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101.
An eight-channel stimulation system, currently intended for stimulation of lower extremities, was developed and is introduced. The major development goals were easy handling, modularity to make the system easily adaptable for other functional electrical stimulation (FES) applications, and a wide stimulation parameter range for application-specific parameter optimization. For paraplegic stepping, the system worn by the patient consists of 2 four-channel stimulation modules, a central unit holding the battery and circuitry for power management and communication control, a wireless remote control unit, and a palmtop computer as the main control and input device. A software package for Microsoft Windows supports the design and optimization of stimulation sequences in the rehabilitation center. First tests with patients familiar with FES showed smoother movements during stepping and acceptable good handling. In combination with the PC software, the required stimulation sequences could be created in a very short time.  相似文献   
102.
INTRODUCTION: Choosing surgery as a career is declining among U.S. medical students. The 8-wk third year surgery clerkship at our institution can be an intense learning experience, and we hypothesized that during this clerkship medical student quality-of-life would drop significantly from baseline, and that this drop would be greater among certain subgroups, such as women students not interested in pursuing a surgical career, and those who place a high value on a controllable lifestyle. METHODS: At clerkship orientation (baseline), students were asked to complete a survey that measured quality-of-life on an 84-point scale, and depression on a 40-point scale. The quality-of-life scale was composed of select questions from the Medical Outcomes Study, and the Harvard Department of Psychiatry/NDSD brief screening instrument was used to measure depression. Students were also asked the typical number of hours they slept per night. Demographics, attitude toward a controllable lifestyle, and top three specialties of interest were also gathered at baseline. On week 6 of the clerkship, students were surveyed on the same quality-of -life and depression scales, and asked average hours of sleep per night for the previous week. RESULTS: From June 2005 through December 2006, 143 of 177 (81%) students agreed to participate, and after exclusions for missing data, 137 students were included in the analysis. Sixty-nine students were women (51%), and the average age was 25.8 (sd 2.6). Mean quality-of-life at baseline was 57.0 (sd 11.3) and at week 6 was 50.4 (sd 10.1) representing a statistically significant average decline of 6.6 points (P < 0.0001). Mean depression at baseline was 14.4 (sd 3.8) and at week 6 was 15.1 (sd 3.6), representing a small but significant average decline of 0.7 points (P = 0.0155). Mean sleep at baseline was 6.3 h/night (sd 0.9) and at week 6 was 5.7 h/night (sd 1.2), representing a statistically significant average decline of 0.6 h/night (P < 0.0001). Declines were similar on all outcomes between men versus women, those who ranked surgery in their top three career choices versus those who did not, and those who ranked controllable lifestyle as "very important" versus all other categories. CONCLUSION: Quality-of-life and sleep declines and depression increases significantly in third-year medical students from orientation to week 6 of their surgery clerkship at our institution. We look forward to studying quality-of-life on other clerkships for comparison, assessing whether the magnitude of this decline in quality-of-life predicts students avoiding a future career in surgery, and testing interventions to prevent this decline in quality-of-life during the clerkship.  相似文献   
103.
BACKGROUND: We have demonstrated that pyridoxal 5'-phosphate (PLP), an active form of vitamin B6, inhibits formation of advanced glycation end-products (AGEs) by trapping 3-deoxyglucosone. The present study aimed to clarify if PLP could exert beneficial effects on nephropathy in diabetic rats. METHODS: Streptozotocin (STZ)-induced diabetic rats were treated by oral administration of PLP or pyridoxamine (PM), another active form of vitamin B6, at a dose of 600 mg/kg/day for 16 weeks. AGEs [imidazolone, N(epsilon)-(carboxymethyl)lysine (CML) and N(2)-carboxyethyl-2'-deoxyguanosine (CEdG)], transforming growth factor-beta1 (TGF-beta1), type 1 collagen and fibronectin were detected in the kidneys using immunohistochemistry. Gene expression of TGF-beta1 and receptor for AGEs (RAGEs) in the kidneys was determined using real-time quantitative polymerase chain reaction. RESULTS: Administration of PLP significantly inhibited albuminuria, glomerular hypertrophy, mesangial expansion, and interstitial fibrosis as compared with diabetic rats. PLP markedly inhibited accumulation of AGEs such as imidazolone, CML and CEdG, a DNA-linked AGE, in glomeruli. PLP significantly inhibited expression of TGF-beta1, type 1 collagen, fibronectin and RAGE in the kidneys. PLP was superior to PM in inhibiting accumulation of AGEs, expression of TGF-beta1, type 1 collagen, and fibronectin, and the development of diabetic nephropathy. CONCLUSIONS: PLP prevented progression of nephropathy in STZ-induced diabetic rats by inhibiting formation of AGEs. PLP is considered a promising active form of vitamin B6 for the treatment of AGE-linked disorders such as diabetic nephropathy.  相似文献   
104.
105.

Introduction

The purpose of this study was to evaluate the impact of computed tomography scanning on the inter- and intra-observer reliability of the OTA/AO, the Schatzker, and the Hohl classifications in the assessment of tibial plateau fractures.

Methods

Four independent observers classified 45 consecutive fractures of the tibial plateau according to the criteria of the OTA/AO system, the Schatzker classification, and the Hohl classification. Two sessions of readings were compared; first, the use of plain anterior-posterior and lateral X-rays alone was evaluated, then 4 weeks later the combination of plain X-rays and two-dimensional computed tomography scans were evaluated. The readings were repeated 8 weeks later to evaluate intra-observer reliability.

Results

The three classification systems showed “moderate” inter-observer reliability and “good” and “moderate” intra-observer reliability when classified solely on the basis of plain radiographs. After the addition of computed tomography scans inter-observer reliability significantly improved to “good” in all classifications. Likewise, intra-observer reliability improved to “good” in all classifications after the addition of CT-scans. Statistical analysis showed no significant difference regarding inter- and intra-observer agreement between the three classifications.

Conclusions

Computed tomography scanning improved the inter- and intra-observer reliability of the OTA/AO, the Schatzker, and the Hohl classification. Overall, all three classification systems showed “good” inter- and intra-observer reproducibility when classified with CT-scans.  相似文献   
106.
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108.
Transient osteoporosis of the hip is an uncommon disorder of unclear etiology. It is often confused with other diagnosis including osteonecrosis of the femoral head. Authors describe a case of transient osteoporosis of the hip of 32 years woman. The symptoms occurred in third trimester of pregnancy. The primary symptoms were right hip pain and decreased range of motion of the right hip. In diagnostic process helpful were clinical examination, X-ray, ultrasonography, MRI and microscopic examination. As a treatment authors used walking on crutches, calcitonin and calcium preparate. After a few months remission of symptoms and normalization in accessory investigations were obtained.  相似文献   
109.
Smith MR  Boyce SP  Moyneur E  Duh MS  Raut MK  Brandman J 《The Journal of urology》2006,175(1):136-9; discussion 139
PURPOSE: We assessed the relationship between GnRH agonists and the risk of clinical fractures in men with prostate cancer. MATERIALS AND METHODS: Using a database of medical claims from 16 large American companies we identified a study group of 3,779 men with prostate cancer who received treatment with a GnRH agonist and a control group of 8,341 with prostate cancer who were not treated with a GnRH agonist. Men with 1 or more medical claims for bone metastases were excluded. The rates of any clinical fracture, hip fracture and vertebral fracture were compared between the groups. RESULTS: The rate of any fracture was 7.91/100 vs 6.55/100 person-years at risk in men who received vs did not receive a GnRH agonist (relative risk 1.21, 95% CI 1.09 to 1.34). The rates of hip fracture (relative risk 1.76, 95% CI 1.33 to 2.33) and vertebral fracture (relative risk 1.18, 95% CI 0.94 to 1.48) were also higher in men who received a GnRH agonist. GnRH agonist treatment was independently associated with fracture risk on multivariate analyses. CONCLUSIONS: GnRH agonists increase the risk of clinical fracture in men with prostate cancer.  相似文献   
110.
The goal of the study was to evaluate the long-term results of a metal-on-metal articulation. We evaluated the results and histologic findings in patients who had undergone revision. One hundred total hip arthroplasties with a Lubrimet metal-on-metal articulation (Smith and Nephew, Rotkreuz, Switzerland) were implanted in 99 consecutive unselected patients in 1995 and 1996, and the results were prospectively analyzed up to a mean of 126 months postoperatively. Periprosthetic tissues of all 6 hips that had undergone revision because of aseptic loosening, mechanical failure, or periprosthetic fracture showed metallosis and extensive lymphocytic and plasma cell infiltration around the metal debris. With removal of the component because of aseptic loosening as the end point, survivorship was 98% for the stem and 96% for the cup.  相似文献   
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