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Rosa van Mourik Jaap Oosterlaan Dirk J Heslenfeld Claudia E Konig Joseph A Sergeant 《Clinical neurophysiology》2007,118(8):1855-1865
OBJECTIVE: Although an increased distractibility is one of the behavioral criteria of Attention Deficit Hyperactivity Disorder (ADHD), there is little empirical evidence that children with ADHD are in fact more distractible than their normal peers. METHODS: We recorded event-related potentials (ERPs) to distracting novel sounds (novels) and standard sounds, (standards) while children performed a visual two-choice reaction time task. Twenty-five children with ADHD were compared with eighteen normal controls (aged 8-12 years). RESULTS: Children with ADHD showed a larger early P3a (150-250 ms), both in response to the standard and in response to the novel. The late phase of the P3a had a larger amplitude in the ADHD group in the 250-300 ms window compared to the control group, which was only present in response to the novel. Interestingly, the novel reduced the errors of omission in the ADHD group to a greater extent than in the normal control group. CONCLUSIONS: Although children with ADHD show an increased orienting response to novels, this distracting information can enhance their performance temporarily, possibly by increasing their arousal to an optimal level, as indicated by the reduced omission rate. SIGNIFICANCE: These data indicate that distraction is not always distracting in children with ADHD and that distraction can also have beneficial effects. 相似文献
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Combined approach of FTIR imaging and conventional dissolution tests applied to drug release. 总被引:1,自引:0,他引:1
A new method is developed to study drug release using a combination of FTIR imaging and conventional dissolution tests. FTIR imaging in attenuated total reflection (ATR) mode allows simultaneous measurements of the distribution of different components in the tablet, e.g., drug, polymer and water as a function of time. These imaging measurements were carried out in a combined compaction and flow-through cell, which was linked to a UV detector to quantify the amount of dissolved drug. In this way, changes in drug concentration in the aqueous solution can be studied similarly to the conventional dissolution test. This combination provides quantitative information of changes in both the tablet and the liquid phase. A tablet composed of hydroxypropyl methylcellulose (HPMC) and niacinamide was prepared and analysed using this setup. Mathematical processing of the measured spectra with a partial least squares (PLS) calibration was utilised for accurate quantitative analysis of the concentrations of different components. The results of FTIR imaging and the dissolution test are compared. 相似文献
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J. H. M. Blom F. J. W. Ten Kate F. H. Schroeder R. O. van der Heul 《Urological research》1990,18(2):93-99
Summary At present there are several grading systems for prostatic carcinoma. Most are difficult to reproduce. An objective method of grading seems to be necessary and could make comparisons between various groups of patients easier and grading more reliable.In the present study morphometrically estimated nuclear size and variation in nuclear size are matched with the survival rates of 207 patients who underwent total perineal prostatetomy for cancer. On the basis of morphometrically estimated variation in nuclear size the patients could be divided into two groups with significantly differing survival rates. In this way it was possible to split the group of patients with grade 2 carcinoma (Mostofi's grading system) into two groups of patients with significantly different survival rates. The survival rates in these two groups did not differ significantly from those in the patients with Grade 1 and Grade 3 tumors respectively.The results are discussed in the light of the recent literature on the subject. Morphometry seems to be a valuable tool in grading prostatic cancer. 相似文献
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Auke J. S. Renard Ren P. H. Veth Maciej Pruszczynksi Jaap Hoogenhout Jos Bkkerink Frans J. M. Van Der Staak Theo Wobbes Josef A. M. Lemmens Ren van Hoesel Jim R. Van Horn 《Journal of surgical oncology》1995,60(4):250-256
This paper describes 29 patients with Ewing's sarcoma of bone treated between 1975 and 1990 at the University of Nijmegen Hospital, Nijmegen, The Netherlands. Osteomyelitis was the primary diagnosis in 24%. Treatment consisted of chemotherapy in combination with surgery and/or radiotherapy. Nine patients received radiotherapy only; five of them died of disease. Five patients underwent an intralesional excision; four of them died of disease. Twelve patients underwent a wide excision; there is no evidence of disease in any of them. Three patients underwent a radical disarticulation; all died of disease. The disease-free survival at 1.5 years was 66%. This figure at 5 years was 55%. After wide excision and reconstruction in tumors of expendable, femoral or radial bones good functional results were obtained in all cases. © 1995 Wiley-Liss, Inc. 相似文献
16.
Gijs A. Kleter Jan J. M. Damen Mark J. Buijs J. M. Ten Cate 《European journal of oral sciences》1997,105(3):278-284
The Maillard reaction between carbohydrate and protein has been proposed as a cause of the browning of carious lesions. The aim of the present investigation was to determine the occurrence of this reaction in bovine dentin collagen in vitro and to establish the effect of the reaction on the proteolytic degradation of bovine dentin collagen in vitro. Slices of demineralized bovine dentin were incubated with 0.2 M glucose or buffer for 10 weeks at 37°C. The formation of initial (furosine) and advanced (pentosidine) products of the Maillard reaction in dentin exposed to glucose was confirmed by HPLC. After reduction with NaBH4 to prevent intermediate Maillard products from further reaction, slices were either degraded with collagenase for fluorescence measurement or incubated with trypsin or pepsin to assess enzymatic degradation. Fluorescence characteristic for the Maillard reaction increased in glucose-exposed slices. Degradation of collagen by pepsin, but not by trypsin, was greatly depressed following glucose pretreatment. This may indicate an altered sensitivity to proteolytic degradation; the Maillard reaction thus has a potential role in caries arrestment. 相似文献
17.
S Rodenhuis L T Vlasveld R Dubbelman R Roodbergen J H Schornagel J Wanders S P Israels E Bais W W Ten Bokkel Huinink D J Richel 《Annals of oncology》1992,3(6):463-467
Eleven patients with testicular cancer, either relapsing after or refractory to cisplatin-based chemotherapy, underwent salvage chemotherapy with high-dose carboplatin (800 mg/m2 on day 1) and high-dose etoposide (500 mg/m2 on days 1, 3 and 5). A total of 21 courses were administered. The major toxicity consisted of profound myelosuppression. There were two toxic deaths, both caused by infection during neutropenia. Bone marrow recovery was usually complete around day 26 (range 19-129). Other toxicities included mild mucositis, nausea and vomiting, and alopecia. No significant neurotoxicity or hearing loss were observed and only one patient had a moderate decrease in renal function. Nine of ten evaluable patients responded, with one complete remission, 6 partial remissions with normalization of tumor markers, and two partial remissions with over one log decrease of tumor markers. The duration of these remissions was not evaluable, since only three evaluable and responding patients did not receive additional therapy after HD-CE. All three relapsed after discontinuing chemotherapy. HD-CE has activity in relapsing or refractory testicular cancer and can be administered without bone marrow support. The regimen may thus be suitable to be used as a remission induction regimen prior to consolidation with intensive chemotherapy and autologous bone marrow transplantation. 相似文献
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Testing the capacity of the trunk extensor muscles may be useful in the diagnosis of low back pain. In the present study, the reproducibility of measurements of maximum trunk extension force, trunk extension endurance, and related electromyographic parameters was investigated. Intraclass correlations indicated that the reproducibility of maximum force and endurance time was satisfactory. Nevertheless, the smallest difference in these parameters that could be attributed, with 95% confidence, to a change in the condition of a patient was, in general, more than 20%. On the electromyograms, the slopes of amplitude and frequency content appeared to be related to endurance time. The reproducibility of these parameters in terms of the intraclass correlation was again satisfactory; however, the smallest detectable difference generally exceeded 50%. The clinical applicability of the parameters studied is severely limited by a lack of reproducibility. 相似文献