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151.
Sue Lord Lynn Rochester Vicki Hetherington Liesl M. Allcock David Burn 《Gait & posture》2010,31(2):169-174
Motor and cognitive processes are required for successful ‘real world’ walking. We explored the specific contribution of motor function, executive function, and attention to functional gait performance in people with Parkinson's Disease (PD) when ‘off’ medication. Twenty-nine people with PD wearing an accelerometer were tested in their home whilst walking under four task conditions. Explanatory characteristics included age, motor function, executive function, sustained attention and divided attention. Repeated measures ANOVA compared gait speed under different task conditions. Multiple regression analysis explored the effect of characteristics on gait speed and gait interference (difference between dual and single task). Gait performance deteriorated under complex conditions (F = 51.0, P < .001). Motor function and attention explained up to 65% variance in gait speed. Motor function, attention and executive function explained up to 66% variance in gait interference. Sustained attention explained up to 10% variance in gait speed; executive function explained up to 21% variance in gait interference and divided attention explained up to 22% variance in gait interference. Motor function, executive function and attention contribute to gait speed and gait interference in PD during a functional walking task whilst ‘off’ medication. When both executive function and attention are included as explanatory variables, attention discriminates gait performance more effectively. Whilst both contribute to functional gait, they are used selectively to optimise performance for different conditions and to meet complex task requirements. 相似文献
152.
LM Paes da Silva Ramos Fernandes R Ordinola-Zapata MA Húngaro Duarte AL Alvares Capelozza 《Dento maxillo facial radiology》2013,42(1):80179163
Objectives
The aim of this study was to determine the prevalence of apical periodontitis (AP) detected in cone beam CT (CBCT) images from a database.Methods
CBCT images of 300 Brazilian patients were assessed. AP images were measured in three dimensions. Age, gender, number and location of total teeth in each patient were considered. AP location was considered according to tooth groups. The extent of AP was determined by the largest diameter in any of the three dimensions. Percentages and the χ2 test were used for statistical analysis.Results
AP was found in 51.4% of the patients and in 3.4% of the teeth. Higher prevalence of AP was found in 60- to 69-year-olds (73.1%) and in mandibular molars (5.9%) (p < 0.05). Inadequate endodontic treatment presented higher prevalence of AP (78.1%).Conclusions
AP can be frequently found in CBCT examinations. The presence of AP has a significant association with patients'' age, and tooth type and condition. CBCT databases are useful for cross-sectional studies about AP prevalence in a population. 相似文献153.
María Clara Restrepo-Méndez Aluísio JD Barros Kerry LM Wong Hope L Johnson George Pariyo Giovanny VA Fran?a Fernando C Wehrmeister Cesar G Victora 《Bulletin of the World Health Organization》2016,94(11):794-805B
ObjectiveTo investigate disparities in full immunization coverage across and within 86 low- and middle-income countries.MethodsIn May 2015, using data from the most recent Demographic and Health Surveys and Multiple Indicator Cluster Surveys, we investigated inequalities in full immunization coverage – i.e. one dose of bacille Calmette-Guérin vaccine, one dose of measles vaccine, three doses of vaccine against diphtheria, pertussis and tetanus and three doses of polio vaccine – in 86 low- or middle-income countries. We then investigated temporal trends in the level and inequality of such coverage in eight of the countries.FindingsIn each of the World Health Organization’s regions, it appeared that about 56–69% of eligible children in the low- and middle-income countries had received full immunization. However, within each region, the mean recorded level of such coverage varied greatly. In the African Region, for example, it varied from 11.4% in Chad to 90.3% in Rwanda. We detected pro-rich inequality in such coverage in 45 of the 83 countries for which the relevant data were available and pro-urban inequality in 35 of the 86 study countries. Among the countries in which we investigated coverage trends, Madagascar and Mozambique appeared to have made the greatest progress in improving levels of full immunization coverage over the last two decades, particularly among the poorest quintiles of their populations.ConclusionMost low- and middle-income countries are affected by pro-rich and pro-urban inequalities in full immunization coverage that are not apparent when only national mean values of such coverage are reported. 相似文献
154.
OBJECTIVE: To investigate the cancer-promoting effect of Taiwan betel quid in hamster buccal pouch carcinogenesis.
MATERIALS AND METHODS: Two hundred and fifty-two non-inbred mate adult Syrian golden hamsters were randomly divided into six groups, each containing forty-two animalS. A treatment regimen over a 14-week experimental period was employed with six animals per group being killed at seven different periods (every 2 weeks). The right buccal pouch of each animal was painted three times a week with various combinations of 7, 12-dimethylbenz[a]anthracene (DMBA), Taiwan betel quid extract, dimethyl sulfoxide (DMSO) and mineral oil.
RESULT: Both the number and size of tumors in animals concurrently treated with DMBA and betel quid were significantly higher than those in animals treated with DMBA alone in each killing period of 8, 10, 12 and 14 weekS. No visible tumors but hyperkeratosis and acanthosis were observed in pouches treated with betel quid alone for all killing periods.
CONCLUSION: Our results indicate Taiwan betel quid may be a co-carcinogen in human oral carcinogenesis, if extrapolation can be made from the current animal study. 相似文献
MATERIALS AND METHODS: Two hundred and fifty-two non-inbred mate adult Syrian golden hamsters were randomly divided into six groups, each containing forty-two animalS. A treatment regimen over a 14-week experimental period was employed with six animals per group being killed at seven different periods (every 2 weeks). The right buccal pouch of each animal was painted three times a week with various combinations of 7, 12-dimethylbenz[a]anthracene (DMBA), Taiwan betel quid extract, dimethyl sulfoxide (DMSO) and mineral oil.
RESULT: Both the number and size of tumors in animals concurrently treated with DMBA and betel quid were significantly higher than those in animals treated with DMBA alone in each killing period of 8, 10, 12 and 14 weekS. No visible tumors but hyperkeratosis and acanthosis were observed in pouches treated with betel quid alone for all killing periods.
CONCLUSION: Our results indicate Taiwan betel quid may be a co-carcinogen in human oral carcinogenesis, if extrapolation can be made from the current animal study. 相似文献
155.
李颖 《中国感染与化疗杂志》2010,10(1):43-43
肠杆菌科细菌对碳青霉烯类抗生素的耐药性可以由过量产生AmpC酶且同时外膜孔道蛋白大量缺失和(或)外排泵过量表达,或产生能水解碳青霉烯类的β内酰胺酶引起。这些碳青霉烯酶可以分为金属β内酰胺酶(MSL)和丝氨酸碳青霉烯酶两类。替加环素是一类半合成的甘氨酰环素类抗菌药物,对其他类抗生素耐药的细菌通常对替加环素无交叉耐药。 相似文献
156.
自1987年以来,NMDP有效推动了儿童无关供者造血干细胞移植(HCT)的发展.在庆祝NMDP成立20周年之际,本文就儿童急性白血病患者移植所取得的成果和经验加以总结,目的在于进一步提高移植疗效,把握未来研究方向. 相似文献
157.
158.
159.
继续医学教育的目的是通过向医生提供最新的医学知识和技能,使医生在其整个职业生涯中,一直保持较高的医疗水平.但目前还没有充足的证据能证明继续医学教育活动的有效性,以及在继续医学教育活动中哪些教育方法和技术能最有效地传播和记忆医学知识.为了全面、系统地评估继续医学教育活动的有效性,以及了解不同的教育手段对医生知识、态度、技能、临床表现和临床效果的作用.美国约翰·霍普金斯大学医学院、美国医疗保健研究与质量管理署和美国胸科医师学会的专家共同进行了一项系统回顾性研究. 相似文献
160.
样品固相净化及反相高效液相色谱法测定血浆中茶碱 总被引:1,自引:0,他引:1
本文用氧化铝固相净化血样以消除血中杂质及某些合并用药的干扰,用Zorbax-C18柱及甲醇-(0.05 mol/L)醋酸钠缓冲液(50:50)为流动相,254 nm波长检测,咖啡因为内标测定了茶碱人体血浆浓度的变化。该法样品处理简便、快速,净化回收率好(80~86%)茶碱的检测限为0.2ng(信噪比3),在血浆中的最低检测浓度为20 ng/ml。标准曲线r为0.9995,日内变异系数1.89%,日间变异系数为2.41%,方法平均回收率为98.44±0.89%。 相似文献