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1.
银杏叶聚戊烯基磷酸酯体内外抗肿瘤的生物活性研究 总被引：1，自引：0，他引：1
研究了聚戊烯基磷酸酯(PPH)体外对肿瘤细胞和体内抗移植性肿瘤的抑制作用。从银杏叶中分离制备聚戊烯醇混合物(C75~C110),选择POC l3为磷酰化剂和三乙胺为碱性水解剂,经过磷酰化和水解二步反应,合成聚戊烯基磷酸单酯。以氟脲嘧啶(5-Fu)为对照,体外肿瘤细胞株选择SGC-7901人胃癌、LoVo人结肠腺癌和Hela人宫颈癌;体内移植性肿瘤细胞株选择肝癌实体型(Heps)、肉瘤(S180)、艾氏癌实体(EC),用不同剂量的PPH进行抗肿瘤药效实验。结果表明,银杏叶PPH在高浓度下(0.4 g/L)作用72 h,对3种体外细胞株抑瘤率达到60%~80%;对Heps、S180和EC等移植性瘤株抑瘤率达到50%~65%。这说明银杏叶PPH具有明显的抑制肿瘤的生物活性。 相似文献
2.
以银杏叶为原料，采用皂化反应、溶剂冷冻和Ⅱ级分子蒸馏分离聚戊烯醇不皂化物，精制银杏叶聚戊烯醇（GP），纯度87．3％。通过建立人脑瘤SF763、人肺腺瘤A549和艾氏腹水瘤Ec移植小鼠模型，GP口服给药，研究GP对人脑瘤SF763裸鼠和艾氏腹水瘤Ec小鼠的生命延长率，观察GP对人肺腺瘤A549裸鼠的抑瘤率。结果表明：生药剂量320mg／kgGP联合2mg／kg阿霉素（ADM），其生命延长率为88％（P〈0．01），GP能明显延长荷人脑瘤SF763裸鼠生命；GP在大于40mg／kg时对人肺腺瘤A549裸鼠具有明显的抑制作用（P〈0．05），最佳剂量为GP80mg／kg，接种时间11d，抑瘤率为82．2％（P〈0．01）；GP对艾氏腹水瘤EC小鼠的生存期呈现负量效关系，GP最佳剂量范围在5-10mg／kg，最高生命延长率为32．77％（P〈0．05）。 相似文献
3.
《林产化学与工业》2017,(1)
通过探讨银杏叶聚戊烯醇纳米乳液(GBP)的平均粒径对其自身抗菌增效作用的影响,以及考察最小抑菌浓度(MIC)和分级抑菌浓度(FIC);同时研究亚抑菌浓度条件下,聚戊烯醇纳米乳液与抗生素联合作用的时间-杀菌曲线,研究了银杏叶聚戊烯醇纳米乳液与氨苄西林(A)、环丙沙星(C)、硫酸庆大霉素(G)、红霉素(E)和多粘菌素B硫酸盐(P)这5种抗生素的协同抗菌作用。结果显示:聚戊烯醇乳液配伍抗生素的抑菌圈直径随着乳液平均粒径增大而减小,由此推断聚戊烯醇纳米乳液可能具有提高聚戊烯醇自身的增效能力。聚戊烯醇纳米乳液与硫酸庆大霉素混合对金黄色葡萄球菌具有协同抗菌作用(FIC指数为0.5),混合样抑菌圈值为(25.8±0.1)mm,MIC值为33 mg/L。聚戊烯醇与硫酸庆大霉素混合可以有效地提高对金黄色葡萄球菌的抗菌效果并延长抗菌时间。 相似文献
4.
以银杏叶聚戊烯醇为原料,通过酯化反应合成了聚戊烯基季铵盐、聚戊烯基磷酸钠以及聚戊烯基乙酸酯,并对其结构进行了表征。采用滤纸片法测定了银杏叶聚戊烯醇及其衍生物对于金黄色葡萄球菌(S.aureus)和大肠杆菌(E.coli)的抑菌圈直径,以等倍稀释法测定其最小抑菌浓度(MIC)值,并对其进行抗菌谱测试。结果表明,银杏叶聚戊烯醇衍生物对金黄色葡萄球菌和大肠杆菌的MIC值范围0.062 5～1 g/L,低于银杏叶聚戊烯醇的MIC值范围2～4 g/L,4种样品对于金黄色葡萄球菌和大肠杆菌均有较好的抑制作用,银杏叶聚戊烯醇的抑菌活性较其衍生物略低,4种样品对于枯草芽孢菌和沙门氏菌亦有抑制作用,对于啤酒酵母菌和黑曲霉菌无明显抑菌作用。 相似文献
5.
分子短程蒸馏分离银杏叶聚戊烯醇的研究 总被引：8，自引：3，他引：5
以银杏叶为原料,采用皂化反应、溶剂萃取和冷冻制备聚戊烯醇不皂化物,皂化剂为5%NaOH-EtOH,石油醚软膏与皂化剂的比例为1∶5(g∶mL),首次采用分子短程蒸馏分离聚戊烯醇不皂化物,最佳工艺为:Ⅰ级分子蒸馏,工艺参数为冷凝温度2.5℃,循环水温度60℃,物料加热温度60℃,蒸馏温度160℃,进料速率180mL/h,刮膜转速200r/min,蒸馏真空度0.5～1.0Pa;Ⅱ级分子蒸馏,工艺参数为循环水温度80℃,物料加热温度60℃,蒸馏温度280℃,进料速率180mL/h,刮膜转速300r/min,蒸馏真空0.1～0.5Pa。结果表明:溶剂中聚戊烯醇为55.6%,银杏叶聚戊烯醇(GP)回收率为98.5%,馏余物中聚戊烯醇的含量由不皂化物中的46.2%提高到83.7%,而且无溶剂残留,是工业化制备高纯度聚戊烯醇理想的分离方法。 相似文献
6.
以银杏叶为原料,采用皂化反应、溶剂冷冻和Ⅱ级分子蒸馏分离聚戊烯醇不皂化物,精制银杏叶聚戊烯醇(GP),纯度87.3%.通过建立人脑瘤SF763、人肺腺瘤A549和艾氏腹水瘤EC移植小鼠模型,GP口服给药,研究GP对人脑瘤SF763裸鼠和艾氏腹水瘤EC小鼠的生命延长率,观察GP对人肺腺瘤A549裸鼠的抑瘤率.结果表明:生药剂量320 mg/kg GP联合2 mg/kg阿霉素(ADM),其生命延长率为88%(P＜0.01),GP能明显延长荷人脑瘤SF763裸鼠生命;GP在大于40 mg/kg时对人肺腺瘤A549裸鼠具有明显的抑制作用(P＜0.05),最佳剂量为GP80 mg/kg,接种时间11 d,抑瘤率为82.2%(P＜0.01);GP对艾氏腹水瘤EC小鼠的生存期呈现负量效关系,GP最佳剂量范围在5～10 mg/kg,最高生命延长率为32.77%(P＜0.05). 相似文献
7.
银杏叶聚戊烯醇对小鼠免疫功能和诱导肿瘤细胞凋亡的研究 总被引：8，自引：0，他引：8
用不同剂量银杏叶聚戊烯醇(GP)给正常小鼠和荷瘤小鼠灌胃,用碳粒廓清法分析正常小鼠巨噬细胞吞噬功能;采用流式细胞术(FCM)检测S180荷瘤小鼠的凋亡细胞比率(APO)、S期细胞比率(SPF)和增殖指数(PI)的变化,分析T细胞亚群CD4/CD8比值的影响.结果表明,10和20 mg/kg的GP能提高正常小鼠巨噬细胞的吞噬功能, 对碳粒的清除作用高于环磷酰胺(CTX);高剂量组(40 mg/kg)GP与对照组比较,能增加肝癌(Heps)荷瘤小鼠胸腺指数和艾氏腹水癌(EC)荷瘤小鼠脾指数.5 mg/kg GP对S180荷瘤小鼠细胞的APO为6.35, 明显高于阴性对照组及其它给药组,使S180荷瘤小鼠CD4/CD8比值接近正常小鼠. 相似文献
8.
9.
首先对银杏叶聚戊烯醇含量测定的方法及方法学进行了考察,结果表明:采用高效液相色谱,以C18为色谱柱,以异丙醇/甲醇(体积比32∶18)为流动相,在210 nm下测定聚戊烯醇具有较高的精密度(RSD为0.89%)、较好的稳定性(RSD为3.26%),平均加标回收率为97.4%(RSD为1.75%)。然后通过正己烷提取、皂化、乙醇和丙酮脱蜡,以及硅胶柱层析(V(乙醚)∶V(正己烷)=3∶97)获得纯度为98.6%的聚戊烯醇。在此基础上,对高纯度聚戊烯醇末端羟基进行亲水改性,先与邻苯二甲酰亚胺进行光延反应(mitsunobu反应),再与水合肼进行还原反应,合成了氨基聚戊烯醇,并通过红外和核磁共振氢谱对其结构进行了表征,确认了氨基聚戊烯醇的成功合成。 相似文献
10.
聚戊烯基磷酸酯的合成机理与化学特征 总被引：1，自引：0，他引：1
从银杏叶中分离制备聚戊烯醇混合物(C75~C110),纯度为87.2%,选择POC l3为磷酰化剂和三乙胺为碱性水解剂,经过磷酰化和水解二步反应,聚戊烯基氯磷酸酯在三乙胺碱性溶液中转化成聚戊烯基磷酸酯,产品得率在65%以上。聚戊烯醇与POC l3的摩尔比为1∶5~10,反应温度低于10℃;室温水解20 h,反应产物经柱层析纯化和HPLC制备聚戊烯基磷酸酯,由IR、1H NMR、13C NMR和高分辨质谱(HRMS)鉴定其化学结构为聚戊烯基单磷酸酯。 相似文献
11.
《Scandinavian Journal of Forest Research》2012,27(5):427-435
In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads. 相似文献
12.
《Scandinavian Journal of Forest Research》2012,27(3):206-217
The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage. 相似文献
13.
《Scandinavian Journal of Forest Research》2012,27(1):53-61
This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland. 相似文献
14.
《Scandinavian Journal of Forest Research》2012,27(1):15-27
The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions. 相似文献
15.
本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。 相似文献
16.
《Scandinavian Journal of Forest Research》2012,27(2):131-138
The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided. 相似文献
17.
18.
《Scandinavian Journal of Forest Research》2012,27(5):472-479
Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken. 相似文献
19.
Srisuda Thippayarugs Banyong Toomsan Patma Vityakon Viriya Limpinuntana Aran Patanothai Georg Cadisch 《Agroforestry Systems》2008,72(2):137-148
In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic
or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts
(stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea
(Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content
as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest
N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized
to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea,
largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for
N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant
components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N
released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures
were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality
components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in
the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols.
Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest
age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its
components are mixed. 相似文献
20.
A. Rigueiro-Rodríguez M. R. Mosquera-Losada E. Gatica-Trabanini 《Agroforestry Systems》2000,48(3):245-256
The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste
disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization,
(2) milk sewage sludge at 40 kg N ha−1 target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two
pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha−1. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1); (2) Lolium perenne L. var. Tove (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea
(Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m2, with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect
on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage
sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but
affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral
systems.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献