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排序方式: 共有2855条查询结果,搜索用时 31 毫秒
91.
92.
Pascale Bémer Chloé Plouzeau Didier Tande Julie Léger Bruno Giraudeau Anne Sophie Valentin Anne Jolivet-Gougeon Pascal Vincent Stéphane Corvec Sophie Gibaud Marie Emmanuelle Juvin Genevieve Héry-Arnaud Carole Lemarié Marie Kempf Laurent Bret Roland Quentin Carine Coffre Gonzague de Pinieux Louis Bernard Christophe Burucoa 《Journal of clinical microbiology》2014,52(10):3583-3589
There is no standard method for the diagnosis of prosthetic joint infection (PJI). The contribution of 16S rRNA gene PCR sequencing on a routine basis remains to be defined. We performed a prospective multicenter study to assess the contributions of 16S rRNA gene assays in PJI diagnosis. Over a 2-year period, all patients suspected to have PJIs and a few uninfected patients undergoing primary arthroplasty (control group) were included. Five perioperative samples per patient were collected for culture and 16S rRNA gene PCR sequencing and one for histological examination. Three multicenter quality control assays were performed with both DNA extracts and crushed samples. The diagnosis of PJI was based on clinical, bacteriological, and histological criteria, according to Infectious Diseases Society of America guidelines. A molecular diagnosis was modeled on the bacteriological criterion (≥1 positive sample for strict pathogens and ≥2 for commensal skin flora). Molecular data were analyzed according to the diagnosis of PJI. Between December 2010 and March 2012, 264 suspected cases of PJI and 35 control cases were included. PJI was confirmed in 215/264 suspected cases, 192 (89%) with a bacteriological criterion. The PJIs were monomicrobial (163 cases [85%]; staphylococci, n = 108; streptococci, n = 22; Gram-negative bacilli, n = 16; anaerobes, n = 13; others, n = 4) or polymicrobial (29 cases [15%]). The molecular diagnosis was positive in 151/215 confirmed cases of PJI (143 cases with bacteriological PJI documentation and 8 treated cases without bacteriological documentation) and in 2/49 cases without confirmed PJI (sensitivity, 73.3%; specificity, 95.5%). The 16S rRNA gene PCR assay showed a lack of sensitivity in the diagnosis of PJI on a multicenter routine basis. 相似文献
93.
Katrice M. Karanfilian MD Monica N. Valentin MD Rajendra Kapila MD Chinmoy Bhate MD Mahnaz Fatahzadeh DMD MSD FRCP Edin Giuseppe Micali MD FRCP Edin Robert A. Schwartz MD MPH DSc FRCP 《International journal of dermatology》2020,59(10):1185-1190
Cervicofacial actinomycosis is an uncommon, chronic, suppurative, and granulomatous bacterial infection. It is often of dental origin and tends to mimic other dental infections, granulomatous disorders, and cancers. The initial diagnostic workup, predicated upon imaging and tissue biopsies, is frequently nonspecific. A definitive diagnosis is usually rendered only after surgical excision and histologic examination of the cervicofacial mass. We propose a classification of three stages: localized infection without sinus involvement, localized infection with sinus involvement, and disseminated infection, to facilitate recognition, diagnosis, and early aggressive treatment. Untreated infection may be life-threatening. Therapy may require long-term antibiotics; however, many cases may also necessitate complete surgical excision. 相似文献
94.
95.
tefan-Andrei Irimiciuc Sergii Chertopalov Michal Novotný Valentin Craciun Jan Lancok Maricel Agop 《Materials》2022,15(8)
The recent advancements in pulsed laser deposition (PLD) control via plasma diagnostics techniques have been positive and raised questions on the limitation of some techniques, such as the Langmuir probe (LP). The particularities of laser-produced plasma can lead to incorrect interpretation of collected electrical signal. In this paper, we explored the limitations of LP as a technique for in situ PLD control by performing investigations on several metallic plasmas, expanding in various Ar atmosphere conditions. Sub-microsecond modulation was seen in the reconstructed IV characteristics attributed to non-equilibrium dynamics of the ejected charges. A perturbative regime was recorded for Ar pressures higher than 2 Pa, where ionic bursts were observed in the electron saturation region. This perturbation was identified as a plasma fireball. A non-linear multifractal model was developed here to explore these new regimes of the LP. The strange attractors characterizing each fireball were reconstructed, and their evolution with the Ar pressure is discussed. Both short- and long-time non-linear behavior were correlated via probe bias, and the pressure effect on the strange attractor’s defining the fireball-like behavior was investigated. A good correlation was noticed between the simulated data and experimental findings. 相似文献
96.
Han S. Lim Mélèze Hocini Remi Dubois Arnaud Denis Nicolas Derval Stephan Zellerhoff Seigo Yamashita Benjamin Berte Saagar Mahida Yuki Komatsu Matthew Daly Laurence Jesel Carole Pomier Valentin Meillet Sana Amraoui Ashok J. Shah Hubert Cochet Frédéric Sacher Michel Haïssaguerre 《Journal of the American College of Cardiology》2017,69(10):1257-1269
Background
The underlying mechanisms sustaining human persistent atrial fibrillation (PsAF) is poorly understood.Objectives
This study sought to investigate the complexity and distribution of AF drivers in PsAF of varying durations.Methods
Of 135 consecutive patients with PsAF, 105 patients referred for de novo ablation of PsAF were prospectively recruited. Patients were divided into 3 groups according to AF duration: PsAF presenting in sinus rhythm (AF induced), PsAF <12 months, and PsAF >12 months. Patients wore a 252-electrode vest for body surface mapping. Localized drivers (re-entrant or focal) were identified using phase-mapping algorithms.Results
In this patient cohort, the most prominent re-entrant driver regions included the pulmonary vein (PV) regions and inferoposterior left atrial wall. Focal drivers were observed in 1 or both PV regions in 75% of patients. Comparing between the 3 groups, with longer AF duration AF complexity increased, reflected by increased number of re-entrant rotations (p < 0.05), number of re-entrant rotations and focal events (p < 0.05), and number of regions harboring re-entrant (p < 0.01) and focal (p < 0.05) drivers. With increased AF duration, a higher proportion of patients had multiple extra-PV driver regions, specifically in the inferoposterior left atrium (p < 0.01), superior right atrium (p < 0.05), and inferior right atrium (p < 0.05). Procedural AF termination was achieved in 70% of patients, but decreased with longer AF duration.Conclusions
The complexity of AF drivers increases with prolonged AF duration. Re-entrant and focal drivers are predominantly located in the PV antral and adjacent regions. However, with longer AF duration, multiple drivers are distributed at extra-PV sites. AF termination rate declines as patients progress to longstanding PsAF, underscoring the importance of early intervention. 相似文献97.
Santo Dellegrottaglie Ana García-Alvarez Pasquale Guarini Pasquale Perrone-Filardi Valentin Fuster Javier Sanz 《Heart & lung : the journal of critical care》2014
Objectives
To evaluate the occurrence of ventricular systolic dysfunction in human immunodeficiency virus (HIV)-related pulmonary arterial hypertension (PAH).Background
Patients with HIV-related PAH may develop ventricular systolic dysfunction both as a consequence of PAH progression or of the myocardial involvement from the HIV infection itself.Methods
Cardiac magnetic resonance imaging was applied to measure ejection fraction for the left ventricle and the right ventricle in patients with HIV-related PAH (n = 27) and in patients with PAH from other aetiologies (n = 115).Results
In HIV-related PAH, ejection fraction values were lower and a higher proportion of patients presented with an advanced stage of ventricular dysfunction (55% vs. 25%; p = 0.009). In a multivariate model, PAH related to HIV infection remained independently associated with advanced ventricular dysfunction (p = 0.011).Conclusions
Patients with HIV-related PAH have more prevalent and severe ventricular systolic dysfunction compared to patients with PAH from other aetiologies. 相似文献98.
Miji Kim Anam Basharat Ramchandani Santosh Syed F. Mehdi Zanali Razvi Sun K. Yoo Barbara Lowell Amrat Kumar Wunnie Brima Ann Danoff Rachel Dankner Michael Bergman Valentin A. Pavlov Huan Yang Jesse Roth 《Diabetes/metabolism research and reviews》2019,35(1)
Over‐nutrition and its late consequences are a dominant theme in medicine today. In addition to the health hazards brought on by over‐nutrition, the medical community has recently accumulated a roster of health benefits with obesity, grouped under “obesity paradox.” Throughout the world and throughout history until the 20th century, under‐nutrition was a dominant evolutionary force. Under‐nutrition brings with it a mix of benefits and detriments that are opposite to and continuous with those of over‐nutrition. This continuum yields J‐shaped or U‐shaped curves relating body mass index to mortality. The overweight have an elevated risk of dying in middle age of degenerative diseases while the underweight are at increased risk of premature death from infectious conditions. Micronutrient deficiencies, major concerns of nutritional science in the 20th century, are being neglected. This “hidden hunger” is now surprisingly prevalent in all weight groups, even among the overweight. Because micronutrient replacement is safe, inexpensive, and predictably effective, it is now an exceptionally attractive target for therapy across the spectrum of weight and age. Nutrition‐related conditions worthy of special attention from caregivers include excess vitamin A, excess vitamin D, and deficiency of magnesium. 相似文献
99.
MRI‐determined lumbar muscle morphometry in man and sheep: potential biomechanical implications for ovine model to human spine translation
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The sheep is a commonly used animal model for human lumbar spine surgery, but only in vitro investigations comparing the human and ovine spine exist. Spinal musculature has previously not been compared between man and sheep. This additional knowledge could further indicate to what extent these species are biomechanically similar. Therefore, the purpose of the study was to investigate spinal muscle morphometric properties using magnetic resonance imaging (MRI) in different age groups of healthy human participants and sheep in vivo. Healthy human participants (n = 24) and sheep (n = 17) of different age groups underwent T1‐weighted MRI of the lumbar spine. Regions of interest of the muscles erector spinae (ES), multifidus (M) and psoas (PS) were identified. The ratio of flexor to extensor volume, ratio of M to ES volume, and muscle fat relative to an area of intermuscular fat were calculated. Sheep M to ES ratio was significantly smaller than in the human participants (sheep 0.16 ± 0.02; human 0.37 ± 0.05; P < 0.001), although flexor to extensor ratio was not significantly different between species (human 0.39 ± 0.08; sheep 0.43 ± 0.05; P = 0.06). Age did not influence any muscle ratio outcome. Sheep had significantly greater extensor muscle fat compared with the human participants (M left human 40.64%, sheep 53.81%; M right human 39.17%, sheep 51.33%; ES left human 40.86%, sheep 51.29%; ES right human 35.93%, sheep 44.38%; all median values; all P < 0.001), although PS did not show any significant between‐species differences (PS left human 36.89%, sheep 33.67%; PS right human 32.78%, sheep 30.09%; P < 0.05). The apparent differences in the size and shape of sheep and human lumbar spine muscles may indicate dissimilar biomechanical and functional demands, which is an important consideration when translating to human surgical models. 相似文献
100.
Wnuk M Hlushchuk R Janot M Tuffin G Martiny-Baron G Holzer P Imbach-Weese P Djonov V Huynh-Do U 《Kidney international》2012,81(12):1212-1225
Eph receptor tyrosine kinases and their ligands (ephrins) have a pivotal role in the homeostasis of many adult organs and are widely expressed in the kidney. Glomerular diseases beginning with mesangiolysis can recover, with podocytes having a critical role in this healing process. We studied here the role of Eph signaling in glomerular disease recovery following mesangiolytic Thy1.1 nephritis in rats. EphB4 and ephrinBs were expressed in healthy glomerular podocytes and were upregulated during Thy1.1 nephritis, with EphB4 strongly phosphorylated around day 9. Treatment with NPV-BHG712, an inhibitor of EphB4 phosphorylation, did not cause glomerular changes in control animals. Nephritic animals treated with vehicle did not have morphological evidence of podocyte injury or loss; however, application of this inhibitor to nephritic rats induced glomerular microaneurysms, podocyte damage, and loss. Prolonged NPV-BHG712 treatment resulted in increased albuminuria and dysregulated mesangial recovery. Additionally, NPV-BHG712 inhibited capillary repair by intussusceptive angiogenesis (an alternative to sprouting angiogenesis), indicating a previously unrecognized role of podocytes in regulating intussusceptive vessel splitting. Thus, our results identify EphB4 signaling as a pathway allowing podocytes to survive transient capillary collapse during glomerular disease. 相似文献