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81.
Impairment of muscular metabolism in chronic respiratory failure. A human 31P MRS study 总被引:1,自引:0,他引:1
J F Payen B Wuyam H Reutenauer D Laurent P Levy J F Le Bas A L Benabid 《NMR in biomedicine》1991,4(1):41-45
The calf muscle metabolism of 7 patients with stable chronic respiratory failure (PaO2 below 65 Torr) was studied using 31P NMR spectroscopy. NMR spectra were acquired at rest, during the course of 360 pedal movements at 20, 35 and 50% of the maximal voluntary contraction (MVC) and during recovery. Eight normal aged-matched subjects served as a control group. In resting muscle, no significant differences were observed between both groups as regards intracellular pH, inorganic phosphate/phosphocreatine (Pi/PCr) and beta-ATP/PCr + Pi + phosphomonoester (PME) ratios. Although effective power outputs were similar for both groups at each work level, patients exhibited a higher Pi/PCr ratio than healthy controls (3.19 +/- 1.01 vs 0.49 +/- 0.05 at 50% MVC; p less than 0.01) and a lower pHi (6.65 +/- 0.11 vs 7.06 +/- 0.02 at 50% MVC; p less than 0.01). Moreover, PCr resynthesis during recovery was slower in patients than in control subjects (t1/2 PCr = 1.26 +/- 0.30 vs 0.47 +/- 0.05 min; p = 0.01). These results suggest impairment of aerobic capacity in a non-ventilatory working muscle, probably due to hypoxemia in patients with chronic respiratory failure. 相似文献
82.
Behazine Sadat-Sowti Patrice Debr Lucile Mollet Laurent Quint Fabienne Hadida Vronique Leblond Georges Bismuth Brigitte Autran 《European journal of immunology》1994,24(11):2882-2888
An inhibitor of the cytotoxic functions (ICF) mediated by human immunodeficiency virus (HIV)- or HLA-specific cytotoxic T lymphocytes, natural killer and lymphokine-activated killer (LAK) cells is secreted by CD8+CD57? T lymphocytes, a subset expanded during infection with HIV and after bone marrow transplantation. We previously showed an apparent molecular mass of 20–30 kDa for this soluble glycosylated concanavalin A-binding inhibitor which is distinct from known cytokines. Here, we report a characterization of the mechanism of action of this CD8+CD57+ ICF. We show that the ICF-induced inhibition of LAK cell cytolytic activity is transient, with a spontaneous recovery of cytolytic potential after 18 h. When testing interactions of ICF with a large set of cytokines we found that the ICF-mediated inhibition of cytotoxic functions is antagonized by two cytokines: recombinant interleukin (rIL)-4 and recombinant interferon (rIFN)-γ. Finally, we show that ICF acts at the level of cytolytic effector cells, where it induces a significant increase of cyclic AMP (cAMP) level. In contrast, no modification of either cell surface antigen expression or of target/effector cell conjugate formation could be evidenced. Addition of rIL-4 and rIFN-γ reverses such an increase of cAMP levels and in parallel restores the cytolytic activity. Altogether, these data demonstrate that the glycoprotein ICF produced by CD8+CD57+ cells (1) inhibits cell-mediated cytotoxicity by sensitizing cytolytic effector cells to the cAMP pathway, and (2) is part of a cytokine network controlling cell-mediated cytotoxic functions. 相似文献
83.
Three cases of nephroblastoma presented "egg-shell" peripheral calcifications of pseudocystic appearance of radiology. These peripheral lesions are compared with the more commonly reported central calcifications. Their pathology is unknown and they lack prognostic significance of any importance. As for all nephroblastomas the diagnosis is based on straight abdomen images, intravenous urography, ultrasound and computed tomography. Differential diagnosis is basically from renal adenocarcinoma in children, the latter often exhibiting similar calcifications, the distinction between the two types of tumor depending on age of onset. These calcified lesions are non-specific findings and various diagnoses are discussed. 相似文献
84.
Barriers and Facilitators to Participation in Health Screening: an Umbrella Review Across Conditions
Le Bonniec Alice Sun Sophie Andrin Amandine Dima Alexandra L. Letrilliart Laurent 《Prevention science》2022,23(7):1115-1142
Prevention Science - Screening is an essential prevention practice for a number of health conditions. However, screening coverage remains generally low. Studies that investigate determinants of... 相似文献
85.
Pauline Vetter Arnaud G. LHuillier Maria F. Montalbano Fiona Pigny Isabella Eckerle Giulia Torriani Sylvia Rothenberger Florian Laubscher Samuel Cordey Laurent Kaiser Manuel Schibler 《Emerging infectious diseases》2021,27(2):658
We report 3 cases of Puumala virus infection in a family in Switzerland in January 2019. Clinical manifestations of the infection ranged from mild influenza-like illness to fatal disease. This cluster illustrates the wide range of clinical manifestations of Old World hantavirus infections and the challenge of diagnosing travel-related hemorrhagic fevers. 相似文献
86.
87.
Sybille Rousseau Matthieu Peycelon Céline Grosos Valeska Bidault Anna Poupalou Garance Martin Éric Dobremez Luke Harper Claire Raquillet Alexis Arnaud Emmanuel Sapin Aurélien Scalabre Philippe Buisson Guillaume Levard Isabelle Pommepuy Maguelonne Pons Laurent Fourcade Quentin Ballouhey 《Journal of pediatric surgery》2021,56(2):332-336
IntroductionFibroepithelial polyps (FEP) of the lower urinary tract are relatively common in adults but rare in children, with fewer than 250 cases reported in the literature to date.ObjectiveThe aim of this study was to address the experience of FEP management in children.Study designA retrospective multicenter review was undertaken in children with defined FEP of the lower urinary tract managed between 2008 and 2018. The data at 18 pediatric surgery centers were collected. Their demographic, radiological, surgical, and pathological information were reviewed.ResultsA total of 33 children (26 boys; 7 girls) were treated for FEP of the lower urinary tract at 13 centers. The most common presentation was urinary outflow as hematuria (41%), acute urinary retention (25%), dysuria (19%), or urinary infections (28%). A prenatal diagnosis was made for three patients with hydronephrosis. Almost all of the children (94%) underwent ultrasound imaging of the urinary tract as the first diagnostic examination, 23 (70%) of them also either had an MRI (15%), cystourethrography (25%), computerized tomography (6%), or cystoscopy (45%). Two of these children (6%) had a biopsy prior to the surgery. The median preoperative delay was 7.52 (range: 1–48) months. Most of the patients were treated endoscopically, although four (12.1%) had open surgery and two (6.1%) had an additional incision for specimen extraction. The median hospital stay was 1.5 (range: 1–10) days. There were no recurrences and no complications after a median follow-up of 13 (range: 1–34) months.DiscussionThe main limitation of our study is the retrospective design, although it is the largest one for this pathology.ConclusionThis series supports sonography as the most suitable diagnosis tool before endoscopy to confirm the diagnosis and to perform the resection for most FEP in children. This report confirms the recognized benign nature in the absence of recurrences.Level of EvidenceLevel V. 相似文献
88.
类风湿关节炎(RA)在中医学中属于“痹病”范畴,是临床中常见的难治性疾病,且呈年轻化趋势,迁延难愈。目前现代医学对RA的发病病因及机制尚不完全清楚。《素问·痹论》提出风寒湿三邪致痹,还有学者提出痰瘀致痹、肝肾亏虚等观点。李彦民主任医师根据多年临床经验提出RA的病机关键是络脉痹阻,其病机特点是虚实夹杂,临床辨证分为寒湿阻络型、湿热蕴结型、痰瘀互结型、气血两虚型、肝肾亏虚型等五型。分别采用祛邪通络和补虚通络等不同治则,辨证施法。李老师善用川乌、鸡血藤以及乌梢蛇等药以通络止痛,并主张辨证用药,内外兼治,多取良效。临床采用经验方仙龙汤,配合外用舒筋活络洗剂,且取得理想疗效。 相似文献
89.