄秋葵种子发芽率和种子活力等指标的形成与应用,并测定了黄秋葵种子萌发期间的吸水量、呼吸速率和过氧化氢酶活性变化及其种子活力.结果表明,黄秋葵种子属快速发芽种子,这可能与其吸水快,代谢启动快以及呼吸、酶活性等生理生化变化等有关.吸水速度很快、量大且持续时间较长,24h后吸水量上升到77.8%,6d后达196%;呼吸速率和过氧化氢酶活性变化曲线均较平稳,24h后呼吸速率上升到较高水平(5.31 μmol·g-1·min-1),随后3d内呼吸速率略有下降,第5天达到小高峰(5.98μmol·g-1·min-1),并维持在较高水平;过氧化氢酶活性也在24h后达到较高水平(31.00mg·g-1·min-1),2~4d内其活性平稳上升,高峰不明显.  相似文献   
884.
为明确膜下滴灌条件下花生高产栽培适宜的施肥方式,以青花7号花生品种为材料,以不灌水不追肥为对照,在花生生育期间施肥总量相同的情况下,设置7个追肥处理,开展两年大田试验,研究了膜下滴灌分次施肥对花生衰老特性和产量的影响.结果表明,不同时期追肥均可不同程度提高花生叶片叶绿素含量、净光合速率和超氧化物歧化酶(SOD)、过氧化...  相似文献   
885.
Antioxidant Protection of Edible Oils   总被引:4,自引:0,他引:4  
The ability of different cooking oils to withstand oxidation was investigated in relation to their native antioxidant capacity [measured as the Ferric Reducing/Antioxidant Power (FRAP) value]. The antiperoxidation effect of the presence of the Chinese herbs, du-zhong (Cortex Eucommia ulmoides) and ginseng (Panax ginseng C.A. Mayer) in corn oil was also investigated over 26 days’ storage at 55°C. Results showed that sesame oil had the highest FRAP value (803 μM), followed by canola oil (400 μM), and sunflower, peanut, corn and olive oils (100–153 μM). Oils with higher intrinsic antioxidant content showed higher resistance to oxidation, although this was not statistically significant. Corn oil to which was added the herbs du-zhong, ginseng or both had increased resistance to oxidation (conjugated diene level and lipid peroxide formation) over 26 days. FRAP values of the oil/herb mixtures decreased during this time, implying utilisation of herbal antioxidants. Results have implications for increasing the shelf-life and usage time of cooking oils by addition of herbs which can increase resistance of the oil to oxidation. Results have implications also for health, as it is possible that ingestion of these herbs could increase resistance of polyunsaturated fatty acids of cell membranes and lipoproteins to oxidation within the body.  相似文献   
886.
The levels of seven polyphenols (epicatechin, procyanidin B2, procyanidin B5, procyanidin C1, hyperoside, isoquercitrin, and chlorogenic acid) and two triterpene acids (oleanolic acid and ursolic acid) in the matured fruits of Chinese hawthorn (Crataegus pinnatifida Bge. var. major N.E.Br.) were determined by high-performance liquid chromatography methods. The average contents of those constituents in 37 representative cultivars were 1405, 1505, 339, 684, 56, 41, 234, 952, and 147 microg/g fresh weight (FW), respectively. A significant inverse correlation between the procyanidin contents and the latitude of the geographical origin of the cultivars was observed (r = 0.3851, P < 0.02). Correlation analysis of the levels of the nine compounds in the 37 cultivars yielded a strong correlation (P < 0.001) between the individual levels of the four procyanidins and the sum of the procyanidins level (r = 0.7413-0.9898) and between the flavonoids and the chlorogenic acid (r = 0.5383-0.9212). The changes in level of the nine compounds in the hawthorn fruit were evaluated during maturation using the Hebei Dajinxing cultivar. Sixty-one days after blossom, the polyphenol level reached the highest point and the sum of the contents was 1.36 g/100 g FW.  相似文献   
887.
The hemagglutinin (HA) gene of A/Swine/Inner Mogolian/547/2001 (H3N2) swine influenza virus (SIV) was recombined into the genome of pseudorabies virus (PRV) Bartha-K61 vaccine strain, generating a recombinant PRV expressing the HA gene, designated as rPRV-HA. One group of 15 mice was inoculated intranasally (i.n.) with 10(5.0) PFU of rPRV-HA, and another two control groups of mice (15 mice per group) were mock-inoculated or inoculated with Bartha-K61. Mice inoculated with rPRV-HA developed hemagglutination inhibition antibodies 3 weeks post-inoculation. Twenty-eight days post-inoculation, all mice were challenged i.n. with 10(5.0) TCID50 of A/Swine/Heilongjiang/74/2000 (H3N2). No challenge virus was isolated from vaccinated mice, and mild pathological lesions were observed only in lungs following challenge. The results demonstrate that the recombinant rPRV-HA expressing the HA gene from H3N2 SIV can protect mice from heterologous virulent challenge, and may represent a candidate vaccine against SIV.  相似文献   
888.
采集具有临床型乳腺炎奶牛的奶样,经细菌的分离培养、纯培养和生化试验,以确定奶牛临床型乳腺炎的致病菌种类。结果发现患临床型乳腺炎奶牛的致病菌和占分离菌株的百分率为:腐生葡萄球菌19.7%、金黄色葡萄球菌16.5%、兽疫链球菌17.3%、停乳链球菌9.4%、乳房链球菌3.9%、无乳链球菌1.6%、产气肠杆菌17.3%、聚团肠杆菌4.7%、奇异变形杆菌3.0%、大肠杆菌3.0%、蜡样芽胞杆菌3.0%,样品中单纯感染与混合感染的百分率分别为66.0%和27.8%。  相似文献   
889.
试验旨在研究葡萄糖氧化酶(GOD)和乳酸菌制剂联合应用对肉鸡肠道形态及微生物菌群的影响.选取1日龄AA肉鸡1200只,随机分为4组,Ⅰ组为对照组,正常饮水;Ⅱ组为GOD组,在饮水中添加0.1% GOD;Ⅲ组为乳酸菌制剂组,在每只鸡饮水中添加1.5×105 CFU/(g·d)乳酸菌制剂;Ⅳ组为GOD与乳酸菌制剂联合应用组...  相似文献   
890.
Occurrence of lethal cardiac arrhythmia, which is associated with prolongation of the QT interval in electrocardiogram(ECG), is related to increased mortality in the patients with diabetes mellitus (DM). Increased QT interval reflects the prolonged cardiac action potential duration (APD). APD abnormality is based on by cardiac ion channel remodeling induced by DM-related pathological changes. As DM is becoming an important risk factor for atrial fibrillation, the most clinically common arrhythmia, this review mainly summarizes the alterations of ion channel currents and relevant protein expression in diabetic ventricular myocytes to explore the underlying mechanisms of arrhythmia, and also discusses some research achievements from investigating the atrial myocytes in DM.  相似文献   
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