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Berberine induces cell cycle arrest and apoptosis in human gastric carcinoma SNU-5 cell line 被引量:36
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作者 Jing-Pin Lin Jai-Sing Yang +2 位作者 Jau-Hong Lee Wen-Tsong Hsieh Jing-Gung Chung 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第1期21-28,共8页
AIM: To investigate the relationship between the inhibited growth (cytotoxic activity) of berberine and apoptotic pathway with its molecular mechanism of action. METHODS: The in vitro cytotoxic techniques were com... AIM: To investigate the relationship between the inhibited growth (cytotoxic activity) of berberine and apoptotic pathway with its molecular mechanism of action. METHODS: The in vitro cytotoxic techniques were complemented by cell cycle analysis and determination of sub-G1 for apoptosis in human gastric carcinoma SNU-5 cells. Percentage of viable cells, cell cycle, and sub431 group (apoptosis) were examined and determined by the flow cytometric methods. The associated proteins for cell cycle arrest and apoptosis were examined by Western blotting. RESULTS: For SNU-5 cell line, the IC (50) was found to be 48 μmol/L of berberine. In SNU-5 cells treated with 25-200 μmol/L berberine, G2/M cell cycle arrest was observed which was associated with a marked increment of the expression of p53, Wee1 and CDk1 proteins and decreased cyclin B. A concentration-dependent decrease of cells in G0/G1 phase and an increase in G2/M phase were detected. In addition, apoptosis detected as sub-Go cell population in cell cycle measurement was proved in 25-200 μmol/L berberine-treated cells by monitoring the apoptotic pathway. Apoptosis was identified by sub-Go cell population, and upregulation of Bax, downregulation of Bcl-2, release of Ca^2+, decreased the mitochondrial membrane potential and then led to the release of mitochondrial cytochrome C into the cytoplasm and caused the activation of caspase-3, and finally led to the occurrence of apoptosis. CONCLUSION: Berberine induces p53 expression and leads to the decrease of the mitochondrial membrane potential, Cytochrome C release and activation of caspase-3 for the induction of apoptosis. 展开更多
关键词 BERBERINE Cell cycle APOPTOSIS Caspase-3 ROS MMP SNU-5 cells
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小型啮齿动物的繁殖能量代价(英文) 被引量:12
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作者 Speakman John R. 《兽类学报》 CAS CSCD 北大核心 2007年第1期1-13,共13页
繁殖是动物向后代传递和保持遗传信息的方式。因此繁殖的意义是显而易见的,但也需要付出代价。主要代价是能量需求增加。在对小家鼠繁殖能量需求的研究中发现,能量摄入在妊娠期只是稍微增加,而在哺乳期则急剧增加。尽管在妊娠期增加的... 繁殖是动物向后代传递和保持遗传信息的方式。因此繁殖的意义是显而易见的,但也需要付出代价。主要代价是能量需求增加。在对小家鼠繁殖能量需求的研究中发现,能量摄入在妊娠期只是稍微增加,而在哺乳期则急剧增加。尽管在妊娠期增加的幅度很小,但这可能反映了消化道和发育的胎儿之间在动物腹中的空间竞争,从而可能使能量摄入受到限制进而影响到繁殖过程。哺乳期间,能量摄入急剧增加,在哺乳后期达到高峰并趋于稳定。对野生鼠的研究也表明,野生鼠妊娠期和哺乳期的能量摄入模式与小家鼠是基本相同的,这样我们在小家鼠研究工作中的发现就具有更普遍的适应意义。对哺乳后期能量摄入的限制机制研究至少已经进行了15年。能量摄入受消化道消化能力的限制(中心限制假说)或者受乳腺泌乳能力限制(外周限制假说)的假说,都不能合理地解释一些现有的结果。我们提出了一个新的假说,即能量摄入可能受啮齿动物散热能力的限制(热耗散限制假说)。很久以来,一直认为散热能力是对大型哺乳动物哺乳的一个限制因素,但它在小型啮齿动物中的意义尚不清楚。传统观点认为,啮齿动物哺乳期对褐色脂肪组织产热水平的调节是为了重新分配能量以满足哺乳所需;但现在看来,实际上可能是动物为了避免体温过高而降低其基本的产热水平。我们在这个领域已经有了一些进展,但要利用这些知识来理解即使很简单的生活史权衡等问题也还有很多的工作需要做。 展开更多
关键词 能量代价 能量摄入 繁殖 啮齿动物 产热
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Silvicultural alternatives to conventional even-aged forest man-agement-what limits global adoption? 被引量:5
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作者 Klaus J Puettmann Scott McG Wilson +10 位作者 Susan C Baker Pablo J Donoso Lars Dr?ssler Girma Amente Brian D Harvey Thomas Knoke Yuanchang Lu Susanna Nocentini Francis E Putz Toshiya Yoshida Jürgen Bauhus 《Forest Ecosystems》 SCIE CAS CSCD 2015年第2期123-138,共16页
Background: The development of forestry as a scientific and management discipline over the last two centuries has mainly emphasized intensive management operations focused on increased commodity production, mostly wo... Background: The development of forestry as a scientific and management discipline over the last two centuries has mainly emphasized intensive management operations focused on increased commodity production, mostly wood. This conventionar' forest management approach has typically favored production of even-aged, single-species stands. While alternative management regimes have generally received less attention, this has been changing over the last three decades, especially in countries with developed economies. Reasons for this change include a combination of new information and concerns about the ecological consequences of intensive forestry practices and a willingness on the part of many forest owners and society to embrace a wider set of management objectives. Alternative silvicultural approaches are characterized by a set of fundamental principles, including avoidance of clearcutting, an emphasis on structural diversity and small-scale variability, deployment of mixed species with natural regeneration, and avoidance of intensive site-preparation methods. Methods: Our compilation of the authors' experiences and perspectives from various parts of the world aims to initiate a larger discussion concerning the constraints to and the potential of adopting alternative silvicultural practices. Results: The results suggest that a wider adoption of alternative silvicultural practices is currently hindered by a suite of ecological, economic, logistical, informational, cultural, and historical constraints. Individual contexts display their own unique combinations and relative significance of these constraints, and accordingly, targeted efforts, such as regulations and incentives, may help to overcome specific challenges. Conclusions: In a broader context, we propose that less emphases on strict applications of principles and on stand structures might provide additional flexibility and facilitate the adoption of alternative silvicultural regimes in a broader set of circumstances. At the same time, the acceptance of alternative silvicultural systems as the preferred or default mode of management will necessitate and benefit from the continued development of the scientific basis and valuation of a variety of ecosystem goods and services. This publication is aimed to further the discussion in this context. 展开更多
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