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81.
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
82.
Differential effect of cyclosporin A (CyA) on IgE response: role of CyA-induced suppressor cells 总被引:1,自引:0,他引:1
Administration of cyclosporin A (CyA, 30 mg/kg) for the five days following immunization of Brown Norway rats with DNP14-OVA in alum abolished the primary total and specific IgE response, whereas this treatment had no significant effect on the secondary IgE response. On the contrary, with a single injection of CyA on the day of priming, the secondary IgE response only is abolished. The inhibition of the secondary IgE response could be attributed to the induction by a single dose of CyA of nylon wool-adherent spleen cells, as shown by passive transfer experiments. CyA might thus affect the IgE response variously depending on single or repeated administrations. 相似文献
83.
84.
Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
85.
J P Becquemin E Paris A Valverde F Pluskwa D Mellière 《The Journal of cardiovascular surgery》1991,32(5):592-598
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
86.
Sandrine Péroche Ghania Degobert Jean-Luc Putaux Marie-Geneviève Blanchin Hatem Fessi Hélène Parrot-Lopez 《European journal of pharmaceutics and biopharmaceutics》2005,60(1):123-131
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
87.
88.
Abstract The aim of the present investigation was to study the frequency of pulp revascularization in therapeutically reimplanted incisors as well; is its relationship with the following factors: width of apical foramen, duration of extra-alveolar lime, storage conditions and postoperative administration of antibiotics. Out of 72 immature teeth (width of apical foramen 1.1–5.0 mm) the pulp was revascularized in 13 (18%), while in 88 mature teeth (width of apical foramen 1.0 mm or less) no revascularization occurred. Among parameters tested statistically in immature teeth, a significantly increased frequency of revascularization (p < 0.05) was only found in teeth reimplanted within 45 minutes after avulsion, when compared with teeth reimplanted after a longer extra-alveolar time, and in mandibular incisors when compared with maxillary incisors (p < 0.01). All teeth in which revascularization did not occur exhibited a periapical radiolucency and/or external inflammatory root resorption. 相似文献
89.
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
90.
Véronique Strijckmans Michel Bottlaender Humin Luo Michèle Ottavianil Daniel W. McPherson Christian Loc'h Chantal Fuseau Furn F. Knapp Bernard Mazière 《European journal of nuclear medicine and molecular imaging》1997,24(5):475-482
We studied the potential of three radiobrominated isomers of BrQNP, (Z(-,-)-[76Br]BrQNP,E(-,-)-[76Br]BrQNP andE(-,+)-[76Br]BrQNP), as suitable radioligands for imaging of central muscarinic cholinergic receptors in the human brain. These radioligands were stereospecifically prepared by electrophilic radiobromodestannylation of the respective tributylstannyl precursors using no-carrier-added [76Br]BrNH4 and peracetic acid. Preliminary pharmacological characterizations were determined by biodistribution, autoradiography, competition, displacement and metabolite studies in rats. The (-,-)-configuration presented important specific uptakes in brain muscarinic cholinergic receptor (mAChR)-rich structures and in heart, low metabolization rates and an apparent M2 selectivity. The (-,+)-configuration revealed more rapid clearance, lower uptake, a higher metabolization rate and an apparent M1 selectivity. Reversibility of the binding was confirmed for the three radiotracers. Positron emission tomography in the living baboon brain revealed high and rapid uptake in the brain and accumulation in the mAChR-rich structures studied. At 30 min p.i., theE(-,-)-radiotracer reached a plateau in cortex, pons and thalamus with concentrations of 29%, 24% and 19% ID/l, respectively.Z(-,-)-[76Br]BrQNP also accumulated in these structures, reaching a maximal uptake (27% ID/l) in the cortex 2 h p.i. At 5 min p.i. a plateau (17% ID/l) was only observed in the cortex for theE(-,+)-[76Br]BrQNP; by contrast, the other structures showed slow washout. After 3 weeks, the (-,-)-radiotracers were studied in the same baboon pretreated with dexetimide (1 mg/kg), a well-known muscarinic antagonist. In all the mAChR structures, the highly reduced uptake observed after this preloading step indicates that these radiotracers specifically bind to muscarinic receptors.Z(-,-)-[76Br]BrQNP, which is displaced in higher amounts from M2 mAChR-enriched structures, reveals an M2 affinity. The two isomers having the (-,-)-configuration are potential probes for investigating central muscarinic receptors. The absolute configuration on the acetate chiral centre influences their muscarinic subtype selectivity and thecis-trans isomerism of the vinyl moiety affects their specific fixation. 相似文献