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11.
BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors. 相似文献
12.
E Marchi F S Vargas M M Acencio L Antonangelo E H Genofre L R Teixeira 《The European respiratory journal》2006,28(5):929-932
Intrapleural instillation of talc is used to produce pleurodesis in cases of recurrent malignant pleural effusions. The mechanisms by which pleurodesis is produced remain unknown but may involve either injury or activation of the mesothelium. The aim of the current study was to assess the inflammatory response of pleural mesothelial cells to talc in an experimental model in rabbits. A group of 10 rabbits were injected intrapleurally with talc (200 mg.kg(-1)) and undiluted pleural fluid was collected after 6, 24 or 48 h for measurement of interleukin (IL)-8, vascular endothelial growth factor (VEGF) and transforming growth factor (TGF)-beta1. Samples of pleura were studied to assess the inflammatory infiltrate and mesothelial cell viability. The pleural fluid IL-8 concentration peaked at 6 h, whereas VEGF and TGF-beta1 concentrations increased steadily over 48 h. Immunohistochemistry for cytokeratin showed a preserved layer of mesothelial cells despite the intense inflammatory pleural reaction. In conclusion, it is proposed that the mesothelial cell, although injured by the talc, may actively mediate the primary inflammatory pleural response in talc-induced pleurodesis. 相似文献
13.
Sandra Guerra A Teixeira Pinto José Ribeiro José Oliveira José Duarte Jorge Mota 《Revista portuguesa de cardiologia》2003,22(2):167-182
An important aspect of preventive medicine is to identify subjects at risk as soon as possible, so preventive strategies can be introduced at early ages. The justification for this strategy is twofold: firstly, the assumption that children maintain a particular high value of a risk factor for disease throughout life; and secondly, the assumption that lowering the level of the risk factor in early life will have a greater impact on the disease than will risk factor changes in later life. In epidemiology the analysis of such factors over time is referred to as tracking. Tracking analysis has been applied to risk factors for cardiovascular diseases (CVD) in pediatric years. The aims of this study were: I) to analyze the stability of biological risk factors [high blood pressure (BP), high percentage of fat mass (%FM) and high total cholesterol (TC)] and lifestyle risk factors [low physical activity index (PAI)] in isolation; and II) to analyze the stability of zero, one, two or three biological risk factors. There were two evaluations in 692 children and adolescents (325 boys and 367 girls), aged between 8 and 15 years. The quartiles, adjusted for age and gender, were the criterion used to identify subjects with biological risk factors (fourth quartile) and with lifestyle risk factors (first quartile) for CVD. The stability was calculated through the relative frequency of subjects who maintained or changed quartile between the two evaluations. There is stability for biological risk factors as well as for behavioral and/or lifestyle risk factors. However, the highest stability is seen in biological risk factors. 相似文献
14.
Proximal radioulnar transposition in an elbow dislocation is rare. Only three cases have been recorded. Translocation can easily be missed unless radiographs are carefully examined. Proximal radioulnar translocation has been believed to be iatrogenic. The injury we report was not iatrogenic, and mechanical locking of radial head and neck fracture necessitated open reduction. 相似文献
15.
Rosenberg ZS; Jahss MH; Noto AM; Shereff MJ; Cheung Y; Frey CC; Norman A 《Radiology》1988,167(2):489-493
Computed tomography (CT) was performed in 42 patients with 49 clinically suspected tears of the posterior tibial tendon. Twenty-eight of the 49 suspected tears were subsequently surgically explored and repaired. Three patterns of tendon abnormalities were recognized on CT scans: type I-intact, hypertrophied, heterogeneous tendon; type II-attenuated tendon; and type III-absence of a portion of a tendon. Types I and II correlated with partial rupture seen during surgery, and type III correlated with complete rupture of the tendon. CT findings were accurate in 96% of the patients who underwent surgery. In four cases (14%), tendon rupture was seen on CT scans, but the extent of the injury was underestimated and the rupture was misclassified. Reactive periostitis of the distal tibia was seen in 71% of diseased tendons and may represent an important factor in the diagnosis of tendon rupture. 相似文献
16.
17.
Fabricio B Teixeira 《Practical procedures & aesthetic dentistry》2006,18(3):S7-11
Several factors can contribute to the clinician's ability to achieve success in endodontic therapy. The importance of the coronal seal to positive endodontic outcomes has been established in numerous studies; fracture strength also has a significant influence on the prognosis of an endodontically treated tooth. This presentation discusses the role of these two factors in contemporary endodontic therapy and demonstrates how the utilization of an adhesively bonded, synthetic root-filling system can support the practitioner's management of nonvital teeth. 相似文献
18.
Luzitano Brando Ferreira Celso Teixeira Mendes Cludia Emília Vieira Wiezel Marcelo Rizzatti Luizon Aguinaldo Luiz Simes 《American journal of human biology》2006,18(5):702-705
Allelic frequencies of eight autosomal short‐tandem repeat (STR) loci (TH01, TPOx, CSF1PO, vWA, FES/FPS, F13A1, F13B, and CD4) were determined in 400 individuals born in the State of São Paulo. No significant deviations from Hardy‐Weinberg equilibrium were found in any loci analyzed. The Unweighted Pair‐Group Method with Arithmetic Mean (UPGMA) tree constructed based on genetic distances revealed that the present population was grouped with Europeans, and separated from African and Amerindian populations. Estimates of admixture components based on the gene identity method revealed 79% European, 14% African, and 7% Amerindian contributions to this Brazilian population sample. Am. J. Hum. Biol. 18:702–705, 2006. © 2006 Wiley‐Liss, Inc. 相似文献
19.
20.
F. Teixeira Brandt C. D. Costa Albuquerque J. W. Barros Leal 《International urogynecology journal》1997,8(6):332-335
We report on the vaginal mucosal folds (VMF) at the urethral external meatus. Resection of the VMF reduces the dispersed micturition
and other urinary symptoms.
EDITORIAL COMMENT: The investigators describe the presence of a vaginal mucosal fold (VMF) just dorsal to the urethral meatus
and its relationship to voiding abnormalities. VMF were found on physical examination in 8.9% of the clinic population, all
of whom complained of dispersed micturition, and 79% also experienced other voiding abnormalities. The complaint of dispersed
micturition was successfully treated with excision of the VMF, and the other associated symptoms were improved. This structure
should be routinely looked for on physical examination, especially in patients with voiding symptoms. Only further investigation
of this newly described entity at other centers around the world will determine the incidence of the anatomic finding and
the prevalence of associated voiding disturbances across different populations. 相似文献