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排序方式: 共有1378条查询结果,搜索用时 5 毫秒
31.
Roberto Gasparini Maurizio Comanducci Daniela Amicizia Filippo Ansaldi Paola Canepa Andrea Orsi Giancarlo Icardi Emanuela Rizzitelli Gabriella De Angelis Stefania Bambini Monica Moschioni Sara Comandi Isabella Simmini Giueseppe Boccadifuoco Brunella Brunelli Marzia Monica Giuliani Mariagrazia Pizza Donatella Panatto 《Journal of clinical microbiology》2014,52(6):1901-1910
Neisseria meningitidis is an obligate human commensal that commonly colonizes the oropharyngeal mucosa. Carriage is age dependent and very common in young adults. The relationships between carriage and invasive disease are not completely understood. In this work, we performed a longitudinal carrier study in adolescents and young adults (173 subjects). Overall, 32 subjects (18.5%) had results that were positive for meningococcal carriage in at least one visit (average monthly carriage rate, 12.1%). Only five subjects tested positive at all four visits. All meningococcal isolates were characterized by molecular and serological techniques. Multilocus sequence typing, PorA typing, and sequencing of the 4CMenB vaccine antigens were used to assess strain diversity. The majority of positive subjects were colonized by capsule null (34.4%) and capsular group B strains (28.1%), accounting for 23.5% and 29.4% of the total number of isolates, respectively. The fHbp and nhba genes were present in all isolates, while the nadA gene was present in 5% of the isolates. The genetic variability of the 4CMenB vaccine antigens in this collection was relatively high compared with that of other disease-causing strain panels. Indications about the persistence of the carriage state were limited to the time span of the study. All strains isolated from the same subject were identical or cumulated minor changes over time. The expression levels and antigenicities of the 4CMenB vaccine antigens in each strain were analyzed by the meningococcal antigen typing system (MATS), which revealed that expression can change over time in the same individual. Future analysis of antigen variability and expression in carrier strains after the introduction of the MenB vaccine will allow for a definition of its impact on nasopharyngeal/oropharyngeal carriage. 相似文献
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Janaina Brollo Maximiliano Cassilha Kneubil Edoardo Botteri Nicole Rotmensz Bruno Achutti Duso Luca Fumagalli Marzia Adelia Locatelli Carmen Criscitiello Visnu Lohsiriwat Aron Goldhirsch Maria Cristina Leonardi Roberto Orecchia Giuseppe Curigliano 《Breast (Edinburgh, Scotland)》2013,22(5):856-862
Literature shows that HER2/neu positive breast cancer cells are more sensitive to radiation-induced apoptosis by targeting the epidermal growth factor receptor family tyrosine kinase. We selected 466 patients with pT1-2 HER2/neu positive tumors who received adjuvant trastuzumab for primary invasive breast cancer. Patients were divided into three groups [Quadrantectomy followed by conventional radiotherapy vs Quadrantectomy followed by Intra-operative radiotherapy with electrons vs Mastectomy without radiotherapy]. After a median follow-up of 52 months, the 5-year cumulative incidence of locoregional recurrence (LRR) was 1.9%, 11.5% and 5.0% respectively (p < 0.01). At the multivariate analysis, extensive perivascular invasion, Luminal B HER2/Progesterone Receptor (PgR) negative status and Quadrantectomy followed by Intra-operative radiotherapy with electrons have significantly increased the risk of LRR. Our results suggest that HER2/neu positive breast cancer might have better outcomes when treated simultaneously with external radiotherapy and trastuzumab. Moreover, we underline the importance of PgR and further new stratification of risk among luminal subtypes. 相似文献
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Luigi Angelo Vaira Claire Hopkins Giovanni Salzano Marzia Petrocelli Andrea Melis Marco Cucurullo Mario Ferrari Laura Gagliardini Carlotta Pipolo Giovanna Deiana Vito Fiore Andrea De Vito Nicola Turra Sara Canu Angelantonio Maglio Antonello Serra Francesco Bussu Giordano Madeddu Sergio Babudieri Alessandro Giuseppe Fois Pietro Pirina Francesco A. Salzano Pierluigi De Riu Federico Biglioli Giacomo De Riu 《Head & neck》2020,42(7):1560-1569
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HIF-2alpha regulates murine hematopoietic development in an erythropoietin-dependent manner 总被引:2,自引:0,他引:2
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Scortegagna M Ding K Zhang Q Oktay Y Bennett MJ Bennett M Shelton JM Richardson JA Moe O Garcia JA 《Blood》2005,105(8):3133-3140
Erythropoiesis in the adult mammal depends critically on erythropoietin, an inducible cytokine with pluripotent effects. Erythropoietin gene expression increases under conditions associated with lowered oxygen content such as anemia and hypoxia. HIF-1alpha, the founding member of the hypoxia-inducible factor (HIF) alpha class, was identified by its ability to bind and activate the hypoxia-responsive enhancer in the erythropoietin regulatory region in vitro. The existence of multiple HIF alpha members raises the question of which HIF alpha member or members regulates erythropoietin expression in vivo. We previously reported that mice lacking wild-type HIF-2alpha, encoded by the EPAS1 gene, exhibit pancytopenia. In this study, we have characterized the etiology of this hematopoietic phenotype. Molecular studies of EPAS1-null kidneys reveal dramatically decreased erythropoietin gene expression. EPAS1-null as well as heterozygous mice have impaired renal erythropoietin induction in response to hypoxia. Treatment of EPAS1-null mice with exogenous erythropoietin reverses the hematopoietic and other defects. We propose that HIF-2alpha is an essential regulator of murine erythropoietin production. Impairments in HIF signaling, involving either HIF-1alpha or HIF-2alpha, may play a prominent role in conditions involving altered hematopoietic or erythropoietin homeostasis. 相似文献
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Simona Puzelli Giada Rossini Marzia Facchini Gabriele Vaccari Livia Di Trani Angela Di Martino Paolo Gaibani Caterina Vocale Giovanni Cattoli Michael Bennett John W. McCauley Giovanni Rezza Maria Luisa Moro Roberto Rangoni Alba Carola Finarelli Maria Paola Landini Maria Rita Castrucci Isabella Donatelli the Influenza Task Force 《Emerging infectious diseases》2014,20(10):1745-1749
During an influenza A(H7N7) virus outbreak among poultry in Italy during August–September 2013, infection with a highly pathogenic A(H7N7) avian influenza virus was diagnosed for 3 poultry workers with conjunctivitis. Genetic analyses revealed that the viruses from the humans were closely related to those from chickens on affected farms. 相似文献
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