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21.
22.
Abstract: Data from the National Education Longitudinal Study were combined with census data at the zip code level to examine the impact of neighborhood racial and ethnic diversity and consolidated inequality, in addition to individual, family, and school factors, on the likelihood of dropping out of high school. Results indicate that while the effects for diversity and consolidated inequality did not support the stated hypotheses, main effects for family risk and prior academic achievement were significant and in the stated direction. Also, when controlling for individual, family, school, and neighborhood characteristics, African Americans were less likely than White students to drop out of school. Implications for contextual effects research and educational outcomes are discussed. 相似文献
23.
Carol Ball 《Intensive & critical care nursing》2006,22(3):127-129
24.
25.
L Laforest E Van Ganse G Devouassoux S Chretin L Osman G Bauguil Y Pacheco G Chamba 《The European respiratory journal》2006,27(1):42-50
French asthma patients may be supervised by general practitioners (GPs) and/or specialists. Therefore, this study examined asthma management in patients exclusively supervised by specialists (SPE), GPs, (GP) and both (GP+SPE group), and compared the findings. Asthma patients were consecutively recruited in 348 pharmacies. Each patient completed a questionnaire providing data on personal characteristics, asthma management, perception of disease and asthma supervision. Asthma control was measured using the Asthma Control Test. Questionnaires were linked to computerised records of medications which had been dispensed before inclusion in the study. From the 1,256 patients (mean age = 36.1 yrs, 54.3% females), 11.4, 36.6, and 52.0% were placed in the SPE, GP, and GP+SPE groups, respectively. During the previous 4 weeks, most patients in the SPE group were properly controlled (52.2 versus 26.4 and 21.5% in GP and GP+SPE groups, respectively). The SPE group made more use of fixed combinations of long-acting beta agonist and inhaled corticosteroid, while receiving less short-acting beta agonists, antitussives and antibiotics. Striking differences in symptoms and asthma management were observed according to the type of asthma supervision. The current results strongly support the need to improve the management of asthma in primary care, and the coordination of care between general practitioners and specialists. 相似文献
26.
Sonographic features of benign thyroid nodules: interobserver reliability and overlap with malignancy. 总被引:4,自引:0,他引:4
Jeffrey R Wienke Wui K Chong Julia R Fielding Kelly H Zou Carol A Mittelstaedt 《Journal of ultrasound in medicine》2003,22(10):1027-1031
OBJECTIVE: To prospectively determine the sonographic findings of nodular hyperplasia of the thyroid, to compare these with reported findings associated with malignancy, and to assess interobserver reliability. METHODS: Seventy thyroid nodules were scanned, and then biopsies of the nodules were performed under sonographic guidance with fine-needle cytologic analysis; in all cases images were reviewed by 2 experienced radiologists without knowledge of clinical outcome. Findings reported associated with malignancy were specifically assessed. Interobserver agreement between the expert and secondary readers for each finding was calculated by the kappa or weighted kappa statistic and the Fisher exact test of independence. RESULTS: There were 68 benign and 2 malignant nodules in a population of 63 female and 7 male patients. The mean benign nodule size was 2.9 cm; 60% were solid; 54% were hypoechoic; 59% were microlobulated or macrolobulated; 47% had central vascularity; 24% contained calcifications; and 82% were elliptical in shape. There was very good interobserver reliability for the presence of calcium (kappa = 0.91) and good agreement for the presence and location of vascularity (kappa = 0.75) and the amount of cystic components (kappa = 0.62; all P < .01). CONCLUSIONS: Sixty-nine percent of benign nodules had at least 1 finding reported previously as associated with malignancy. The interobserver reliability of the sonographic findings was good to very good for 3 of the 5 findings assessed. 相似文献
27.
Matthew J Matasar Ellen K Ritchie Nathan Consedine Carol Magai Alfred I Neugut 《European journal of cancer prevention》2006,15(4):367-370
Despite significant improvements in the prognosis of acute promyelocytic leukemia brought about by therapeutic advances, understanding of the epidemiology of acute promyelocytic leukemia remains limited. Earlier reports have suggested that Hispanics may have an increased incidence of acute promyelocytic leukemia, but no systematic analysis of national data has yet been reported. We performed a retrospective cohort study, using data from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute from 1992-2001 in order to compare leukemia incidence rates as a function of race and ethnicity. We identified 709 cases of acute promyelocytic leukemia and analyzed incidence rates by race and sex. Hispanics were not found to have greater lifetime incidence rates than whites, with an incidence relative rate (IRR) of 0.86 that of whites (P=0.17). The age distribution among Hispanics was significantly different from non-Hispanic whites, with greater incidence rates for children ages 1-19 years (IRR=1.9, P=0.02) and adult ages 20-44 years (IRR=1.6, P=0.004). Blacks had lower lifetime incidence rates than non-Hispanic whites (IRR=0.75, P=0.04), Hispanics (IRR=0.64, P=0.007), and Asians (IRR=0.67, P=0.03). Asians did not differ from non-Hispanic whites in lifetime or age-specific incidence rates. These results indicate that while US Hispanics do not have greater lifetime incidence rates of acute promyelocytic leukemia, blacks have lower incidence rates of acute promyelocytic leukemia than Hispanics, non-Hispanic whites, and Asians. 相似文献
28.
29.
Van Landeghem G; Haese P; Lamberts L; Barata J; DeBroe M 《Nephrology, dialysis, transplantation》1997,12(8):1692-1698
Background: The association between aluminium and
dialysis encephalopathy and deterioration of the neurological state during
desferrioxamine treatment of dialysis patients is well established. At
present little is known about the speciation and the mechanisms underlying
the element's neurotoxicity. Methods. Aluminium speciation was performed in
cerebrospinal fluid samples of acutely aluminium-intoxicated dialysis
patients using a recently developed high-performance liquid
chromatographic/electro-thermal atomic absorption spectrometric hybrid
method. Results: Baseline cerebrospinal fluid
aluminium levels of samples taken shortly after the intoxication were low
but elevated (5.0±2.0 &mgr;g/l, n=3) as compared to subjects
with normal renal function (<1 &mgr;g/l). In contrast to the
situation noted in serum and to the iron speciation in cerebrospinal fluid,
aluminium was not bound to transferrin but appeared as two distinct
compounds, the main fraction eluting at the elution volume of aluminium
citrate/silicate. The second compound was not identified. Forty-four hours
after desferrioxamine administration the cerebrospinal fluid aluminium
levels had increased up to a concentration of 10.3±2.5
&mgr;g/l (n=3). This was accompanied by a change in the speciation
profile with aluminium appearing at the elution volume of aluminoxamine.
Conclusion: Our findings may contribute to a better
understanding of the neurotoxic effects of aluminium and its
desferrioxamine chelate in dialysis patients. 相似文献
30.
Evolution of the sperm aster after microinjection of isolated human sperm centrosomes into meiotically mature human oocytes 总被引:3,自引:2,他引:1
This study examined the feasibility of isolating and transferringthe centrosome-containing region of spermatozoa to mature humanoocytes. The findings demonstrate that individual sperm centrosomescan be transferred and are capable of nucleating maternal tubulinto form a well-developed sperm aster in the recipient oocyte.The results are discussed with respect to centrosome functionin early human development and applications in clinical in-vitrofertilization in the treatment of certain forms of male factorinfertility. 相似文献