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排序方式: 共有6572条查询结果,搜索用时 15 毫秒
71.
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
72.
73.
Viguié F Aboura A Bouscary D Guesnu M Baumelou E Dreyfus F Casadevall N Tachdjian G 《Cancer Genetics and Cytogenetics》2002,138(1):80-84
The bone marrow karyotypes of three patients with acute myelocytic leukemia (AML) or myelodysplastic syndrome (MDS) were studied at diagnosis and revealed, multiple copies of the same chromosomal anomaly, considered as psu idic(21)(q22) associated with other rearrangement(s). The karyotype of a fourth patient with MDS in transformation showed one copy of a dicentric marker presumably derived from a similar psu idic(21) by (tandem?) interstitial amplification of part of its structure, resembling a "homogeneous staining region", and described as der(21)psu idic(21)(q22)hsr(21)(q22). This rearrangement, previously described in isolated cases only, might be considered as recurrent in AML/MDS and associated with an unfavorable prognosis. It is most probably a secondary change, because it was never observed as sole abnormality and the main association, as for trisomy 21, was with del(5q). In the four cases, the number of partial supernumerary segmental 21pter-->21q22 copies, ranged from 2 to 10. The AML1 gene did not appear to be the common target of this amplification because this locus had been lost by the psu idic(21) in one patient 相似文献
74.
Paul bandenbussche Maurizio Divizia Martine Verhaegeb-Lewalle Akira Fuse Tsuguo Kuwata Erik de Clerq Jean Content 《Virology》1981,111(1):11-22
IFr, a subline of transformed human fibroblast cells, which is sensitive to the antiviral but resistant to the anticellular activity of interferon, was found to be equally well inducible as its parental cell line RSa for the two major interferon-mediated double-stranded RNA-dependent enzymatic activities, 2–5A synthetase and 73K phosphoprotein kinase. The induction of 2-5A synthetase as a function of interferon dose, the specific activity of the 2-5A synthetase, the nature of the 2-5A oligonucleotide products, and the activity of the 2-5A-activated endonuclease were essentially the same for both cell lines. The 73K phosphoprotein kinase was induced at a similar rate of activity, whether detected in solution or after immobilization on poly(I)·poly(C)-Sepharose. Our observations thus suggest that the induction of these two enzymatic activities are not sufficient for the anticellular activity of interferon. 相似文献
75.
Andrew S Artz Daniel A Pollyea Masha Kocherginsky Wendy Stock Elizabeth Rich Olatoyosi Odenike Todd Zimmerman Sonali Smith Lucy Godley Michael Thirman Christopher Daugherty Martine Extermann Richard Larson Koen van Besien 《Biology of blood and marrow transplantation》2006,12(9):954-964
Comorbidity measurements have recently been used to improve estimation of tolerance to allogeneic hematopoietic cell transplantation (HCT). We sought to determine the independent effect of comorbidity and performance status on HCT outcome and to devise a simple risk classification system for transplant-related mortality. We analyzed 105 consecutively enrolled patients who underwent HCT and received reduced intensity conditioning with fludarabine, melphalan, and alemtuzumab. Comorbid conditions were tabulated using 2 scales, the Charlson Comorbidity Index (CCI) and the Kaplan-Feinstein Scale (KFS). Comorbid conditions were found in 47% of patients by the KFS and in 27% by the CCI (P < .001). Using the Eastern Cooperative Oncology Group Performance Status (PS) scale, 34% had a PS score >0 (range, 0-2). A simple scale combining the KFS and PS enabled separation of high- from low-risk patients, with 6-month cumulative incidences 50% and 15%, respectively for transplant-related mortality (P = .001) and enhanced prognostic power over the CCI alone (P = .018). Prospective studies evaluating more comprehensive functional and comorbidity measurements are warranted. 相似文献
76.
Hepatitis E in the south west of France in individuals who have never visited an endemic area 总被引:13,自引:0,他引:13
Mansuy JM Peron JM Abravanel F Poirson H Dubois M Miedouge M Vischi F Alric L Vinel JP Izopet J 《Journal of medical virology》2004,74(3):419-424
A total of 431 consecutive patients from the Midi Pyrenees area with acute hepatitis with unknown etiology in 2001-2002 were tested for the presence of immunoglobulin G-class (IgG) anti-hepatitis E virus (HEV) antibodies. Forty-six (10.7%) had anti-HEV IgG, and the results were questionable for a further 17 (3.9%). Real time PCR based on TaqMan detection was used to identify HEV genome fragments in the serum of patients with positive or questionable anti-HEV serology. HEV RNA was found in 25.4% of cases. All amplification products were sequenced and analyzed. Phylogenetic analysis revealed that all the strains were genotype 3. In conclusion, virological and epidemiological data indicate that genotype 3 viruses are circulating in the south west part of France (Midi-Pyrenees) in patients with acute hepatitis and who have not visited recently areas in which HEV is endemic. 相似文献
77.
Farace F Prestoz L Badaoui S Guillier M Haond C Opolon P Thomas JL Zalc B Vainchenker W Turhan AG 《Stem cells and development》2004,13(1):83-92
Muscle tissue of adult mice has been shown to contain stem cells with hematopoietic repopulation ability in vivo. To determine the functional characteristics of stem cells giving rise to this hematopoietic activity, we have performed hematopoietic reconstitution experiments by the use of muscle versus marrow transplantation in lethally irradiated mice and followed the fate of transplanted cells by Y-chimerism using PCR and fluorescence in situ hybridization (FISH) analysis. We report here that transplantation of murine muscle generate a major hematopoietic chimerism at the level of CFU-C, CFU-S, and terminally-differentiated cells in three generations of lethally irradiated mice followed up to 1 year after transplantation. This potential is totally abolished when muscle grafts were performed by the use of muscle from previously irradiated mice. As compared to marrow transplantation, muscle transplants were able to generate similar potencies to give rise to myeloid, T, B, and natural killer (NK) cells. Interestingly, marrow stem cells that have been generated in primary and then in secondary recipients were able to contribute efficiently to myofibers in the muscle tissue of tertiary recipients. Altogether, our data demonstrate that muscle-derived stem cells present a major hematopoietic repopulating ability with evidence of self-replication in vivo. They are radiation-sensitive and similar to marrow-derived stem cells in terms of their ability to generate multilineage hematopoiesis. Finally, our data demonstrate that muscle-derived hematopoietic stem cells do not lose their ability to contribute to myofiber generation after at least two rounds of serial transplantation, suggesting a potential that is probably equivalent to that generated by marrow transplantation. 相似文献
78.
Isabelle Garrigue Sébastien Boucher Lionel Couzi Anne Caumont Claire Dromer Martine Neau-Cransac Reza Tabrizi Marie-Hélène Schrive Hervé Fleury Marie-Edith Lafon 《Journal of clinical virology》2006,36(1):72-75
BACKGROUND: Cytomegalovirus (CMV) remains a major opportunistic agent among transplant recipients. While detection of CMV pp65-lower matrix protein (pp65Ag) is still widely used for monitoring CMV infection, real-time PCR assays have been recently developed for routine quantitation of CMV DNA. However, correlations are lacking between results of pp65Ag and quantitative PCR assays and there is no consensus yet as to the more appropriate blood compartment (whole blood (WB), leukocytes, plasma) to be tested with PCR assays. OBJECTIVES: The aims of the study were to determine, in a population of transplant recipients: (i) the correlation between pp65Ag and CMV quantitative real-time PCR in our setting and (ii) the utility of plasma CMV DNA quantitation in comparison to WB quantitation. METHODS: In 170 blood samples (from 61 solid organ or bone marrow transplant recipients) with pp65Ag results, CMV quantitation was performed in WB and plasma using an in-house real-time quantitative PCR. RESULTS: Real-time PCR and pp65Ag results in WB were correlated: thresholds of 10 and 50(+) cells/200,000 cells were equivalent to 3.3 log(10)copies/mL (2,000 copies/mL) and 3.8 log(10)copies/mL (6,300 copies/mL), respectively. When WB viral load was >or=3.6 log(10)copies/mL, the risk to have a negative plasma CMV DNA result was 相似文献
79.
Joannis Theodorou Martine Raphaël Claude Bigorgne Christine Fourcade Chantal Lahet Gilles Cochet Marie-Paule Lefranc Philippe Gaulard Jean-Pierre Farcet 《The Journal of pathology》1994,174(4):233-242
The recombination events of the γ and β T-cell receptor (TCR) loci were analysed in a series of 39 peripheral T-cell lymphomas (PTCLs) in association with the expression of TCR chains. In TCR αβ PTCLs, 22/23 cases showed a γ-gene rearrangement while only 18/23 showed a concomitant β-gene rearrangement. The germline configuration of the β locus was found in angioimmunoblastic lymphadenopathy and lymphoepithelioid lymphomas. Three γδ PTCLs rearranged both γ and β genes. TCR silent PTCLs showed three different patterns of γ- and β-gene rearrangements. Three cases were in germline configuration for both loci; five cases had a rearranged γ and a germline β locus; and five cases had the two loci rearranged. Regarding the variable genes in the γ-rearranged alleles, members of the VγI subgroup were the most frequently presented (39/50), followed by VγII, VγIII, and VγIV (9/50, 1/50, and 1/50, respectively). Joining segment usage was as follows: J1 or J2 (32/50), JP1 or JP2 (17/50), and JP (1/50). Taken together, these data demonstrate that the γ locus is more frequently rearranged whatever the TCR expression. The γ-locus analysis provides a better diagnostic yield than the β locus in the study of PTCL clonality. 相似文献
80.