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91.
Pilopool is composed of high molecular weight water-soluble chitosan, Allium sativum L. extract, mushroom extract, Dioscorea Batatas D., and purple bamboo salt. This study investigated the effect of Pilopool on performance of forced swimming test (FST). First, the immobility time was decreased in Pilopool-fed group in comparison with control group on FST. In blood serum, the contents of creatine kinase and lactic dehydrogenase were decreased and the contents of glucose and total protein were increased. The results predict a potential benefit of Pilopool as an anti-fatigue agent and for improving physical stamina.  相似文献   
92.
The root of ginseng is one of the most popular natural tonics in Oriental countries. Ginseng grown in the wild, deep in the mountains, is known as Sansam (mountain grown ginseng, MGG). MGG belongs to Araliaceae and Panax. In this study, we investigated the effects of MGG on the cytotoxicity, induction of apoptosis and the putative pathways of its actions in human promyelocytic leukemia cells, HL-60. Using apoptosis analysis, we found that MGG is a potent inducer of apoptosis, but it has less effect on human peripheral blood mononuclear cells. Caspase-3 activation and subsequent apoptotic cell death in MGG-treated cells were partially blocked by the caspase-3 inhibitor, Z-DEVD-FMK. MGG also inhibited the caspase-8 activity. To determine whether MGG-induced apoptosis is involved in tumor necrosis factor-alpha (TNF-alpha) secretion, TNF-alpha secretion was quantified by enzyme-linked immunosorbent assay (ELISA) method. Unexpectedly, MGG significantly decreased the TNF-alpha secretion compared to the control. These results suggest that MGG-induced cytotoxicity have little relation with the secretion of TNF-alpha in HL-60 cells. Furthermore, MGG with rIFN-gamma synergistically increased nitric oxide (NO) production in mouse peritoneal macrophages. Taken together, our data indicate that MGG is a potent inducer of apoptosis on HL-60 cells and these abilities could be used clinically for the treatment of cancer.  相似文献   
93.
When a new facility like a grocery store, a school, or a fire station is planned, its location should ideally be determined by the necessities of people who live nearby. Empirically, it has been found that there exists a positive correlation between facility and population densities. In the present work, we investigate the ideal relation between the population and the facility densities within the framework of an economic mechanism governing microdynamics. In previous studies based on the global optimization of facility positions in minimizing the overall travel distance between people and facilities, it was shown that the density of facility D and that of population ρ should follow a simple power law D ∼ ρ2/3. In our empirical analysis, on the other hand, the power-law exponent α in D ∼ ρα is not a fixed value but spreads in a broad range depending on facility types. To explain this discrepancy in α, we propose a model based on economic mechanisms that mimic the competitive balance between the profit of the facilities and the social opportunity cost for populations. Through our simple, microscopically driven model, we show that commercial facilities driven by the profit of the facilities have α = 1, whereas public facilities driven by the social opportunity cost have α = 2/3. We simulate this model to find the optimal positions of facilities on a real U.S. map and show that the results are consistent with the empirical data.  相似文献   
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小红参的化学成分研究   总被引:4,自引:0,他引:4  
小红参的化学成分研究徐晓莹,周金云,方起程(中国医学科学院中国协和医科大学药物研究所,北京100050)小红参(Rubiayunnanensis(Franch)Diels)是茜草科茜草属植物云南茜草的根(1)。民间根据小红参有温经通络、活血祛风、软坚...  相似文献   
97.
海南粗榧新碱衍生物HH07A对体外L1210细胞的杀伤作用   总被引:1,自引:0,他引:1  
体外培养的小鼠L1210细胞被HH07A2μg·ml-1作用24h后,与对照组细胞相比,其细胞数不再增长,有丝分裂数及集落形成率下降,细胞形态及细胞周期动力学均发生一定的变化。且HH07A大剂量短期作用抑制Ll210细胞集落形成的效率高于低剂量持续作用。  相似文献   
98.
高效液相色谱流通池法测定紫草中假紫草素的含量   总被引:6,自引:0,他引:6  
高效液相色谱法测定紫草提取物中的假紫草素时,出现20个峰,需时75min,主峰保留时间55min,常规方法制备工作曲线很费时。本文报道一种新的工作曲线法——流通池法的原理和方法,测定结果与常规方法一致,可以节省时间。  相似文献   
99.
Summary— Compounds able to inhibit phospholipases A2 can be considered as potential anti-inflammatory drugs. In this respect, the inhibitory effect of the phospholipid analogue 1-decyl 2-octyl-rac-glycero-3-phosphocholine (decyloctyl-GPC) added to the culture medium of rat peritoneal macrophages stimulated with ionophore A23187 was determined, (a) The substrate of phospholipase A2 1-octadecanoyl 2-[14C]eicosatetraenoyl-sn-glycero-3-phosphocholine ([14C]20:4-GPC) was added to the culture medium. In macrophages + extracellular fluids, its hydrolysis at the 2-position, produced [14C]non-phosphorous lipids which reached 12% of the dose at 0.14 μM, 73% at 0.9 and > 90% at 1.6 μM; in experiments where macrophages and extracellular fluids were analyzed separately, decyloctyl-GPC initially added at 4 μM, significantly inhibited the release of [14C]fatty acids and the eicosanoid synthesis, demonstrating its ability to inhibit secreted and/or intracellular phospholipases A2. (b) Extracellular fluids were separated from the macrophages and incubated with [14C]20:4-GPC: 48% of the dose was hydrolyzed by extracellular fluid-associated secreted phospholipase A2 and decyloctyl-GPC at 3 μM, reduced this hydrolysis by 50%. (c) [3H]arachidonic acid ([3H]20:4) was added to the culture medium and was esterified in the macrophage membrane phospholipids. Activation of intracellular phospholipase A2 induced the release of [3H] fatty acids and eicosanoid synthesis. These releases were inhibited by 50% with decyloctyl-GPC added at 4 μM. (d) [3H]20:4 and [14C]20:4-GPC were added to the culture medium of the macrophages. [3H] and [14C] fatty acids and eicosanoids were released in macrophages or extracellular fluids. They were significantly reduced by the phospholipid analogue added at 4 μM. It is concluded that secreted and intracellular phospholipases A2 were both inhibited by decyloctyl-GPC which extensively reduced the 20:4 release from exogenous and membrane phospholipids and therefore eicosanoid synthesis.  相似文献   
100.
Endothelial microparticles (EMP) released from activated or apoptotic endothelial cells (EC) are emerging as useful markers for detection of EC dysfunction. Our recent observation that EMP carry von Willebrand factor (vWf) led us to investigate their interaction with platelets. EMP were incubated with normal washed platelets in the presence or absence of ristocetin, then platelet aggregates were measured by flow cytometry. In the absence of ristocetin, negligible EMP conjugated with platelets (< 5%) but in the presence of ristocetin (1 mg mL(-1)), EMP induced up to 95% of platelets to aggregate. EMP-platelet interaction was 80% blocked by anti-CD42b, or by 0.1 microm filtration to remove EMP. Platelet aggregates induced by normal plasma or high molecular weight vWf (Humate-P) dissociated 50% within 15-25 min following 1:20 dilution. In contrast, aggregates formed with EMP persisted two- to threefold longer with the same treatment, indicating greater stability. A similar degree of prolongation of dissociation was observed using plasma from thrombotic thrombocytopenic purpura (TTP) patients compared with normal plasma. Addition of EMP to plasma from severe von Willebrand disease restored his ristocetin-induced platelet aggregation. Multimer analysis of vWf on EMP showed unusually large vWf (ULvWf). In summary, EMP carries ULvWf multimers, promote platelet aggregates, and increase the stability of the aggregates thus formed.  相似文献   
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