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991.
将生态学领域中的Iogistic方程引入微生物动力学的研究中,建立了3个分别基于Monod方程、Herbert方程和Logistic方程的关于培养基中的微生物浓度(χ)和底物浓度(s)的模型以形成对照.同时建立了基于Logistic方程的关于微生物浓度(χ)和时间(t)的模型.这些均采用实验数据拟合以证明其精确性.该工作有助于研究微生物生长特性,同时有助于进一步地研究可生化降解的有机物在水体的微生物作用下的氧化分解过程,建立新的河流、湖泊、水库等生物学水质模型.本研究中采用的数值方法是非线性最小二乘法、Interior-reflective Newton算法.在Lorynebacterium glutamicum分批培养和Pseudomonas sp.分批培养中,基于Logistic方程的χ-s模型拟合的相关系数分别是0.9940和0.9867,在Pseudomonas sp.分批培养中,z-t模型拟合的相关系数是0.9972。 相似文献
992.
银杏为我国传统的名贵树种,其生长缓慢、结实晚,一般要20多a才能开花结实,并且产量低。阐述银杏的生物学特征、繁殖方式、栽培管理方法、修剪整形及病虫害防治等实用技术,旨在为扩大银杏园林生产、提高银杏的种植质量和产量提供有益的参考。 相似文献
993.
以2 a生楸树实生苗为试验材料,研究了腐殖酸液肥、生物菌肥、保水剂和生根粉技术对提高丘陵山区困难立地造林成活率的应用效果.结果表明:在栽植穴内施入腐殖酸液肥、施用抗旱保水剂或使用GGR生根粉溶液对根系进行浸泡处理,均能显著提高楸树在困难立地上的造林成活率;在栽植穴内填加生物菌肥,对造林成活率没有显著影响.试验中,每株施用2.5 kg腐殖酸液肥或施用200 g抗旱保水剂,造林成活率最高;此外,使用1000 mg/L的GGR1号生根粉溶液浸泡苗木根系2 min,造林后成活率最高. 相似文献
994.
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996.
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
997.
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
998.
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
999.
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
1000.