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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
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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
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Intestinal schistosomiasis japonica: CT-pathologic correlation 总被引:1,自引:0,他引:1
Lee RC; Chiang JH; Chou YH; Rubesin SE; Wu HP; Jeng WC; Hsu CC; Tiu CM; Chang T 《Radiology》1994,193(2):539
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V Bongertz M L Guimar?es M F Soares-da-Costa V G Veloso F I Bastos C L Szwarcwald M Derrico P R Telles J H Pilloto E C Jo?o Filho M G Morgado 《Journal of clinical virology》1999,12(1):27-36
BACKGROUND: Antibody binding assays carried out by our group have consistently indicated a higher reactivity of sera from male HIV-1 infected individuals. This study was carried out in order to analyze the importance of gender, route of transmission, disease progression and HIV-1 genotype in seroreactivity assays. STUDY DESIGN: Specificity of antibody binding was studied in plasma of 247 HIV-1 seropositive individuals belonging to patient groups of pregnant women, injecting drug users (IDUs) and recent seroconvertors, resident in Rio de Janeiro, RJ. Recognition of synthetic peptides corresponding to antigenically important epitopes in the envelope of HIV-1 (gp41 immunodominant epitope, V3 loop, V2 loop and gp41 735-752 epitope) was determined. RESULTS: The immunodominant gp41 peptide (amino acids 594-613, HIV-1 MN sequence) was recognized by 85% of all plasma tested. Reactivity with the gp41 735-752 peptide and gp120 V2 loop peptides was low but quite variable, being generally more often specific to a Brazilian V2 peptide used than to the HIV-1 MN derived V2 peptide. The overall recognition of the different V3 peptides tested varied from 41 to 76%. Patients with more advanced disease showed a more frequent reactivity with the peptides studied than did asymptomatic patients. Statistically significant differences in peptide recognition were observed by multiple logistic analyses comparing plasma derived from individuals infected by blood or sexual HIV transmission, adjusting for disease progression and gender. Plasma from individuals infected by sexual transmission showed lower peptide recognition than did plasma from individuals infected through HIV positive blood. Association attempts between seroreactivity and genotype indicated that plasma derived from patients infected with HIV-1 of the F subtype showed highest recognition of heterologous V3 peptides, as well as a slightly more frequent recognition of the non-V3 peptides tested. Recognition of homologous peptides was generally higher than recognition of heterologous peptides. Differences were most pronounced between the prototypical HIV-1 B subtype and the Brazilian B" variant of this subtype but almost non-existent between the HIV-1 B and F subtypes. CONCLUSIONS: Individual gender was shown to be a confounder when investigating the relationships of peptide reaction to HIV-1 route of transmission through multivariate statistical methods: patients infected by blood transmission (IDU) present higher frequency of peptide recognition than individuals infected by sexual HIV-1 transmission. Plasma from individuals infected with the B" variant (GWG) of B subtype HIV-1 showed lower heterologous peptide recognition than that from HIV-1 B (GPG) or F infected individuals. 相似文献