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Several protocols have illustrated the possibility of deriving cells, such as fibroblasts, from different organs. These techniques generally concern organs sampled from living persons, but have already been described for cadavers, especially concerning the skin and tendons. We present, for the first time, an easy way to derive pulmonary fibroblasts from a lung tissue sampled from a cadaver and directly culture plated. The fibroblast output was checked daily. We obtained lung fibroblasts from 3 (60%) cadavers and 2 (100%) living persons. The fibroblast output took about 3 days for cells from living persons and took up to 39 days for those from cadavers. We did not clearly identify any parameters that could explain these differences. Nevertheless, these derived cells had the same features as the source cells, especially in terms of morphology and proliferation, and could potentially be used in different research domains such as forensic or regeneration medicine.  相似文献   
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This conceptual paper investigates the common concern among managers that the physical separation of workers within a global virtual team may hinder the transfer of knowledge amongst the team members that is required to carry out their work efficiently, especially in the context of knowledge-intensive enterprises. Workers and work teams in knowledge-intensive enterprises are often involved in creative tasks that are carried out jointly and involve team members with diversified competencies exchanging knowledge related to their projects and assignments to create innovative outcomes. We investigate some popular creativity-enhancing techniques in the perspective of their use as catalysts for knowledge transfer in this context. We assess whether the use of these techniques may alleviate the limitations imposed on global virtual team members by their use of telecommunications and collaborative work tools that might otherwise adversely affect the effectiveness of the knowledge transfer. These techniques are designed to be used individually, by groups or within a virtual community. The physical and temporal separation of the global virtual team members does not hinder the knowledge-intensive dimension of these enterprises when aided by creativity-stimulating techniques. Therefore, we suggest that global virtual teams making use of creativity-enhancing techniques may be more efficient in transferring complex knowledge.  相似文献   
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The aim of this study was to evaluate postmortem incorporation of opiates in bone and bone marrow after diacetylmorphine (heroin) administration to mice. Mice were given acute (lethal dose of 300 mg/kg) or chronic (10 and 20 mg/kg/24 h for 20 days) intraperitoneal administration of diacetylmorphine. The two metabolites of diacetylmorphine, 6-acetylmorphine (6-AM) and morphine, were extracted from whole blood, brain, spinal cord, bone marrow and bone (after hydrolysis) using a liquid/liquid method. Quantification was performed by gas chromatography-mass spectrometry (GC/MS). Results showed that after acute administration, opiates were present in all studied tissues. Morphine concentrations appeared to be higher than those of 6-AM in blood (52.4 microg/mL versus 27.7 microg/mL, n=12), bone marrow (87.8 ng/mg versus 8.9 ng/mg, n=6) and bone (0.85 ng/mg versus 0.43 ng/mg, n=6), but 6-AM concentrations were higher than those of morphine in brain (14.0 ng/mg versus 7.4 ng/mg, n=12) and spinal cord (27.8 ng/mg versus 20.8 ng/mg, n=12). No correlation was found for both compounds between blood concentrations and either brain, spinal cord, bone or bone marrow concentrations while a significant one was found between brain and spinal cord concentrations either for morphine (r=0.89, n=12, p<0.001) or 6-AM (r=0.93, n=12, p<0.001), the concentration being higher in spinal cord than in brain. When bones were stored for 2 months, only 6-AM remained in bone marrow but not in bone. After chronic administration, mice being sacrificed by cervical dislocation 24 h after the last injection, no opiate was detected in any studied tissues. Further studies are required, in particular in human bones, but these results seem to show that 6-AM could be detect in bone marrow several weeks after the death and could be an alternative tissue for forensic toxicologist to detect a fatal diacetylmorphine overdose, even if no correlation between blood and bone marrow was observed. On the other hand, neither bone tissue nor bone marrow will allow the confirmation of a chronic diacetylmorphine use.  相似文献   
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Eight Y chromosome short tandem repeats (STR) loci (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385I/II) were used to assess haplotype distribution in non-selected, unrelated Bantu males living in Central Africa [N. Mathias, M. Bayes, C. Tyler-Smith, Highly informative compound haplotypes for the human Y chromosome, Hum. Mol. Genet. 3 (1994) 115-123; L. Roewer, J. Arnemann, N.K. Spurr, K.H. Grzeschik, J.T. Epplen, Simple repeat sequences on the human Y chromosome are equally polymorphic as their autosomal counterparts, Hum. Genet. 89 (1992) 389-394; P. De Knijff, M. Kayser, A. Caglia, D. Corach, N. Fretwel, C. Gehrig, G. Graziosi, F. Heidorn, S. Herrmann, B. Herzog, M. Hidding, K. Honda, M. Jobling, M. Krawczak, K. Leim, S. Meuser, E. Meyer, W. Oesterreich, A. Pandya, W. Parson, G. Penacino, A. Perez-Lezaun, A. Piccini, M. Prinz, C. Schmitt, P. M. Schneider, R. Szibor, J. Teifel-Greding, G. Weishold, L. Rower, Chromosome Y microsatellites: population genetic and evolutionary aspects, Int. J. Legal Med. 110 (1997) 134-149; M. Kayser, A. Caglia, D. Corach, N. Fretwel, C. Gehrig, G. Graziosi, F. Heidorn, S. Herrmann, B. Herzog, M. Hidding, K. Honda, M. Jobling, M. Krawczak, K. Leim, S. Meuser, E. Meyer, W. Oesterreich, A. Pandya, W. Parson, G. Penacino, A. Perez-Lezaun, A. Piccini, M. Prinz, C. Schmitt, P. M. Schneider, R. Szibor, J. Teifel-Greding, G. Weishold, P. de Knijff, L. Rower, Evaluation of Y chromosome STRs: a multicenter study, Int. J. Legal Med. 110 (1997) 125-133, 141-149]. One hundred and sixty-five full haplotypes were obtained from Bantu males. The most common haplotype (DYS19-15, DYS389I-13, DYS389II-30, DYS390-21, DYS391-10, DYS392-11, DYS393-13, DYS385I/II-15,17) was shared by 5.5% of individuals. In the Bantu population in Central Africa, the haplotype diversity and the discrimination capacity of Y-STR may be estimated at 99.14% and 0.5333, respectively.  相似文献   
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This article introduces the rationale for the special issue, summarizes the main themes covered by the papers presented and suggests areas for further research. Previous research has focused on the creation of Science-based entrepreneurial firms (SBEFs) but there is little research relating to their growth and the challenges in ensuring growth occurs. At the macro-level, there is a need to distinguish general versus specific policies and how these vary between different institutional environments. At the firm level, there is a need to consider the factors influencing the development of boards, the growth of SBEFs and their dynamics in terms of acquisitions and IPOs.  相似文献   
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In his 1975 paper, Nordhaus formally proves that governments whose aim is to be reelected, will generate ‘political’ business cycles. Empirical results do not confirm this proposition, especially in countries used to early elections. We show that if there is a non-zero probability for elections to be called before the legal term, the political business cycle will be less pronounced, even if no early election actually takes place; moreover, if the normal electoral cycle is interrupted before the legal term, one might observe an inversion of the business cycle, or no cycle at all.  相似文献   
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