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991.
Heather M Macdonald Kyle K Nishiyama Jian Kang David A Hanley Steven K Boyd 《Journal of bone and mineral research》2011,26(1):50-62
In this cross‐sectional study, we aimed to predict age‐related changes in bone microarchitecture and strength at the distal radius (DR) and distal tibia (DT) in 644 Canadian adults (n = 442 women and 202 men) aged 20 to 99 years. We performed a standard morphologic analysis of the DR and DT with high‐resolution peripheral quantitative computed tomography (pQCT) and used finite‐element analysis (FEA) to estimate bone strength (failure load) and the load distribution. We also calculated a DR load‐to‐strength ratio as an estimate of forearm fracture risk. Total bone area, which was 33% larger in young men at both sites, changed similarly with age in women and men at the DT but increased 17% more in men than in women at the DR (p < .001). Trabecular number and thickness (Tb.Th) were 7% to 20% higher in young men than in young women at both sites, and with the exception of Tb.Th at the DR, which declined more with age in men (?16%) than in women (?2%, p < .01), the age‐related decline in these outcomes was similar in women and in men. In the cortex, porosity (Ct.Po) was 31% to 44% lower in young women than in young men but increased 92% to 176% more with age in women than in men (p < .001). The DR cortex carried 14% more load in young women than in young men, and the percentage of load carried by the DR cortex did not change with age in women but declined by 17% in men (p < .01). FEA‐estimated bone strength was 34% to 47% greater in young men, but the predicted change with age was similar in both sexes. In contrast, the load‐to‐strength ratio increased 27% more in women than in men with age (p < .01). These results highlight important site‐ and sex‐specific differences in patterns of age‐related bone loss. In particular, the trends for less periosteal expansion, more porous cortices, and a greater percentage of load carried by the DR cortex in women may underpin sex differences in forearm fracture risk. © 2011 American Society for Bone and Mineral Research. 相似文献
992.
993.
Crawford ED Moul JW Rove KO Pettaway CA Lamerato LE Hughes A 《BJU international》2011,108(11):1743-1749
Study Type – Prognosis (inception cohort) Level of Evidence 1b What’s known on the subject? and What does the study add? Large population screening trials like the ERSPC, PCPT and PLCO have noted that men with seemingly low PSA (even as low as 0.5 ng/dL) still can have prostate cancer. Despite these findings, PSA is still predominantly used as a current indicator for possible presence of prostate cancer rather than also serving as a prognostic marker. This study examines a larger number of men in a diverse US population to determine the prognostic value of a man’s baseline or first PSA.
OBJECTIVES
? To assess the value of a PSA threshold of 1.5 ng/mL as a predictor of increased prostate cancer risk over a four‐year period based on a man’s first PSA test, including racial differences. ? To review the risk of progression of benign prostatic hyperplasia (BPH) based on a similar PSA threshold.PATIENTS AND METHODS
? A retrospective review involving 21 502 men from a large Midwestern health system was performed. ? Men at least 40 years old with baseline PSA values between 0 and 4.0 ng/mL and at least four years of follow‐up after initial PSA test were included. ? Optimal PSA threshold and predictive value of PSA for development of prostate cancer were calculated.RESULTS
? Prostate cancer rates were 15‐fold higher in patients with PSA ≥1.5 ng/mL vs patients with PSA <1.5 ng/mL (7.85% vs 0.51%). ? African American patients with baseline PSA <1.5 ng/mL faced prostate cancer rates similar to the whole study population (0.54% vs 0.51%, respectively), while African American patients with PSA 1.5–4.0 ng/mL faced a 19‐fold increase in prostate cancer.CONCLUSION
? Both Caucasian and African American men with baseline PSA values between 1.5 and 4.0 ng/mL are at increased risk for future prostate cancer compared with those who have an initial PSA value below the 1.5 ng/mL threshold. ? Based on a growing body of literature and this analysis, it is recommended that a first PSA test threshold of 1.5 ng/mL and above, or somewhere between 1.5 and 4.0 ng/mL, represent the Early‐Warning PSA Zone (EWP Zone). ? This should serve to inform patients and clinicians alike to future clinical activities with respect to prostate cancer and BPH. 相似文献994.
995.
Kirk KL Jones EM Potter BK Osborn PM Ficke JR 《Journal of surgical orthopaedic advances》2011,20(1):19-22
Throughout the current conflicts in Afghanistan and Iraq, there have been more than 1100 combat-related major limb amputations, with approximately 80% involving the lower extremity. There is, however, a paucity of data regarding the number of amputations below the level of the ankle. Although not as common, partial foot amputations, in the appropriate setting, offer a way to improve function and decrease energy consumption when compared to proximal amputations. Sound surgical tenets are prerequisite for successful outcomes when performing a distal amputation. Maintaining a robust soft tissue envelope allowing for tension-free wound closure is paramount in determining the feasibility of a partial foot amputation. Careful consideration of tendon balancing is also of utmost importance in avoiding common complications of contracture and deformity. Partial foot amputations present a viable surgical option for successful outcomes and maximization of patient function in the combat injured when certain criteria are met. 相似文献
996.
997.
Musil CM Warner CB Zauszniewski JA Jeanblanc AB Kercher K 《The journals of gerontology. Series B, Psychological sciences and social sciences》2006,61(2):S89-S98
OBJECTIVES: We used McCubbin's Resiliency Model of Family Stress, Adjustment and Adaptation ( McCubbin, Thompson, & McCubbin, 2001) to examine how demographic factors, family stress, grandmother resourcefulness, support, and role reward affect perceptions of family functioning for grandmothers raising grandchildren, grandmothers living in multigenerational households, and grandmothers not caregiving for grandchildren. METHODS: A sample of 486 grandmothers completed a mailed questionnaire. We used structural equation modeling to (a) test the effects of demographic factors (i.e., grandmother's age, race, marital status, and employment), family stressful life events and strain, grandmother's resourcefulness, subjective and instrumental support, and role reward on perceptions of family functioning for each grandmother group; (b) evaluate differences in the measurement and structural models between the grandmother groups using multisample analysis; and (c) test the model on the full sample, coding for caregiver status. RESULTS: The models did not differ significantly by grandmother group; therefore we assessed the composite model using a multisample analysis. We found general support for the resiliency model and equivalence of the models across grandmother groups. Less support, resourcefulness, and reward, and more intrafamily strain and stressful family life events contributed to perceptions of worse family functioning. DISCUSSION: Findings demonstrate the importance of the quality of family functioning for grandmothers in all types of families. 相似文献
998.
999.
Audrey H. Lau Kyle Soltys Rakesh K. Sindhi Geoffrey Bond George V. Mazariegos Michael Green 《Pediatric transplantation》2010,14(4):549-553
Lau AH, Soltys K, Sindhi RK, Bond G, Mazariegos GV, Green M. Chronic high Epstein–Barr viral load carriage in pediatric small bowel transplant recipients.Pediatr Transplantation 2010: 14:549–553. © 2010 John Wiley & Sons A/S. Abstract: The development of EBV infection and PTLD is normally associated with a high EBV load in peripheral blood. Often, children undergoing primary or reactivation of EBV infection subsequent to ITx will have chronically elevated EBV loads. To better understand this phenomenon and its consequences, we retrospectively reviewed the records of children who underwent ITx (either isolated or part of multivisceral transplantation) at our center from 1992 to 2007, to identify chronic high EBV load carriers in this population. CHL state was defined as the presence of high load for >50% of samples for greater than or equal to six months following either asymptomatic infection or complete clinical resolution of EBV disease/PTLD. Thirty‐five CHL carriers were identified from our patient population. Pretransplant serologies were available on 34 of these patients: 17 were EBV negative and 17 seropositive; one had unknown EBV serostatus prior to transplant. Seven of the 17 seronegative patients developed their CHL carrier state at the time of their primary EBV infection. Thirteen of the 35 (37%) HLC patients developed EBV disease after meeting the definition of high‐load carrier states. EBV‐related diseases developing in CHL carriers included EBV adenitis (n = 1), EBV enteritis (n = 7), PTLD (n = 4), and EBV+ spindle cell tumor (n = 1). Disease was seen in 7/17 of the seronegative (one PTLD) and 6/17 of the seropositive patients (three PTLD). Thirteen of 35 patients (37%) resolved their CHL state without apparent sequelae while nine remain asymptomatic CHL carriers. Three children have had more than one episode of CHL. These data provide important information about the outcome of chronic EBV high‐load carriage in pediatric intestinal transplant recipients. 相似文献
1000.
Baker M Anderson JK Jaffer O Trimmer C Cadeddu JA 《Journal of endourology / Endourological Society》2007,21(6):606-609
BACKGROUND AND PURPOSE: Most patients have minimal pain after percutaneous radiofrequency ablation (RFA) of a renal tumor. However, anecdotally, there is some variation in the amount of patient discomfort. Our goal was to identify relevant patient factors and characteristics of their renal tumors that may influence pain after percutaneous RF ablation. PATIENTS AND METHODS: We performed a retrospective chart review of 59 sequential patients who received percutaneous RFA between 2001 and 2005 at a single institution. Data on patient age, sex, body mass index (BMI), and narcotic administration in the periprocedural period were available for 46 patients. Preoperative imaging (CT or MRI) was reviewed to determine tumor size and location, as well as the shortest distance of the mass to the body-wall musculature. RESULTS: The distance from the renal mass to the body-wall musculature was significantly correlated with the total narcotics received in the periprocedural period. This measured distance did not correlate with the patient's BMI. No other relations between patient factors or tumor characteristics and peri-procedural narcotic usage were identified. CONCLUSION: Patients whose tumors lie close to their body-wall musculature have greater narcotic requirements in the periprocedural period. Knowledge of this correlation should result in better patient counseling and help anticipate periprocedural analgesia requirements. 相似文献