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OBJECTIVE: To examine 6 years of practice characteristics data of Fellows of the American Academy of Pediatrics (AAP), focusing on sex differences for specialty area, primary activity, practice setting, and practice location. METHODS: We analyzed data from 19 Periodic Surveys that were fielded between 1987 and 1992. The Periodic Survey is used to survey AAP members regularly about current issues in pediatric practice. There are no duplicate respondents in these analyses of the first 19 Periodic Surveys. We collapsed the 19 surveys into the years in which they were fielded, and analyzed sex differences for each of the 6 years. In addition, we ran logistic regressions on several questions, including all 16 868 respondents, to examine how the characteristics of the specialty have been affected by the increase in the number of female pediatricians, controlling for survey year, age of respondents, and specialty area practiced. RESULTS: The proportion of nonresident AAP members who are female has grown throughout the 6 years; in 1987, 26.9% were female, and in 1992, 36.4% were female. For 5 of the 6 years there were sex differences in specialty area, usually concerning pediatric subspecialties. Substantial sex differences occurred in primary activity, in which each year women were more likely than men to be salaried. Men were more often in group practices, whereas women were generally more likely to practice in hospitals or clinics. Logistic regression demonstrated that there are sex differences in practice characteristics across time, but there is also a substantial change in practice characteristics accountable to survey year, eg, a pediatrician of either sex was 75% more likely to be salaried in 1992 than in 1987. CONCLUSIONS: Throughout the 6-year period, AAP members became increasingly more likely to practice general pediatrics, to be salaried, and to be younger-all effects independent of sex, all effects stronger for females. Rapid transformations in the health care system will likely reduce current sex differences in practice characteristics of the future.  相似文献   
84.
We present a case of unanticipated postoperative apnoea in a patient with associated medical illness to illustrate the diagnostic difficulty that can arise in the detection and subsequent management of mivacurium apnoea. A high index of suspicion is essential in the presence of concomitant medical conditions that may cause prolonged apnoea. To our knowledge, no report exists documenting the unanticipated occurrence of mivacurium apnoea in a patient with previously undiagnosed pseudoCholinesterase deficiency and concomitant medical illness who has previously undergone ‘balanced’ general anaesthesia.  相似文献   
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CT-guided transsternal core biopsy of anterior mediastinal masses   总被引:5,自引:0,他引:5  
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87.
BACKGROUND: Onychomycosis is a rare disorder in children. Few studies exist on the incidence or prevalence of onychomycosis in children. OBJECTIVE: To examine the epidemiology of childhood onychomycosis in Iceland during the period 1982-2000. METHODS: Results from all mycological samples taken from children in Iceland from 1982 to 2000 were examined. Information about the requesting physician, unique social security number, date of birth, sex, results of culture and microscopy were registered. Growth of a dermatophyte was taken as an indication of a case of onychomycosis. RESULTS: During the period 1982-2000 a total of 493 samples from 408 Icelandic children, aged 0-17 years, were examined. Dermatophytes were cultured from 148 (30.0%) samples. During the period 1982-85, the mean annual incidence of positive cultures was 1.65 per 100,000, increasing to 21.30 per 100,000 for the years 1996-2000. Trichophyton rubrum was the dominating organism and was found in 102/148 cases positive for the growth of a dermatophyte. The incidence of positive dermatophyte cultures increased with age and was found in eight children aged 0-4, and in 57 children aged 10-14 years. CONCLUSION: Onychomycosis is rare in children, but increases with age. It seems that onychomycosis increased during the study period, but it is not clear if this was due to a true increase in the prevalence of onychomycosis or an increased awareness of onychomycosis, or both.  相似文献   
88.
Summary Techniques to reinforce a vessel wall without occluding its lumen are being studied. In pilot experiments the intimal surface along a short segment of vein was coated with plastic by injecting liquid silicone rubber into a vessel, spreading the material along the vessel with a balloon catheter, allowing polymerization and then removing the catheter. In 17 experiments in the iliac vein of rabbits, successful coating was obtained in 5. If perfected, these techniques might be applicable to treating some aneurysms or arteriosclerotic plaques.  相似文献   
89.
S-carboxymethyl-L-cysteine (carbocysteine) improves the visco-elastic properties of bronchial mucus in vivo, possibly as a result of an increase in the relative proportions of sialomucins in bronchial mucus. Carbocysteine was therefore studied in vitro and ex vivo in both normal and bronchitic rats on pulmonary sialyl transferase, responsible for the addition of sialic acid to mucus glycoproteins. Bronchitis was induced in male Sprague-Dawley rats by repeated exposure to sulphur dioxide for two weeks. During this time they received either 500 mg kg-1 day-1 carbocysteine or its vehicle by the oral route. Rats not being exposed to SO2 received the same treatment. The animals were then killed, and subcellular fractions prepared by differential centrifugation of lung homogenates. Sialyl transferase was assayed using CMP-14C sialic acid as substrate and desialysed fetuin as exogenous acceptor. Enzyme activity was located in both the (Golgi-containing) 10,000 g and 100,000 g pellets with minor activity in the cytosolic supernatants. When tested in vitro between 10(-6) and 10(-3) M, carbocysteine had no effect on sialyl transferase activity in microsomes taken from healthy or bronchitis rats. Repeated administration of carbocysteine was without effect on the sialyl transferase activity in 10,000 g pellets taken from healthy rats. However, in bronchitic rats there was a small but statistically significant (P less than 0.05) increase in enzymic activity in the treated group compared to the animals receiving the vehicle. There was no difference in the activity of the microsomal enzyme compared to vehicle-treated controls in either healthy or bronchitic rats. We conclude that it is possible that an increase in sialyl transferase activity in a Golgi-containing fraction of bronchitic lungs could explain the relative increase in sialomucins in bronchitic subjects.  相似文献   
90.
Undifferentiated (embryonal) sarcoma (UES) is an uncommon malignant mesenchymal hepatic tumor that occurs in older children and young adults. Fourteen cases are correlated with radiologic and pathologic findings. Radiologic findings reflect the spectrum of solid to cystic appearances observed in the gross specimens. Sonography typically demonstrates a large mass that may be predominantly solid with many small anechoic spaces or may be cystic. Computed tomography reveals a hypodense mass with hyperdense septa of variable thickness and a dense peripheral rim corresponding to the fibrous pseudocapsule of the tumor. Angiographically, UES is usually hypovascular with tumoral vessels, although hypervascular and avascular patterns occur. Prognosis of UES is poor, with a median survival of less than 1 year. Radiologists should be familiar with this malignant tumor since it may present as a large cystic hepatic mass, suggestive of a benign lesion.  相似文献   
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