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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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M. W. J. Boehme R. Waldherr A. Kist S. Riedl R. Walter-Kirst J. Kempeni U. Raeth 《European journal of clinical investigation》1996,26(5):404-410
Cytostatic as well as cytotoxic effects of tumour necrosis factor alpha (TNF-α) therapy have been shown in vitro and in experimental in vivo models. Nevertheless, the mechanism of anti-tumour activity in humans in vivo remains unclear. To determine the role of the vascular lining endothelial cells as important mediators of several immunological interactions, we investigated changes in the levels of the soluble endothelial cell adhesion molecules intercellular adhesion molecule 1, E-selectin and vascular cell adhesion molecule 1 as well as of soluble TNF receptors I and II during systemic therapy with recombinant human rhTNF-α (rhTNF-α). All tests were performed by enzyme-linked immunosorbent assays (ELISAs). The clinical efficacy of the intravenous rhTNF-α therapy was poor. Only one patient with isolated intra-arterial limb perfusion had a delayed, marked, but only temporary necrosis of tumour cells. In contrast, we found a marked, significant and (during therapy) undulating augmented increase in the levels of soluble adhesion molecules as well as of the soluble TNF receptors. Taken together, these data support the hypothesis that a sufficient tumour-specific cellular immunity is required to achieve a clinically apparent efficacy of systemic rhTNF-α therapy in addition to cytokine-dependent inducible activation mechanisms. In this context, the vascular lining endothelial cells might play an important role as mediators of the complex immunological antitumoral activity. 相似文献
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Quantification of motor deficit in Parkinson's disease with a motor performance test series 总被引:2,自引:0,他引:2
M. M. Pinter R. J. Helscher Ch. O. J. Nasel E. Riedl G. Schnaberth 《Journal of neural transmission (Vienna, Austria : 1996)》1992,4(2):131-141
Summary It was the purpose of the present study to quantify the expected motor deficit in parkinsonian patients with the computer assisted Motor Performance Test Series (MPS), version 05.87 by Schuhfried (1987) and to examine which of the motor test variables found correlate at a significance level of p<0.01 with items of motor examination recorded at neurological examination and activities of daily living of the Unified Parkinson's Disease Rating Scale (UPDRS), version 3.0.38 patients with idiopathic Parkinson's disease (PD) stages I–IV according to Hoehn and Yahr, aged 41 to 73 years were studied. The study design, i.e. initial rating by the physician followed immediately by testing of motor function with MPS was strictly adhered to in each patient.Physician's rating of rigor and the scores of the semiquantitative tests (finger taps, hand movements and alternating movements) as expression of hypokinesia and the activities of daily living correlated with the 3 factors of the Motor Performance Test Series at a highly significant level independent of disease stage. Tremor is only partly and never significantly reflected in the motor data measured. Stages I–II and II–IV (Hoehn and Yahr) differ significantly in the representative data of the Motor Performance Test Series.The results of the study support the assumption that MPS is a valid instrument for quantitative measurement of the motor deficit in parkinsonian patients, but that only some subtests are pathognomonic. 相似文献
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