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Viard A Flament MF Artiges E Dehaene S Naccache L Cohen D Mazet P Mouren MC Martinot JL 《Psychological medicine》2005,35(7):1007-1017
BACKGROUND: Failure to resist chronic obsessive-compulsive symptoms may denote an altered state of cognitive control. We searched for the cerebral regions engaged in this dysfunction. METHOD: Differences in brain regional activity were examined by event-related functional magnetic regional imaging (fMRI) in a group of adolescents or young adults (n = 12) with childhood-onset obsessive-compulsive disorder (OCD), relative to healthy subjects. Subjects performed a conflict task involving the presentation of two consecutive and possibly conflicting prime and target numbers. Patients' image dataset was further analysed according to resistance or non-resistance to symptoms during the scans. RESULTS: Using volume correction based on a priori hypotheses, an exploratory analysis revealed that, within the prime-target repetition condition, the OCD subjects activated more than healthy subjects a subregion of the anterior cingulate gyrus and the left parietal lobe. Furthermore, compared with 'resistant' patients, the 'non-resistant' OCD subjects activated a bilateral network including the precuneus, pulvinar and paracentral lobules. CONCLUSIONS: Higher regional activations suggest an abnormal amplification process in OCD subjects during the discrimination of repetitive visual stimuli. The regional distribution of functional changes may vary with the patients' ability to resist obsessions. 相似文献
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In this study, we measured the phenology of Ixodes ricinus ticks and their infection with Borrelia burgdorferi sensu lato (sl) simultaneously along an altitudinal gradient to assess the impact of climate on the phenology of ticks and on their infection with B. burgdorferi sl. From 1999 to 2001, free-living I. ricinus ticks were collected monthly by flagging vegetation at three different altitudes (620, 740, and 900 m above sea level) on the slope of a mountain in Chaumont (Neuchatel, Switzerland). I. ricinus ticks were examined for the presence of B. burgdorferi sl by using direct fluorescent antibody assay and isolation of spirochetes. Borrelia species were characterized by polymerase chain reaction followed by restriction fragment-length polymorphism. Tick density and tick phenology varied with altitude. Although the peak tick density decreased and the onset of ticks was delayed with altitude, the phenology was much more stable among years at the highest altitudes than at the lowest. The prevalence of B. burgdorferi infection in nymphs and adults decreased with altitude. The prevalence of infection differed significantly among years, and it was significantly higher in adults (30%) than in nymphs (21%). B. burgdorferi infection in adults was positively related with adult density, but this was not observed for nymphs. Five B. burgdorferi sl genospecies were successfully isolated: B. garinii, B. burgdorferi sensu stricto, B. afzelii, B. valaisiana, and B. lusitaniae. Mixed infections were obtained from five of 140 infected ticks. The greatest diversity in Borrelia species was observed at the lowest altitude where all five Borrelia species were present, whereas at the two highest altitudes, B. lusitaniae was not observed. 相似文献
25.
Clavert P Kempf JF Wolfram-Gabel R Kahn JL 《Surgical and radiologic anatomy : SRA》2005,27(5):385-388
Different anterosuperior aspects of the glenoid labrum have already been described and are thought to be normal anatomical
variations. The goals of this study were first to characterize these anterosuperior labral morphologies and then to analyze
their variations in function of the patients’ age. One hundred shoulder arthroscopies were recorded to study the macroscopic
characteristics of the anterosuperior labrum of the glenohumeral joint and its relationships with the proximal insertion of
the tendon of the long head of the biceps. Then, patients were divided into two groups in function of their age (below and
over 30 years old). Morphological modifications of the labrum were found in function of the age of the patient with an increase
of the nonpathologic “mobile labrum” type after 30 years (P=0.0423). Therefore a mobile and loosely attached superior labrum should not always be considered as abnormal, especially
in case of patient older than 30 years. 相似文献
26.
Value of microimmunofluorescence for diagnosis and follow-up of Bartonella endocarditis 总被引:3,自引:0,他引:3
Bartonella endocarditis is a disease of emerging importance that causes serious complications and high rates of mortality. Due to the fastidious nature of Bartonella species and their high degrees of antibiotic susceptibility, cultures of clinical samples most often remain sterile and valvular biopsy specimens, the best specimens for PCR amplification, are seldom available. Therefore, serology appears to be the easiest diagnostic tool. In order to determine the best cutoff value for serology and its predictive values for the detection of Bartonella endocarditis, we studied 48 patients with culture- and/or PCR-confirmed Bartonella endocarditis. We also applied these serological criteria to 156 patients with blood culture-negative endocarditis. Furthermore, we compared the kinetics of the antibody responses to Bartonella spp. in order to estimate the value of serology for prediction of the occurrence of relapses. A titer of > or = 1:800 for immunoglobulin G antibodies to either Bartonella henselae or B. quintana has a positive predictive value of 0.810 for the detection of chronic Bartonella infections in the general population and a value of 0.955 for the detection of Bartonella infections among patients with endocarditis. When this cutoff was applied to 156 patients with blood culture-negative endocarditis, we were able to diagnose Bartonella infections in an additional 45 patients with definite endocarditis for whom a positive Bartonella serology was the only evidence of infection. On follow-up, the kinetics of the decrease in antibody titers were significantly delayed in two patients with relapses. In conclusion, we recommend the determination of antibodies to both B. quintana and B. henselae and the use of a cutoff value of 1:800 for the diagnosis of Bartonella endocarditis. We propose that this criterion, which may also help with the detection of late relapses, be included as a major criterion in the Duke criteria for the diagnosis of infective endocarditis. 相似文献
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Prince Kevin Danieles Marina Ybarra Andraea Van Hulst Tracie A. Barnett Marie-Ève Mathieu Lisa Kakinami Olivier Drouin Jean-Luc Bigras Mélanie Henderson 《Obesity research & clinical practice》2021,15(2):157-162
IntroductionAttrition in pediatric weight management programs is notoriously high. Greater understanding of its determinants is needed to inform retention strategies. We identified determinants of attrition in CIRCUIT, a healthy lifestyle intervention program for youth at risk of cardiovascular disease.MethodsA one-arm intervention study of children aged 4-18 years who initiated the CIRCUIT program in the first five years of its existence (N = 403). We defined attrition as attending the baseline visit but ceasing attendance prior to the 1-year follow-up. Potential determinants of dropout included the child’s age, sex, ethnicity, body mass index (BMI) z-score, family socio-demographic characteristics, and estimated driving time to the program, all measured at baseline. Associations were estimated bivariately, using chi-squared- and t-tests, and simultaneously in a multivariable logistic regression model.ResultsOf the 403 participants who started the program, 198 (49%) dropped out within 12 months of enrollment. Youth who dropped out were older (mean age 12.8y vs. 11.3y; p < 0.01), were less likely to live with both parents (62% vs. 71%; p = 0.05), and to have mothers who had completed high school (79% vs. 88%; p = 0.01). No group differences were observed for sex, ethnicity, baseline BMI z-score, fathers’ education, or driving time to the program. In multivariate models, only older age at initiation of the intervention (OR: 1.2; CI: 1.1,1.3) and lower maternal education (OR: 2.0; CI: 1.0,3.8) were associated with dropout.ConclusionImproved tailoring of interventions to older pediatric participants and to families of lower maternal education may help reduce attrition in CIRCUIT and similar lifestyle intervention programs. 相似文献
29.
Andry Perrin Wulphert Venderink Michael A. Patak Claudius Möckel Jean-Luc Fehr Patrice Jichlinski Beat Porcellini Ilaria Lucca Jurgen Futterer Massimo Valerio 《Urologic oncology》2021,39(5):297.e9-297.e16
ObjectivesTo evaluate the utility of in-bore multiparametric magnetic resonance-guided biopsy of the prostate (IB) in patients with visible lesion/s and previous negative software-based multiparametric magnetic resonance imaging/ultrasonography fusion-targeted biopsy of the prostate (FTB).Patients and methodsWe retrospectively analysed prospectively maintained database including consecutive men undergoing IB from March 2013 to October 2017 in 2 European centres expert in this procedure. We selected men with the following criteria: No previous treatment for prostate cancer (CaP), multiparametric magnetic resonance imaging (mpMRI) lesion(s) PIRADS score ≥ 3, FTB showing no clinically significant cancer (csCaP), and subsequent IB. Patient's characteristics, mpMRI findings, biopsy technique, and histopathological results were extracted. The primary outcome was to determine the detection rate of csCaP, defined as any Gleason pattern ≥ 4. A multivariable analysis was performed to identify predictors of positive findings at IB.ResultsFifty-three men were included. Median age was 68 years (interquartile range [IQR] 64–68), median Prostate-Specific Antigen (PSA) was 7.6 ng/ml (IQR 5.2–10.9), and median prostate volume was 59 ml (IQR 44–84). Fifty-six lesions with PIRADS score 3 in 9 cases (16%), 4 in 30 cases (54%), and 5 in 17 cases (30%) were detected. FTB was performed in all cases using a transrectal approach with 3 different platforms (Toshiba, Koelis, and Artemis). Median time between FTB and IB was 3 months (IQR 1–7). A median of 2 cores per lesion were collected with IB (IQR 2–3). No cancer, clinically insignificant and clinically significant cancer were found in 33 (59%), 9 (16%), and 14 (25%) targeted lesions, respectively. Median maximum cancer core length and maximum positive percentage were 9 mm (3–13) and 55% (21%–80%). The only predictor of csCaP on IB was prostate volume (P = 0.026) with an ideal cut-off at 70 ml.ConclusionOne in 4 patients with previous negative FTB, IB was able to detect csCaP. According to this study, IB would be of particularly useful in patients with large glands. 相似文献
30.
Valrie Kouskoff Jean-Luc Vonesch Christophe Benoist Diane Mathis 《European journal of immunology》1995,25(1):54-58
The expression of recombination activating gene (RAG) products, responsible for T cell receptor (TcR) gene rearrangement, is shut off during positive selection of thymocytes. The precise stage at which this down-regulation occurs remains somewhat controversial. We have analyzed RAG-1 expression in thymocytes of TcR transgenic mice carried on selecting versus non-selecting genetic backgrounds, both by in situ hybridization on thymus sections and by polymerase chain reaction amplification of RNA from sorted cells. The data from several transgenic lines indicate that RAG expression is already reduced in immature, cortical, CD4+CD8+ cells in the presence of positively selecting major histocompatibility complex molecules, although complete shut-off is not achieved until the mature, medullary, single-positive stage. This finding has practical and theoretical significance for studies on the mechanism of positive selection. 相似文献