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61.
Systemic Practice and Action Research - 相似文献
62.
Systemic Practice and Action Research - 相似文献
63.
Julie Lecomte Krystel Louis Benoit Detry Silvia Blacher Vincent Lambert Sandrine Bekaert Carine Munaut Jenny Paupert Pierre Blaise Jean-Michel Foidart Jean-Marie Rakic Stephen M. Krane Agn��s Noel 《Cellular and molecular life sciences : CMLS》2011,68(4):677-686
In this study, we evaluate the potential involvement of collagenase-3 (MMP13), a matrix metalloproteinase (MMP) family member, in the exudative form of age-related macular degeneration characterized by a neovascularisation into the choroid. RT-PCR analysis revealed that human neovascular membranes issued from patients with AMD expressed high levels of Mmp13. The contribution of MMP13 in choroidal neovascularization (CNV) formation was explored by using a murine model of laser-induced CNV and applying it to wild-type mice (WT) and Mmp13-deficient mice (Mmp13 ?/? mice). Angiogenic and inflammatory reactions were explored by immunohistochemistry. The implication of bone marrow (BM)-derived cells was determined by BM engraftment into irradiated mice and by injecting mesenchymal stem cells (MSC) isolated from WT BM. The deficiency of Mmp13 impaired CNV formation which was fully restored by WT BM engraftment and partially rescued by several injections of WT MSC. The present study sheds light on a novel function of MMP13 during BM-dependent choroidal vascularization and provides evidence for a role for MSC in the pathogenesis of CNV. 相似文献
64.
The Relationship of ‘Systems Thinking’ to Action Research 总被引:7,自引:7,他引:0
Robert Louis Flood 《Systemic Practice and Action Research》2010,23(4):269-284
This article investigates the relationship of systems thinking to action research by reviewing the main developments in systems
thinking and relating these to action research. There are two main lines of thought in systems thinking that lead to wholly
different conceptions about action research. The first (systems thinking) advocates thinking about real social systems that
it assumes exist in the world. The second (systemic thinking) supposes only that the social construction of the world is systemic.
Greater emphasis is placed on systemic thinking consistent with its greater importance to contemporary action research. The
article concludes that systemic thinking when taken to its practical conclusion from a critical perspective offers to action
research a somewhat unique liberating praxis. Concern that any liberating praxis could remain hollow is addressed through
a certain kind of ‘spiritual’ awareness that is suggested by wholeness. 相似文献
65.
Possible Implications of the Quantum Theory of Gravity: An Introduction to the Meduso-Anthropic Principle 总被引:1,自引:1,他引:0
Louis Crane 《Foundations of Science》2010,15(4):369-373
If we assume that the constants of nature fluctuate near the singularity when a black hole forms (assuming, also, that physical
black holes really do form singularities) then a process of evolution of universes becomes possible. We explore the implications
of such a process for the origin of life, interstellar travel, and the human future. 相似文献
66.
67.
澳大利亚麦龙虾触角腺组织学的初步研究 总被引:3,自引:0,他引:3
本文首次报道了以组织学手段对澳大利亚淡水螯虾-麦龙虾的触角腺进行研究的结果。根据组织学(?)征麦龙虾的触角腺可分为三个部分,它们依次为:端囊,迷路和肾管。端囊部分的细胞呈柱状,细胞核位于基部或中部。迷路部分的细胞呈短柱状,顶端有刷状缘,核位于基部或亚中部。肾管部分的细胞扁平,核很大偏向顶端,占据了细胞的大部分空间。在迷路和肾管部分没有明显的亚区的分别。 相似文献
68.
Prediction of central nervous system embryonal tumour outcome based on gene expression. 总被引:75,自引:0,他引:75
Scott L Pomeroy Pablo Tamayo Michelle Gaasenbeek Lisa M Sturla Michael Angelo Margaret E McLaughlin John Y H Kim Liliana C Goumnerova Peter M Black Ching Lau Jeffrey C Allen David Zagzag James M Olson Tom Curran Cynthia Wetmore Jaclyn A Biegel Tomaso Poggio Shayan Mukherjee Ryan Rifkin Andrea Califano Gustavo Stolovitzky David N Louis Jill P Mesirov Eric S Lander Todd R Golub 《Nature》2002,415(6870):436-442
Embryonal tumours of the central nervous system (CNS) represent a heterogeneous group of tumours about which little is known biologically, and whose diagnosis, on the basis of morphologic appearance alone, is controversial. Medulloblastomas, for example, are the most common malignant brain tumour of childhood, but their pathogenesis is unknown, their relationship to other embryonal CNS tumours is debated, and patients' response to therapy is difficult to predict. We approached these problems by developing a classification system based on DNA microarray gene expression data derived from 99 patient samples. Here we demonstrate that medulloblastomas are molecularly distinct from other brain tumours including primitive neuroectodermal tumours (PNETs), atypical teratoid/rhabdoid tumours (AT/RTs) and malignant gliomas. Previously unrecognized evidence supporting the derivation of medulloblastomas from cerebellar granule cells through activation of the Sonic Hedgehog (SHH) pathway was also revealed. We show further that the clinical outcome of children with medulloblastomas is highly predictable on the basis of the gene expression profiles of their tumours at diagnosis. 相似文献
69.
The prairie skink, Eumeces septentrionalis , is a small, semifossorial lizard inhabiting the tall-grass prairies and savannas of the central lowland province region of North America. This study provides an extensive bibliography and subject index as a tool for current and future workers studying E. septentrionalis and related species. 相似文献
70.
Counts of Double-crested Cormorants ( Phalacrocorax auritus ) were made at 13 reservoirs and lakes in southwestern Utah during 1989-91 to determine current abundance of that species. Food habits of cormorants were studied at three of the reservoirs in 1989. Data were also collected on trout abundance during standardized gill-netting to make comparisons between cormorant numbers and trout abundance. Cormorants were observed at all waters studied except one and were generally most numerous during the spring as they migrated through the area. Estimated cormorant abundance ranged from 0 to 34 bird-days per ha and was highest at the larger, lower-elevation reservoirs. Cormorants were summer residents at several of the larger reservoirs and nested successfully at Piute Reservoir. Trout accounted for 24-81% of the diet of cormorants, with Utah chubs constituting most of the remainder of the diet. Estimates of the annual consumption of fish by cormorants ranged from 0 to 15.8 kg per ha. The index of trout abundance was inversely related to cormorant abundance ( P < .01) at the waters studied. Cormorants apparently have increased in numbers and extended their range in southwestern Utah during the past decade. This change may be the result of factors that have led to similar changes throughout North America as well as some factors unique to Utah. Methods to mitigate the impact of predation by piscivorous birds of sportfisheries are discussed. The Utah Division of Wildlife Resources has initiated a new management plan at Minersville Reservoir that incorporates piscivorous birds into sportfish management at that reservoir. 相似文献