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1.
We are presenting a computer program requiring the use of an Expert System accessible by Minitel, intended for patients with arterial disease and their attending physician. The objective is not to make a diagnosis, but to train the patients in applying health measures to the handling and prevention of his/her disease. While remaining anonymous, the patient may consult the program at home, without any time constraint. Only the patient's physician can authorize him/her to have access to the program. The Expert System may adjust the answers to the patients according to the past history and recent data. Contrary to a computer program, new knowledge does not impair the functioning of the system. The physician has access to simplified modules regarding his patient, and specific modules regarding the treatment. Such a system would help general practitioners in following his patient and would facilitate the Doctor-Patient relationship during consultations.  相似文献   
2.
The concept of treatment-resistant schizophrenia cannot be defined as this of resistant depression: schizophrenia is a long-term illness; its evolution is almost always influenced by neuroleptics--but complete recovery is rare. French psychiatry tends to use clinical-empirical criteria, while english speaking studies prefer quantitative criteria, by extended use of clinical and psycho-social scales. The definition of resistant schizophrenia by Kane et al. is a typical example of this method of work. We propose to overview the limits of neuroleptics efficiency in schizophrenia from three groups of studies: a) The effects of maintenance therapy: 24 studies of the last twenty years show that 2/3 of schizophrenics under neuroleptics maintain their remission over one or two years, opposed to less than 1/3 of those who discontinue their treatment. These data seem to be independant from the method of the study, the choice of the neuroleptic drug, the dose and the way of administration (per os or depot treatment). b) A second group of studies tries to define the clinical characteristics of treatment-resistant schizophrenia. French psychiatry uses an empirical graduation of neuroleptics clinical efficiency: these drugs are more effective on hallucinations than on delusional ideas--they are more effective on recent and acute hallucinations and delusions than on those of which course is chronic. Other studies specify predictive factors of poor response to neuroleptics, as few affective symptoms and presence of negative symptoms--a controversed factor. c) Not clinical factors of poor neuroleptics efficiency in schizophrenia begin to be studied.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
This study validates a new quantitative myocardial perfusion SPECT software. METHODS: The processing starts with the extraction of the morphologic skeleton of the left ventricular myocardium from reconstructed transverse sections. Fuzzy logic is used to decide whether a pixel belongs to the myocardium and any perfusion defect is filled according to a truncated bullet model. The resulting image is partitioned in 18 isovolumetric sectors. Sex-matched normal limits, criteria of abnormality for rest (201)Tl and (99m)Tc-labeled perfusion tracers, reproducibility studies, and detection of coronary artery disease were developed and validated in an overall population of 343 patients. The sex- and tracer-matched means and SDs of a normal response were calculated in 93 male and 93 female patients with a <5% likelihood of coronary artery disease. Reproducibility measurements and assignment of different sectors of the myocardium to a specific coronary were performed from data collected in 49 and 60 patients, respectively. The accuracy of the detection of a coronary artery occlusion was assessed in 48 patients who also underwent coronary angiography. RESULTS: The intra- and interoperator reproducibility of the sectorial activity was high with a linear regression coefficient of 0.97 and a SD of the difference measurement at 4.4% and 3.8%, respectively. Overall sensitivity and specificity for the detection of occluded coronary artery were 90% and 80%, respectively. For the detection of left anterior descending, left circumflex, and right artery coronary occlusion, sensitivity was 92%, 75%, and 92.5%, respectively, and specificity was 75%, 78%, and 90%, respectively. CONCLUSION: The new quantitative myocardial perfusion SPECT software appears to be a very helpful program for the objective analysis of perfusion tracer distribution in myocardial SPECT and a very accurate tool in the detection and localization of coronary artery occlusion.  相似文献   
4.
Florent  C. 《Acta endoscopica》2002,32(1):445-453
Acta Endoscopica - De nos jours, les patients en prise avec une pathologie d’intensité moyenne à forte en rapport avec l’hyperacidité sont traités de façon...  相似文献   
5.
D Boyd  G Florent  P Kim  M Brattain 《Cancer research》1988,48(11):3112-3116
At present, there is a lack of availability of differentiation markers for colon carcinoma. This may, in part, be a consequence of the diversified function of the normal human colon. This study addresses the possibility that the expression of urokinase and its receptor is inversely related to differentiation in colon carcinoma. Six colon carcinoma cell lines including three well-differentiated (CBS, GEO, FET) and three poorly differentiated ones (HCT116, HCT116b, RKO) were screened for urokinase receptor display and secretion of the plasminogen activator. A radioreceptor assay was used to determine receptor levels. Binding of radioactive urokinase to colon cells was saturable, specific, and time dependent. Cell-bound 125I-labeled protease was unaffected by the presence of epidermal growth factor, low-molecular-weight urokinase, plasminogen, or transferrin. Time course studies revealed that maximum amounts of radioactive tracer were bound in a 30-min period with no change occurring over the course of a 90-min incubation. Scatchard analysis of ligand binding indicated that the well-and poorly differentiated cells could be separated on the basis of receptor display; the aggressive RKO, HCT116, and HCT116b expressed in excess of 10(5) sites per cell, while the more indolent CBS, GEO, and FET possessed less than 1.5 X 10(4) receptors per cell. The colon carcinoma cells were also analyzed for urokinase in the conditioned medium. Low levels of the plasminogen activator (0.8 to 1.3 ng/ml/10(6) cells/72 h) were associated with the more "mature" cells. This was in contrast to the elevated levels of the protease (3.9 to 11.4 ng/ml/10(6) cells/72 h) present in the medium derived from the more aggressive cells (HCT 116, HCT116b, RKO). Thus, secreted urokinase and/or the expression of cellular receptor for the plasminogen activator may provide useful measurements of the degree of undifferentiation of in vitro colon carcinoma.  相似文献   
6.
A glucuro-conjugated carbamate derivative of 5-fluorouracil (5-FU), originally designed as a prodrug for antibody-directed enzyme prodrug therapy (ADEPT) application, has been used for direct in vivo observation of in situ 5-FU generation in two human colon tumors heterotransplanted in nude mice. Because of the very fast elimination of glucuro-conjugated drugs, this observation required intratumoral injection. These tumors, when becoming necrotic, are rich enough in beta-glucuronidase to allow (19)F magnetic resonance spectroscopy monitoring, at the tumor level, of both prodrug elimination and 5-FU liberation without preliminary treatment by a specifically targeted enzyme conjugate. Convenient tumors have been selected by magnetic resonance imaging (MRI) on the basis of a correlative study between MRI and conventional histology. This contribution is the first report evidencing such a direct intra-tumoral conversion of a glucuro-conjugated prodrug into the expected active drug. This method, which should allow overall estimation of the beta-glucuronidase content of tumors, might also be helpful for selecting tumors as specific targets for non-toxic glucuro-conjugated prodrugs without prior treatment with a fusion protein.  相似文献   
7.
Circulating angiotensin-1-converting enzyme (ACE) is a highly heritable trait, and a major component of the genetic variance maps to the region of the ACE gene. The strong effect of the locus, and the interest in ACE as a candidate gene for cardiovascular disorders, has led to extensive investigation of its relationship to the ACE phenotype, providing one of the most complete examples of quantitative trait locus (QTL) analysis in humans. Resequencing of ACE followed by haplotype analysis in families of British and French origin has shown that the genetic variants that are primarily associated with the ACE trait map to an 18 kb interval flanked by two intragenic, ancestral recombination breakpoints. This critical interval contains dozens of ACE-associated variants in Caucasians, but identification of which of these directly influence ACE concentration is ambiguous because of the almost complete linkage disequilibrium in European populations. In a complementary sequencing and genotyping study of individuals from West African families, we show that this population has much greater haplotype diversity across the gene. Through analysis of the contrasting relationships of the trait phenotype with haplotypes that carry different allelic combinations from those observed in Caucasians, we demonstrate that (at least) two major intragenic sites within the critical interval and (at least) one minor promoter site are associated with the ACE quantitative trait through additive effects. These results point to the importance of analysing diverse populations with different gene genealogies in gene-association studies.  相似文献   
8.
Blastic natural killer (NK) cell lymphoma (also termed CD4+CD56+ hematodermic neoplasm) is a recently described entity, with the first case reported in 1994. It was suggested initially that the disease originates from NK cells. Since 1994, single cases and a few small series have been published. In this review, data from the literature and a series of 30 cases from the French and Dutch study groups on cutaneous lymphomas are discussed. The major clinical, histopathologic, and phenotypic aspects of the disease and diagnostic criteria and data suggesting a plasmacytoid dendritic cell origin for the tumor cells are provided.  相似文献   
9.
ObjectivesMeasures on conventional radiography are used to detect, especially in rheumatoid arthritis, upper cervical spine instabilities (CSIs) with the anterior and posterior atlanto-dental intervals (AADI and PADI) measurements. Our objective was to evaluate the diagnostic performance and reliability of AADIs and PADIs extrapolated based on ratios in assessing anterior atlanto-axial subluxation (aAAS) when plain radiographs do not allow the measures.MethodsRadiographies of 119 patients were randomly selected. Two blinded observers performed two measurements of the odontoid sagittal diameter (O), axis body base sagittal diameter (C2), AADI, PADI, Clark station and Ranawat index, and the AADI/O, AADI/C2, PADI/O and PADI/C2 ratios were calculated. The diagnostic value of AADI and PADI extrapolated from the AADI/O, AADI/C2, PADI/O and PADI/C2 ratios was evaluated using ROC curves, with AADI > 2.9 mm used as the gold standard.ResultsAmong the 119 patients, 12 patients had aAAS (AADI > 2.9 mm), 6 of them had severe aAAS (AADI > 8.9 mm and/or a PADI < 14 mm), and 6 patients had vertical AAS (Clarks station = 2 or 3 and/or Ranawat index < 13 mm). The AADI extrapolated from the AADI/O and AADI/C2 ratios has excellent intra- and inter-observer reproducibility. The diagnostic value of the extrapolated AADI was high for aAAS (sensitivity 92%; specificity of 100%) and severe aAAS (sensitivity75%; specificity 100%). The diagnostic value of the extrapolated PADI was good but lower than the diagnostic value of the extrapolated AADI.ConclusionExtrapolated AADI can be used instead AADI to detect aAAS and severe aAAS.  相似文献   
10.
Clinical classifications of neuroleptics constitute a particularity of European clinical psychopharmacology. However, the importance of evaluation scales in American psychiatry may also lead to an "implicit" clinical classification, since these drugs do not have the same effects upon the same patient. The main European classifications are described and some of actual clinic of neuroleptics are criticised, in particular the concepts of sedative, antipsychotic, antidelusional or antihallucinatory action. We have pointed out three clinical actions which should be selected in a present classification of neuroleptics; a) angolytic effect i.e. specific antianxiety action upon psychotic anxiety, often initiating the therapeutic processes; b) psychic reorganization effect that is the resultant, in schizophrenia, of the antiproductive and antideficitary effects; c) thymoleptic effect, i.e. reductive action upon the strength of passionate insistence and vindication in parano?ac disorders.  相似文献   
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