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111.
A C Begg I Hofland L Moonen H Bartelink S Schraub P Bontemps R Le Fur W Van Den Bogaert R Caspers M Van Glabbeke 《International journal of radiation oncology, biology, physics》1990,19(6):1449-1453
The value of cell kinetic measurements in head and neck tumors in predicting which patients will benefit from accelerated fractionation radiotherapy regimens is being tested in a multicenter European trial (EORTC trial 22851). This paper reports on the first analysis of the correlation of kinetics with outcome in this trial. A proportion of patients in both the accelerated arm (72 Gy in 5 weeks, 1.6Gy per fraction, 45 fractions) and the conventional arm (70-72 Gy in 7-8 weeks, 1.8-2.0 Gy per fraction, 35-40 fractions) were given an i.v. injection of 100 mg/m2 IUdR (iododeoxyuridine) before treatment, and a tumor biopsy was taken several hours later. The potential doubling time of the tumor (Tpot) was obtained from a flow cytometric analysis of tumor cell nuclei using an anti-IUdR antibody. From a total of 260 patients entered in the trial, 53 have undergone kinetic analysis. Adequate IUdR labeling was seen in 47 patients (88.7%), from which the mean value for Tpot was found to be 4.5 +/- 2.5 days (+/- S.D.). Of the IUdR labeled patients, 30 have now been followed up for at least 1 year, 17 with conventional and 13 with accelerated radiotherapy. These patients were split into those with fast and those with slowly growing tumors, the dividing line being the median Tpot value of 4.6 days. After conventional 7-week radiotherapy, 2 of 6 patients with "fast" growing tumors obtained local control compared with 8 of 11 with "slow" growing tumors. A small difference in local control was seen been fast and slow tumors in the accelerated arm (5/9 vs. 3/4). These preliminary data support the hypothesis that patients with fast growing tumors do poorly with conventional radiotherapy and that pretreatment kinetic measurements can select patients at risk. The predictive power of the method must await the final analysis of trial results. 相似文献
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Staging of lymph nodes with FDG dual-headed PET in patients with non-small-cell lung cancer 总被引:2,自引:0,他引:2
Stokkel MP Bakker PF Heine R Schlösser NJ Lammers JW Van Rijk PP 《Nuclear medicine communications》1999,20(11):1001-1007
Accurate assessment of mediastinal lymph node involvement in patients with non-small-cell lung cancer (NSCLC) is necessary to select patients for direct surgical treatment. The aims of the present study were to assess the feasibility of staging NSCLC with FDG using a dual-headed positron emission tomographic (PET) camera and to compare this non-invasive technique with computed tomography (CT) and lymph node sampling, since both modalities are currently used for staging NSCLC. Thirty-three patients (29 men and 4 women, mean age 60 years) with newly diagnosed NSCLC were studied. In all patients, CT, FDG dual-headed PET and mediastinoscopy were performed within 4 weeks. The results of mediastinoscopy were used to select patients for thoracotomy. For both the assessment of individual lymph node involvement and the patient-based classification, the results of FDG dual-headed PET and CT were compared using the McNemar test. Thirty-one of 187 lymph nodes studied contained tumour metastases. FDG dual-headed PET showed a significantly higher sensitivity (P < 0.001) and specificity (P < 0.001) than CT. FDG dual-headed PET and CT correctly staged 27 and 20 patients, respectively. Due to the significantly higher negative predictive value of FDG dual-headed PET versus CT (P = 0.012), it was a better non-invasive diagnostic tool for selecting patients for surgery. In seven of eight patients, additional intrapulmonary sites of increased uptake were found, which revealed malignancy on histological examination. CT was false-negative in three of these patients. In one patients, increased FDG uptake was caused by an infection. In conclusion, it is possible to stage mediastinal lymph nodes in patients with NSCLC using a dual-headed PET camera. The high negative predictive value of FDG dual-headed PET suggests that mediastinoscopy may be omitted in patients with NSCLC. 相似文献
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Bakker A van Dyck R Spinhoven P van Balkom AJ 《The Journal of clinical psychiatry》1999,60(12):831-838
BACKGROUND: This 12-week, placebo-controlled study was carried out to compare the relative efficacy of paroxetine, clomipramine, and cognitive therapy in the treatment of DSM-III-R-defined panic disorder with or without agoraphobia. METHOD: After a 3-week single-blind, placebo run-in period, 131 patients were randomly assigned to receive double-blind medication or 12 sessions of cognitive therapy based on the model of Clark. Efficacy assessments included the daily panic attack diary, the Clinical Global Impression scale, the Patient Global Evaluation, the Hamilton Rating Scale for Anxiety, the Marks-Sheehan Phobia Scale, the Montgomery-Asberg Depression Rating Scale, and the Sheehan Disability Scale. RESULTS: Comparisons with placebo revealed significant superiority of paroxetine (20-60 mg/day) and clomipramine (50-150 mg/day) on nearly all outcome measures. On most measures, paroxetine also showed higher efficacy than cognitive therapy. With few exceptions, cognitive therapy did not differ significantly from placebo. The number of subjects becoming panic-free (66%) was higher and the onset of action was faster in the paroxetine-treated group. Treatment with cognitive therapy yielded the highest drop-out rate (26%). CONCLUSION: In this short-term study assessing treatment of panic disorder and agoraphobia, paroxetine and clomipramine were consistently superior to pill placebo, whereas cognitive therapy was superior on only a few measures. 相似文献
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Preoperative evaluation of living renal donors with gadolinium-enhanced magnetic resonance angiography 总被引:4,自引:0,他引:4
BACKGROUND: Preoperative evaluation of living renal donors includes an intra-arterial digital subtraction angiography (DSA). Inasmuch as this technique is invasive, uses radiation and an iodine-containing contrast medium, an alternative technique would be preferable. The purpose of this study was to determine the accuracy of gadolinium-enhanced magnetic resonance (MR) angiography in the visualization of renovascular anatomy for the preoperative evaluation of renal donors. METHODS: Twenty-four consecutive potential renal donors underwent gadolinium-enhanced MR angiography before the standard of reference, intra-arterial DSA. Both modalities were evaluated in a blinded manner. The results were correlated with the surgical findings. RESULTS: Three MR angiograms were technically unacceptable because of inadequate breath-hold. The remaining 21 donors had 47 renal arteries, including 5 accessory renal arteries, which were all visualized by MR angiography. MR angiography failed to visualize one case of subtle fibromuscular dysplasia in the distal part of a renal artery. In one donor, a small accessory renal artery, which had not been visualized on DSA, was encountered during nephrectomy. CONCLUSION: Gadolinium-enhanced MR angiography is an accurate minimally invasive method for the detection of accessory renal arteries in the preoperative evaluation of potential renal donors. The accuracy for excluding stenosis in general is high; however, the depiction of stenosis that are located far distally, or in the branch vessels, is less accurate. Advantages of gadolinium-enhanced MR angiography over the currently used method, intra-arterial DSA, are the minimal invasive nature, lower costs, and superiority in detecting venous anomalies, renal cysts, and tumors. 相似文献
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Functional assessment of sciatic nerve reconstruction: biodegradable poly (DLLA-epsilon-CL) nerve guides versus autologous nerve grafts 总被引:1,自引:0,他引:1
Meek MF Dijkstra JR Den Dunnen WF Ijkema-Paassen J Schakenraad JM Gramsbergen A Robinson PH 《Microsurgery》1999,19(8):381-388
The aim of this study was to compare functional nerve recovery after reconstruction with a biodegradable p(DLLA-epsilon-CL) nerve guide filled with modified denatured muscle tissue (MDMT), or an autologous nerve graft. We evaluated nerve recovery using walking track analysis (measurement of the sciatic function index [SFI]) and electrostimulation tests. Functional nerve recovery after reconstruction with a biodegradable p(DLLA-epsilon-CL) nerve guide filled with MDMT was faster when compared with nerve reconstruction using an autologous nerve graft. We conclude that in case of a short nerve gap in the rat, reconstruction can best be carried out using a p(DLLA-epsilon-CL) biodegradable nerve guide filled with MDMT. 相似文献