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Werner Ulrich 《Systemic Practice and Action Research》1988,1(4):415-428
Churchman's process of unfolding is one of his lesser known concepts, yet it is essential for understanding his dialectical systems approach. This paper gives a brief introduction to the concept and presents a simple framework for applying it to policy analysis and program evaluation. 相似文献
34.
This is a testament to conversations held in Berne and Fribourg, Switzerland, in late 1988. The main theme that we present concerns seeking to find an adequate epistemology for systems practice, to find a truly critical approach, by shifting our interests from systems science to systems rationality (i.e., by reaching out toward a systems epistemological ideal) and by dealing with sociological phenomena such as the effects of material conditions and false consciousness and inequalities associated with these. Social rationalities relating to positivism, interpretivism, and critique are considered. Limitations and legitimacies of these rationalities in social contexts are made explicit in these discussions.Conversations were held in Berne and Fribourg, Switzerland, between 30 November and 5 December 1988. 相似文献
35.
Characterization of murine non-adherent bone marrow cells leading to recovery of endogenous hematopoiesis 总被引:1,自引:1,他引:0
Stephan Fricke Christian Fricke Christopher Oelkrug Nadja Hilger Uta Sch?nfelder Manja Kamprad J?rg Lehmann Johannes Boltze Frank Emmrich Ulrich Sack 《Cellular and molecular life sciences : CMLS》2010,67(23):4095-4106
Non-adherent bone marrow-derived cells (NA-BMCs) are a mixed cell population that can give rise to multiple mesenchymal phenotypes
and that facilitates hematopoietic recovery. We characterized NA-BMCs by flow cytometry, fibroblast colony-forming units (CFU-f),
real-time PCR, and in in vivo experiments. In comparison to adherent cells, NA-BMCs expressed high levels of CD11b+ and CD90+ within the CD45+ cell fraction. CFU-f were significantly declining over the cultivation period, but NA-BMCs were still able to form CFU-f
after 5 days. Gene expression analysis of allogeneic NA-BMCs compared to bone marrow (BM) indicates that NA-BMCs contain stromal,
mesenchymal, endothelial cells and monocytes, but less osteoid, lymphoid, and erythroid cells, and hematopoietic stem cells.
Histopathological data and analysis of weight showed an excellent recovery and organ repair of lethally irradiated mice after
NA-BMC transplantation with a normal composition of the BM. 相似文献
36.
Tamara Jefferson Ulrich auf dem Keller Caroline Bellac Verena V. Metz Claudia Broder Jana Hedrich Anke Ohler Wladislaw Maier Viktor Magdolen Erwin Sterchi Judith S. Bond Arumugam Jayakumar Heiko Traupe Athena Chalaris Stefan Rose-John Claus U. Pietrzik Rolf Postina Christopher M. Overall Christoph Becker-Pauly 《Cellular and molecular life sciences : CMLS》2013,70(2):309-333
The in vivo roles of meprin metalloproteases in pathophysiological conditions remain elusive. Substrates define protease roles. Therefore, to identify natural substrates for human meprin α and β we employed TAILS (terminal amine isotopic labeling of substrates), a proteomics approach that enriches for N-terminal peptides of proteins and cleavage fragments. Of the 151 new extracellular substrates we identified, it was notable that ADAM10 (a disintegrin and metalloprotease domain-containing protein 10)—the constitutive α-secretase—is activated by meprin β through cleavage of the propeptide. To validate this cleavage event, we expressed recombinant proADAM10 and after preincubation with meprin β, this resulted in significantly elevated ADAM10 activity. Cellular expression in murine primary fibroblasts confirmed activation. Other novel substrates including extracellular matrix proteins, growth factors and inhibitors were validated by western analyses and enzyme activity assays with Edman sequencing confirming the exact cleavage sites identified by TAILS. Cleavages in vivo were confirmed by comparing wild-type and meprin?/? mice. Our finding of cystatin C, elafin and fetuin-A as substrates and natural inhibitors for meprins reveal new mechanisms in the regulation of protease activity important for understanding pathophysiological processes. 相似文献
37.
Ellinghaus E Ellinghaus D Stuart PE Nair RP Debrus S Raelson JV Belouchi M Fournier H Reinhard C Ding J Li Y Tejasvi T Gudjonsson J Stoll SW Voorhees JJ Lambert S Weidinger S Eberlein B Kunz M Rahman P Gladman DD Gieger C Wichmann HE Karlsen TH Mayr G Albrecht M Kabelitz D Mrowietz U Abecasis GR Elder JT Schreiber S Weichenthal M Franke A 《Nature genetics》2010,42(11):991-995
38.
Melum E Franke A Schramm C Weismüller TJ Gotthardt DN Offner FA Juran BD Laerdahl JK Labi V Björnsson E Weersma RK Henckaerts L Teufel A Rust C Ellinghaus E Balschun T Boberg KM Ellinghaus D Bergquist A Sauer P Ryu E Hov JR Wedemeyer J Lindkvist B Wittig M Porte RJ Holm K Gieger C Wichmann HE Stokkers P Ponsioen CY Runz H Stiehl A Wijmenga C Sterneck M Vermeire S Beuers U Villunger A Schrumpf E Lazaridis KN Manns MP Schreiber S Karlsen TH 《Nature genetics》2011,43(1):17-19
Primary sclerosing cholangitis (PSC) is a chronic bile duct disease affecting 2.4-7.5% of individuals with inflammatory bowel disease. We performed a genome-wide association analysis of 2,466,182 SNPs in 715 individuals with PSC and 2,962 controls, followed by replication in 1,025 PSC cases and 2,174 controls. We detected non-HLA associations at rs3197999 in MST1 and rs6720394 near BCL2L11 (combined P = 1.1 × 10?1? and P = 4.1 × 10??, respectively). 相似文献
39.
We explore the benefits of forecast combinations based on forecast‐encompassing tests compared to simple averages and to Bates–Granger combinations. We also consider a new combination algorithm that fuses test‐based and Bates–Granger weighting. For a realistic simulation design, we generate multivariate time series samples from a macroeconomic DSGE‐VAR (dynamic stochastic general equilibrium–vector autoregressive) model. Results generally support Bates–Granger over uniform weighting, whereas benefits of test‐based weights depend on the sample size and on the prediction horizon. In a corresponding application to real‐world data, simple averaging performs best. Uniform averages may be the weighting scheme that is most robust to empirically observed irregularities. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
40.
Ulrich Hoyer 《Archive for History of Exact Sciences》1980,23(1):47-86
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S. Flügge 相似文献