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以平邑甜茶继代组培苗为试材,研究了NAA、IBA、ZT和6-BA作用下组培苗的生长、内源多胺(PAs)和一氧化氮(NO)含量的变化。结果表明,在MS培养基中添加0.02 ~ 1.00 mg·L-1的NAA或IBA后,外植体鲜样质量增加率和蛋白质含量以及多胺含量和一氧化氮含量均明显增加,其中浓度在0.10 ~ 0.50 mg·L-1 时增加最高;同样浓度下,NAA处理的外植体鲜样质量增加率和腐胺含量高于IBA。在0.08 ~ 4.00 mg·L-1范围内,随着ZT或6-BA浓度的升高,外植体鲜样质量增加率、可溶性蛋白含量、多胺含量和一氧化氮含量均逐渐升高;同样浓度下,6-BA处理的外植体鲜样质量增率和腐胺含量高于ZT。生长素和细胞分裂素促进组培苗生长与促进内源PAs和NO的生成相伴随,组培苗生长动态与内源多胺和一氧化氮含量的变化趋势一致。 相似文献
994.
LIANG Jun-qing SUN Shi-ran WU Yi-ling GAO Wei-juan XU Hai-bo ZHANG Qiu-yan WANG Hai-rong WEI Cong CHEN Jian-xin CHEN Jing 《园艺学报》2009,25(6):1064-1069
AIM: To investigate the mechanisms and relationship among endothelial dysfunction, renin-angiotensin-aldosterone system (RAAS) and family of interleukins under the condition of excessive fatigue, by using the rats with fatigue stress. METHODS: Healthy male Wistar rats were randomly divided into control group, homocysteine (HCY) group, fatigue stress group, renshen group, shuangshen group and tongxinluo group. Radioimmunoassay was carried out to detect plasma renin activity (PRA), angiotensin II (AngⅡ), aldosterone (ALD), endothelin (ET), thromboxane-2 (TXA2), prostaglandin I2 (PGI2) in plasma and interleukin-1β, 2, 6, 10 (IL -1β, IL -2, IL -6) in sera. ELISA was used to detect NE and IL -10. The content of nitric oxide (NO) in sera was also detected. The bioinformatical analysis was used to determine the relationship between RAAS and endothelial dysfunction. RESULTS: Compared with control group, the levels of ET-1 and TXA2 in fatigue stress group were significantly increased (P<0.01, P<0.05), but the content of PGI2 and NO was significantly decreased (P<0.01, P<0.01). Compared with control group, the renin activity in plasma of animals in fatigue stress group was significantly decreased (P<0.01), the AngⅡ, IL -1β, IL -6 level was significantly increased compared with the control group (P<0.01, P<0.01), and was significantly increased compared with the HCY group (P<0.05, P<0.01, P<0.01). The NE level showed the tendency of decrease in different degree. After the intervention of three kinds of herbs to dredge collaterals, the ET-1, AngⅡ, IL -1β, IL-6 level in plasma was decreased in different degree (P<0.05, P<0.01, P<0.01), and at the same time, the contents of NO and NE level were significantly increased (P<0.05). The ALD level in tongxinluo groups was apparently higher than that in control group and the fatigue stress group (P<0.05). The bioinformatics analysis showed that Ang II and ET, IL-1; PGI2 and ALD; NO and ALD composed of three subsystems and interrelated according to the principle of optimality of complex system, and gradual change regulation was also observed in fatigue stress group. However, in control group, HCY group and tongxinluo group, the same interrelation among subsystems was not existed. CONCLUSION: In a state of long-term excessive fatigue, vascular endothelial dysfunction may be induced, and is related with renin-angiotensin-aldosterone system imbalance and serious turbulence of the autonomic dysfunction. Herbs to dredge collaterals could improve it significantly. The results suggest that bearing excessive fatigue and pressure in long-term may be the potential risk factors to induce vascular endothelial dysfunction and further result in cardio-cerebro vascular diseases, Tongluo therapy may be one of the useful ways to prevent such diseases. 相似文献
995.
Sporamin is a soluble protein in sweet potato, and falls into two distinct homology groups, subfamilies A and B. In this research, a sporamin B was purified and its amino acid sequences, trypsin inhibitor activity (Ti activity) were analyzed. This sporamin B was isolated from sweet potato tubers [Ipomoea batatas (L.) Lam cv. 55-2] through extraction of the water-soluble fraction, dialysis, ultrafiltration and ion-exchange chromatography. Homology determined by polyacrylamide gel electrophoresis showed that mainly one bond appeared in gel after being reduced by SDS (sodium dodecyl sulfate), or by SDS and 2-mercaptoethanol, or in native situation. By comparing the data of the polypeptide mass Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry with those of the mass of the theoretical amino acid sequences from NCBI protein database, it was revealed that it was Q40091|Q40091_IPOBA, sweet potato sporamin B - Ipomoea Batatas (sweet potato) (Batate). The sequence coverage was 70.6%. N-terminal sequence was SETPV (Ser-Glu-Thr-Pro-Val). There is a linear relationship between trypsin inhibitor activity (Ti activity) and amounts of this sporamin B (3-18 μg mL-1). The equation of linear regression was y = 2.5809x + 17.049 (r2 = 0.9966). There was a curvilinear relationship between Ti activity and amounts of this sporamin B (21-150 μg mL-1). The equation of curvilinear regression is y = 14.417ln(x) + 23.26 (r2 = 0.9924). The concentration of sporamin B with Ti activity after heating at 40°C may induce part denature of this sporamin B, and there was no statistic difference after heating at 40, 50, 60°C for 20 min. Heat treatment at more than 90°C leads to a dramatic decrease of trypsin inhibitor efficiency. The results suggested that Q40091|Q40091_IPOBA was the major sporamin B in sweet potato tubers [Ipomoea Batatas (L.) Lam cv. 55-2], which had strong Ti activity, and was stable to both thermal and DTT (DL-dithiothreitol) relatively. 相似文献
996.
阐述了蓝沙还原卡v9.2在保护电子阅览室计算机系统方面上的优势、工作原理、以及使用中常遇到的问题和解决方法。 相似文献
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999.
2BFJ-6型变量施肥精密播种机的研制 总被引:2,自引:0,他引:2
变量施肥精密播种机是精准农业实施的一个重要机械设备.本文针对吉林省中部地区的玉米种植模式,设计了2BFJ-6型变量施肥播种精密播种机.该机一次可完成开沟、变量施肥、精量播种、覆土、镇压等作业.该机变量施肥装置采用GPS实时定位,根据各个地块的测土配方施肥结果,由田间计算机控制液压马达的转速实现实时变量施肥.该机采用勺式精密排种器和单体仿形机构确保了播量的精确和稳定的耕深.实验证实可有效保证变量施肥系统的稳定性和快速响应性及精密播种准确性. 相似文献
1000.
孙兰荣 《农业图书情报学刊》2009,21(10):159-160
着重介绍了香港中央图书馆以人为本的建筑思想、服务理念及为读者提供全方位服务的做法。 相似文献