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A Rougereau O Person G Rougereau 《International journal for vitamin and nutrition research. Internationale Zeitschrift für Vitamin- und Ern?hrungsforschung. Journal international de vitaminologie et de nutrition》1987,57(1):19-23
In a previous article we have reported our finding of an unknown vitamin derivative in the serum of cancer patients and in rats transplanted by a malignant tumor. Analysis of this compound extracted from serum of cancer patients, was carried out by I.R., U.V., mass spectrography and nuclear magnetic resonance (N.M.R.) determination. This analysis led us to the conclusion that the compound was a ketone derivative of D3 vitamin: 1-ceto-24-methyl-25-hydroxycholecalciferol, provisionally designated D3C. Enzymatic pathways involved in the biosynthesis of this substance and its possible role in normal and pathological cell division are discussed. 相似文献
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Severe hemorrhagic radiation proctitis advancing to gradual cessation with hyperbaric oxygen 总被引:3,自引:0,他引:3
Dr. Jacky Charneau MD Gilles Bouachour MD Bruno Person MD Pascal Burtin MD Jean Ronceray MD Jean Boyer MD 《Digestive diseases and sciences》1991,36(3):373-375
Summary We report a case of a male patient suffering from a severe hemorrhagic radiation proctitis which gradually ceased with hyperbaric oxygen. We discuss the mechanisms of chronic radiation injury and the effect of the hyperbaric oxygen. This therapy is proposed as an alternative to surgical intervention for this abnormality. 相似文献
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This single (examiner) blind, randomized, 4-week study compared the safety and efficacy of a new electric toothbrush (experimental) regarding plaque removal and reducing gingivitis with two other brushes, an electric brush (control electric) and a manual toothbrush (control hand). Ninety-six subjects with 1) a minimum of 15 suitable teeth in acceptable occlusion; 2) a minimum gingivitis score of 0.9; and 3) a minimum plaque score of 1.8 were entered into the study. The subjects were randomly assigned to one of 3 groups: a control hand group (31 subjects), an experimental group (32 subjects), and a control electric group (33 subjects). Device use instructions were given according to the manufacturer's recommendations. Two examiners separately determined either gingival scores or plaque scores at baseline and 4 weeks. In regard to gingivitis, use of all 3 brushes for the study period showed statistically significant improvements in gingivitis scores (P values less than 0.01) within each of the 3 groups. Between group analyses of covariance showed that of the 3 groups, the control hand group improvement was better than both the experimental and the control electric groups (P less than 0.05). When interproximal gingivitis scores were analyzed separately, similar improvements were noted. Regarding effectiveness of plaque removal during a single brushing event at the initial and final visits, each of the 3 brushes was effective in reducing plaque for every tooth surface scored (P values less than 0.01). However, between group analyses of covariances showed that the experimental group was better than the other two (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Berbaum KS; el-Khoury GY; Franken EA Jr; Kathol M; Montgomery WJ; Hesson W 《Radiology》1988,168(2):507-511
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information. 相似文献
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J-L Stievenart EA Cabanis P Menard J Knoplioch A Lopez J Tamraz M-T Iba-Zizen B Philippe G Prevost J-C Bertrand 《Surgical and radiologic anatomy : SRA》1993,15(1):47-54
Summary In view of the variety of 3D representation techniques, a clinical study was carried out in order to evaluate their respective usefulness. It appears that a single technique cannot be claimed to be valid for all clinical situations and that a combination of representations brings more relevant information. Among the different techniques a clear delineation must be established between those which allow the accurate definition of landmarks (multiplanar reformation, surface representation), and those which do not (integral shading, reconstructed radiology). The main point is the possibility to recognize anatomical landmarks on these latter modes and to choose oblique cut planes in relation to them. Visualization quality is strongly dependent upon the acquisition protocol which must provide a spatial resolution as isotropic as possible.
Une revue de différents modes de visualisation en haute résolution d'un objet volumique avec des applications
Résumé Face à la variété des techniques de représentation 3D une étude clinique a été conduite pour évaluer leurs utilités respectives. Il apparait qu'une technique unique ne peut pas convenir à toutes les situations cliniques et qu'une combinaison de différents modes de présentation apporte une information plus pertinente. Parmi les différentes techniques une distinction claire doit être établie entre celles qui autorisent la prise de repères précis (reformatage multiplanaire, représentation de surface), et celles qui ne le permettent pas (ombrage intégral, radiologie reconstruite). Le point principal est la possibilité de reconnaître des repères anatomiques sur ces derniers modes et de choisir des plans de coupe en relation avec eux. La qualité de la visualisation dépend étroitement du protocole d'acquisition qui doit fournir une résolution aussi isotrope que possible.相似文献