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排序方式: 共有224条查询结果,搜索用时 15 毫秒
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Masafumi Toyoshima Yoshinori Tanaka Mitsuyo Matumoto Miyuki Yamazaki Satoru Nagase Kazuo Sugamura Nobuo Yaegashi 《Luminescence》2009,24(5):324-331
In order to facilitate the discovery and investigation of anti‐cancer therapeutics under physiological conditions, we have engineered the ovarian cancer cell line, HM‐1/luc, in mice. This cell stably expresses firefly luciferase and produces light that can be detected using an in vivo imaging system (IVIS). Parental HM‐1 cells cause severe carcinomatous peritonitis to B6C3F1 mice, but not to C57BL6 mice. Established HM‐1/luc cells showed pathologically similar findings to HM‐1 cells. HM‐1/luc cells were injected into the peritoneal cavity of B6C3F1 mice and IVIS 2000 was conducted weekly after inoculation to monitor intra‐peritoneal tumor growth. The mice were divided into three groups: non‐CDDP‐treated (control) and CDDP‐treated (0.2 and 0.4 mg). A disease‐suppressive effect of the CDDP was reflected by the significantly prolonged survival of the CDDP‐treated mice (control 23 ± 1.9 days, CDDP 0.2 mg 29.6 ± 2.9 days; p < 0.05); the total photon and area of flux were decreased. The optical imaging of intraperitoneal tumors via in vivo bioluminescence is effective for noninvasive monitoring and semi‐quantitative analysis. Our syngeneic mouse model has the relevant clinical features of ovarian cancer, which makes it a useful model for developing new ovarian cancer therapies. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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The PAM-2000 portable chlorophyll fluorometer represents one of the first commercially available instruments utilizing the Pulse Amplitude Modulation (PAM) measurement principle, and has become a widely used platform for measuring chlorophyll fluorescence in a wide range of study systems. In this paper, we describe a new method for externally driving and gathering data from the PAM-2000, a method that allows the user to execute a pre-defined user run (or runs) and capture (1) rapid induction kinetics (at 2 ms frequency) during all saturating pulses, (2) measures of F, Fo, Fo′, Fm, and Fm′ associated with those same pulses, and (3) changes in fluorescence F at user-defined intervals between pulses, for the entire user run, with all data compressed into a single, manageable data logger file. Practically, the method makes possible, for example, a post-hoc evaluation of the appropriateness of saturation pulse lengths and intensities during a user run. More importantly it captures, during entire user runs, the varied information contained in slow changes in fluorescence between saturating pulses, as well as rapid induction kinetics, quenching coefficients and quantum yields all gathered simultaneously from all saturating flashes.Electronic Supplementary Material Supplementary material is available for this article at 相似文献
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Ewa Lesko Katarzyna Miekus Agnieszka Grabowska Aleksandra Gładys Marcin Majka 《Central European Journal of Biology》2008,3(4):371-379
Silencing of a target-genes by small interfering RNA (siRNA) has emerged as a powerful new tool not only for basic research
but also with potential therapeutic benefits. This paper demonstrates that optimal delivery strategy is crucial for effective
target-gene silencing. Using lipofection, under defined conditions, we were able to markedly down-regulate expression of the
selected genes involved in rhabdomyosarcoma metastasis: MET, CXCR4, LIFR and PAX3-FKHR. 相似文献
66.
An island view of endemic rarity—Environmental drivers and consequences for nature conservation
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Invasion by alien species is nowadays considered as one of the major threats to biodiversity. Thus, the identification of the areas exposed to a greater risk of invasion represents a priority for management purpose, especially in presence of habitats worthy of conservation. This paper aims to propose a method to produce a map of risk of invasion, merging together the threat of invasion by invasive plants and the distribution of habitats with high conservation value, on the case study of the Island of Elba (Tuscan Archipelago). We modelled the potential distribution of six particularly harmful invasive plants and merged these distributions into a map of threat of invasion. This map was overlapped to the map of density of Natura2000 habitats, finally obtaining a map of risk of invasion. According to our analyses, the potential distribution of the invasive species resulted highly influenced by human-related factors. The habitats more at risk are those closer to streets and anthropic habitats, which are more likely to be colonized by the invasive species we studied. We identified some rare habitats which are strongly endangered, highlighting that around 20% of the surface of the Island is exposed to some level of risk of invasion. 相似文献
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Abstract. Many grasslands and arable fields have been abandoned in Europe in the last decades. So far, however, ecologists have not been able to establish one general, unifying theory for successionally induced changes in species composition following abandonment. In fact, the course of succession seems to be unique for each site and year. Here we focused on the analysis of plant functional traits in order to detect general trends in trait responses to succession which would prove independent of site characteristics. We studied permanent plot series of 14 grassland sites in SW Germany that had been abandoned for 25 yr. Species composition as well as the course of succession varied significantly among the grasslands. Response to succession was analysed for the following traits: ‘plant height’, ‘canopy structure’, ‘specific leaf area’ (SLA), ‘storage organ’, ‘vegetative spread’, ‘plant persistence’, ‘seed bank longevity’, ‘start of flowering’, ‘duration of flowering’ and ‘seed mass’. We compared a univariate with a multivariate approach. In the univariate approach, attributes of each trait were analysed separately employing GLM whereas in the multivariate approach all traits were handled together in NMS. Both analyses indicated similar trait responses to succession. There was a significant increase in the proportion of species characterized by the following attributes: plant height > 0.6 m, leaves distributed regularly along the stem, vegetative spread > 100 mm, start of flowering later than May, duration of flowering 1–2 months and seeds of either low or high mass. 相似文献
69.
Vegetation structure characteristics and relationships of Kalahari woodlands and savannas 总被引:1,自引:0,他引:1
J.L. Privette Y. Tian† G. Roberts‡ R.J. Scholes§ Y. Wang† K.K. Caylor¶ P. Frost M. Mukelabai 《Global Change Biology》2004,10(3):281-291
The Kalahari Transect is one of several International Geosphere–Biosphere Programme (IGBP) transects designed to address global change questions at the regional scale, in particular by exploiting natural parameter gradients ( Koch et al., 1995 ). In March 2000, we collected near‐synoptic vegetation structural data at five sites spanning the Kalahari's large precipitation gradient (about 300–1000 mm yr?1) from southern Botswana (~24°S) to Zambia (~15°S). All sites were within the expansive Kalahari sandsheet. Common parameters, including plant area index (PAI), leaf area index (LAI) and canopy cover (CC), were measured or derived using several indirect instruments and at multiple spatial scales. Results show that CC and PAI increase with increasing mean annual precipitation. Canopy clumping, defined by the deviation of the gap size distribution from that of randomly distributed foliage, was fairly constant along the gradient. We provide empirical relationships relating these parameters to each other and to precipitation. These results, combined with those in companion Kalahari Transect studies, provide a unique and coherent test bed for ecological modeling. The data may be used to parameterize process models, as well as test internally predicted parameters and their variability in response to well‐characterized climatological differences. 相似文献
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