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BACKGROUND: The National Acute Spinal Cord Injury Studies have been a series of trials assessing the role of pharmacologic agents in the prevention of secondary neuronal damage after acute spinal cord injury. METHODS: The trials were multicenter randomized, controlled studies. RESULTS: Two trials have demonstrated the efficacy of high-dose methylprednisolone in improving neurologic and functional recovery and have shown a reassuring safety profile. CONCLUSION: This study responds to a recent commentary on these trials and examines in particular the roles of clinical measurement, statistical analysis, and risk benefit in assembling evidence for or against innovative therapies.  相似文献   
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PURPOSE: The reliability of immunohistochemistry for subdividing diffuse large B-cell lymphomas (DLBCL) into germinal center B-cell-like (GCB) and non-GCB prognostic subgroups is debated. In this study we evaluated the prognostic significance of such subgrouping on a series of 153 DLBCL patients. Furthermore, we investigated whether both subgroups could comprise clinicopathologic entities recognized by their morphology and characterized by a distinct phenotype, specific genetic abnormalities, and clinical characteristics. PATIENTS AND METHODS: All samples from patients were reviewed and morphologically subdivided into large cleaved, immunoblastic, and not otherwise specified DLBCL. GCB and non-GCB immunohistochemical profiles were established. The presence of chromosomal translocations involving BCL2, BCL6, and MYC and/or rearrangements of these genes was investigated. RESULTS: Subdividing DLBCL with either a GCB or non-GCB immunophenotypic profile was not of prognostic significance. Nevertheless, CD10 expression was a predictor of favorable outcome, whereas high bcl-2 expression and BCL6 rearrangement were adverse predictors of disease-free survival. Interestingly, large cleaved DLBCL was clearly associated with a GCB immunophenotypic profile, CD10 expression, BCL2 rearrangement, age younger than 60 years, and low to low/intermediate International Prognostic Index risk, but was not of prognostic significance. In contrast, immunoblastic morphology was associated with a non-GCB profile and was a significant predictor of unfavorable DFS. CONCLUSION: Subdividing DLBCL into subgroups based on their immunohistochemical profile was not of prognostic significance. Nevertheless, it allowed the additional characterization of two lymphoma subgroups previously recognized in the Working Formulation. Both correspond to two distinct clinicopathologic entities within the DLBCL.  相似文献   
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Le Posttraumatic Cognitions Inventory (PTCI) is one of the most used instruments to assess posttraumatic cognitions. Since its release, many studies have tried to validate and translate this questionnaire, but they had difficulty to confirm its structure and then suggested alternatives. Faced with no consensus, a short version in nine statements was developed and showed good psychometric properties. To date, no French version of the PTCI has been validated, thereby preventing studies from investigating the role of posttraumatic cognitions in French speaking populations.ObjectivesIn order to validate a French version of the PTCI, this study investigates two objectives using two French speaking samples: (1) test 10 factor structures identified in prior studies, and (2) assess the other psychometric properties of the best fitting factor structure.MethodThe PTCI was translated in French using a reverse translation method and administered to 202 university students and 114 aid workers. Suitability indexes of the appropriate factor structures previously identified in prior studies were examined. Internal consistency, correlations between subscales and convergent, divergent and discriminant validities in the most appropriate structure were evaluated.ResultsResults support that only Wells et al.''s short 9-item version of the PTCI and three factors shows excellent suitability indexes. This version also outlines an excellent internal consistency and solid convergent, divergent, and discriminant validities.ConclusionsThis study confirms the empirical validity, fidelity, and utility of Wells et al.''s short version of the PTCI. This is the first PTCI French validation, which is a major advantage when it comes to assess posttraumatic cognitions in French trauma victims.  相似文献   
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Squamous cell carcinoma of the anal canal (SCCA) is a rare HPV‐associated cancer with limited sensitivity to standard chemotherapy. In a phase 2 study, nivolumab, an anti PD‐1 immune checkpoint inhibitor, demonstrated significant efficacy as single‐agent therapy in metastatic SCCA patients. Nevertheless, imaging assessment by standard RECIST criteria of the efficacy of immune therapy can be difficult in some patients due to tumor immune cell infiltration, and biomarkers of treatment efficacy are needed. We have previously developed a quantitative droplet digital PCR (ddPCR) technique to detect HPV circulating tumor DNA (HPV ctDNA), with excellent sensitivity and specificity. Here, we report, for the first time, the kinetics of HPV ctDNA during therapy in a patient with metastatic SCCA, who obtained sustained partial response to single‐agent nivolumab. We observed an early and very significant decrease of HPV ctDNA during therapy from the baseline level of 3713 copies/ml plasma to 564 copies/ml plasma at 4 weeks, and 156 copies/ml at 6 weeks, followed by a plateau. This observation provides proof‐of‐concept that HPV ctDNA can be used as a noninvasive early dynamic biomarker to monitor the efficacy of new immunotherapy agents.  相似文献   
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OBJECTIVE: The aim of the study was to assess the rate of acceptance of preimplantation genetic diagnosis (PGD) as an alternative to prenatal diagnosis in Lebanese women with previously affected children with homozygous beta-thalassemia. METHODS: Women with a previously affected child attending a nongovernmentally funded thalassemia care center between 1 June 2005 and 31 May 2007 were offered a genetic counseling session. This was followed by administering a questionnaire through direct interview. RESULTS: All 97 women approached accepted to participate in the study (100% response rate). Sixty eight per cent of women considered PGD a better alternative to prenatal diagnosis. The most important perceived advantage of PGD was the avoidance of termination of an affected pregnancy. CONCLUSIONS: PGD is an acceptable alternative to conventional prenatal diagnosis in women at risk of conceiving a child affected with beta-thalassemia. This is particularly true in countries of the Middle-East where therapeutic abortions for fetal indications are prohibited by the law and religion. Copyright (c) 2008 John Wiley & Sons, Ltd.  相似文献   
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OBJECTIVE: To evaluate whether fetal brain magnetic resonance imaging (MRI) adds useful information to the one obtained by ultrasound in fetuses with cytomegalovirus (CMV) infection. METHODS: MRI and ultrasonographic findings were analyzed retrospectively in 38 fetuses with proven congenital CMV infection. Both techniques were performed on the same week at a mean gestational age of 33 weeks (24-37). The referral indications were maternal seroconversion (n = 19), and ultrasound findings (n = 19). The results were compared with the fetopathologic examination in cases with fetal death or termination of pregnancy (TOP) or the infant's neurological examination. RESULTS: The 38 cases were classified into three groups, depending on ultrasound findings at referral. Group 1: no ultrasound features (n = 11); group 2: extracerebral features without cerebral abnormalities at ultrasound (n = 13); group 3: presence of cerebral features at ultrasound (n = 14). In group 1, MRI was always normal. In group 2, MRI revealed cerebral features in six cases (46%). In group 3, MRI always confirmed the lesions seen at ultrasound and highlighted other cerebral features. CONCLUSIONS: MRI can provide important additional information with regard to abnormal gyration, cerebellar hypoplasia, or abnormal signal in white matter. It is certainly useful in the assessment of fetuses with extracerebral features without brain abnormalities detected with ultrasounds. If the fetal ultrasound is strictly normal in an infected fetus, MRI may not detect brain anomalies; however, it seems difficult to not perform this noninvasive procedure.  相似文献   
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