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排序方式: 共有3474条查询结果,搜索用时 15 毫秒
71.
MicroRNA signatures characterize diffuse large B-cell lymphomas and follicular lymphomas 总被引:1,自引:1,他引:1
Roehle A Hoefig KP Repsilber D Thorns C Ziepert M Wesche KO Thiere M Loeffler M Klapper W Pfreundschuh M Matolcsy A Bernd HW Reiniger L Merz H Feller AC 《British journal of haematology》2008,142(5):732-744
MicroRNAs (miRNA, miR) are negative regulators of gene expression that play an important role in diverse biological processes such as development, cell growth, apoptosis and haematopoiesis, suggesting their association with cancer. Here we analysed the expression signatures of 157 miRNAs in 58 diffuse large B-cell lymphoma (DLBCL), 46 follicular lymphoma (FL) and seven non-neoplastic lymph nodes (LN). Comparison of the possible combinations of DLBCL-, FL- and LN resulted in specific DLBCL- and FL-signatures, which include miRNAs with previously published function in haematopoiesis ( MIRN150 and MIRN155 ) or tumour development ( MIRN210 , MIRN10A , MIRN17-5P and MIRN145 ). As compared to LN, some miRNAs are differentially regulated in both lymphoma types ( MIRN155 , MIRN210 , MIRN106A , MIRN149 and MIRN139 ). Conversely, some miRNAs show lymphoma-specific aberrant expression, such as MIRN9/9* , MIRN301 , MIRN338 and MIRN213 in FL and MIRN150 , MIRN17-5P , MIRN145 , MIRN328 and others in DLBCL. A classification tree was computed using four miRNAs ( MIRN330 , MIRN17-5P , MIRN106a and MIRN210 ) to correctly identify 98% of all 111 cases that were analysed in this study. Finally, eight miRNAs were found to correlate with event-free and overall survival in DLBCL including known tumour suppressors ( MIRN21 , MIRN127 and MIRN34a ) and oncogenes ( MIRN195 and MIRNLET7G ). 相似文献
72.
Differentiation of in vitro-modified human peripheral blood monocytes into hepatocyte-like and pancreatic islet-like cells 总被引:16,自引:0,他引:16
73.
Influence of different trigger techniques on twitch mouth pressure during bilateral anterior magnetic phrenic nerve stimulation 总被引:4,自引:0,他引:4
BACKGROUND: The trigger has a key role when assessing the twitch mouth pressure (Tw Pmo), since a "gentle" inspiratory or expiratory effort is needed for triggering to ensure an open glottis during twitch, but which also guarantees only very mild changes of transdiaphragmatic pressure following changes in lung volume. STUDY OBJECTIVES: To test if different trigger mechanisms cause different Tw Pmo values, if the predefined trigger criteria were accomplished, and if the breathing maneuver during triggering can influence the Tw Pmo. DESIGN: Experimental study. SETTING: Respiratory muscle and lung function laboratory of a university hospital. PARTICIPANTS: Twenty healthy men (mean age, 25.6 +/- 1.2 years [+/- SD]; mean FEV(1), 105.9 +/- 11.5% of predicted). MEASUREMENTS: Tw Pmo produced by bilateral anterior magnetic phrenic nerve stimulation was measured using an inspiratory flow trigger (40 mL/s), an inspiratory pressure trigger, and an expiratory pressure trigger (3.75 mm Hg). All trigger criteria were controlled. RESULTS: Unusable pressure-time curves occurred in 40% during expiratory triggering, but not during inspiratory triggering. For inspiratory pressure (flow) triggering, 10% (30%) of the predefined trigger criteria were exceeded by 50%, indicating that a "gentle" inspiratory effort was not warranted. The Tw Pmo was higher during inspiratory compared to expiratory triggering (analysis of variance, p < 0.05). The Tw Pmo during inspiratory pressure and flow triggering were comparable and significantly correlated (r = 0.70, p < 0.0001). The time between start of inspiration and trigger release, and the pressure-time product during that period ranged widely, but this could not predict the Tw Pmo (multiple linear regression). CONCLUSIONS: The trigger technique influences the Tw Pmo with higher values during inspiratory compared to expiratory triggering. Expiratory triggering more often produced unusable pressure-time curves. Inspiratory flow and pressure triggering is comparably useful in healthy subjects, but this might be different in patients. The trigger criteria need to be controlled to warrant a gentle breathing effort. 相似文献
74.
75.
Kreitschmann-Andermahr Ilonka Siegel Sonja Unger Nicole Streetz-van der Werf Christine Karges Wolfram Schilbach Katharina Schröder Bernadette Szybowicz Janine Sauerwald Janina Zopf Kathrin Grzywotz Agnieszka Bidlingmaier Martin Sommer Heide Strasburger Christian J. 《Pituitary》2020,23(5):479-487
Pituitary - While reasons for non-adherence in children requiring growth hormone (GH) replacement (GH-Rx) are well researched, few studies have investigated adherence in adult GH deficient... 相似文献
76.
Ines Lichtmannegger Stefan Gölder Andreas Probst Günay Dönmez Abbas Agaimy Erich Langer Wolfram Müller Lanjing Zhang Hanno Spatz Bruno Märkl 《Virchows Archiv : an international journal of pathology》2014,465(3):257-264
Fibroelastotic changes (FEC) and especially elastotic polyps of the gastrointestinal (GI) tract are considered rare benign lesions. They consist of accumulations of elastic fibers within the mucosal, submucosal, or muscular layer, occurring in all parts of the GI tract and often appearing as polyps, but also as diffuse non-polyp-forming deposits. They have been the subject of only a few studies. To explore the clinical and histopathological features of FEC in the GI tract, a series of 162 elastotic lesions was collected within a 2-year period. The clinical data and endoscopic findings were correlated. FEC appeared as polyp-forming lesions of the large intestine in 23 samples (14 %), all other samples concerning histological findings without an identifiable gross mass. Frequently related findings were postinterventional status (9 %), previous irradiation (7 %), and history of GI lymphoma (4 %). Eight samples (5 %) presented endoscopically with lesions justifying surgical intervention. We identified three different histological patterns of FEC, which we have called fibroelastosis, angioelastosis, and elastofibroma. Consistent with previous studies, CD34 immunohistochemical staining (performed on 38 polypoid FEC specimens) showed an increase of CD34-positive mesenchymal cells in 95 % of immunostained samples, suggesting a potential role for CD34-positive mesenchymal cells in the accumulation of elastic fibers. In conclusion, FEC are more common in the GI tract than previously recognized. They often present as a benign polyp. Many accompany other diseases like ulcers and atrophic gastritis or represent a residual finding after an intervention. 相似文献
77.
Suthaus J Stuhlmann-Laeisz C Tompkins VS Rosean TR Klapper W Tosato G Janz S Scheller J Rose-John S 《Blood》2012,119(22):5173-5181
Human herpes virus 8 (HHV-8) or Kaposi sarcoma-associated herpes virus is the etiologic agent of Kaposi sarcoma, primary effusion lymphoma, and plasma cell-type multicentric Castleman disease (MCD). HHV-8 encodes a viral homolog of human IL-6, called viral IL-6 (vIL-6), which does not require the cellular IL-6 receptor for binding to the ubiquitously expressed gp130 receptor subunit and subsequent JAK-STAT signaling. Thus, in contrast to IL-6, vIL-6 can stimulate virtually all cells in the body. To elucidate the mechanism by which vIL-6 drives human diseases, we generated transgenic mice that constitutively express vIL-6 under control of the MHC class I promoter. The mice were found to exhibit vIL-6 serum levels comparable with those observed in HHV-8-infected patients, to contain elevated amounts of phosphorylated STAT3 in spleen and lymph nodes, where vIL-6 was produced, and to spontaneously develop key features of human plasma cell-type MCD, including splenomegaly, multifocal lymphadenopathy, hypergammaglobulinemia, and plasmacytosis. Transfer of the vIL-6 transgene onto an IL-6-deficient genetic background abrogated MCD-like phenotypes, indicating that endogenous mouse IL-6 is a crucial cofactor in the natural history of the disease. Our results in mice suggest that human IL-6 plays an important role in the pathogenesis of HHV-8-associated MCD. 相似文献
78.
79.
Stephan von Haehling Joerg C. Schefold Ewa A. Jankowska Jochen Springer Ali Vazir Paul R. Kalra Anja Sandek Günter Fauler Tatjana Stojakovic Michael Trauner Piotr Ponikowski Hans-Dieter Volk Wolfram Doehner Andrew J.S. Coats Philip A. Poole-Wilson Stefan D. Anker 《Journal of the American College of Cardiology》2012
80.
Maria Auer Ilary Allodi Mohammed Barham Esther Udina Wolfram F. Neiss Xavier Navarro Lars Klimaschewski 《Journal of the peripheral nervous system : JPNS》2013,18(1):30-36
Peripheral nerve injury triggers the activation of the small GTPase RhoA in spinal motor and peripheral sensory neurons. C3 transferase, an exoenzyme produced by Clostridium botulinum that inactivates RhoA by ADP‐ribosylation, has been successfully applied in central nervous system (CNS) lesion models to facilitate regeneration functionally and morphologically. Until now it has not been demonstrated if C3bot exerts positive effects on peripheral axon regeneration as well. In organotypic spinal cord preparations, C3bot reduced axonal growth of motoneurons, while no effect on sensory axon outgrowth from dorsal root ganglia (DRG) explants was observed. Enzymatically inactive C3E174Q was ineffective in both culture models. Spinal cord slices exhibited a significant increase in microglia/macrophages after treatment with C3bot suggesting an inflammatory component in the inhibition of axon growth. C3bot or C3E174Q were then applied into conduits implanted after transection of the sciatic nerve in rats. Functional evaluation by electrophysiology, nociception, and walking track tests did not show any significant difference between groups with active or mutant C3E174Q. Transmission electron microscopy of the regenerated nerves revealed no significant differences in the number of myelinated and unmyelinated axons 6 weeks after surgery. Compared to the CNS, the functional significance of RhoA may be limited during nerve regeneration in a growth‐promoting environment. 相似文献