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51.
Forced oscillation impedance (Zrs) measurements are frequently corrupted by noisy data in children. Our aim was to improve the reliability of respiratory resistance (Rrs) and routine identification of its flow (V') and volume (V) dependence during tidal breathing, according to Rrs = K1 + K2 x /V'/ + K3 x V. Zrs was measured at 12 Hz, using a head generator in 23 children aged 4-13 years undergoing methacholine (Mch) challenge. Rrs, K1, K2, K3, and residual mean square error (RMSD), as well as reproducibility of the parameters, were obtained. Calculations were performed separately in inspiration and expiration on the raw data, and after eliminating values lying outside confidence intervals ranging from 99% (F3SD) to 95% (F2SD) of the mean Zrs. Filtering decreased RMSD and Rrs, F3SD improved reproducibility of Rrs in expiration compared to raw data. F2SD increased K1 and decreased the amplitude of K2 and K3 before and after Mch compared to F3SD. Rrs and K2 were significantly larger and K3 significantly more negative in expiration than in inspiration at all levels of filtering, probably because of the upper airways. F3SD appeared efficient in eliminating aberrant data, while allowing the identification of physiological variations of Rrs. 相似文献
52.
Cyril Fisher 《Ultrastructural pathology》2013,37(5-6):291-305
A subset of low-grade fibrosarcomas is composed of CD34-positive spindle cells. These include dermatofibrosarcoma, its morphologic variants, and its associated fibrosarcoma, solitary fibrous tumor, hemangiopericytoma and their malignant counterparts, and some cases of myxoinflammatory fibroblastic sarcoma. Dermatofibrosarcoma and related lesions are characterized by a t(17;22)(q22;q13) rearrangement resulting in fusion of the genes COL1A (17q21-22) and PDGFB1 (22q13). Solitary fibrous tumor displays varying cellularity and fibrosis and a peripheral hemangiopericytomatous pattern; most tumors formerly called hemangiopericytoma are now subsumed into the category of solitary fibrous tumor, although a few strictly defined examples are recognized; however, these are probably not composed of pericytes. Myofibroblastic malignancies are best identified by electron microscopy, with which varying degrees of differentiation, including the presence of fibronexus junctions, can be identified. Low-grade sarcomas showing myofibroblastic differentiation include myofibrosarcomas and inflammatory myofibroblastic tumors. Myofibrosarcomas are spindle cell neoplasms that occur in children or adults in the head and neck, trunk, and extremities as infiltrative neoplasms and that display a fascicular or fasciitis-like pattern with focal nuclear atypia and variable expression of myoid antigens. These sarcomas are prone to recurrence and a small number metastasize. Inflammatory myofibroblastic tumor (synonymous with inflammatory fibrosarcoma) is a neoplasm arising predominantly in childhood, and frequently in intraabdominal locations. It has spindle cells in fascicular, fasciitis-like and sclerosing patterns, with heavy chronic inflammation including abundant plasma cells. Many IMT have clonal chromosomal abnormalities involving 2p22-24, and fusion of the ALK gene with tropomyosin 3 (TPM3-ALK) or tropomyosin 4 (TPM4-ALK) is found in a subset. 相似文献
53.
Ter Schiphorst Adrien Gaillard Nicolas Dargazanli Cyril Mourand Isabelle Corti Lucas Charif Mahmoud Ayrignac Xavier Lippi Anaïs Bouly Stéphane Thibault Lalu Sablot Denis Blanchet-Fourcade Genevieve Landragin Nicolas Costalat Vincent Duflos Claire Arquizan Caroline 《Journal of neurology》2021,268(1):346-355
Journal of Neurology - Symptomatic isolated carotid artery occlusions (ICAO) can lead to disability, recurrent stroke, and mortality, but natural history and best therapeutic management remain... 相似文献
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55.
Christoph Käcker Alexander Marx Katharina Mössinger Frederike Svehla Ulrike Schneider Pancras Cornelis Wilhelmus Hogendoorn Ole Steen Nielsen Stefan Küffer Christian Sauer Cyril Fisher Christian Hallermann Jörg Thomas Hartmann Jean‐Yves Blay Gunhild Mechtersheimer Peter Hohenberger Philipp Ströbel 《Genes, chromosomes & cancer》2013,52(1):93-98
Irradiation is a major causative factor among the small subgroup of sarcomas with a known etiology. The prognosis of radiation‐induced sarcomas (RIS) is significantly worse than that of their spontaneous counterparts. The most frequent histological subtypes include undifferentiated pleomorphic sarcomas, angiosarcomas, and leiomyosarcomas. A high frequency of MYC amplifications in radiation‐induced angiosarcomas, but not in primary angiosarcomas, has recently been described. To investigate whether MYC amplifications are also frequent in RIS other than angiosarcomas, we analyzed the MYC amplification status of 83 RIS and 192 sporadic sarcomas by fluorescence in situ hybridization. We found significantly higher numbers of MYC amplifications in RIS than in sporadic sarcomas (P < 0.0001), especially in angiosarcomas, undifferentiated pleomorphic sarcomas, and leiomyosarcomas. Angiosarcomas were special in that MYC amplifications were particularly frequent and always high level, while other RIS showed low‐level amplifications. We conclude that MYC amplifications are a frequent feature of RIS as a group and may contribute to the biology of these tumors. © 2012 Wiley Periodicals, Inc. 相似文献
56.
Cyril Perez Gary Finelle Cauris Couvrechel 《Australian endodontic journal : the journal of the Australian Society of Endodontology Inc》2020,46(1):107-114
This paper demonstrates the usefulness of endodontic guides for the removal of fibre posts. A 36‐year‐old man consulted for retreatment of a maxillary first molar presenting a periapical pathology. This tooth revealed a composite reconstruction together with a glass‐fibre post in the palatal root canal. To assist removal, use of an endodontic 3D‐printed guide was indicated. A cone beam computed tomography examination and an optical impression were made to produce a tooth‐supported guide by means of implant planning software (Blue Sky Plan, Blue Sky Bio®). The software enabled definition of a drilling pathway, which was transferred clinically using a resin template together with a sleeve and a 0.75‐mm drill. The drill was guided as far as the gutta‐percha situated in the apical third, limiting any risk of impairment or perforation. 相似文献
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59.
Cyril Touboul Marcos Ballester Gil Dubernard Sonia Zilberman Anne Thomin Emile Daraï 《Surgical endoscopy》2015,29(7):1879-1887
60.
Ifeoma Nkiruka Menakaya Olabisi Hajarat Oderinu Ilemobade Cyril Adegbulugbe Olufemi Peter Shaba 《Saudi Dental Journal》2015,27(4):187-193