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1.
We performed the serum IgA antiendomysium antibody (EmA) assay by indirect immunofluorescence on human umbilical cord sections in 86 subjects with celiac disease, in 187 first-degree relatives of such patients, and in a control group of 68 unrelated subjects, to investigate the suitability of the method in the screening of populations at risk of gluten sensitivity. Conventional EmA assay using monkey esophagus sections was performed in parallel experiments. The results obtained showed a perfpect correlation between the two methods. All the celiac patients and none of the controls were positive for EmA. EmA positivity was also observed in 11 apparently healthy relatives: intestinal biopsy performed in five of them invariably showed villous atrophy and increase of mucosal lymphocytes. Taking into account the low cost of EmA assay on human umbilical cord, especially when compared to monkey esophagus sections, the method is probably suitable and effective in identifying latent, asymptomatic gluten sensitivity in at-risk populations.  相似文献   
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The need for resuscitation of a distressed newborn in delivery room is more and more easily predictable. The two principal reasons are improvement of obstetrical survey and best perinatal regionalisation. Perinatal asphyxia and premature labour, especially before 32 weeks of gestational age, are the more frequent situation needing resuscitation at birth. A good survey of pregnancy and labor, verification of availability and efficiency of care devices and material in the delivery room are essential. In all guidelines respiratory resuscitation is today the priority in the first minutes. Non invasive positive pressure ventilation and early use of exogenous surfactant are the recent advances for the care of very premature baby in delivery room. Having a neonatal ventilator and pulse oximetry monitoring is recommended and can improve results. For the pregnant woman and the baby, maternal transfer if no contra-indications exist and when it is possible, is preferred to postnatal transportation in case of very premature labor or high risk pregnancy. In all the other situations neonatal transport must be strictly organised and realised by well-trained pediatric team, with adapted material and in the best conditions for security and comfort. The goal is to prevent any rupture until arrival in the referring neonatal intensive car unit.  相似文献   
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The development of in vitro blood tests that measure the delayed hypersensitivity reaction developed after contact with Mycobacterium tuberculosis will change progressively the diagnosis of M. tuberculosis infection. These blood assays (Quantiferon TB Gold, Cellestis, Australia; T-SPOT.TB, Oxford Immunotec, United Kingdom) use specific, complex M. tuberculosis antigens (ESAT-6 and CFP-10), whereas the intra-dermal Mantoux test is done with tuberculin, a complex mixture of more than 200 antigens. ESAT-6 and CFP-10 are absent from all the BCG vaccine strains used throughout the world. Significant improvement in the specificity with equivalent or increased sensitivity of the in vitro tests compared to the Mantoux test will lead eventually to replacement of the latter.  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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In order to verify if H2O2 affects platelet function, platelet-rich plasma and human washed platelets were incubated with subthreshold concentrations (STC) of collagen or arachidonic acid or ADP and/or with 75-150 microM H2O2. While H2O2 alone did not affect platelet aggregation, it amplified platelet aggregation response in samples stimulated with STC of arachidonic acid and collagen but not in samples stimulated with STC of ADP. When platelets were preventively treated with aspirin, a cyclooxygenase inhibitor, the platelet activation by H2O2 was not observed. Thromboxane A2 (TxA2) was not produced by human washed platelets stimulated with STC of arachidonic acid, collagen or by H2O2 alone. On the contrary, when STC of agonists were tested on platelets supplemented with H2O2 an evident TxA2 production was seen. This effect was prevented by aspirin pretreatment or by the addition of catalase, an enzyme which destroys H2O2. This study suggests that H2O2 triggers the activation of platelets exposed to STC of collagen and arachidonic acid, via the cyclooxygenase pathway.  相似文献   
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Right ventricular function is frequently abnormal in patients with systemic sclerosis, but whether this is related to pulmonary vascular complications of the disease is unclear. Standard echocardiography with tissue Doppler imaging was performed at rest and during exercise for the study of right ventricular function and pulmonary circulation in 25 consecutive systemic sclerosis patients and in 13 age-matched healthy controls. When compared with the controls, the patients had no difference in systolic right ventricular pressure gradient, but a decreased pulmonary flow acceleration time, and increased right ventricular free wall thickness and end-diastolic dimensions. At the tricuspid annulus, the E maximal velocity was decreased (8.9 +/- 4 versus 11.7 +/- 2.3 cm.s(-1)) and the isovolumic relaxation time corrected to RR interval was increased (6.5 +/- 2.9 versus 4.5 +/- 2.5%). The tissue Doppler imaging profile at the mitral annulus was similar in both groups. At exercise, 18 patients had a decreased maximum workload and cardiac output, no change in systolic right ventricular pressure gradient, but an increase in the slope of pulmonary artery pressure/flow relationships. These results suggest that patients with systemic sclerosis may present with latent pulmonary hypertension as a likely cause of right ventricular diastolic dysfunction, as revealed by stress echocardiography and tissue Doppler imaging.  相似文献   
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