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排序方式: 共有1023条查询结果,搜索用时 46 毫秒
71.
Switzer GE Dew MA Goycoolea JM Myaskovsky L Abress L Confer DL 《Transplantation》2004,77(10):1529-1534
BACKGROUND: The National Marrow Donor Program (NMDP) has had remarkable success at recruiting potential bone marrow donors and recently has become increasingly focused on the retention of registered volunteers. This study extends the authors' work examining factors associated with attrition from the registry. Its goal was to determine which characteristics from six psychosocial domains were associated with attrition at two key stages leading to donation. METHODS: Questionnaires were mailed to potential donors after they were contacted as a potential match and had decided whether or not to continue toward donation. Our final sample included 1,727 volunteers who decided to continue with typing at the DR stage and 195 volunteers who decided to continue at the confirmatory typing (CT) stage as well as 179 and 169 individuals, respectively, who declined further participation in the registry at DR and CT stages. RESULTS: Bivariate analyses indicated that multiple factors in all six domains (demographics, volunteer-related, general psychosocial, recruitment-related, donation-related, and contact with center staff) were associated with discontinued registry participation. Logistic regression indicated that unique associations were concentrated in volunteer-related, donation-related, and contact with center domains. CONCLUSIONS: Findings suggested that intrinsic commitment to donation, more realistic expectations, fewer medical concerns, and greater contact with the donor center were all associated with lower attrition. Possible interventions to reduce attrition are discussed. 相似文献
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73.
Potter AA Klashinsky S Li Y Frey E Townsend H Rogan D Erickson G Hinkley S Klopfenstein T Moxley RA Smith DR Finlay BB 《Vaccine》2004,22(3-4):362-369
Cattle are an important reservoir of Escherichia coli O157:H7 leading to contamination of food and water, and subsequent human disease. This pathogen colonizes its hosts by producing several proteins such as Tir and EspA that are secreted by a type III secretion system. These proteins play a role in colonization of the intestine, suggesting that they might be useful targets for the development of a vaccine to reduce levels of this organism in cattle. Vaccination of cattle with proteins secreted by E. coli O157:H7 significantly reduced the numbers of bacteria shed in feces, the numbers of animals that shed, and the duration of shedding in an experimental challenge model. Vaccination of cattle also significantly (P=0.04) reduced the prevalence of E. coli O157:H7 in a clinical trial conducted in a typical feedlot setting. This strategy suggests it is possible to vaccinate cattle to decrease the level of E. coli O157:H7 shedding for the purpose of reducing the risk of human disease. 相似文献
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75.
Improved survival for adenocarcinoma of the ampulla of Vater: fifty-five consecutive resections 总被引:12,自引:0,他引:12
Duffy JP Hines OJ Liu JH Ko CY Cortina G Isacoff WH Nguyen H Leonardi M Tompkins RK Reber HA 《Archives of surgery (Chicago, Ill. : 1960)》2003,138(9):941-8; discussion 948-50
HYPOTHESIS: After resection of an adenocarcinoma of the ampulla of Vater, certain clinical and pathologic characteristics influence long-term survival. DESIGN: Retrospective case series. SETTING: Major academic medical and pancreatic surgical center. PATIENTS: Fifty-five consecutive patients who underwent Whipple resection for ampullary adenocarcinoma from 1988 through 2001. INTERVENTIONS: Pylorus-preserving Whipple resection in 32 patients and standard Whipple resection in 23 patients. MAIN OUTCOME MEASURES: Postoperative survival. A multivariate Cox proportional hazards model was used to determine the effects of various factors on long-term survival after resection. RESULTS: There were no operative deaths, and all patients left the hospital. After a mean follow-up of 46.9 months, the overall 5-year Kaplan-Meier survival estimate was 67.7%. The median survival of the entire group has not yet been reached. Five-year postoperative survival estimates for node-negative (n = 32) and node-positive patients (n = 23) were 76.5% and 53.4%, respectively (P =.26). Patients whose tumors demonstrated perineural invasion (n = 12) had a 5-year survival estimate of 29.2% vs 78.8% for those whose did not (P<.001). On multivariate analysis, the absence of perineural invasion (P<.001) was an independent predictor of significantly improved postoperative survival. CONCLUSIONS: Compared with previous reports from our own and other centers, this series demonstrates improved postoperative survival by 10% to 20% in patients undergoing Whipple resection for adenocarcinoma of the ampulla of Vater. The reasons for this improved outcome are unclear, and the effect of adjuvant treatment cannot be determined from this analysis. The major factor associated with prolonged survival was the absence of perineural invasion in the resected tumor specimen. 相似文献
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77.
Zhang W Vajsar J Cao P Breningstall G Diesen C Dobyns W Herrmann R Lehesjoki AE Steinbrecher A Talim B Toda T Topaloglu H Voit T Schachter H 《Clinical biochemistry》2003,36(5):339-344
OBJECTIVES: Mutations disrupting the interaction of extra-cellular ligands and alpha-dystroglycan are responsible for an etiologically heterogeneous group of autosomal recessive congenital muscular dystrophies (CMD) that can have associated brain and eye abnormalities. The objective is to develop a diagnostic test for one of these CMDs, Muscle-Eye-Brain disease (MEB), due to mutations in the gene encoding Protein O-Mannosyl beta-1,2-N-acetylglucosaminyltransferase 1 (POMGnT1). DESIGN AND METHODS: POMGnT1 enzyme activity was determined in extracts of muscle biopsies from four MEB patients and various controls using commercially available reagents. RESULTS: All four MEB muscle samples showed a highly significant decrease in POMGnT1 activity relative to controls. CONCLUSIONS: The assay of POMGnT1 activity in MEB muscle provides a rapid and relatively simple diagnostic test for this disease. CMDs associated with brain malformations such as MEB, WWS and FCMD are heterogenous in clinical presentation and on radiologic examination, suggesting that POMGnT1 assays of muscle biopsies should be used as a screening procedure for MEB in all CMD patients associated with brain malformations. 相似文献
78.
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80.
Ying-Yeh Chen Pei-Chen Tsai Pao-Huan Chen Chun-Chieh Fan Galen Chin-Lun Hung Andrew T. A. Cheng 《Social psychiatry and psychiatric epidemiology》2010,45(3):363-369