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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.
883.
黄秋葵种子萌发生理特性分析 总被引:7,自引:0,他引:7
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.
885.
Antioxidant Protection of Edible Oils 总被引:4,自引:0,他引:4
Cheung SC Szeto YT Benzie IF 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(1):39-42
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.
Cui T Li JZ Kayahara H Ma L Wu LX Nakamura K 《Journal of agricultural and food chemistry》2006,54(13):4574-4581
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.
A recombinant pseudorabies virus encoding the HA gene from H3N2 subtype swine influenza virus protects mice from virulent challenge 总被引:7,自引:0,他引:7
Tian ZJ Zhou GH Zheng BL Qiu HJ Ni JQ Yang HL Yin XN Hu SP Tong GZ 《Veterinary immunology and immunopathology》2006,111(3-4):211-218
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.
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