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81.
Tacchini-Cottier F Allenbach C Otten LA Radtke F 《European journal of immunology》2004,34(6):1588-1596
Notch1 proteins are involved in binary cell fate decisions. To determine the role of Notch1 in the differentiation of CD4(+) Th1 versus Th2 cells, we have compared T helper polarization in vitro in naive CD4(+) T cells isolated from mice in which the N1 gene is specifically inactivated in all mature T cells. Following activation, Notch1-deficient CD4(+) T cells transcribed and secreted IFN-gamma under Th1 conditions and IL-4 under Th2 conditions at levels similar to that of control CD4(+) T cells. These results show that Notch1 is dispensable for the development of Th1 and Th2 phenotypes in vitro. The requirement for Notch1 in Th1 differentiation in vivo was analyzed following inoculation of Leishmania major in mice with a T cell-specific inactivation of the Notch1 gene. Following infection, these mice controlled parasite growth at the site of infection and healed their lesions. The mice developed a protective Th1 immune response characterized by high levels of IFN-gamma mRNA and protein and low levels of IL-4 mRNA with no IL-4 protein in their lymph node cells. Taken together, these results indicate that Notch1 is not critically involved in CD4(+) T helper 1 differentiation and in resolution of lesions following infection with L. major. 相似文献
82.
Jean-Pierre Monthard Marcel Camps Ahmed Belfkira Michel Chatzopoulos Robert Granger Luc Jorat Grard Noyel 《Macromolecular chemistry and physics.》1985,186(7):1519-1532
The relations between structure and isothermal, dielectric properties of poly(α-acetoxystyrene)s substituted in para position by ? OCOCH3 ( 1a ), ? OCOCH2CH3 ( 1b ), ? OCOCH2CH2CH3 ( 1c ), ? OCOC6H5 ( 1d ), ? OCOCH2CH2Cl ( 1f ) and ? OCOOCH3 ( 1g ) were studied. The dielectric constants, at 105 Hz and 20 ± 2°C, were found to be: 3,79 ( 1a ), 3,36 ( 1b ), 3,18 ( 1c ), 3,51 ( 1d ), 3,36 ( 1e ), 3,65 ( 1f ) and 3,07 ( 1g ). The polymers 1a – 1g do not show any α- or β-transition. Increasing bulkiness of the para substituent gives rise to a decreasing dielectric constant due to an increase of the degree of syndiotacticity, as determined from 1H and 13C NMR spectra. 相似文献
83.
Grad Roland Leger Daniel Kaczorowski Janusz Schuster Tibor Adler Samara Aman Marya Archibald Douglas Beaulieu Marie-Claude Chmelicek John Cornelissen Evelyn Delleman Bethany Hadj-Mimoune Sonia Horvey Samantha Macaluso Steven Mintsioulis Stephen Murdoch Stuart Ng Brian Papineau Alain Rangwala Sohil Rousseau Mathieu Rudkin Teresa Schabort Inge Schultz Karen Snow Pamela Wong Eric Wu Pearson Brailovsky Carlos 《Advances in health sciences education : theory and practice》2021,26(3):771-783
Advances in Health Sciences Education - Spaced education is a learning strategy to improve knowledge acquisition and retention. To date, no robust evidence exists to support the utility of spaced... 相似文献
84.
Ben Khadhra Hajer Rose-Robert Françoise Herpe Yves Edouard Sevestre Henri Choukroun Gabriel Catherine Luc Amant Carole Saint Fabien 《International urology and nephrology》2021,53(1):59-67
International Urology and Nephrology - Biomarkers for the diagnosis and monitoring treatment response of kidney cancer are urgently needed. Neutrophil gelatinase-associated lipocalin (NGAL) is a... 相似文献
85.
Julien Guihaire Serena D'Avino Francois Stephan Martin Kloeckner Ngoc Tram To Agathe Potier Maïra Gaillard Ramzi Ramadan Jean‐Luc Taupin Jerome Le Pavec Philippe Deleuze 《Clinical transplantation》2021,35(1):e14146
Antihuman leukocyte antigen (HLA) antibodies restrict the access to cardiac allografts. Desensitization therapy is a major challenge in patients with cardiogenic shock waiting for urgent heart transplantation (HT). We retrospectively reviewed six patients (mean age of 37.5 years [16–70]) who underwent plasmapheresis (PP) under extracorporeal membrane oxygenation (ECMO) before transplant between January 2017 and September 2018. The average duration of follow‐up was 25 months [20–32]. Mean fluorescence intensity (MFI) of HLA‐specific antibodies was reported as follows: score 4 for MFI < 1000, score 6 for 1000 < MFI < 3000 and score 8 for MFI > 3000. The mean duration of ECMO support was 29 days [1–74] and 6.8 [1–29] PP sessions were performed per patient before transplant. The mean number of HLA‐specific antibodies before HT was 9.6 for score 6 [4–13] and 5.8 for score 8 [1–12]. Four patients had major complications after transplantation (2 hemorrhagic shocks, 5 infectious events). Mean MFI reduction rate was 94% [79–100] for Class I and 44.2% for Class II [0–83]. Hospital survival was 100%, and early antibody‐mediated rejection was diagnosed in one patient at 7 days after HT. Plasmapheresis under ECMO support was associated with favorable early outcomes in highly sensitized candidates for urgent heart transplantation. 相似文献
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88.
Mattias Delpont Manon Racicot Andr Durivage Lucie Fornili Jean‐Luc Guerin Jean‐Pierre Vaillancourt Mathilde C. Paul 《Transboundary and Emerging Diseases》2021,68(1):51-61
Biosecurity is crucial for infectious disease prevention, more importantly in the absence of vaccination. The need for improving the implementation of biosecurity practices was highlighted in French duck farms following the 2016–2017 H5N8 Highly Pathogenic Avian Influenza (HPAI) epidemic. Farmers have multiple reasons for not implementing biosecurity practices: external (time, money) and internal (socio‐psychological). The purpose of this study was to determine how sets of socio‐psychological factors (i.e. knowledge on biosecurity and avian influenza transmission, attitudes, personality traits, social background) affect the adoption of on‐farm biosecurity practices. Biosecurity practices and socio‐psychological determinants were assessed during 127 duck farm visits, in South West France, using both questionnaires and on‐farm observations. Factorial analysis of mixed data (FAMD) and hierarchical clustering analysis (HCA) identified three groups of farmers with different socio‐psychological profiles: the first group was characterized by minimal knowledge, negative attitudes towards biosecurity, little social pressure and a low level of conscientiousness. The second group was characterized by more extensive experience in poultry production, higher stress and social pressure. The third group was characterized by less experience in poultry production, better knowledge and positive attitudes towards biosecurity, increased self‐confidence and orientation towards action. The first group had a significantly lower adoption of biosecurity measures than the two other groups. A better understanding of the factors involved in farmers' decision‐making could improve the efficiency of interventions aiming at improving and maintaining the level of on‐farm biosecurity in the duck industry. 相似文献
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