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81.
Petrofsky JS Bweir S Andal A Chavez J Crane A Saunders J Laymon M 《European journal of applied physiology》2004,92(3):254-262
Forty-four male and female subjects with no history of falling and whose ages ranged from 10 to 68 years participated in a series of experiments to assess movement at the joints during gait while walking in a straight line, in pivot turns and in turns of 0.33 and 0.66 m diameter. Acceleration at the joints in the forward and side-to-side direction was measured by dual-axis accelerometers placed at the ankles, knees, hips, shoulders, and on the head. Eye movement was assessed from electrodes placed on the sides of the eyes. The results of the experiments showed that for people whose age was above 40 years, significant increases in the forward-back and side-to-side movements occurred at all joints and progressively increased with age. By age 60, adverse movement of the joints as much as quadrupled in many subjects when compared to people whose age was 20–30 years. The increase in joint acceleration occurred equally in the front-back and side-to-side planes. The mechanism of the increased joint movement may be due to tendon laxness, peripheral neuropathy or loss of central control of gait due to age. Accelerometry may be a much more sensitive technique to analyze abnormalities in gait than standard video or observational gait analysis. Results are given as mean (SD) unless otherwise stated. 相似文献
82.
Enciso-Moreno JA Pernas-Buitrón N Ortiz-Herrera M Coria-Jiménez R 《Archives of medical research》2004,35(1):12-17
BACKGROUND: Serratia marcescens has been increasingly identified as a cause of infection in the immunocompromised host and in high-mortality-rate nosocomial outbreaks. It is thus important to use identification methods that allow study of the dynamics and evolution of nosocomial S. marcescens strains. The aim of this study was to identify S. marcescens strains isolated from nosocomial outbreaks in two pediatric hospitals by random amplification polymorphic DNA polymerase chain reaction (RAPD-PCR). METHODS: RAPD-PCR was used to study five S. marcescens populations isolated from four different nosocomial outbreaks that occurred in two pediatric hospitals. This method was compared with the widely used biotyping system described by Grimont and Grimont. RESULTS: The combination of biotypification and RAPD-PCR allowed accurate identification of S. marcescens strains isolated in nosocomial outbreaks at pediatric hospitals; by RAPD-PCR, we were able to analyze clonal variations in S. marcescens populations. We established bacterial dissemination patterns in hospital environments according to hospital administration of medical services and compared changes in bacterial DNA amplification patterns in each hospital related with clonal variations by selective pressures. CONCLUSIONS: RAPD-PCR is a useful method to identify S. marcescens strains associated with nosocomial outbreaks. 相似文献
83.
84.
Cervical cancer screening beliefs among young Hispanic women 总被引:5,自引:0,他引:5
OBJECTIVES: This study examined beliefs, attitudes, and personal characteristics that correlated with self-reported cervical cancer screening history among Hispanic women aged 18 to 25 years old in El Paso, TX, a large metropolitan area on the U.S.-Mexico border. METHODS: Data were collected through a cross-sectional, face-to-face survey. The study questionnaire was based primarily on the Health Belief Model, and included scales that measured perceived susceptibility and seriousness of cervical cancer, and perceived benefits and barriers to Pap test screening. The study questionnaire also included measures of acculturation, Pap test history, pregnancy and sexual history, use of birth control, type of medical insurance, and educational attainment. RESULTS: Sixty-nine percent reported ever having had a Pap test and 56% reported having had a test in the past year. Eighty percent reported that they were sexually active, and of these, 63% reported using birth control. Respondents understood the seriousness of cervical cancer, their susceptibility to cervical cancer, and the benefits of Pap testing; however, only 61% agreed that most young women whom they know have Pap tests. Greater acculturation and the belief that most young unmarried women have Pap tests were positively associated with ever having screening. The perception that the test would be painful and not knowing where to go for the test were negatively associated with ever having a Pap test. CONCLUSIONS: This study found suboptimal rates of screening for cervical cancer in a sample of young Hispanic women residing along the U.S.-Mexico border. Although women may understand the seriousness of cervical cancer and the benefits of screening, perceptions about Pap tests may pose barriers to undergoing screening. Efforts to increase screening also may need to focus specifically on women who are least acculturated, as they also were least likely to have had prior Pap tests. 相似文献
85.
Spatial and temporal regularities commonly exist in natural visual scenes. The knowledge of the probability structure of these regularities is likely to be informative for an efficient visual system. Here we explored how manipulating the spatio-temporal prior probability of stimuli affects human orientation perception. Stimulus sequences comprised four collinear bars (predictors) which appeared successively towards the foveal region, followed by a target bar with the same or different orientation. Subjects' orientation perception of the foveal target was biased towards the orientation of the predictors when presented in a highly ordered and predictable sequence. The discrimination thresholds were significantly elevated in proportion to increasing prior probabilities of the predictors. Breaking this sequence, by randomising presentation order or presentation duration, decreased the thresholds. These psychophysical observations are consistent with a Bayesian model, suggesting that a predictable spatio-temporal stimulus structure and an increased probability of collinear trials are associated with the increasing prior expectation of collinear events. Our results suggest that statistical spatio-temporal stimulus regularities are effectively integrated by human visual cortex over a range of spatial and temporal positions, thereby systematically affecting perception. 相似文献
86.
87.
INTRODUCTION: Cholinesterase inhibitors have been shown to improve cognitive function and improve or maintain global function. OBJECTIVE: To estimate the long-term economic impact of treating patients with Alzheimer's disease with galantamine in seven healthcare systems: Australia, Canada, Finland, New Zealand, Sweden, the Netherlands and the UK. METHODS: The time until patients require full-time care (FTC), defined as the consistent requirement for a significant amount of care giving and supervision each day, and the associated costs were evaluated using the 'Assessment of Health Economics in Alzheimer's Disease (AHEAD)' model. Efficacy data were obtained from three clinical trials comparing galantamine with placebo and local cost and resource use data were determined for each country. Forecast costs reported in Euros (2001 value), were made for up to 10 years in each healthcare system. All costs were determined from a perspective somewhat broader than that of a comprehensive payer, including social services. Both benefits and costs were discounted at 3%. RESULTS: Galantamine (16 mg/day) is predicted to delay the need for FTC by 6.8%, thus the cumulative cost of care over 10 years is expected to be reduced, and this offsets much or all of the cost of galantamine. Approximately five patients need to be treated to avoid 1 year of FTC. In each healthcare system, FTC was estimated to account for 61-92% of the cost. Savings were estimated for most of the countries. For those countries with an expected expense, there were reasonable costs per FTC month avoided (euro553, discounted) and costs per quality-adjusted life year gained (euro25,000). CONCLUSION: In addition to the clinical benefits associated with galantamine treatment, the savings predicted from delaying FTC may offset the treatment costs. 相似文献
88.
De Cicco C Trifirò G Baio S Sierra ML Pizzamiglio M Cassano E Prisco G Gatti G Galimberti V Luini A Paganelli G 《Cancer biotherapy & radiopharmaceuticals》2004,19(5):621-626
The aim of this study was to assess the utility of 99mTc-sestamibi scintimammography (SM) in patients with suspected primary or recurrent breast cancer. Forty-four (44) breast lesions (17 with suspected recurrence of disease) in 40 patients were included into the study. In these patients, the results of conventional diagnostic methods were equivocal or inconclusive. Twenty-one (21) lesions were palpable and 23 lesions were not. Histological examinations performed during the follow-up revealed malignancy in 24 specimens. SM correctly identified 21 of them, as well as 12 true negatives. There were 8 false-positive studies; therefore, the sensitivity of SM was 87.5%, specificity was 60%, positive predictive value (PPV) was 72.4%, and the negative predictive value (NPV) was 80%. The sensitivity in palpable lesions was 100%; three (3) false negatives, 1 recurrence, and 2 cancers, all of them nonpalpable. In conclusion, SM is useful in equivocal palpable lesions for resolving diagnostic uncertainty after conventional examination, and can limit the number of surgical interventions for benign disease. However, its use in nonpalpable tumors is not recommended. 相似文献
89.
90.
Quintero M Rojas-Atencio A Ruiz A González M Herrera J Atencio F Delgado W Urdaneta K Pérez F 《Investigación clínica》2003,44(4):327-335
The cytogenetic study is an important prognostic factor in Multiple Myeloma (MM). The chromosomal analysis has demonstrated to be essential for the genetic advise in relation to the diagnosis, prognosis and might suggest precociously, the most appropriate treatment for the majority of hematological malignancies. The objective of this investigation was to identify the chromosomal abnormalities in samples of bone marrow (BM) from patients with diagnosis of MM. The chromosomal studies were carried out in BM cultures, following the technique described by Yunis. Without exception the analysis was carried out previous to any treatment with cytostatics. Twenty two samples of BM were received for chromosomal studies in the Unit of Medical Genetics of the University of the Zulia (UGM-LUZ). In 19 out of 22 samples (86%) appropriate material was obtained by cytogenetic analysis; 6 (32%) showed normal karyotype and 13 (68%) presented numeric and structural chromosomal abnormalities. Eight (62%) of the chromosomal anomalies detected were numerics, three cases (38%) with hyperdiploidy involving chromosomes 3, 5, 7, 15, 17, 18, 19 and four cases (50%) with hypodiploidy involving the chromosomes 8, 16, 17, 18, X and Y. Triploidy was found in one case (12%). Structural abnormalities were present in 4 cases (31%) such as deletions 5p11, 11p14, 14q32, 17p11 and 1 case (7%) presented structural and numeric anomalies. This study shows that the majority of patients with multiple myeloma have several chromosomal abnormalities with some differences from other reports. 相似文献