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Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Its diagnosis is based on clinical examination, including ultrasound, laboratory analyses, as well as determination of the tumour marker alpha-fetoprotein (AFP). If evidence for HCC is present, further imaging techniques (CT, MRI), and, if required, histopathological examination are necessary. The most important risk factors are chronic hepatitis B, C, and D, metabolic liver diseases, especially hereditary hemochromatosis, toxins (alcohol, aflatoxin) and states of insulin resistance. This knowledge provides us with strategies for HCC prevention that are of great clinical significance, in particular because, in spite of recent advances, the current therapeutic options for most patients remain very limited.  相似文献   
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A nationwide evaluation of multiple congenital abnormalities in Hungary   总被引:1,自引:0,他引:1  
A population-based study of 7,049 index patients with multiple congenital abnormalities (MCA) born in Hungary during 1973-1982 was organized by the Hungarian Center for Congenital Anomaly Control. All clinically recognized syndromes and associations which were submitted (2,049) were accepted without any further follow-up. New or supplementary information was requested in the case of unspecified MCA (320). A copy of detailed necropsy records was requested from pathologists in lethal cases (2,022). Following these steps, apparent but not true instances of MCA were excluded (399), and an attempt was made to assign as many of the remainder as possible in 17 well-delineated MCA entities (900). The living index patients with severe MCA were referred where possible to the regional centers for evaluation (864). One hundred and seventy entities were identified, and seven cases were excluded as not representing MCA. In the so-called 3,393 unidentified cases for which no diagnosis was possible, the component abnormalities were tabulated according to their number. The final count was 6,643 cases with MCA, which is equivalent to a birth prevalence of 4.0 per 1,000 total births, and to 10% of recorded cases with congenital anomalies. As a result of this program the proportion of recognized syndromes and associations among children with MCA increased from 29% to 47%. The accuracy of diagnoses has improved, e.g., the occurrence of unspecified cases decreased from 4.5% to 2%. As a result of this study, the number of chromosomal (1,700), Mendelian (557), and teratogenic (104) syndromes and associations (758) was considerably greater than the initial notifications indicated.  相似文献   
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Sur l'initiative de la Direction et de l'ingénieur biomédical, une première évaluation des pratiques de programmation a été conduite au sein du centre hospitalo-universitaire de Nîmes avec l'ensemble des acteurs concernés. L'autoévaluation se poursuit avec l'inclusion de cinq CHU de référence. Les pratiques observées permettent l'élaboration d'un questionnaire. Le questionnaire est structuré selon les phases traditionnelles du processus de programmation : état de connaissance du patrimoine ; recueil des besoins ; analyse ; décision ; réalisation du programme. Par phases, plusieurs questions fermées explorent les variables. Trente établissements sont inclus. Les résultats de l'enquête et les données initialement collectées dressent un panorama des pratiques de programmation des investissements biomédicaux en établissements de soins publics. Le résultat obtenu semble être la première étape de l'élaboration d'un référentiel professionnel. L'ensemble a permis d'étayer une refonte concrète de nos pratiques de programmation.With the initiative of the top management and the biomedical engineer, the first-assessment of the biomedical pratical programmation of the Nîmes University Hospital Center (CHU), has been led by representatives of different departments of the center. The auditing has been done with five members of the Nîmes University Hospital Center (CHU). The practices that observed have helped to create a survey. This survey is structured according to the usual steps of a programmation: statement of properties, collection of needs, analysis, decision, and realisation of the programmation. By groups, several closed questions process the variables. Thirty establishments are taken into account. The results of the study and data initially collected show an array of the practises used for the programming of the biomedical investments into public healthcare establishments. The obtained result seems to be the first stage of the elaboration of a professional reference. The whole has enabled to support a change in the uses of the Nîmes University Hospital Centre (CHU).  相似文献   
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A valine to isoleucine mutation at residue 180 was identified in a French patient with Creutzfeldt-Jakob disease (CJD). The mutation is located in the close vicinity of one of the two N-glycosylation sites of the cellular prion protein (PrPC). Western blot analysis revealed accumulation in the brain of the pathogenic proteinase K-resistant PrP (PrPSc) isoform with the notable absence of the diglycosylated band. The mutant protein expressed in CHO cells was correctly glycosylated, suggesting that the atypical glycosylation pattern of PrPSc was not due to the mutation at position 180. These results suggest that the diglycosylated form of the mutant PrP180I prevents its conversion into the pathogenic mutant form PrPSc180I, supporting a central role of N-linked glycan chains in the PrP conversion process.  相似文献   
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The quantification of a BNCT 10B-carrier, L-p-boronophenylalanine-fructose complex (BPA-F), was evaluated using 1H magnetic resonance spectroscopy (1H MRS) with phantoms at 1.5 and 3.0 T. For proper quantification, relaxation times T1 and T2 are needed. While T1 is relatively easy to determine, the determination of T2 of a coupled spin system of aromatic protons of BPA is not straightforward with standard MRS sequences. In addition, an uncoupled concentration reference for aromatic protons of BPA must be used with caution. In order to determine T2, the response of an aromatic proton spin system to the MRS sequence PRESS with various echo times was calculated and the product of the response curve with exponential decay was fitted to the measured intensities. Furthermore, the response curve can be used to correct the intensities, when an uncoupled resonance is used as a concentration reference. BPA was quantified using both phantom replacement and internal water referencing methods with accuracies of +/- 5% and +/- 15%. Our phantom results suggest that in vivo studies on BPA concentration determination will be feasible.  相似文献   
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