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排序方式: 共有1319条查询结果,搜索用时 15 毫秒
31.
Surana SP Doddamani S Swaminathan A Mehta MB Zeltser R Vatsia SK Makaryus AN 《Echocardiography (Mount Kisco, N.Y.)》2012,29(4):E102-E104
Approximately 1% of adults who undergo cardiac catheterization have coronary anomalies. Patients may present with chest pain, arrhythmias, presyncope, and sometimes sudden cardiac death. Multidetector computed tomography (MDCT) is an excellent tool for identifying coronary artery anomalies and defining their course and relationship to the great vessels and surrounding structures; its value is incremental to conventional angiography. We present a rare case of a coronary anomaly involving three separate ostia at the right sinus of Valsalva for the left and right coronary vessels. 相似文献
32.
Carvalho VC Oliveira PR Dal-Paz K Paula AP Félix Cda S Lima AL 《The Brazilian journal of infectious diseases》2012,16(1):63-67
IntroductionDespite the growing interest in the study of Gram-negative bacilli (GNB) infections, very little information on osteomyelitis caused by GNB is available in the medical literature.Objectives and methods: To assess clinical and microbiological features of 101 cases of osteomyelitis caused by GNB alone, between January 2007 and January 2009, in a reference center for the treatment of high complexity traumas in the city of São Paulo.ResultsMost patients were men (63%), with median age of 42 years, affected by chronic osteomyelitis (43%) or acute osteomyelitis associated to open fractures (32%), the majority on the lower limbs (71%). The patients were treated with antibiotics as inpatients for 40 days (median) and for 99 days (median) in outpatient settings. After 6 months follow-up, the clinical remission rate was around 60%, relapse 19%, amputation 7%, and death 5%. Nine percent of cases were lost to follow-up. A total of 121 GNB was isolated from 101 clinical samples. The most frequently isolated pathogens were Enterobacter sp. (25%), Acinetobacter baumannii (21%) e Pseudomonas aeruginosa (20%). Susceptibility to carbapenems was about 100% for Enterobacter sp., 75% for Pseudomonas aeruginosa and 60% for Acinetobacter baumannii.ConclusionOsteomyelitis caused by GNB remains a serious therapeutic challenge, especially when associated to nonfermenting bacteria. We emphasize the need to consider these agents in diagnosed cases of osteomyelitis, so that an ideal antimicrobial treatment can be administered since the very beginning of the therapy. 相似文献
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Quintero-Hernández V Juárez-González VR Ortíz-León M Sánchez R Possani LD Becerril B 《Molecular immunology》2007,44(6):1307-1315
The antigen-binding fragment (Fab) has been considered a more functionally stable version of recombinant antibodies than single chain antibody fragments (scFvs), however this intuitive consideration has not been sufficiently proven in vivo. This communication shows that three out of four specific scFvs against a scorpion toxin, with different affinities and stabilities, become neutralizing in vivo when expressed as Fabs, despite the fact that they are not neutralizing in the scFv format. A scFv fragment previously obtained from a neutralizing mouse antibody (BCF2) was used to produce three derived scFvs by directed evolution. Only one of them was neutralizing, however when expressed as Fab, all of them became neutralizing fragments in vivo. The initial scFvBCF2 (earlier used for directed evolution) was not neutralizing in the scFv format. After expressing it as Fab did not become a neutralizing fragment, but did reduce the intoxication symptoms of experimental mice. The stability of the four Fabs derived from their respective scFvs was improved when tested in the presence of guanidinium chloride. The in vitro stability of the Fab format has been shown earlier, but the physiological consequences of this stability are shown in this communication. The present results indicate that improved functional stability conferred by the Fab format can replace additional maturation steps, when the affinity and stability are close to the minimum necessary to be neutralizing. 相似文献
35.
Saúl Reveles‐Flix Rosalba Carren‐Npoles Susana Mendoza‐Elvira Víctor Quintero‐Ramírez Juvencio García‐Snchez Rebeca Martínez‐Bautista Manuel Saavedra‐Montaez Juan Joel Mosqueda Gualito Jos Ivan Snchez‐Betancourt 《Transboundary and Emerging Diseases》2020,67(2):1035-1041
As an emerging disease, the porcine epidemic diarrhoea virus has caused substantial economic losses to the pork industry in Mexico, leading to piglet mortality rates of up to 100%. For detection, sequencing and genetic characterization of the virus, 68 samples of one‐week‐old piglets from pork farms in 17 states of Mexico were analysed. In total, 53 samples were positive by real‐time RT‐PCR, confirming the presence of the virus in 15 states. Twenty‐eight samples from 10 states were amplified by endpoint RT‐PCR, and 20 sequences of the spike gene were obtained. A phylogenetic analysis based on the spike gene demonstrated that all Mexican strains are in Group II and are classified as non‐Indel‐S emerging variants. Three strains showed amino acid insertions: PEDv/MEX/GTO/LI‐DMZC15/2015 and PEDv/MEX/QRO/LI‐DMZC45/2016 showed one amino acid insertion (424Y425 and 447D448, respectively), and PEDv/MEX/QRO/LI‐DMZC49/2019 showed one and two amino acid insertions (422C423 and 537SQ538), with the second insertion in the COE region. These results provide evidence of the prevalence of emerging, non‐Indel‐S strains of the virus are currently circulating in Mexico during 2016–2018, when three of which have amino acid insertions: PEDv/MEX/GTO/IN‐DMZC15/2015 and PEDv/MEX/QRO/IN‐DMZC45/2016 have one amino acid insertion each (424Y425 and 447D448, respectively), and PEDv/MEX/QRO/IN‐DMZC49/2019 has one (422C423) and two amino acid insertions (537SQ538), the latter being in the COE region, which could generate new antigenic variants. 相似文献
36.
Sara Artusi Emanuela Ruggiero Matteo Nadai Beatrice Tosoni Rosalba Perrone Annalisa Ferino Irene Zanin Luigi Xodo Louis Flamand Sara N. Richter 《Viruses》2021,13(2)
The herpes simplex virus 1 (HSV-1) genome is extremely rich in guanine tracts that fold into G-quadruplexes (G4s), nucleic acid secondary structures implicated in key biological functions. Viral G4s were visualized in HSV-1 infected cells, with massive virus cycle-dependent G4-formation peaking during viral DNA replication. Small molecules that specifically interact with G4s have been shown to inhibit HSV-1 DNA replication. We here investigated the antiviral activity of TMPyP4, a porphyrin known to interact with G4s. The analogue TMPyP2, with lower G4 affinity, was used as control. We showed by biophysical analysis that TMPyP4 interacts with HSV-1 G4s, and inhibits polymerase progression in vitro; in infected cells, it displayed good antiviral activity which, however, was independent of inhibition of virus DNA replication or entry. At low TMPyP4 concentration, the virus released by the cells was almost null, while inside the cell virus amounts were at control levels. TEM analysis showed that virus particles were trapped inside cytoplasmatic vesicles, which could not be ascribed to autophagy, as proven by RT-qPCR, western blot, and immunofluorescence analysis. Our data indicate a unique mechanism of action of TMPyP4 against HSV-1, and suggest the unprecedented involvement of currently unknown G4s in viral or antiviral cellular defense pathways. 相似文献
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38.
A new member of the tumor necrosis factor/nerve growth factor receptor family inhibits T cell receptor-induced apoptosis 下载免费PDF全文
Giuseppe Nocentini Linda Giunchi Simona Ronchetti Ludovic Tibor Krausz Andrea Bartoli Rosalba Moraca Graziella Migliorati Carlo Riccardi 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(12):6216-6221
By comparing untreated and dexamethasone-treated murine T cell hybridoma (3DO) cells by the differential display technique, we have cloned a new gene, GITR (glucocorticoid-induced tumor necrosis factor receptor family-related gene) encoding a new member of the tumor necrosis factor/nerve growth factor receptor family. GITR is a 228-amino acids type I transmembrane protein characterized by three cysteine pseudorepeats in the extracellular domain and similar to CD27 and 4-1BB in the intracellular domain. GITR resulted to be expressed in normal T lymphocytes from thymus, spleen, and lymph nodes, although no expression was detected in other nonlymphoid tissues, including brain, kidney, and liver. Furthermore, GITR expression was induced in T lymphocytes upon activation by anti-CD3 mAb, Con A, or phorbol 12-myristate 13-acetate plus Ca-ionophore treatment. The constitutive expression of a transfected GITR gene induced resistance to anti-CD3 mAb-induced apoptosis, whereas antisense GITR mRNA expression lead to increased sensitivity. The protection toward T cell receptor-induced apoptosis was specific, because other apoptotic signals (Fas triggering, dexamethasone treatment, or UV irradiation) were not modulated by GITR transfection. Thus, GITR is a new member of tumor necrosis factor/nerve growth factor receptor family involved in the regulation of T cell receptor-mediated cell death. 相似文献
39.
Ponzetto M Maero B Maina P Rosato R Ciccone G Merletti F Rubenstein LZ Fabris F 《The journals of gerontology. Series A, Biological sciences and medical sciences》2003,58(11):1049-1054
BACKGROUND: Prognostic information collected at hospital admission may be useful in defining care objectives and in deciding on therapy for older people. The aim of our study was to identify admission risk factors for in-hospital and postdischarge mortality. METHODS: The study included 987 patients aged 70 years and older admitted to the geriatric ward of San Giovanni Battista Hospital in Torino during 1995 and 1996. Demographic, clinical, and functional variables were collected on admission to hospital and examined as potential risk factors for mortality during hospitalization and at 5 years of follow-up. RESULTS: During their hospital stay, 147 patients (14.9%) died. Risk factors independently associated with in-hospital mortality included functional impairment (Activities of Daily Living [ADL]) (OR [odds ratio] 1.73, CI [confidence interval] 95% 1.02-2.95), dependence related to medical conditions (OR 2.18, CI 95% 1.39-3.42), cerebrovascular disease (OR 3.23, CI 95% 1.64-6.37), cancer (OR 4.52, CI 95% 1.99-10.24), albumin 3.0-3.4 g/dl (OR 4.51, CI 95% 2.76-7.35), albumin <3.0 g/dl (OR 6.83, CI 95% 3.59-13.0), creatinine 1.5-3 mg/dl (OR 2.23, CI 95% 1.36-3.65), creatinine >3 mg/dl (OR 2.55, CI 95% 1.10-5.93), and fibrinogen >/=452 mg/dl (OR 1.91, CI 95% 1.26-2.89). During the 5-year follow-up, 553 patients (67.7%) died. Variables independently associated with mortality in multivariate analysis were age 75-84 years (HR [hazard ratio] 1.40, CI 95% 1.10-1.78), >/=85 years (HR 2.08, CI 95% 1.59-2.72), male sex (HR 1.50, CI 95% 1.24-1.81), ADL dependency (HR 1.24, CI 95% 1.01-1.52), >/=5 errors on Short Portable Mental Status Questionnaire (HR 1.34, CI 95% 1.10-1.63), dependence on Dependence Medical Index (HR 1.36, CI 95% 1.10-1.67), presence of cancer (HR 2.58, CI 95% 1.80-3.71), hemoglobin =11 g/dl (HR 1.46, CI 95% 1.17-1.81), and Charlson's Index >/=2 (HR 1.49, CI 95% 1.14-1.95). CONCLUSIONS: A complete functional and clinical evaluation at hospital admission permits identification of patients at higher risk of early and long-term mortality. 相似文献
40.
Ester Orlandi MD Stefano Cavalieri MD Roberta Granata MD Piero Nicolai MD Paolo Castelnuovo MD Cesare Piazza MD Alberto Schreiber MD Mario Turri-Zanoni MD Pasquale Quattrone MD Rosalba Miceli MD Gabriele Infante PhD Fausto Sessa MD Carla Facco MD Giuseppina Calareso MD Nicola Alessandro Iacovelli MD Davide Mattavelli MD Alberto Paderno MD Carlo Resteghini MD Laura Deborah Locati MD Lisa Licitra MD Paolo Bossi MD 《The Laryngoscope》2020,130(4):857-865