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91.
92.
Ishwar Singh Upendra Kumar S. K. Singh Charu Gupta Madhulika Singh S. R. Kushwaha 《Physiology and Molecular Biology of Plants》2012,18(3):229-236
Germination and early seedling growth are important for establishment of maize because maize is chilling sensitive crop and low temperature during early period of growth can be detrimental to subsequent crop growth and productivity. Therefore, it is important to protect maize seedling from cold stress. A study was conducted on induced cold tolerance by 24-epibrassinoslide (EBR) at the Indian Agricultural Research Institute, New Delhi, India. Maize seedlings were raised in green house condition (25/18 °C day-night temperatures). Ten days old seedlings were treated with EBR (0.0, 0.01, 0.1, 1.0 and 10 μM) and then divided into two sets, one set was kept in greenhouse (25/18 °C day-night temperatures) and another was transferred to net house (cold stress). Data on various morpho-physiological traits was recorded after 7, 14 and 21 days of treatment. Exogenous application of 1.0 μM EBR had significant effect on growth and morpho-physiological traits under both conditions. The maize seedlings treated with EBR were more tolerant to cold stress than the untreated one. Significant increase in plant height, dry matter accumulation, chlorophyll content, total soluble proteins and starch contents was observed under both conditions, however, the results were more pronounced under cold stress. 1.0 μ M concentration being the most effective under both conditions. Maintenance of high tissue water content, reduced membrane injury index, increased total chlorophyll, soluble sugar and protein content were taken as the possible indicators of EBR induced chilling tolerance. 相似文献
93.
目的 探讨半夏总生物碱(total alkaloids from Pinellia Ternate,TAPT)对帕金森病模型大鼠的防治作用及其抗氧化机制.方法 采用脑内定位注射6-羟基多巴胺(6-OHDA)建立帕金森病大鼠模型,在模型建立成功的同时给予半夏总生物碱预防性治疗.采用Morris水迷宫进行帕金森病大鼠的行为学检测,用化学比色法检测大脑皮质及血清超氧化物歧化酶(SOD)活力、丙二醛(MDA)、过氧化氢(H2O2)和还原型谷胱甘肽(GSH)的含量.结果 与正常组比较,帕金森病模型组大鼠的逃避潜伏期明显延长(P<0.01),跨越平台次数明显减少(P<0.01);经半夏总生物碱治疗组,大鼠逃避潜伏期明显缩短(P<0.05,P<0.01),跨越平台次数明显增加(P<0.01).帕金森病模型组大鼠脑皮质及血清中MDA、H2O2的含量增加,SOD活性及GSH的含量降低(P<0.01);经半夏总生物碱治疗组,脑皮质MDA、H2O2的含量显著减少(P<0.01),皮质GSH、SOD含量显著增加(P<0.01);半夏总生物碱给药组中低浓度组、中浓度组血清MDA的含量无统计学意义(P>0.05),高浓度组血清MDA含量下降(P<0.01),各治疗组中血清H2O2含量明显下降(P<0.01),血清GSH含量显著增加(P<0.01).结论 半夏总生物碱具有改善学习记忆能力,对抗大鼠神经系统的退行性变有一定的作用,可能通过改变帕金森病模型大鼠皮质部分及血清SOD、GSH的含量,而抑制了MDA和H2O2的产生. 相似文献
94.
孙家志 《微生物学免疫学进展》2012,40(2):34-35
目的了解全自动血型鉴定系统用于检测ABO血型和Rh(D)血型的效果。方法采用深圳爱康AK03A型数字血型仪对北海市中心血站2010年5月—2011年12月无偿献血者20702份样本进行ABO血型和Rh(D)血型鉴定,并与手工试管法进行对比验证。结果发现正反定型不一致的有75例,ABO初筛血型错误的36例,Rh(D)阴性的53例。结论全自动血型鉴定系统检测血型快捷、方便、高效,能降低检测人员的工作强度,但判读结果时需要与手工试管法结合进行验证,才能得出正确的结果。 相似文献
95.
目的:评价外囊完整剥除术治疗肝包虫病的临床疗效。方法:将226例接受手术治疗的肝脏囊性包虫病患者分为两组:143例行内囊摘除术,83例行外囊完整剥除术,比较两组临床疗效及预后。结果:全囊摘除组的术后住院时间、带管时间、术后并发症及复发率均明显少于内囊摘除组(P均<0.05)。结论:外囊完整剥除术是一种安全、方便、损伤小的根治性术式,有利于降低包虫复发和胆瘘等并发症,关键在选择适应征及正确认知和处理包虫外囊周围管道。 相似文献
96.
冯婉娟刘贝孟令锋张立张蓉颖 《现代生物医学进展》2012,12(10):1862-1864
目的:研究秀丽隐杆线虫(简称线虫)中一种扩展的Synaptotagmin同源物ESYT-2在致密核心囊泡分泌过程中起到的作用。方法:以线虫为研究对象,运用线虫腔胞吸收ANF-GFP的基本原理来确定ESYT-2与分泌相关,之后又进一步使用全内反射荧光显微镜技术(TIRFM)来研究ESYT-2对致密核心囊泡的具体调控。结果:①ESYT-2功能缺失影响线虫神经细胞致密核心囊泡分泌。②ESYT-2影响致密核心囊泡分泌的栓系过程。结论:ESYT-2调控了致密核心囊泡的分泌过程。 相似文献
97.
Normalisation of data to minimise the impact of technical variation on comparative sample analysis is often carried out. Using SELDI data as a model, we have examined the effects of normalisation by TIC which is commonly used for MS data. Significant intergroup differences in normalisation factor were found for serum profiles which could not be explained by experimental factors, implying that normalisation by TIC may in some situations also normalise biological differences and should be systematically evaluated. 相似文献
98.
Determination of fungal activity in modified wood by means of micro-calorimetry and determination of total esterase activity 总被引:1,自引:0,他引:1
Beech and pine wood blocks were treated with 1,3-dimethylol-4,5-dihydroxyethylen urea (DMDHEU) to increasing weight percent gains (WPG). The resistance of the treated specimens against Trametes versicolor and Coniophora puteana, determined as mass loss, increased with increasing WPG of DMDHEU. Metabolic activity of the fungi in the wood blocks was assessed as total esterase activity (TEA) based on the hydrolysis of fluorescein diacetate and as heat or energy production determined by isothermal micro-calorimetry. Both methods revealed that the fungal activity was related with the WPG and the mass loss caused by the fungi. Still, fungal activity was detected even in wood blocks of the highest WPG and showed that the treatment was not toxic to the fungi. Energy production showed a higher consistency with the mass loss after decay than TEA; higher mass loss was more stringently reflected by higher heat production rate. Heat production did not proceed linearly, possibly due to the inhibition of fungal activity by an excess of carbon dioxide. 相似文献
99.
Constitutive plasma membrane targeting and microdomain localization of Dok5 studied by single-molecule microscopy 总被引:1,自引:0,他引:1
In the present study, single-molecule fluorescence microscopy was used to examine the characteristics of plasma membrane targeting and microdomain localization of enhanced yellow fluorescent protein (eYFP)-tagged wild-type Dok5 and its variants in living Chinese hamster ovary (CHO) cells. We found that Dok5 can target constitutively to the plasma membrane, and the PH domain is essential for this process. Furthermore, single-molecule trajectories analysis revealed that Dok5 can constitutively partition into microdomain on the plasma membrane. Finally, the potential mechanism of microdomain localization of Dok5 was discussed. This study provided insights into the characteristics of plasma membrane targeting and microdomain localization of Dok5 in living CHO cells. 相似文献
100.
Nitrogen loss in chicken litter compost as affected by carbon to nitrogen ratio and turning frequency 总被引:7,自引:0,他引:7
The study was undertaken to investigate the effects of carbon to nitrogen (C:N) ratio and turning frequency (TF) on the loss of total nitrogen (TN) during composting of chicken litter (a mixture of chicken manure, waste feed, feathers and sawdust) with a view to producing good quality compost. Carbon to nitrogen ratios of 20:1, 25:1 and 30:1 and TF of 2, 4 and 6 days were experimented. The initial physico-chemical properties of the litter were determined. During the composting process, moisture level in the piles was periodically replenished to 55% and the temperature, pH and TN of the chicken litter were periodically monitored. Also, the dry matter (DM), total carbon (TC), total phosphorus (P) and total potassium (K) were examined at the end of composting. The results showed that both C:N ratio and TF had significant (p < or = 0.05) effect on pile temperature, pH changes, TN, TC, P and K losses while DM was only affected (p < or = 0.05) by C:N ratio. All treatments reached maturation at about 87 days as indicated by the decline of pile temperatures to near ambient temperature. Losses of TN, which were largely attributed to volatilization of ammonia (NH3), were highest within the first 28 days when the pile temperatures and pH values were above 33 degrees C and 7.7, respectively. Moisture loss increased as C:N ratio and TF increased. In conclusion, the treatment with a combination of 4 days TF and C:N ratio 25:1 (T4R25) had the minimum TN loss (70.73% of the initial TN) and this indicated the most efficient combination. 相似文献