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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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The results of a combination of functional electrocardiographic tests were compared with those of a WHO questionnaire for angina of effort. Coronary disease was verified in 37% of patients with a double diagnosis of angina of effort, and in 100% of cases of angina of effort combined with ischemic electrocardiographic changes.  相似文献   
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Experience in treating 76 patients who were subjected to various sphincter-preserving operations is analysed. It is shown that after subtotal resection of the large intestine with ++abdomino-anal resection of the rectum and pull-through of the right parts of the colon into the anal canal as well as after pull-through of the segment of the transverse colon into the anal canal, the neuro-reflex activity of the musculus sphincter ani internus is destroyed in 55% and reduces in 25% of patients while the reflex activity of the musculus sphincter ani externus is disturbed in 45% of patients and is not restored later. The results bear evidence that the condition of the rectal obturation apparatus does not depend on the segment of the colon subjected to the pull-through operation (cecum, ascending colon, transverse colon). Experience has shown that the results of sphicterometry, electromyography, and electromanometry in various periods after colectomy, mucosectomy of the rectum, and formation of ileorectal anastomosis are much better than those after pull-through operations on various parts of the colon, and return to normal values in 18 months.  相似文献   
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