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BACKGROUND AND PURPOSE: Inclusion of oligodendroglial tumors may confound the utility of MR based glioma grading. Our aim was, first, to assess retrospectively whether a histogram-analysis method of MR peifusion images may both grade gliomas and differentiate between low-grade oligodendroglial tumors with or without loss of heterozygosity (LOH) on 1p/19q and, second, to assess retrospectively whether low-grade oligodendroglial subtypes can be identified in a population of patients with high-grade and low-grade astrocytic and oligodendroglial tumors.  相似文献   
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This study examined the impact of a co-occurring personality disorder on the development and remission of posttraumatic stress disorder (PTSD) in 158 motor vehicle accident (MVA) survivors followed prospectively for 1 year. Participants were assessed 1 to 4 months after trauma and at 6-month and 1-year follow-up evaluations during 1991 through 1993. These archival data were analyzed in the present study. The prevalence of at least one personality disorder was 13.3%, with the majority (52.4%) presenting with obsessive-compulsive personality disorder. Persons with a personality disorder were significantly more likely to be diagnosed with PTSD at 1-year follow-up evaluation. For persons diagnosed with PTSD at the initial assessment, those with a personality disorder were significantly less likely to remit by 1 year. The presence of a preexisting personality disorder may increase the risk of chronic PTSD and impede remission.  相似文献   
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5-Fluorouracil in combination with leucovorin has been shown to be active in therapeutic trials of metastatic colorectal carcinoma. In this study, we administered these drugs to 72 patients with metastatic colorectal carcinoma. Thirty-six of them without previous exposure to 5-fluorouracil were treated with weekly bolus injections of 5-fluorouracil (425 mg/m2) and leucovorin (25 mg/m2) supplemented with oral levamisole. Another 36 patients with or without prior 5-fluorouracil treatment received 5-fluorouracil 3,000 mg/m2 and leucovorin 300 mg/m2 in a 48-hour continuous infusion every two weeks. Clinical efficacy and toxicity were assessed by WHO criteria. Variables were tested for relations to response and survival by univariate and multivariate analysis. The response rate was 19.4% in weekly bolus arm and 13.9% in biweekly high-dose infusion arm (P = 0.527). Median survivals in the two arms were 18.4 months (weekly) and 21 months (biweekly) respectively (P = 0.708). Gastrointestinal side effects including nausea, vomiting, diarrhea and mucositia were the major toxicities of these regimens. By multivariate analysis, the only factor to influence response rate was the site of metastases (P = 0.009). The only factor to affect survival was performance status of the patient (P = 0.0001). We concluded that the two 5-fluorouracil based regimens are well-tolerated and shown to have a response rate comparable with previous reports of similar regimens in patients with metastatic colorectal cancer. Only liver metastases seemed to have a better response to therapy. Performance status is the most important prognostic factor in patients with metastatic colorectal cancer.   相似文献   
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Recent reports have demonstrated that the HIV-1 transactivator protein,tat, induces apoptosis in T-lymphocyte cell lines, as well as in peripheral blood mononuclear cells, and stimulates a cascade of events resulting in up-regulation of the potent immunosuppressive cytokine, transforming growth factor-β (TGF-β). In this study we evaluated the ability of TGF-β to mediatetat induced apoptosis in T-lymphocyte cell lines. T-cells treated exogenously with either TGF-β1 or a combination of tat and pan-specific TGF-β neutralizing antibodies showed little change in the amount of apoptosis. When treated with pan-specific TGF-β neutralizing antibodies, Jurkat cells that stably expresstat protein (Jurkat-tat) showed only a modest decrease in apoptosis, while CEM-TART cells (CEM T-cells expressing both HIV-1tat andrev) demonstrated little change in the amount of apoptosis. In conclusion, we have demonstrated that TGF-β does not play a significant role in mediatingtat induced T-cell apoptosis.  相似文献   
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Fatty infiltration of the liver: evaluation by proton spectroscopic imaging   总被引:2,自引:0,他引:2  
Heiken  JP; Lee  JK; Dixon  WT 《Radiology》1985,157(3):707-710
The reliability of proton spectroscopic imaging in evaluating fatty infiltration of the liver was investigated in 35 subjects (12 healthy volunteers and 23 patients with fatty livers). With this modified spin-echo technique, fatty liver could be separated from normal liver both visually and quantitatively. On the opposed image, normal liver had an intermediate signal intensity, greater than that of muscle, whereas fatty liver had a lower signal intensity, equal to or less than that of muscle. In normal livers, the lipid signal fraction was less than 10%, while in fatty livers it was greater than 10% and usually exceeded 20%. With this technique, nonuniform fatty infiltration of the liver can be differentiated from hepatic metastases, and the technique may prove useful in the differentiation of some hepatic disorders.  相似文献   
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BACKGROUND AND OBJECTIVE: Estimates of dietary folate intake are currently of considerable interest, but no rapid tools are available to assess dietary intake of folate that are well suited to everyday health promotion activities. We developed and tested the reliability and validity of two prototypes of a rapid dietary assessment tool (a folate intake tool, FIT) to determine dietary intake of folate. STUDY DESIGN AND SETTING: Five hundred and sixty eight men and women aged 33-83 years from Perth, Western Australia, completed one of the two prototypes of the tool and gave a fasting blood sample for measurement of serum folate. A subset (n=277) of participants completed the same tool on a second occasion 3-6 weeks later. RESULTS: The Pearson correlations (r) between folate score from the tool and serum folate were moderately high for both prototypes (FIT-A r=0.54; FIT-B r=0.49). The folate scores for the two prototypes were similar on repeat testing and correlated strongly (FIT-A r=0.75; FIT-B r=0.68). CONCLUSIONS: The rapid dietary assessment tool described here, FIT, provides a valid and reliable measurement of dietary intake of folate for both men and women.  相似文献   
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