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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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The 1990 general practitioners (GPs) contract introduced item of service payment for minor surgery, payable for six categories of procedure. Early review showed no substitution of cheaper procedures for more expensive treatments. Detailed payment data from six Health Authorities for the period 1993-2000 show an 11 per cent increase in claims, largely accounted for by the rise in cautery, incorporating cryotherapy. Cryotherapy is no more effective at treating warts than cheap commercially available products, but is quite profitable for GPs. This is yet another example of item of service payment distorting treatment priorities. The new GP contract, and the initiative to develop GPs with special interests in dermatology and minor surgery, will allow primary care trusts to develop minor surgery undertaken by appropriately skilled and experienced GPs, and which reflects the needs of the population.  相似文献   
25.
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   
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27.
Promoter hypermethylation of cyclooxygenase-2 in gastric carcinoma   总被引:5,自引:0,他引:5  
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28.
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   
29.
It has long been assumed that Ehrlichia chaffeensis (Anderson, Dawson & Wilson), is not transmitted transovarially in the lone star tick vector Amblyomma americanum (L.). To test this hypothesis, three beagle dogs, Canis familiaris (L.) (Carnivora: Canidae), were subcutaneously infected with E. chaffeensis (Arkansas strain). Uninfected nymphal lone star ticks were placed on the infected dogs and allowed to feed to repletion. These nymphal ticks were allowed to molt, and five of five adult female ticks sampled were confirmed to be infected by polymerase chain reaction (PCR). Forty infected adult ticks, the majority of which were female with several males included to stimulate feeding, were then placed on two uninfected dogs. Fourteen females were removed early and the rest were allowed to feed to repletion. After feeding to repletion, the six remaining females detached and two of these females were tested preoviposition, whereas the remaining four were allowed to lay eggs. All six of these fully engorged females tested negative by PCR. The egg clutches laid by four engorged adult females, and the larvae that hatched from these eggs along with larvae from a previously untested egg clutch, were shown to be uninfected by PCR. This seems to support the long-held assumption of lack of transovarial transmission. Also of interest, we found that these PCR-confirmed infected adult ticks reared in the laboratory did not transmit E. chaffeensis to uninfected dogs.  相似文献   
30.
Introduction: Ocular hypertension in open-angle glaucoma is caused by a reduced rate of removal of aqueous humour (AH) from the eye, with the majority of AH draining from the anterior chamber through the conventional outflow pathway, comprising the trabecular meshwork (TM) and Schlemm’s Canal. Resistance to outflow is generated, in part, by the extracellular matrix (ECM) of the outflow tissues. Current pressure-lowering topical medications largely suppress AH production, or enhance its clearance through the unconventional pathway. However, therapies targeting the ECM of the conventional pathway in order to decrease intraocular pressure have become a recent focus of attention.

Areas covered: We discuss the role of ECM of the TM in outflow homeostasis and its relevance as a target for glaucoma therapy, including progress in development of topical eye formulations, together with gene therapy approaches based on inducible, virally-mediated expression of matrix metalloproteinases to enhance aqueous outflow.

Expert opinion: There remains a need for improved glaucoma medications that more specifically act upon sites causative to glaucoma pathogenesis. Emerging strategies targeting the ECM of the conventional outflow pathway, or associated components of the cytoskeleton of TM cells, involving new pharmacological formulations or genetically-based therapies, are promising avenues of future glaucoma treatment.  相似文献   

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