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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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ObjectivesThis study examined whether late-onset (versus early-onset) suicidal behavior is associated with worse cognition.MethodsParticipants included 278 adults aged 50+ years (56 nonpsychiatric comparison group; 67 nonsuicidal depressed older adults; 63 depressed suicide ideators; and 44 late-onset (55+ years) and 48 early-onset suicide attempters (<55 years). Using a case-control design, this study examined group differences in global cognition, episodic memory, information processing speed, and executive functioning, assessed using the Repeatable Battery of Neuropsychological Status and the Trail Making Test from the Delis-Kaplan Executive Function System. Linear regression was used for data analyses.ResultsBoth attempter groups displayed worse executive functioning than nonsuicidal depressed older adults. Late-onset attempters additionally displayed poorer global cognition and processing speed than nonsuicidal depressed older adults and poorer memory than early-onset attempters.ConclusionsLate-onset suicidal behavior is associated with worse performance in a broad range of cognitive domains, possibly reflective of a dementia prodrome.  相似文献   
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CONTEXT: Electroconvulsive therapy (ECT) is the most effective biological treatment for major depression. However, there is little agreement about clinically useful predictors of acute ECT outcomes. OBJECTIVE: To assess whether age, sex, burden of comorbid physical illness, age at onset, history of recurrence, episode duration, chronic depression or comorbid dysthymia, melancholic features, episode severity, and medication resistance are predictors of remission after an acute course of ECT. DESIGN: We performed an analysis using data gathered prospectively in 328 patients with unipolar major depression (according to Research Diagnostic Criteria) treated with ECT. The study was conducted from 1993 through 1999. Patients had a pretreatment score of 21 or higher on the 24-item Hamilton Rating Scale for Depression (HAM-D). Treatment history was assessed using the Antidepressant Treatment History Form. Remission was defined as a 24-item HAM-D score of 10 or less and a 60% or more relative reduction of the HAM-D score. RESULTS: On univariate logistic regression, statistically significant predictors of nonremission were chronic depression/dysthymia, medication resistance, longer episode duration, and younger age. On backward elimination logistic regression, only medication resistance (OR = 1.67, 95% CI = 1.05 to 2.67) and chronic depression/ dysthymia (OR = 1.84, 95% CI = 1.06 to 3.21) were statistically significant predictors of nonremission. CONCLUSIONS: In patients with major depression, lower rates of remission after acute ECT are associated with medication resistance and chronicity, but not with age or burden of physical illness.  相似文献   
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OBJECTIVE: Deficits in executive functions may play an important role in late-life suicide; however the association is understudied. This study examined cognitive function in general and executive functioning specifically in depressed elderly with and without suicidal ideation and attempts. DESIGN: Case-control study. Setting: University-affiliated psychiatric hospital. PARTICIPANTS: We compared 32 suicidal depressed participants aged 60 and older with 32 non-suicidal depressed participants equated for age, education, and gender. MEASUREMENTS: We assessed global cognitive function and executive function with the Dementia Rating Scale (DRS) and the Executive Interview (EXIT25), respectively. RESULTS: Suicidal and non-suicidal depressed groups were comparable in terms of severity of depression and burden of physical illness. Suicidal participants performed worse on the EXIT25, and on the DRS total scale, as well as on Memory and Attention subscales. The differences were not explained by the presence of dementia, substance use, medication exposure, or brain injury from suicide attempts. CONCLUSIONS: Poor performance on tests of executive function, attention, and memory is associated with suicidal behavior in late-life depression.  相似文献   
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