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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 tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403 amino acid dual specificity phosphatase (protein tyrosine phosphatase; PTPase), was shown recently to play a broad role in human malignancy. Somatic PTEN deletions and mutations were observed in sporadic breast, brain, prostate and kidney cancer cell lines and in several primary tumours such as endometrial carcinomas, malignant melanoma and thyroid tumours. In addition, PTEN was identified as the susceptibility gene for two hamartoma syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD families and seven BZS families was screened for germline PTEN mutations. PTEN mutations were identified in 30 of 37 (81%) CD families, including missense and nonsense point mutations, deletions, insertions, a deletion/insertion and splice site mutations. These mutations were scattered over the entire length of PTEN , with the exception of the first, fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD mutations identified in this exon. Seven of 30 (23%) were within the core motif, the majority (five of seven) of which were missense mutations, possibly pointing to the functional significance of this region. Germline PTEN mutations were identified in four of seven (57%) BZS families studied. Interestingly, none of these mutations was observed in the PTPase core motif. It is also worthy of note that a single nonsense point mutation, R233X, was observed in the germline DNA from two unrelated CD families and one BZS family. Genotype-phenotype studies were not performed on this small group of BZS families. However, genotype-phenotype analysis inthe group of CD families revealed two possible associations worthy of follow-up in independent analyses. The first was an association noted in the group of CD families with breast disease. A correlation was observed between the presence/absence of a PTEN mutation and the type of breast involvement (unaffected versus benign versus malignant). Specifically and more directly, an association was also observed between the presence of a PTEN mutation and malignant breast disease. Secondly, there appeared to be an interdependent association between mutations upstream and within the PTPase core motif, the core motif containing the majority of missense mutations, and the involvement of all major organ systems (central nervous system, thyroid, breast, skin and gastrointestinal tract). However, these observations would need to be confirmed by studying a larger number of CD families.   相似文献   
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The transverse rectus abdominis musculocutaneous (TRAM) flap has been widely used for reconstruction of the breast. Partial loss of the flap is still a problem, however, and venous congestion may cause partial necrosis of the flap. There are few studies of the venous anatomy of the TRAM flap that compares with that of the arterial system, so the aim of this study was to investigate the venous anatomy of the TRAM flap and assess its drainage pathway using venography. A mixture of barium and gelatin were injected through the cutaneous veins such as the superficial inferior epigastric vein (SIEV), the superficial circumflex iliac vein (SCIV), or the perforating branch of the deep inferior epigastric vein (DIEV) in 11 hemiTRAM flaps. Venograms of TRAM flaps were taken, and the venous anatomy evaluated. The study showed that it consisted of the dominant superficial venous system, the SIEV and SCIV, and the secondary deep venous system, and the perforating vein of DIEV (DIEV perforator). In addition, we saw the large communicating veins between the SIEV and DIEV perforator near the umbilicus. We think that these communicating veins, which are considered as the DIEV perforators between the superficial and deep venous system, are an important venous drainage pathway after the TRAM flap has been raised.  相似文献   
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The high prevalence of obesity and associated chronic conditions in persons with severe and persistent mental illness has contributed to a mortality rate that is nearly two times higher than the overall population. In 2008, the Central O‘ahu Community Mental Health Center of the Hawai‘i State Department of Health, Adult Mental Health Division began an unfunded, health counseling intervention pilot project to address such concerns for the health of persons with severe and persistent mental illness. This article reviews the results of this intervention. Forty-seven persons with schizophrenia or related disorders were included in the intervention which involved health counseling and monitoring of weight as a risk factor for chronic disease. After five years of counseling and monitoring, medical chart reviews were conducted for each person for data on weight change. Analysis showed weight loss and improvements in body mass index. The results of this project show potential for long-term counseling and monitoring as an intervention for obesity in persons with severe and persistent mental illness.  相似文献   
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Radiology report errors occur for many reasons including the use of pre-filled report templates, wrong-word substitution, nonsensical phrases, and missing words. Reports may also contain clinical errors that are not specific to the speech recognition including wrong laterality and gender-specific discrepancies. Our goal was to create a custom algorithm to detect potential gender and laterality mismatch errors and to notify the interpreting radiologists for rapid correction. A JavaScript algorithm was devised to flag gender and laterality mismatch errors by searching the text of the report for keywords and comparing them to parameters within the study’s HL7 metadata (i.e., procedure type, patient sex). The error detection algorithm was retrospectively applied to 82,353 reports 4 months prior to its development and then prospectively to 309,304 reports 15 months after implementation. Flagged reports were reviewed individually by two radiologists for a true gender or laterality error and to determine if the errors were ultimately corrected. There was significant improvement in the number of flagged reports (pre, 198/82,353 [0.24 %]; post, 628/309,304 [0.20 %]; P = 0.04) and reports containing confirmed gender or laterality errors (pre, 116/82,353 [0.014 %]; post, 285/309,304 [0.09 %]; P < 0.0001) after implementing our error notification system. The number of flagged reports containing an error that were ultimately corrected improved dramatically after implementing the notification system (pre, 17/116 [15 %]; post, 239/285 [84 %]; P < 0.0001). We developed a successful automated tool for detecting and notifying radiologists of potential gender and laterality errors, allowing for rapid report correction and reducing the overall rate of report errors.  相似文献   
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Cu/Zn superoxide dismutase (Cu/Zn SOD), glutathione peroxidase (GPx) and catalase, which are the three main enzymes involved in cellular protection against damage due to oxygen-derived free radicals have been assayed in plasma and erythrocytes obtained from subjects with dementia of the Alzheimer type (DAT) and from controls. Blood samples were obtained from 25 patients with DAT and from age-matched subjects without diagnoses of neurological disease (non-DAT), as well as from younger individuals (reference group). Using appropriate statistical procedures, the three enzyme activities measured in blood of the elderly were decreased if compared to the younger reference group. Moreover, a significant increase in erythrocyte Cu/Zn SOD and catalase activities of DAT patients was observed compared to the non-DAT group. These results are discussed taking the free radical theory of aging into consideration.  相似文献   
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