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81.
中药金银花药用成分的提取及抑菌实验的研究 总被引:28,自引:1,他引:28
为了研究金银花中抗菌消炎成分总黄酮、绿原酸的提取方法及其抑菌效果,本实验中用金银花的提取物对11种菌种进行筛选,并对其中有抑制作用的菌种进行了最小抑菌浓度的实验。结果表明金银花的提取物对金黄色葡萄球菌和大肠杆菌有较强的抑制作用,对金黄色葡萄球菌的MIC为6.25mg/ml,对大肠杆菌的MIC为12.5mg/ml。 相似文献
82.
Changes and availability of P fractions following 65 years of P application to a calcareous soil in a Mediterranean climate 总被引:4,自引:0,他引:4
The fate and availability of P derived from granular fertilisers in an alkaline Calcarosol soil were examined in a 65-year
field trial in a semi-arid environment (annual rainfall 325 mm). Sequential P fractionation was conducted in the soils collected
from the trial plots receiving 0–12 kg P ha−1crop−1, and the rhizosphere soil after growing wheat (Triticum aestivum L. cv. Yitpi) and chickpea (Cicer arietinum L. cv. Genesis 836) for one or two 60-day cycles in the glasshouse. Increasing long-term P application rate over 65 years
significantly increased all inorganic P (Pi) fractions except HCl–Pi. By contrast, P application did not affect or tended
to decrease organic P (Po) fractions. Increasing P application also increased Olsen-P and resin-P but decreased the P buffer
capacity and sorption maxima. Residual P, Pi and Po fractions accounted for an average of 32, 16 and 52% of total P, respectively.
All soil P fractions including residual P in the rhizosphere soil declined following 60-day growth of either wheat or chickpea.
The decreases were greater in soils with a history of high P application than low P. An exception was water-extractable Po,
which increased following plant growth. Changes in various P fractions in the rhizosphere followed the same pattern for both
plant species. Biomass production and P uptake of the plants grown in the glasshouse correlated positively with the residual
P and inorganic fractions (except HCl–Pi) but negatively with Po in the H2O-, NaOH- and H2SO4-fractions of the original soils. The results suggest that the long-term application of fertiliser P to the calcareous sandy
soil built up residual P and non-labile Pi fractions, but these P fractions are potentially available to crops. 相似文献
83.
The minicontainer-method is a new method developed to study biological processes related to soil litter decomposition. An adaptation of the classical Baermann-funnel technique is described which can be used, in association with the minicontainer method, to investigate the role of Nematoda in litter decomposition. The use of the extraction method is illustrated in a study of the effects of different tillage systems on the decomposition of rye straw and on the nematode density in minicontainers with different mesh sizes of 20 µm, 500 µm and 2 mm. Three tilled plots (conventional deep plough, cultivator and two-layer plough) and an untilled control were compared after periods of 4 weeks and 38 weeks. On both sample dates there were significant main effects of treatment and mesh size on the nematode density, and additionally, after 38 weeks significant treatment x soil depth interactions. After 4 weeks, there were significant main effects of treatment and soil depth on the decomposition, but no mesh size effects, whereas after 38 weeks, all experimental factors had a significant effect on the decomposition of the straw. Due to the small volume of litter substrate used in the minicontainer method, the efficiency of nematode extraction is high and the lack of oxygen in the minicontainers presents no serious problem during the extraction process. The method also allows the simultaneous extraction of a large number of samples within a short period of time. Our results indicate that the method is suitable to study the microdistribution of nematode activity within the soil profile and improves the possible applications of the minicontainer-method. 相似文献
84.
考察5种萃取体系(A:正己烷,B:正己烷/乙醇,C:正己烷/异丙醇,D:氯仿/甲醇,E:氯仿/乙醇)对小球藻(Chlorella phyrenoidosa)油脂的提取效果及藻渣成分的影响。实验结果表明:不同的萃取体系下,油脂得率为D(12.27%)、E(8.87%)、C(7.71%)、B(6.80%)、A(3.91%),藻渣蛋白含量为A(52.60%)、E(46.23%)、B(40.19%)、C(39.52%)、D(32.52%),藻渣碳水化合物含量为A(23.28%)、E(16.15%)、B(13.24%)、D(13.50%)、C(9.06%);藻渣色素含量为A(1.75%)、E(1.29%)、B(1.14%)、C(0.96%)、D(0.58%);藻渣灰分含量为D(3.63%)、E(2.94%)、C(2.23%)、B(2.25%)、A(1.48%)。综合考虑微藻生物柴油的生产及藻渣的可利用性,V(氯仿)/V(乙醇)=1是一种油脂萃取效果较好,藻渣营养成分损失较小的小球藻油脂萃取体系。 相似文献
85.
目的 观察菟丝子不同提取工艺对实验犬血流动力学药效学的影响。方法 16只成年杂种犬随机分成四组,给药组剂量为20mg/kg静脉注射。结果 经初步筛选实验结果表明,三个不同提取工艺样品均能增加心肌冠脉血流量,但3个样品对心肌耗氧量具有不同的影响,其中3号制剂心肌耗氧量降低;而1、2号制剂则增加心肌耗氧量。结论 3个样品各有特点,综合效应3号最佳。 相似文献
86.
研究了不同方法对冬虫夏草发酵菌丝体(以枯叶蛾科昆虫马尾松毛虫为基质发酵所得)中多糖提取的影响。结果表明,采用微波辅助水提法所得多糖的产率最高,影响提取的关键因素为液料比、微波提取时间、微波功率;采用Box-Behnken设计及响应面分析法对这3个因素进行优化,并通过回归拟合,建立了预测虫草多糖提取的多项式模型Y=6.87+0.058A+0.085B+0.075C+0.032AB+0.046AC+0.069BC-0.16A2-0.37B2-0.11C2。经响应面最优化分析,获得冬虫夏草发酵菌丝体中多糖的最优提取工艺参数为:液料比(mL/g)6.3:1、微波功率520W、微波提取时间326s,此工艺提取验证后的提取率达到6.76%。 相似文献
87.
用顺序GISH-FISH 技术鉴定小麦-中间偃麦草小片段易位系 总被引:6,自引:1,他引:6
利用顺序基因组-重复序列原位杂交技术对1个来自中3不育系和普通小麦恢75杂种后代稳定株系H96276-2的染色体组成进行了分析。以中间偃麦草(Agropyronintermedium)基因组DNA为探针的荧光原位杂交结果表明,H96276-2的体细胞中有42条染色体,包括20对小麦染色体和1对小麦-中间偃麦草易位染色体,中间偃麦草染色体的易位片段位于1对小麦染色体的端部。进而用重复序列探针pSc119进行第2次荧光原位杂交,证明H96276-2中的中间偃麦草染色体易位片段位于小麦2B染色体的短臂上。 相似文献
88.
偏斜淫羊藿化学成分研究 总被引:1,自引:0,他引:1
采用70%乙醇超声波辅助提取偏斜淫羊藿(Epimedium truncatum H.R.Liang)叶片中的类黄酮化学成分,利用LC-MS联用技术鉴定其化合物组成,利用HPLC方法测定其主要活性成分的含量并与药典规定药材箭叶淫羊藿(Epimedium sagittatum)主要活性成分的含量进行比较。结果从偏斜淫羊藿叶片中鉴定出6个化合物:朝藿定B、朝藿定C、淫羊藿苷、3,5,7-三羟基4’-甲氧基-8-异戊烯基黄酮-3-O-α-L-吡喃鼠李糖基(1→2)-α-L-吡喃鼠李糖苷、槲皮素-3-O-鼠李糖甙、山奈苷。该6个化合物均为首次在该植物中发现。偏斜淫羊藿富含朝藿定C,其含量显著高于箭叶淫羊藿主要活性成分的总含量。结果表明LC-MS可以简单、快速地对淫羊藿化学成分进行定性和定量分析,偏斜淫羊藿富含朝藿定C,具有潜在的药用价值。 相似文献
89.
摘要 目的:探讨龈沟液炎性因子及TSP-1在拔牙正畸患者中的表达情况及发生牙周疾病的影响因素。方法:选取我院2020年8月到2023年8月收治的80例拔牙正畸治疗患者进行回顾性分析,分别取所有患者正畸前、正畸后1个月、3个月及正畸结束时的龈沟液样本检测肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)、血小板反应蛋白-1(TSP-1)表达水平。随后依照患者正畸治疗过程中是否患有牙周疾病将其分为牙周疾病组(n=36)及非牙周疾病组(n=44),对比两组患者正畸前及正畸结束时的TNF-α、IL-1β、IL-6、TSP-1表达水平,对比两组患者一般情况,采用logistics回归模型分析拔牙正畸患者牙周疾病的影响因素。结果:80例拔牙正畸患者中正畸后1个月、3个月 TNF-α、IL-1α、IL-6、TSP-1水平升高,正畸后3个月到正畸结束时TNF-α、IL-1β、IL-6、TSP-1水平趋于平稳,但正畸后1个月、3个月及结束时明显高于正畸前(P<0.05);牙周疾病组与非牙周疾病组患者正畸前、正畸后TNF-α、IL-1β、IL-6、TSP-1表达水平对比差异显著,牙周疾病组明显高于非牙周疾病组(P<0.05);牙周疾病组及非牙周疾病组患者性别、年龄、BMI对比无明显差异(P>0.05),牙周疾病组及非牙周疾病组患者正畸治疗时间、拔牙数量、正畸方式、口腔清洁度对比差异显著(P<0.05);logistic回归分析结果表明:TNF-α、IL-1β、IL-6、TSP-1、正畸方式、口腔清洁度为拔牙正畸患者牙周疾病的独立危险因素(P<0.05)。结论:拔牙正畸患者随着正畸时间延长龈沟液炎性因子及TSP-1水平明显升高,且TNF-α、IL-1β、IL-6、TSP-1、正畸方式、口腔清洁度为拔牙正畸患者牙周疾病的独立危险因素。 相似文献
90.
R.P. Herd L. Ko S.E. Weisbrode D.D. Heath 《International journal for parasitology》1984,14(2):141-149
Herd R. P., Ko L., Weisbrode S. E. and Heath D. D. 1984. Sequential morphologic changes in adult Echinococcus granulosus during complement-mediated lysis in vitro. International Journal for Parasltology14:141–149. Sequential changes (5,10, 20, 30,40, 50 min, 1, 2, 3, 4, 5, 6, 7, 8, h) were observed by light, scanning and transmission electron microscopy after 38-day-old adult Echinococcus granulosus were exposed to 50% guinea pig serum in vitro. Early changes within 3 h included contraction of worms, fusion of microtriehes, vacuolization and vesiculization of the distal cytoplasm, followed by rupture of vesicles leading to erosion and loss of the distal cytoplasm. This was most marked in the terminal proglottid but ultimately there was complete erosion of the distal cytoplasm of all proglottids and the scolex. After 3 h there was loss of definition of organelles, apparent edema of the perinuclear cytoplasm and, in some instances, rupture of the circular muscle layer with extrusion of parenchyma. Adult tape-worms exposed to heat-inactivated complement showed none of these changes. Lysis and death of the parasite was attributed to osmotic changes subsequent to the formation of trans-membrane channels induced by complement-mediated attack of the tegument after activation of the alternate pathway by factors present in the cestode tegument. 相似文献