周林频谱：口碑胜过广告

说起中医针法微创治疗脊椎病,“黄枢”可谓鼎鼎大名,虽然他只是一家民营医院的院长。一个门头不大的四层小楼,从高官达贵到平民百姓,每天患者络绎不绝。“一招鲜,吃遍天”,靠的就是这套绝活一一不用开刀的微型外科治疗,术后只有一个针眼大小的伤口,而且疗效还很好。     

绿色财富:让世界更美好——黎祖交教授答《绿色中国》杂志记者问

近年来,“绿色财富”一词频频见诸报端,一些专家学者陆续发表相关文章,一些新闻媒体和学术团体还举办过相关论坛和研讨会。这表明,“绿色财富”的研究已经逐步引起社会关注。但是,究竟什么是绿色财富？绿色财富的创造途径有哪些？记者就此专访了本刊名誉社长、国家林业局经济发展研究中心原主任黎祖交教授。     

保护乳房，该做点什么？

相信很多人曾看过电影《雨人》,这是真实故事改编成的电影,真正的“雨人”金是一个机械记忆能力超强的天才。金的总智商约87,然而他的记忆智商竟高达220。这种智能低下却又在某方面拥有惊人天赋的人,被称为“白痴天才”,也就是“孤独症学者”。令人感到好奇的是,“智能低下”与“天赋惊人”看似矛盾异常的两个方面怎么如此真实地同时出现在一个人身上？     

果用杜仲良种‘华仲9号’

‘华仲9号’杜仲为雌株,是采用选择育种的方法经优株选择、无性系造林测定和区域化试验选育而成,具有结果早,种仁亚麻酸含量高,高产稳产,适应性强等特性。适于营建杜仲良种果园,生产杜仲亚麻酸油和杜仲胶。     

Growth response of cottonwood roots to varied NH4:NO3 ratios in enriched patches

Maximization of short-rotation forest plantation yield requires frequent applications of nutrients, especially nitrogen (N). Whole-plant growth is known to be sensitive to the proportion of ammonium to nitrate (NH4:NO3). However, the extent to which N form affects root growth, branching and morphology is poorly understood, and these variables may have substantial impacts on plant nutrient and water acquisition. We used rooted cuttings of cottonwood (Populus deltoides Bartr. ex Marsh.) to investigate the effect of various NH4:NO3 ratios on root growth in N-enriched patches. A sand culture study with split-root systems was carried out in which 1-3% of the total root system of each cutting was supplied with 2 mM N at NH4:NO3 ratios of 0:100, 20:80, 40:60, 60:40, 80:20 and 100:0 (molar basis), with the rest of the plant supplied with 0 mM N, resulting in the whole plant becoming N deficient. During the experiment, whole-plant growth was unaffected by the treatments. Of the NH4:NO3 ratios tested, greatest total root length, specific root length, and root N concentration of roots in enriched patches occurred in the 20:80 NH4:NO3 treatment. The largest response of roots in enriched patches was third- and fourth-order root production. We conclude that N form has a profound effect on root development and morphology in enriched patches.     

Relationship between H_2O_2 accumulation and NO synthesis during osmotic stress: promoted somatic embryogenesis of Fraxinus mandshurica

Osmotic stress promotes somatic embryogenesis of Fraxinus mandshurica,which leads to accumulation of reactive oxygen species (ROS).The single pieces of cotyledons of F.mandshurica were used as explants to induce somatic embryogenesis in osmotic-stress medium.Furthermore,the hydrogen peroxide H_2O_2 content of explanted cells was varied by adding exogenous H_2O_2 or catalase solution to assess the effects of the exogenous H_2O_2on somatic embryogenesis,intracellular H_2O_2accumulation,and the relationship between signaling mediated by ROS or reactive nitrogen species.The results revealed that exogenous H_2O_2(100?300μmol L~(–1)) increased the number of somatic embryos.On 60th day of exogenous H_2O_2(200μmol L~(–1))treatment,the number of somatic embryos of explants treated,which was 136.54%,was higher than the control.Moreover,exogenous H_2O_2 (100μmol L~(–1)) significantly increased the intracellular H_2O_2content and enhanced the activities of superoxidase dismutase and peroxidase.Finally,exogenous H_2O_2(100μmol L~(–1)) activated the intracellular non-enzymatic pathway for nitric oxide (NO) synthesis.The somatic embryogenesis in broadleaf trees increases with the change of endogenic ROS content,and depends on the upregulation of antioxidant enzymes.Both H_2O_2and NO,as signaling molecules,were found to be involved in the process of somatic embryogenesis in broadleaf trees.In the process of exogenous H_2O_2promoting somatic embryogenesis,NO synthesis depended on non-enzymatic reactions.These results provide a scientific basis for resolving the mechanism by which ROS levels are regulated during somatic embryogenesis of broadleaf trees and establish a reasonable and efficient technology system for regulating somatic embryogenesis of trees.     

Vasorelaxant activity of some structurally related triterpenic acids from Phoradendron reichenbachianum (Viscaceae) mainly by NO production: ex vivo and in silico studies

The aim of the current study was to investigate the vasorelaxant activity of five structurally-related triterpenic acids namely ursolic (1), moronic (2), morolic (3), betulinic (4) and 3,4-seco-olean-18-ene-3,28-dioic (5) acids. The vasorelaxant effect of compounds 1-5 were determined on endothelium-denuded and endothelium-intact rat aortic rings pre-contracted with noradrenaline (0.1 μM). All compounds showed significant relaxant effect on endothelium-intact vessels in a concentration-dependent manner (p<0.05). Ursolic, moronic and betulinic acids were the most potent vasorelaxant agents with 11.7, 16.11 and 58.46 μM, respectively. Since vasorelaxation was blocked by L-NAME, while indomethacin did not inhibit the effect, endothelium-derived nitric oxide seems to be involved in triterpenic 2 and 3 mode of action. Compounds 1-5 were docked with a crystal structure of eNOS. Triterpenes 1-5 showed calculated affinity with eNOS in the C1 and C2 binding pockets, near the catalytic site; Ser248 and Asp480 are the residues that make hydrogen bonds with the triterpene compounds.