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61.
This clinical research plan was designed to evaluate the predictable and current developments, growth, and stability of the economic status of part-time or full-time African-American practicing surgeons. In many communities throughout the United States, the economic successes of certified or experienced black surgical specialists are inhibited or modified by mistrust, jealousy, professional disengagements, prejudices, and self-hatred by black and white physicians and lay African Americans. Nevertheless, there are subtle and overt evidences of increasing satisfactory and above average associative interprofessional relationships between African-American physicians and surgical specialists. One hundred African-American surgical specialists from thirty-four communities in the United States were interviewed at periodic intervals over a period of three decades. Recommendations for improvements and changes are presented. 相似文献
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BH Yoon R Romero JK Jun KH Park JD Park F Ghezzi BI Kim 《Canadian Metallurgical Quarterly》1997,177(4):825-830
OBJECTIVE: Our purpose was to test the hypothesis that neonates who develop bronchopulmonary dysplasia have higher amniotic fluid concentrations of proinflammatory cytokines than those who do not develop bronchopulmonary dysplasia. STUDY DESIGN: The relationship between amniotic fluid concentrations of interleukin-6, tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-8 and the occurrence of bronchopulmonary dysplasia in the neonate was examined in 69 patients who were delivered of preterm neonates (< or = 33 weeks) within 5 days of amniocentesis. Cytokines were measured by specific immunoassays. RESULTS: Bronchopulmonary dysplasia was diagnosed in 19% (13/69) of newborns. Median amniotic fluid concentrations of interleukin-6, tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-8 concentrations were significantly higher in mothers whose infants had bronchopulmonary dysplasia than in mothers whose infants did not have bronchopulmonary dysplasia (p < 0.05 for each). Neonates who had bronchopulmonary dysplasia were delivered at earlier gestational ages and had lower birth weights than those without bronchopulmonary dysplasia. The differences in median amniotic fluid interleukin-6, interleukin-1 beta, and interleukin-8 between these two groups remained significant after we adjusted for the effect of gestational age at birth (p < 0.05 for each). CONCLUSIONS: (1) Antenatal exposure to proinflammatory cytokines is a risk factor for the development of bronchopulmonary dysplasia; (2) the injury responsible for bronchopulmonary dysplasia in a subset of neonates may begin before birth. 相似文献
64.
JM Rogers M Usui BH KenKnight RE Ideker WM Smith 《Canadian Metallurgical Quarterly》1997,25(5):749-760
We have developed a method for quantifying the complexity of activation patterns observed during ventricular fibrillation (VF) that is based on our previously reported methodology for decomposing epicardial mapping data into a set of isolated wavefronts. One-half second datasets are acquired from a 21 x 24 array of unipolar electrodes (1 mm spacing), and the wavefronts are isolated. A correlation technique is used to compute the similarity between all possible pairs of the isolated wavefronts. From these data, the wavefronts are sorted into clusters, each of which represents a recurring wavefront morphology. We define multiplicity (M) as the number of clusters needed to account for 90% of the total activations in the VF episode. M measures the complexity of the rhythm. In repetitive patterns (e.g., sinus rhythm), M = 1, indicating that the same morphology repeatedly activates the mapped region. Typically, in VF, M > 1, with larger numbers representing more complex, disorganized patterns. As an example, we computed M at 5, 10, 15, and 20 sec after electrical induction of VF in six pigs. M decreased significantly (p < 0.001), suggesting increasing organization during this period. 相似文献
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WA Bleyer H Tejeda SB Murphy LL Robison JA Ross BH Pollock RK Severson OW Brawley MA Smith RS Ungerleider 《Canadian Metallurgical Quarterly》1997,21(6):366-373
PURPOSE: To determine whether adolescents with cancer, who in comparison to younger patients have a higher cancer incidence and lower mortality reduction, have equal access to national cancer clinical trials. METHODS: The ethnic/racial distribution of 29,859 subjects < 20 years of age entered onto National Cancer Institute-sponsored clinical trials between January 1, 1991, and June 30, 1994, was compared with the expected distribution of patients of the same age in the United States. RESULTS: The Children's Cancer Group and Pediatric Oncology Group had 29,134 (97.6%) of the total study entries among < 20-year-old subjects during the 3.5 years of surveillance. The adult cooperative groups accounted for < 3% of the clinical trials entries in the 15-19-year age range. When analyzed nationally by region, the under-representation of the older adolescent subjects was universal. From other analyses, the two pediatric cooperative groups were estimated to have registered > 94% of the children < 15 years of age who were expected to have been diagnosed to have cancer, but only 21% of the cancer patients in the 15-19-year age group. CONCLUSIONS: The national pediatric cancer cooperative groups allow the majority of American children < 15 years of age and their families equal opportunity to access clinical cancer trials, regardless of race or ethnicity. Among patients 15-19 years of age, however, > 75% are not being enrolled by any cooperative group sponsored by the National Cancer Institute. Thus, older adolescents are disadvantaged with respect to access to the national clinical trials, regardless of their race or ethnicity. 相似文献
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EO Olapade-Olaopa RN Morley CJ Carter BH Walmsley 《Canadian Metallurgical Quarterly》1997,11(6):350-351
Lower genito-urinary problems are part of the polyneuropathy of diabetes. Cystopathy affects 40%-85% of diabetic patients, although less than half are symptomatic. We report on a 42-year-old patient who was not known to be diabetic, and who presented to the urologists with primary acute urinary retention. His underlaying disease was detected by a test for random blood glucose. More common causes were excluded with careful clinical and radiological examinations. He was managed with insulin and self-catheterization. Diabetes should be considered as a differential diagnosis in relatively young men who present with unexplained acute urinary retention. 相似文献
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BH Güven? T Salman B Tokar E Sürmen T AltuG A Celik 《Canadian Metallurgical Quarterly》1997,12(5-6):367-369
Fetal tissue transplantation has gathered considerable interest among researchers dealing with organ transplantation. A large number of studies concerning fetal intestinal transplantation have been published in the past 2 decades, almost all of them aiming to determine the feasibility of a properly functioning fetal transplant in continuity with the host's own enteral system. This study was designed to determine the absorptive capacity of the neogut in vivo, without anastomosing the transplant to the host's intestine, and to evaluate its use as an accessory enteral segment. Intestinal segments taken from Wistar albino fetuses were transplanted subcutaneously into the abdominal wall of 20 Sprague-Dawley rats. Immunosuppression was maintained by daily cyclosporin A (Cy A) 10 mg/kg injections s.c. and evaluated by determination of serum Cy A level and T-helper/T-suppressor cell ratio. The neogut was converted into a Thiry-Vella loop 2 weeks after transplantation. A test solution composed of 20% glucose and Trophamine was perfused via the stomas; glucose and amino acid absorption gradients were calculated. The gamma-glutamyl transferase (GGT) activity and mitotic index of the neogut were determined. Results were compared to those obtained from the host. There was no significant difference (P > 0.05) in glucose absorption between the neogut and the host tissue. Amino acid absorption and specific GGT activity were significantly less (P < 0.01) in the neogut. There was no significant difference (P > 0.05) between neogut and host intestine in mitotic index. Our data support the idea of using a transplanted fetal intestinal segment as an accessory feeding route. 相似文献