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排序方式: 共有588条查询结果,搜索用时 31 毫秒
31.
Stefan J. Erkeland Christiaan J. Stavast Joyce Schilperoord-Vermeulen Giada Dal Collo Harmen J.G. van de Werken Leticia G. Leon Antoinette van Hoven-Beijen Iris van Zuijen Yvonne M. Mueller Eric M. Bindels Dick de Ridder Mies C. Kappers-Klunne Kirsten van Lom Vincent H.J. van der Velden Anton W. Langerak 《Haematologica》2022,107(1):143
T-cell prolymphocytic leukemia (T-PLL) is mostly characterized by aberrant expansion of small- to medium-sized prolymphocytes with a mature post-thymic phenotype, high aggressiveness of the disease and poor prognosis. However, T-PLL is more heterogeneous with a wide range of clinical, morphological, and molecular features, which occasionally impedes the diagnosis. We hypothesized that T-PLL consists of phenotypic and/or genotypic subgroups that may explain the heterogeneity of the disease. Multi-dimensional immuno-phenotyping and gene expression profiling did not reveal clear T-PLL subgroups, and no clear T-cell receptor a or b CDR3 skewing was observed between different T-PLL cases. We revealed that the expression of microRNA (miRNA) is aberrant and often heterogeneous in T-PLL. We identified 35 miRNA that were aberrantly expressed in T-PLL with miR-200c/141 as the most differentially expressed cluster. High miR- 200c/141 and miR-181a/181b expression was significantly correlated with increased white blood cell counts and poor survival. Furthermore, we found that overexpression of miR-200c/141 correlated with downregulation of their targets ZEB2 and TGFbR3 and aberrant TGFb1- induced phosphorylated SMAD2 (p-SMAD2) and p-SMAD3, indicating that the TGFb pathway is affected in T-PLL. Our results thus highlight the potential role for aberrantly expressed oncogenic miRNA in T-PLL and pave the way for new therapeutic targets in this disease. 相似文献
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Test‐retest reliability of the default mode network in a multi‐centric fMRI study of healthy elderly: Effects of data‐driven physiological noise correction techniques 下载免费PDF全文
Rocco Marchitelli Ludovico Minati Moira Marizzoni Beatriz Bosch David Bartrés‐Faz Bernhard W. Müller Jens Wiltfang Ute Fiedler Luca Roccatagliata Agnese Picco Flavio Nobili Oliver Blin Stephanie Bombois Renaud Lopes Régis Bordet Julien Sein Jean‐Philippe Ranjeva Mira Didic Hélène Gros‐Dagnac Pierre Payoux Giada Zoccatelli Franco Alessandrini Alberto Beltramello Núria Bargalló Antonio Ferretti Massimo Caulo Marco Aiello Carlo Cavaliere Andrea Soricelli Lucilla Parnetti Roberto Tarducci Piero Floridi Magda Tsolaki Manos Constantinidis Antonios Drevelegas Paolo Maria Rossini Camillo Marra Peter Schönknecht Tilman Hensch Karl‐Titus Hoffmann Joost P. Kuijer Pieter Jelle Visser Frederik Barkhof Jorge Jovicich 《Human brain mapping》2016,37(6):2114-2132
Understanding how to reduce the influence of physiological noise in resting state fMRI data is important for the interpretation of functional brain connectivity. Limited data is currently available to assess the performance of physiological noise correction techniques, in particular when evaluating longitudinal changes in the default mode network (DMN) of healthy elderly participants. In this 3T harmonized multisite fMRI study, we investigated how different retrospective physiological noise correction (rPNC) methods influence the within‐site test‐retest reliability and the across‐site reproducibility consistency of DMN‐derived measurements across 13 MRI sites. Elderly participants were scanned twice at least a week apart (five participants per site). The rPNC methods were: none (NPC), Tissue‐based regression, PESTICA and FSL‐FIX. The DMN at the single subject level was robustly identified using ICA methods in all rPNC conditions. The methods significantly affected the mean z‐scores and, albeit less markedly, the cluster‐size in the DMN; in particular, FSL‐FIX tended to increase the DMN z‐scores compared to others. Within‐site test‐retest reliability was consistent across sites, with no differences across rPNC methods. The absolute percent errors were in the range of 5–11% for DMN z‐scores and cluster‐size reliability. DMN pattern overlap was in the range 60–65%. In particular, no rPNC method showed a significant reliability improvement relative to NPC. However, FSL‐FIX and Tissue‐based physiological correction methods showed both similar and significant improvements of reproducibility consistency across the consortium (ICC = 0.67) for the DMN z‐scores relative to NPC. Overall these findings support the use of rPNC methods like tissue‐based or FSL‐FIX to characterize multisite longitudinal changes of intrinsic functional connectivity. Hum Brain Mapp 37:2114–2132, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
34.
Rosario Caltabiano Gaetano Magro Giada Maria Vecchio Salvatore Lanzafame 《Journal of cutaneous pathology》2010,37(2):287-291
We first report a case of granular cell histiocytosis occurring as a solitary polypoid lesion of the nipple in a 15‐year‐old girl. Histologically, the lesion was composed of a dermal population of medium‐ to large‐sized, short spindle‐ to round‐ to epithelioid‐shaped cells with eosinophilic cytoplasm containing numerous and small diastase‐resistant periodic acid‐Schiff (PAS) positive granules. No associated inflammatory cells were observed. Immunohistochemical studies, revealing immunoreactivity exclusively to vimentin and CD68, were consistent with their histiocytic profile. Based on clinical, morphological and immunohistochemical features, the diagnosis of ‘solitary cutaneous histiocytosis with granular cell changes’ was proposed. The absence of an inflammatory cell component, such as lymphocytes and leucocytes, along with no history of a previous trauma or medical treatment, suggest that the present lesion could fit into the morphological spectrum of the so‐called solitary epithelioid histiocytoma, also known as reticulohistiocytoma. Alternatively, the possibility of a histiocytic reaction to unknown stimuli cannot be completely ruled out. Nevertheless, awareness of solitary cutaneous histiocytosis with granular cell changes is useful to avoid confusion with other dermal tumors, especially ‘granular cell tumor’ and ‘dermal non‐neural granular cell tumor’. Caltabiano R, Magro G, Vecchio GM, Lanzafame S. Solitary cutaneous histiocytosis with granular cell changes: a morphological variant of reticulohistiocytoma? 相似文献
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Drug resistance mutations in the nucleotide binding pocket of human immunodeficiency virus type 1 reverse transcriptase differentially affect the phosphorolysis-dependent primer unblocking activity in the presence of stavudine and zidovudine and its inhibition by efavirenz 总被引:2,自引:0,他引:2 下载免费PDF全文
Crespan E Locatelli GA Cancio R Hübscher U Spadari S Maga G 《Antimicrobial agents and chemotherapy》2005,49(1):342-349
38.
Conti S Meli P Minelli G Solimini R Toccaceli V Vichi M Beltrano MC Perini L 《Igiene e sanità pubblica》2004,60(3):121-139
Following the unusually hot summer this year and the dramatic news from neighboring countries such as France, the Italian Minister of Health requested an epidemiologic mortality study during summer 2003, to investigate whether there had been an excess of deaths in Italy, particularly for the elderly population. Communal offices, which provide vital statistics, were asked for the number of deaths among resident people, occurred from June 1 to August 31, for 2003 and 2002, for the 21 Italian regions capitals. A mortality increase of 3,134 deaths was observed for 2003; most of them (92%) were people aged 75 years and older. The highest increases were observed in the North Western cities (Turin, Milan, Genoa). The relationship between mortality and climatic indexes (T. max, Humidex) was investigated and a clear correlation was observed. 相似文献
39.
Thornton PD Fernandez C Giustolisi GM Morilla R Atkinson S A'Hern RP Matutes E Catovsky D 《The hematology journal : the official journal of the European Haematology Association / EHA》2004,5(2):145-151
Staging systems and laboratory features help predict survival in chronic lymphocytic leukaemia but they do not distinguish patients who will progress from those whose disease will remain indolent. CD38 expression has emerged as an independent prognostic factor, yet there is debate as to what level of CD38 affects prognosis. We plotted the hazard ratios for the treatment-free interval (TFI) between the higher and lower groups defined by CD38 cut-offs from 0 to 100%. The maximum hazard ratio was achieved for a cut-off of 7%. We examined by triple colour analysis the values for CD38 in 289 untreated patients using both >or=30 and >or=7% as thresholds for prognosis. Using a >or=7% threshold (but not >or=30%), we showed a significant correlation with advanced stage and male sex. The interval from diagnosis to first therapy or TFI was longer (median 36 months) in patients with <7% CD38 positive cells than those with >or= 30% (8.7 months) or with intermediate values between 7 and 29% (P<0.00005). The <7% threshold also identified patients in stage A with a long TFI (P=0.0001). Multivariate analysis showed that CD38 has independent prognostic value for TFI in all patients. In 135 patients tested for deletions of p53, 13q14 and 11q23 and for trisomy 12, we showed a correlation between 13q14 deletion and <30%/<7% CD38 positive cells and a tendency for trisomy 12 to be associated with >or=30%/>or=7% CD38 positive cells. We conclude that 7% may be a more useful threshold for disease progression than higher values of CD38. 相似文献
40.
Regoli F Frenzilli G Bocchetti R Annarumma F Scarcelli V Fattorini D Nigro M 《Aquatic toxicology (Amsterdam, Netherlands)》2004,68(2):167-178
Harbours can be considered as model environments for developing and validating field monitoring procedures and to investigate mechanistic relationships between different biological responses. In this study, several biomarkers were investigated in marine mussels caged for 4 weeks into an industrialised harbour of north-west Italy. Organisms were collected at different time intervals to better characterise the sensitivity, temporal variations and interactions of analysed responses. Besides single antioxidants (catalase, glutathione S-transferases, glutathione reductase, total glutathione), the total oxyradical scavenging capacity (TOSC) assay was used to analyse the capability of the whole antioxidant system to neutralise specific forms of radicals: these data were further integrated by measurement of DNA integrity, oxidised bases and the impairment of lysosomal membrane stability in haemocytes. Results showed a biphasic trend for single antioxidants and TOSC, with no variation or increase during the first 2 weeks of exposure to the polluted site followed by a progressive decrease up to a severe depletion in the final part of the experiment. These findings suggest an initial counteractive response of mussels toward the enhanced prooxidant challenge, while antioxidants appeared overwhelmed at longer exposure periods. The hypothesis of reactive oxygen species (ROS) mediated toxicity is supported by the appearance of cell damages (DNA integrity and lysosome membrane stability), which exhibited a progressive enhancement during the course of the experiment with a maximum impairment after 30 days of exposure. 相似文献