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21.
Visual impairment is an important risk factor for falls. However, relatively little is known about how visual impairment affects stair or step negotiation. The aim of the present study was to determine the effects of blurred vision on the mechanics of landing during stepping down by the elderly. Twelve elderly subjects (72.3 +/- 4.7 year) stepped down from three levels (7.2 cm, 14.4 cm and 21.6 cm). Step execution time, ankle and knee joint angular displacements at the instance of ground contact, and vertical landing stiffness and the amount of bodyweight supported by the contralateral (support) limb during the initial contact period were recorded. Measurements were repeated with vision blurred by light scattering lenses. With blurred vision, step execution time increased (P < 0.05), knee flexion and ankle plantar-flexion increased (P < 0.05), vertical stiffness decreased (P < 0.01), and the amount of bodyweight being supported by the contralateral leg increased (P < 0.05). These findings suggest that under conditions of blurred vision, subjects were more cautious and attempted to 'feel' their way to the floor rather than 'drop' on to it. This may have been an adaptation to increase the kinaesthetic information from the lower limb to make up for the unreliable or incomplete visual information. Correcting common visual problems such as uncorrected refractive errors and cataract may be an important intervention strategy in improving how the elderly negotiate stairs.  相似文献   
22.
BACKGROUND: A minimally invasive endoscopic approach for the management of sinonasal malignancy offers several advantages including excellent illumination, maximal preservation of uninvolved vital structures, and sparing of facial incisions. The purpose of this study was to evaluate the outcome and morbidity of endoscopic resection with or without combined radiotherapy and/or chemotherapy. METHODS: Forty-seven patients with sinonasal malignancy were diagnosed and/or treated with an endoscopic approach at The Cleveland Clinic Foundation and The University of Pennsylvania Medical Center from 1996 to 2003. Nineteen patients fulfilled the study criteria and had a minimally invasive endoscopic resection. Fifteen patients were treated with curative intent and four patients underwent palliative resection. RESULTS: The mean age was 56.9 (9-78 years) years and the mean follow-up period was 26.4 months. Combined radiation with or without chemotherapy pre- or postoperatively was given to 15 of 19 (78.9%) patients. Thirteen patients were resected strictly with an endoscopic approach and six patients were resected in combination with neurosurgery. There were no peri- and postoperative deaths. The local recurrence (LR) rate was 26.3% (5/19) and the distant metastasis rate was 15.8% (3/19). Overall survival rate (OS) was 78.9% (15/19) at a mean follow-up duration of 32.1 (4-74 months) months. The disease-free survival (DFS) rate was 68.4% (13/19) by clinical, endoscopic, and radiographic surveillance at a mean follow-up duration of 33.1 months. Patients treated with curative intent had LR, OS, and DFS rates of 21.4, 85.7, and 85.7%, respectively, and the patients treated for palliation had LR, OS, and DFS rates of 40, 60, and 15%, respectively. CONCLUSION: Minimally invasive endoscopic resection of sinonasal malignancy in combination with adjunctive therapies reduces treatment morbidity and yields LR, OS, and DFS rates that are comparable with traditional anterior craniofacial approaches.  相似文献   
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OBJECTIVE: The purpose of this study was to collect data about the incidence of high-risk HPV (16, 18, 33) types in in situ cervical cancers, and to evaluate the reliability of the morphological signs of HPV infection by comparing the presence of these signs to the PCR-proven HPV virus infection. METHODS: Fifty patients who underwent conisation at the Department of Obstetrics and Gynecology of Semmelweis University, Budapest, Hungary because of in situ cervical cancer were examined retrospectively for the presence of HPV infection by the PCR technique. The direct and indirect morphological signs of HPV infection identified in the histological and cytological samples were compared to the actual results of virus DNA amplification by PCR in the identical histological sections. The evaluation of the cytological smears and the histological sections was accomplished independently by two different pathologists. RESULTS: E6 open reading frame of HPV 16, 18 or 33 was detected by PCR in 56% (28 cases) of the histological sections of the 50 examined patients with in situ cancer. In 92% (26 patients) of the 28 HPV positive patients one HPV type was detected, while in one of the remaining two cases two HPV types (16/33), or all three types could be detected. The direct morphological signs for HPV infection proved to be 75% sensitive and 50% specific when compared to the results of PCR. Their predictive value for HPV infection was 65%. For the indirect HPV signs the sensitivity was 64% and specificity 31%. The predictive value, prognosticating the presence of HPV 16, 18, 33 infection was 54% in the same sections. Using significance analysis no significant relationship (p = 0.7728) could be detected between the positivity of indirect signs and the presence of HPV 16, 18, 33 infection, while in case of direct signs the relationship was almost significant (p = 0.0675). The joint testing of the direct and indirect signs did not improve the results (p = 0.1338). During the review of the cytological smears the specificity of the cytology in predicting true HPV infections was found to be 68% and sensitivity was 20%. The predictive value was only 50%. A significance analysis was not accomplished by this diagnostic method because of the missing data (see text). CONCLUSION: The method of Nawa et al. seems to be a reliable approach for the detection of HPV DNA in paraffin-embedded material. The three main types of HPV (16, 18, 33) are probably represented in lower percentages in CIN III in Hungary, but a larger survey is needed to obtain reliable data. The direct and indirect morphological signs of HPV infection failed to show a significant relationship with the PCR proven presence of HPV 16, 18, 33.  相似文献   
25.
Promoter hypermethylation of cyclooxygenase-2 in gastric carcinoma   总被引:5,自引:0,他引:5  
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26.
Although many occupational safety programs are targeted toward large firms, the construction industry is dominated by smaller firms. This study examines the differential effect of firm size on the risk and the reporting of over 3000 serious and minor nonfatal elevation fall injuries in Danish construction industry trades (1993 to 1999). Small firms (<20 employees) accounted for 93% of all firms and 55% of worker-years. There was an inverse relationship between firm size and serious injury rates and a direct relationship between firm size and minor injury rates. An inverse relationship between firm size and injury severity odds ratios (serious versus minor) was found for carpentry, electrical work, general contracting, and the remaining other trades. Health and safety issues, legislation, and enforcement in the construction industry should, to a greater degree, be focused on smaller firms.  相似文献   
27.
BACKGROUND: The pattern of renal transplantation has never been described since the introduction of the technique. The purpose of this study was therefore to characterise the pattern of renal transplantation from 1967 to 2000, focusing on renal graft function as a predictor of survival. METHODS: This study was a retrospective analysis of an electronic database. The setting was a single renal transplant centre in the United Kingdom covering a population of 2.2 million and included patients who received at least one renal transplant over the study period (n = 1516). The main outcome measures were patient and graft survival, acute rejection episodes and patterns of graft function, as measure by creatinine levels. RESULTS: There were 559 (36.8%) female patients; 109 (7.2%) patients had pre-existing diabetes. Patient survival was adversely affected by increased age at transplant (p < 0.001): 5-year patient survival from first transplant was 82% for patients aged 0 to 17 years, 80% for 18 to 49 years and 61% for > 49 years. Pre-existing diabetes also adversely affected survival (p < 0.01): 5-year graft survival was 63% for patients with diabetes versus 74% for those without. Graft survival was significantly associated with serum creatinine levels recorded 1 year post-primary transplant (p < 0.001) and with three or more acute rejection episodes (p < 0.05). Neither gender nor diabetes status were statistically significant in predicting graft survival. The number of acute rejection episodes was significantly greater in patients with pre-existing diabetes than those without (61% versus 42%, respectively; p < 0.001). There were no differences in the number of acute rejection episodes occurring across age groups. CONCLUSION: Patient and graft survival improved markedly over the 34-year study period, although patient survival has changed little since 1990. Serum creatinine levels are a reliable predictor of graft survival.  相似文献   
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Lake Champlain continues to experience mercury contamination resulting in public advisories to limit human consumption of top trophic level fish such as walleye. Prior research suggested that mercury levels in biota could be modified by differences in ecosystem productivity as well as mercury loadings. We investigated relationships between mercury in different trophic levels in Lake Champlain. We measured inorganic and methyl mercury in water, seston, and two size fractions of zooplankton from 13 sites representing a range of nutrient loading conditions and productivity. Biomass varied significantly across lake segments in all measured ecosystem compartments in response to significant differences in nutrient levels. Local environmental factors such as alkalinity influenced the partitioning of mercury between water and seston. Mercury incorporation into biota was influenced by the biomass and mercury content of different ecosystem strata. Pelagic fish tissue mercury was a function of fish length and the size of the mercury pool associated with large zooplankton. We used these observations to parameterize a model of mercury transfers in the Lake Champlain food web that accounts for ecosystem productivity effects. Simulations using the mercury trophic transfer model suggest that reductions of 25–75% in summertime dissolved eplimnetic total mercury will likely allow fish tissue mercury concentrations to drop to the target level of 0.3 μg g−1 in a 40-cm fish in all lake segments. Changes in nutrient loading and ecosystem productivity in eutrophic segments may delay any response to reduced dissolved mercury and may result in increases in fish tissue mercury.  相似文献   
30.
Samarium-153 lexidronam (153Sm-EDTMP) is FDA approved for painful osteoblastic bone metastases that image on bone scan. 153Sm-EDTMP decay has a therapeutic beta-emission and a gamma-photon for bone scan imaging. Monitoring of osteosarcoma radiation treatment effectiveness was performed with bone, CT, MRI and PET/CT fusion imaging. Bone scan and PET/CT improved in 5 out of 9 and 16 out of 18 osteosarcoma sites, respectively. 153Sm-EDTMP targets multiple sites of disease, with a single administration. Side effects of 153Sm-EDTMP (0.5-2.5 mCi/kg) have been minimal and include transient thrombocytopenia and neutropenia. 153Sm-EDTMP can be combined with radiation therapy, bisphosphonates and/or chemotherapy to synergistically improve palliation. This article reviews the rationale, indications and monitoring of standard-dose samarium and investigational high-dose 153Sm-EDTMP treatment of cancer involving bone.  相似文献   
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