中药沙棘提取液对血液肿瘤细胞杀伤作用研究

探讨中药沙棘提取液对人慢性髓样性白血病细胞（K562）、人急性粒细胞白血病细胞（HL-60）、小鼠T淋巴瘤细胞（YAC-1）肿瘤细胞的杀伤作用及其作用机理。方法利用不同浓度沙棘提取液与K562、HL-60、YAC-1肿瘤细胞体外培养24h,测定肿瘤细胞DNA合成能力及脱氧尿嘧啶核酸（UdR）释放率。结果受视药对HL-60、YAC-1细胞DNA合成有抑制作用,对K562细胞DNA中UdR有释放作用。结论沙棘提取液对血液肿瘤细胞生长有明显抑制作用,其药物机理可能与沙棘对其DNA合成的解聚作用和抑制合成作用有关。     

阿魏酸钠对人大肠癌Moser细胞和乳腺癌MCT7细胞增殖和凋亡的影响

目的:研究大肠癌 Moser 细胞和乳腺癌 MCF7细胞对市售4种中药制剂(斑蟊酸钠、苦参素、华蟾素和阿魏酸钠)的敏感性,以及阿魏酸钠影响大肠癌细胞增殖的可能机理。方法:采用 MTT 法测定药物对细胞增殖的抑制率和药物间的协同抑制作用;酶联免疫法检测 CEA 表达水平;流式细胞法测定细胞周期。结果:4种中药对乳腺癌 MCF7细胞的增殖均有不同程度的抑制作用,但只有阿魏酸钠可明显抑制大肠癌Moser 细胞的增殖;阿魏酸钠与5种化疗药物联合对 Moser 细胞有协同作用;阿魏酸钠对 Moser 细胞表达CEA 没有影响;阿魏酸钠可诱导 Moser 细胞凋亡。结论:斑蟊酸钠、苦参素和华蟾素对不同肿瘤细胞的抑制效果差异很大;阿魏酸钠不仅有抑制肿瘤细胞增殖的作用,还与化疗药物有协同效果;阿魏酸钠抑制 Moser 细胞增殖的机理似与转化生长因子信号传导途径无关。     

核桃楸皮提取物对人肝癌细胞SMMC-7721的增殖抑制作用及对细胞周期的影响（英文）

研究核桃楸皮提取物(EMBJM)对人肝癌细胞SMMC-7721的增殖抑制作用及对细胞周期的影响。体外培养SMMC-7721细胞,并用不同浓度核桃楸皮甲醇提取物处理。通过MTT法研究EMBJM对SMMC-7721细胞增殖活性的影响;采用流式细胞仪分析EMBJM对SMMC-7721细胞周期的影响。EMBJM可以显著抑制SMMC-7721细胞生长,具有时间和计量依赖性。细胞周期实验表明EMBJM将SMMC-7721细胞阻滞在G2/M和S期,并具有剂量依赖性。EMBJM质量浓度为8和16mg/L时,G2/M期细胞所占百分比分别为13.89%±2.46%和14.35%±2.68%,与空白对照组(8.34%±1.42%)比较,差异均有统计学意义(P0.05);同等浓度范围内S期细胞所占百分比分别为39.87%±2.83%和44.81%±2.93%,与空白对照组(26.80%±1.76%)比较,差异均有统计学意义(P0.05)。桃楸皮甲醇提取物可以影响SMMC-7721细胞周期分布和有效抑制SMMC-7721细胞生长。     

格氏栲天然林凋落物对马尾松种子萌发的影响

目的 了解格氏栲天然林凋落物对主要伴生种马尾松种子萌发与胚根生长的影响。 方法 通过探究天然林凋落物不同分解层及浓度浸提液对马尾松种子萌发和胚根生长的化感效应。 结果 表明：（1）影响马尾松种子萌发的主要因素是凋落物分解层,未、全分解层凋落物对马尾松种子萌发无显著作用;半分解层抑制发芽率和发芽指数,促进发芽势。（2）影响胚根生长的主要因素是浸提液浓度和作用时间,并受分解层-浓度-时间综合作用,未分解层对马尾松种子整个胚根生长期除1∶5浓度呈抑制作用外,随浓度降低促进作用增强,1∶ 100浓度时促进作用最强;半分解层呈低浓度和高浓度促进,中间浓度抑制;全分解层总体呈促进作用,且随浓度降低促进作用减弱。（3）对应分析表明不同分解层-浓度对马尾松种子萌发无显著相关性,对胚根生长有显著相关性。 结论 不同分解层凋落物浸提液对马尾松种子萌发作用较弱,对胚根生长在低浓度下呈促进作用,高浓度未分解层浸提液有抑制作用,而半分解和全分解浸提液具有促进作用,凋落物化感作用更明显作用于胚根生长。     

紫花苜蓿浸提液对美丽胡枝子等3种灌木的他感作用研究

作者利用5％,10％,15％,20％不同浓度紫花苜蓿茎叶浸提液检测其对美丽胡枝子、马棘、紫穗槐3种灌木种子的发芽及其幼苗生长的影响,分析了紫花苜蓿对3种受体的他感作用。结果表明：15％、20％紫花苜蓿浸提液对美丽胡枝子种子发芽具有明显的促进作用,对马棘和紫穗槐的种子发芽具有抑制作用;紫花苜蓿浸提液对美丽胡枝子幼苗苗长和鲜重影响不大,对马棘幼苗苗长作用不明显,但使马棘幼苗鲜重降低,对紫穗槐的幼苗生长产生明显抑制作用,使苗长和苗鲜重均降低;紫花苜蓿浸提液对3种灌木幼苗根生长均产生明显的抑制作用,且随浓度的增大,抑制作用增强,并且马棘和紫穗槐的敏感性强于美丽胡枝子。     

含羞草叶子提取物对常见农作物种子萌发生长的抑制作用

观察了含羞草叶子提取物对孟加拉常见农作物种子萌发生长的抑制作用.实验在27-30℃的室温和24小时的光照条件下进行.结果表明：不同浓度的含羞草叶子提取物明显影响所选的植物种子根,茎和侧根的延长和生长.生物学测定表明：高浓度（50%-100%）的提取物有较强的抑制作用.而低浓度 （10%-25%） 的提取物的抑制作用较弱.研究还显示,提取物对植物根和侧根的抑制作用比对种子萌发和茎的生长抑制作用更显著.     

华蟾素诱导白血病细胞凋亡和线粒体跨膜电位下降的实验研究

目的:观察华蟾素对白血病细胞的凋亡诱导作用并探讨其机制。方法:用 MTT 法观察华蟾素对 HL-60细胞的生长抑制作用,通过形态学方法、DNA 电泳、流式细胞仪技术、Annexin V 标记法检测华蟾素作用后 HL-60细胞的凋亡发生情况,通过罗丹明染色检测华蟾素作用后 HL-60细胞线粒体跨膜电位的变化。结果:华蟾素作用后 HL-60细胞线粒体跨膜电位下降并发生调亡,在0.0625～0.5 μg/ml 的浓度范围内具有一定的量效关系。结论:华蟾素对白血病细胞具有凋亡诱导作用,其机制与破坏线粒体的功能有关。     

24种竹笋蛋白对肿瘤细胞增殖的抑制作用

目的:探讨不同种类竹笋蛋白对胃癌细胞SGC7901和结肠癌细胞HCT116增殖活性的影响。方法:采用植物活性蛋白提取试剂盒从24种不同种类竹笋中提取蛋白并进行BCA法定量,CCK-8细胞增殖活性检测方法检测不同竹笋蛋白对胃癌细胞SGC7901和结肠癌细胞HCT116增殖活性的影响;不同浓度竹笋蛋白作用胃癌细胞SGC7901和结肠癌细胞HCT116,72 h后采用显微镜拍照记录细胞生长情况。结果:24种竹笋蛋白均可不同程度地抑制胃癌细胞SGC7901和结肠癌细胞HCT116的增殖,同一种竹笋蛋白不同浓度的增殖抑制率不同,呈现出一定的浓度依赖关系;24种竹笋蛋白作用胃癌细胞SGC7901和结肠癌细胞HCT116,72 h后细胞生长受到明显的抑制。结论:竹笋蛋白对肿瘤细胞,如胃癌细胞SGC7901和结肠癌细胞HCT116均有显著的抑制作用,为肿瘤的发生发展的预防治疗提供了重要方法参考,具有一定的临床开发价值。     

镉胁迫对丝瓜幼苗生长的影响

以丝瓜为材料,通过水培试验,研究了镉（Cd2＋）处理对丝瓜幼苗生长的影响。结果表明,Cd2＋溶液浓度等于5mg/L,可增加株高、主根长、侧根数量和幼苗干重,有利于幼苗生长;Cd2＋溶液浓度5～100mg/L对其幼苗生长势和生长量有抑制作用,侧根数少且短小,且随浓度增大抑制作用逐渐增强。100mg/L Cd2＋处理对株高的长度和茎叶重的有抑制作用,而对主根的长度和根系的抑制作用更大。结论是低浓度（≤5mg/L）的Cd2＋处理对丝瓜生长有促进作用,最适于丝瓜生长的Cd2＋浓度为5mg/L;Cd2＋浓度过高（〉5mg/L）则会产生生理毒害作用,进而影响丝瓜幼苗的正常生长。     

紫茎泽兰植株不同部位及浓度的水提液对蓝桉种子萌发和幼苗生长的化感效应

为探讨紫茎泽兰不同部位水提液对蓝桉的化感作用,用紫茎泽兰植株的鲜叶、花、枯叶、茎和根的不同浓度水提液对蓝桉种子进行处理.结果表明,花和鲜叶水提液对蓝桉种子的萌发和幼苗生长的抑制作用远大于枯叶、茎和根的水提液.浓度为0.067 g/mL时,对花和鲜叶的水提液来说,几乎是蓝桉种子萌发和幼苗生长的致死浓度,此浓度的枯叶、茎和根水提液对蓝桉种子萌发和幼苗生长有很强的抑制作用,导致发芽量明显下降及幼苗在形态上发生明显变形;浓度为0.020 g/mL时,花和鲜叶水提液对蓝桉种子萌发及幼苗生长仍有很强的抑制作用,表现在发芽量明显下降及幼苗明显变形,而枯叶、茎和根水提液对蓝桉种子萌发和幼苗生长的抑制作用明显下降,甚至有促进作用,幼苗变形已大为减轻.浓度为0.005 g/mL时,不同部位的水提液对蓝桉种子萌发及幼苗生长的抑制作用进一步下降,而促进作用增强,幼苗已能正常生长.     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

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.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

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.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

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.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

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.     

CAD与建筑设计的关系

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。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

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.     

Risk Perception Among Non-industrial Private Forest Owners

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.     

Interactions in decomposition and N mineralization between tropical legume residue components

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.     

Pasture production and tree growth in a young pine plantation fertilized with inorganic fertilizers and milk sewage in northwestern Spain

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.