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51.
52.
Does altered biomechanics cause marrow edema?   总被引:21,自引:0,他引:21  
Schweitzer  ME; White  LM 《Radiology》1996,198(3):851
  相似文献   
53.
BackgroundSecond hip fracture risk is elevated after the first, however whether risk differs with age, by sex or over time is not well known.ObjectiveTo examine the risk of second hip fracture by sex, age and time after first hip fracture.DesignData on all hip fractures in subjects 50 years and older and treated in Norwegian hospitals during 1999–2008 were retrieved. Surgical procedure codes and additional diagnosis codes were used to define incident fractures. Survival analyses with and without adjustment for competing risk of death were used to estimate the risk of second hip fracture.ResultsAmong the 81,867 persons who sustained a first hip fracture, 6161 women and 1782 men suffered a second hip fracture during follow-up. The overall age-adjusted hazard ratio (HR) of a second hip fracture did not differ between the sexes (women versus men, HR = 1.03; 95% confidence interval (CI): 0.98–1.09). Taking competing risk of death into account, the corresponding age-adjusted HR of a second hip fracture was 1.40 (95% CI: 1.33–1.47) in women compared to men. The greater risk in women was due to a higher mortality in men. Based on competing risk analyses, we estimate that 15% of women and 11% of men will have suffered a second hip fracture within 10 years after the first hip fracture. The ten-year cumulative incidence was above 10% in all age-groups, except in men 90 years and older.ConclusionFracture preventive strategies have a large potential in both women and men who suffer their first hip fracture due to the high risk of another hip fracture.  相似文献   
54.

Background

Information from randomized trials on the role of combination chemotherapy in the adjuvant treatment of pancreatic adenocarcinoma is limited. This randomized phase II trial aimed to identify the most promising regimen warranting phase III evaluation.

Methods

Therapy-naive patients, age 18?C75?years, Karnofsky Performance Status (KPS) >60, gross total resection of stage IB?CIII pancreatic adenocarcinoma, stratified for center and surgical margins, were randomly assigned to receive either gemcitabine 1?g/m2 weekly on days 1, 8, and 15 (arm A) or the PEFG regimen (cisplatin and epirubicin 40?mg/m2, day 1; gemcitabine 600?mg/m2, days 1, 8; 5-fluorouracil 200?mg/m2 daily, days 1?C28) (arm B). Chemotherapy was administered every 4?weeks for 3?months and followed by irradiation concurrent to continuous infusion of 5-fluorouracil 250?mg/m2 daily. Primary endpoint was the probability of being disease-free at 1?year from surgery. Assuming P0?=?35% and P1?=?55%, ???=?.05 and ???=?.10, the study was to enroll 51 patients per arm.

Results

A total of 102 patients were randomized; 100 were eligible (arm A: 51; arm B: 49). Baseline characteristic (A/B) were: Median age was 61/60?years; 75% had KPS >80 75/76%; 36% grade 3 tumor 29/43%, 79% stage IIB/III 75/84%, 31% R1 resection 35/29%. Survival figures (A/B) were: Median disease-free survival was 11.7 and 15.2?months; 1-year disease-free survival 49.0% (95% confidence interval [95% CI] 35?C63%) and 69.4% (95% CI 56?C83%); median survival 24.8 and 28.9?months. Combination chemotherapy produced more hematological toxicity without relevant differences in nonhematological toxicities.

Conclusions

The 4-drug regimen deserves further assessment in resectable pancreatic cancer.  相似文献   
55.
异基因造血干细胞移植(hematopoieticcelltransplantation,HCT)后代谢综合征的发生主要由预处理导致的神经激素系统紊乱、血管内皮损伤、移植物的免疫和炎症作用以及继发的移植物抗宿主病及其治疗等引起。对代谢综合征及其组分(糖尿病、高血压、血脂紊乱等)的筛查可以尽早地调整治疗策略,控制危险因素的发生,进而降低远期的心血管疾病的发生率和致死率。为此,美国的研究人员回顾性分析了86例异基因HCT受者代谢综合征的发生情况,并与代谢综合征在普通人群中的流行情况进行比较。  相似文献   
56.
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58.
AIMS: To determine the association of HLA with diabetic end-stage renal disease (DESRD) in Saskatchewan aboriginal people. METHODS: This was a retrospective study of HLA profiles in four groups of Saskatchewan residents with ESRD diagnosed from 1980 to 1998: aboriginal people with and without DESRD, and non-aboriginal people with and without DESRD. The aboriginal DESRD group was also subdivided into those 50 years of age. Frequencies of individual and combinations of HLA antigens were compared between groups and subgroups. RESULTS: HLA data were available for 634 subjects. Young aboriginal people with DESRD had a higher frequency of HLA-A2 than older AB DESRD subjects (69 vs. 36%; p = 0.03), and of HLA-DR4 and/or DR8 compared to older AB DESRD subjects (91 vs. 68%; p = 0.07) and AB non-DESRD subjects (91 vs. 67%; p = 0.03). Over 65% of young AB DESRD subjects had either an A2/DR4 or A2/DR8 haplotype (odds ratio 5.09 [confidence intervals 1.35, 20.15] versus older AB DESRD subjects; odds ratio 3.32 [confidence intervals 1.20, 9.3] versus AB non-DESRD subjects). Forty percent of young AB DESRD subjects were homozygous for at least one of A2, DR4 or DR8. CONCLUSIONS: Our findings suggest that DESRD in young AB subjects with T2DM has a genetic basis related to HLA.  相似文献   
59.
Background: Recently, various studies have questioned the efficacy of intraoperative acute normovolemic hemodilution (ANH) in reducing bleeding and the need for allogeneic transfusions in cardiac surgery. The aim of the present study was to reevaluate the effects of a low-volume ANH in elective, adult open-heart surgery.

Methods: Two hundred four consecutive adult patients undergoing cardiac surgery were prospectively randomized in a nonblinded manner into two groups: ANH group (103 patients), where 5-8 ml/kg of blood was withdrawn before systemic heparinization and replaced with colloid solutions, and a control group, where no hemodilution was performed (101 patients). Procedures included single and multiple valve surgery, aortic root surgery, coronary surgery combined with valve surgery, or partial left ventriculectomy. The purpose of the study was to evaluate the efficacy of ANH in reducing the need for allogeneic blood components. Routine hematochemical evaluations, perioperative blood loss, major complications, and outcomes were also recorded.

Results: No differences were found between the groups regarding demographics, baseline hematochemical data, and operative characteristics. There was no difference in the amount of transfusions of packed red cells, fresh frozen plasma, platelet concentrates, total number of patients transfused (control group, 36%vs. ANH group, 34.3%;P = 0.88), and amount of postoperative bleeding (control group, 412 ml [313-552 ml]vs. ANH group, 374 ml [255-704 ml]) (median [25th-75th percentiles]);P = 0.94. Further, perioperative complications, postoperative hematochemical data, and outcomes were not different.  相似文献   

60.
Hip fractures are associated with high excess mortality. Education is an important determinant of health, but little is known about educational inequalities in post‐hip fracture mortality. Our objective was to investigate educational inequalities in post‐hip fracture mortality and to examine whether comorbidity or family composition could explain any association. We conducted a register‐based population study of Norwegians aged 50 years and older from 2002 to 2010. We measured total mortality according to educational attainment in 56,269 hip fracture patients (NORHip) and in the general Norwegian population. Both absolute and relative educational inequalities in mortality in people with and without hip fracture were compared. There was an educational gradient in post‐hip fracture mortality in both sexes. Compared with those with primary education only, the age‐adjusted relative risk (RR) of mortality in hip fracture patients with tertiary education was 0.82 (95% confidence interval [CI] 0.77–0.87) in men and 0.79 (95% CI 0.75–0.84) in women. Additional adjustments for Charlson comorbidity index, marital status, and number of children did not materially change the estimates. Regardless of educational attainment, the 1‐year age‐adjusted mortality was three‐ to fivefold higher in hip fracture patients compared with peers in the general population without fracture. The absolute differences in 1‐year mortality according to educational attainment were considerably larger in hip fracture patients than in the population without hip fracture. Absolute educational inequalities in mortality were higher after hip fracture compared with the general population without hip fracture and were not mediated by comorbidity or family composition. Investigation of other possible mediating factors might help to identify new targets for interventions, based on lower educational attainment, to reduce post‐hip fracture mortality. © 2015 American Society for Bone and Mineral Research.  相似文献   
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