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951.
Over the last 20 years, a great many innovations have been introduced that are designed to reduce laborious activities; however, an unexpected consequence of these developments is a trend toward a sedentary lifestyle and prolonged static postures that are accompanied by musculoskeletal disorders (MSDs). MSDs have become a major issue of concern because the afflictions can be severe enough to disable professional careers. Although clinical dentistry is a field with immense potential for MSDs, only a few studies have investigated this issue. The present study was carried out addressing prevalence and awareness level of MSDs among 500 dental professionals from Central India. Also, the interrelationship between practices of working postures with occurrence of pain in different body parts were assessed using a structured questionnaire format. The results were statistically significant, and indicated that the prevalence of MSDs is high and that there is a dire need to enhance awareness regarding correct working postures. This study encompassed all factors that can be addressed as causes for MSDs among dentists.  相似文献   
952.
Background: Many reports have described that individuals with Alzheimer’s disease show neural breakdown in the brainstem nuclei, hippocampus and auditory cortex in the temporal lobe of the brain. However, it is still unclear whether auditory skills mediated by these areas differ across individuals with and without Alzheimer’s disease and how these auditory skills are further confounded by reduction in cognitive function in individuals with AD.Aim: The aim of this study is to discover the hidden and nonlinear associations among higher-order auditory and cognitive processes in individuals with and without Alzheimer’s disease through artificial neural network analysis.Methods: The analyses were based on auditory test data obtained from nine clinically confirmed Alzheimer’s disease cases and nine age-matched controls. Hearing threshold sensitivity was equivalent across groups, indicating similar peripheral auditory function. Auditory function was evaluated by standardized tests of auditory closure, auditory attention, and auditory figure ground in listeners with and without Alzheimer’s disease. The inputs used for analyses were cognitive status and auditory function. The dependent variables were RAU scores computed from scores of auditory tests.Results: Artificial neural networks showed a complex relationship between the input variables (cognitive status and auditory function) that cannot be predicted simply on the basis of cognition differences between individuals with and without Alzheimer’s disease.Conclusion: The results of this study suggest that central auditory function declines with age, regardless of changes in cognitive function.  相似文献   
953.
KCNQ2/3 voltage-gated potassium channels conduct low-threshold, slowly activating and non-inactivating currents to repolarize the neuronal resting membrane potential. The channels negatively regulate neuronal excitability and KCNQ2/3 openers are efficacious in hyperexcited states such as epilepsy and pain. We developed and utilized thallium influx assays to profile novel KCNQ2/3 channel openers with respect to selectivity across KCNQ subtypes and on requirement for tryptophan 236 of KCNQ2, a critical residue for activity of the KCNQ opener retigabine. Using distinct chemical series of openers, a quinazolinone series showed relatively poor selectivity across multiple KCNQ channels and lacked activity at the KCNQ2(W236L) mutant channel. In contrast, several novel benzimidazole openers showed selectivity for KCNQ2/3 and KCNQ2 and retain activity at KCNQ2(W236L). Profiling of several hundred KCNQ2/3 openers across multiple diverse chemical series revealed that openers show differential degrees of selectivity across subtypes, with selectivity most difficult to achieve against KCNQ2. In addition, we report the significant finding that KCNQ openers can pharmacologically differentiate between homomeric and heteromeric channels containing subtypes in common. Moreover, most openers assayed were dependent on the W236 for activity, whereas only a small number appear to use a distinct mechanism. Collectively, we provide novel insights into the molecular pharmacology of KCNQ channels by demonstrating differential selectivity and site of action for KCNQ2/3 openers. The high-throughput thallium influx assays should prove useful for rapid characterization of KCNQ openers and in guiding efforts to identify selective compounds for advancement towards the clinic.  相似文献   
954.
Pilomyxoid astrocytoma (PMA) is a recently described neoplasm. PMA shares few features with pilocytic astrocytoma (PA), the most common central nervous system (CNS) tumor in the pediatric population, yet displays histological differences. Previous studies have shown that PMAs have more aggressive biological behavior as compared to PA. These findings suggest that PMA may be a unique and distinct neoplasm. We report a pilomyxoid astrocytoma of the hypothalamic-chiasmatic region with leptomeningeal dissemination in a 3-month old infant. This case report discusses the histological, clinical, and radiographic characteristics of PMA. In addition, the current treatment options and research potential involving this disease are also briefly described.  相似文献   
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Papillary tumors of the pineal region (PTPRs) are rare and are recognized as a distinct entity in the recent 2007 World Health Organization (WHO) classification of tumors of nervous system. Till date, only 55 cases have been reported. We report another three patients of PTPRs with characteristic radiological features. Histologically, all the three patients exhibited remarkable uniform histology of epithelioid morphology with variable presence of single to multilayered papillary architecture. Consistent absence of fibrillary matrix was noted in all the three cases. None of the cases showed aggressive histology. A large multicenter study is essential for upfront characterizing the biological behavior, as frequency of these tumors is very low.  相似文献   
959.
Sleep and Breathing - A close association of oxidative stress (OS) and ischemia-modified albumin (IMA) with obstructive sleep apnea (OSA) has been reported in the literature, but the results on IMA...  相似文献   
960.
Knee arthrodesis is most commonly performed for failed total knee arthroplasty. Conventional arthrodesis techniques are associated with a high incidence of complications and are unsuitable in cases with extensive bone loss. We report our medium-term results using a custom-made cemented knee arthrodesis prosthesis in 10 patients with a mean follow-up of 56.4 months (range, 15-199 months). The prosthesis was implanted as a 1- or 2-stage procedure for infected revision knee arthroplasty or tumor endoprosthesis in 9 patients and as a primary procedure in 1 patient with angiosarcoma involving the knee extensor mechanism. The average combined femoral and tibial bone deficit was 170 mm (range, 56-220 mm). Implant survivorship was 90%. All patients with retained prosthesis had no evidence of residual infection or loosening and were able to mobilize independently. One prosthesis was revised though retained following a prosthetic fracture, and 1 patient underwent above-knee amputation for uncontrolled infection. We conclude that the Stanmore knee arthrodesis prosthesis provides reliable fusion in an otherwise difficult-to-treat group of patients.  相似文献   
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