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The effect of cibenzoline succinate, a new antiarrhythmic agent, was studied on insulin secretion in rats. Experiments were performed both in vivo and in vitro using two preparations: the isolated perfused pancreas and isolated islets. In anaesthetized rats, cibenzoline was able to increase plasma insulin levels and to reduce glycaemia. These effects were observed at 1 mg/kg i.v. in fed rats and at 3 mg/kg i.v. in fasted rats. In the isolated pancreas perfused in the presence of a slightly stimulating glucose concentration (8.3 mM), cibenzoline (2 and 6 microM) elicited a progressive and sustained insulin response in a concentration-dependent manner. In the presence of a non-stimulating glucose concentration (4.2 mM), cibenzoline was ineffective at 2 microM and slightly increased basal insulin release at 6 microM. In isolated islets incubated with 8.3 mM glucose, cibenzoline (6 and 20 microM) caused a concentration-dependent stimulation of insulin release. It is concluded that cibenzoline stimulates insulin secretion by a direct action on pancreatic B cells in rats.  相似文献   
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Résumé Un grand nombre de prothèses du coude sont actuellement disponibles, beaucoup de critères les opposent les unes aux autres. Après les premières prothèses à charnière contrainte, les prothèses semicontraintes et plus récemment les prothèses à glissement se sont imposées. La prothèse à glissement GUEPAR se situe dans l'évolution récente des implants du coude. Nous rapportons ici les résultats des trente-neuf premières arthroplasties réalisées au sein du Guepar de 1986 à 1991, sur 33 coudes rhumato?des, 4 destructions post-traumatiques, 1 spondylarthrite ankylosante et 1 arthrose sur chondrocalcinose.
The Guepar total elbow arthroplasty
Summary The Guepar total elbow replacement is a low friction, minimally constrained gliding prosthesis. The humeral and ulnar components are of metal with intramedullary stems, which are cemented. There is a sigmoid shaped, high density polyethylene interposition bearing. The authors have used the prosthesis in 33 patients with rheumatoid arthritis, 4 with post-traumatic problems, one with chondrocalcinosis and another with degenerative changes of uncertain aetiology. In the patients with rheumatoid arthritis, one sustaine a posterior dislocation and two suffered deep infection. In the remaining 30, the overall results were good at an average review of 32 months. The mean range of movement had increased by 31° and pain was absent in 28 elbows. In the management of rheumatoid arthritis total elbow arthroplasty must be part of an overall plan of treatment. Severe involvement of the wrist and shoulder must be dealt with before elbow replacement is considered.


Nous remercions Mr J. H. Aubriot, M. Condamine, A Deburge, B Lassale, T Le Balc'h, J. Y. Nordin et J Witvoet, membres du GUEPAR (Groupe pour l'utilisation et l'étude des prothèses articulaires) de nous avoir donné leurs observations  相似文献   
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OBJECTIVES: Little information is available to incoming students in pediatrics residency programs on the experiences of past residents. The objective of this study was to investigate the pediatrics training programs and determine the professional outcomes of graduating residents between 1990 and 2000 in the Western Interregion. POPULATION AND METHODS: Questionnaires were distributed to the 187 medical students enrolled in pediatrics residency programs between 1990 and 2000 in the six university hospital centers of the Western Interregion. The questions concerned the details of training, the modes of residency positions, and current professional and personal situations. One hundred and sixty-five (88%) individuals responded. RESULTS: Seventy-seven percent of the practicing pediatricians stated that the training they had received during residency was adapted to their current practice. This percentage was higher for hospital staff physicians (82%) than for the physicians in private practice (50%) or those with salaried positions outside the hospital system (58%). One hundred and twenty-four had either completed post-residency training (97) or were doing so (27) at the time of the survey. All but one were professionally active, three quarters of them in hospitals and, of these, most were in the hospitals where they had trained. Eighty-six percent of the practicing pediatricians said they were satisfied with their professional work and 73% said they were satisfied with their personal lives. CONCLUSION: These results support the current reflection on reforming the residency training program in pediatrics, especially with regard to its prolongation and the diversification of the training options to take into account the individual student's professional orientation.  相似文献   
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We retrospectively studied a series of 385 carotid endarterectomies performed either under general anesthesia (242) or under local anesthesia (145) to compare the peri-operative mortality and morbidity rate and to identify factors which may influence the choice of anesthesia. The rate of transient ischaemic attacks (TIA), stroke, death, combined mortality, severe neurological and cardiac morbidity were not statistically different. Under general anesthesia, more shunts were inserted (17% versus 7%, p less than 0.05) and more myocardial infarctions occurred (5% versus 0%, p less than 0.05). However, more strokes due to technical imperfection were seen under regional anesthesia. We concluded that regional anesthesia is more appropriate in patients with coronary artery disease and in patients at risk of intolerance to cross clamping. General anesthesia is more appropriate in poorly cooperative patients or in those with unfavorable operative conditions.  相似文献   
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This work describes the synthesis of new amphiphilic perfluorohexyl- and perfluorooctyl-propanethio-beta-cyclodextrins and the comparison of the ability of these molecules and alkyl analogue, nonanethio-beta-cyclodextrin to form nanospheres. Nanospheres were prepared using nanoprecipitation method (perfluoroalkylthio-beta-cyclodextrin in THF [0.11 x 10(-3)M], stirring rate 700rpm, addition of aqueous phase at 64 degrees C into organic phase at 50 degrees C). They were characterised by Photon Correlation Spectroscopy (PCS) and by electron microscopy (SEM and cryo-TEM). The nanospheres prepared from these new beta-cyclodextrin derivatives have an average size of 260nm, and appear to be spherical in cryo-TEM images. Whereas alkyl analogue forms polydisperse aggregates with sizes in the range 60-350nm.  相似文献   
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There is an inverse relationship between Mg balance and the ratio ionized Mg/total Mg in serum or plasma: in Mg excess, the ratio is decreased and in Mg deficiency the ratio is increased. It works as if a subtle homeostasic compensatory reaction modified the proportion of the most biologically active fraction of blood Mg in order to reduce the effects of Mg imbalance. Easy, available and unexpensive, the evaluation of total Mg in plasma or serum appears as a better marker than ionized Mg in Mg imbalance: it should be priviledged as the initial investigation in clinical practice.  相似文献   
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