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991.
Modern medical simulation technology (MST) debuted in 1960 with the development of Resusci Annie (Laerdal 2007), which assisted students in the acquisition of proper ventilation and compression techniques used during basic life support. Following a steady stream of subsequent technological advances and innovations, MST manufacturers are now able to offer training aids capable of facilitating innovative learning in such diverse areas as human patient simulators, simulated clinical environments, virtual procedure stations, virtual medical environments, electronic tutors, and performance recording. The authors list a number of the most popular MSTs presently available while citing evaluative efforts undertaken to date regarding the efficacy of MST to the medical profession. They conclude by proposing a variety of simulation innovations of prospective interest to both medical and technology personnel while offering healthcare administrators a series of recommended considerations when planning to integrate MST into existing medical systems.  相似文献   
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The purpose of this study was to determine and compare the effect of various concentrations and grades of Carbopol on trypsin-induced degradation of a prototype substrate, Nα-benzoyl-L-arginine ethyl ester hydrochloride (BAEE). Effect of other reaction variables, such as viscosity and ionic strength of the medium on the trypsin activity, was also analyzed simultaneously. Four concentrations and three commercially available grades of Carbopol were used. The effect of Carbopol was expressed in terms of change in the velocity of degradation reaction. A modified trypsin assay was developed and used for analysis. Up to a concentration of 0.35% w/v, Carbopol® 934P showed a concentration-dependent increase in its ability to reduce the rate of enzymatic hydrolysis of BAEE. Similar inhibitory effect was observed with all three grades of Carbopol. The activity of trypsin was unaffected by other reaction variables, suggesting that interaction between the protein and the polymer could be the mechanism responsible for reduced trypsin activity. This study suggests that Carbopol can be a useful excipient for oral delivery of bioactive proteins and peptides, due to its ability to reduce the enzyme-induced degradation of these agents.  相似文献   
995.
996.
When investigating cancer etiology, epidemiologists often correlate estimates of current dietary practices to cancer incidence. There is evidence that diets may be basically stable over time due to deep‐rooted habits; however, changes in eating behavior are often associated with life‐style or health‐status changes. By using a diet‐related life‐event schedule, dietary changes resulting from life events may be more easily recalled and a more accurate characterization of diet patterns during neoplasm initiation may be made.  相似文献   
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Mitochondria play a critical role in the cardiomyocyte physiology by generating majority of the ATP required for the contraction/relaxation through oxidative phosphorylation (OXPHOS). Aging is a major risk factor for cardiovascular diseases (CVD) and mitochondrial dysfunction has been proposed as potential cause of aging. Recent technological innovations in Seahorse XFe24 Analyzer enhanced the detection sensitivity of oxygen consumption rate and proton flux to advance our ability study mitochondrial function. Studies of the respiratory function tests in the isolated mitochondria have the advantages to detect specific defects in the mitochondrial protein function and evaluate the direct mitochondrial effects of therapeutic/pharmacological agents. Here, we provide the protocols for studying the respiratory function of isolated murine cardiac mitochondria by measuring oxygen consumption rate using Seahorse XFe24 Analyzer. In addition, we provide details about experimental design, measurement of various respiratory parameters along with interpretation and analysis of data.  相似文献   
1000.
As the HIV+ population ages, the risk for and need to screen for HIV-associated neurocognitive disorders (HAND) increases. The aim of this study is to determine the utility and ecological validity of the Montreal Cognitive Assessment (MoCA) among older HIV+ adults. A total of 100 HIV+ older adults aged 50 years or over completed a comprehensive neuromedical and neurocognitive battery, including the MoCA and several everyday functioning measures. The receiver operating characteristic curve indicates ≤26 as the optimal cut-off balancing sensitivity (84.2%) and specificity (55.8%) compared to “gold standard” impairment as measured on a comprehensive neuropsychological battery. Higher MoCA total scores are significantly (p < .01) associated with better performance in all individual cognitive domains except motor abilities, with the strongest association with executive functions (r = ?0.49, p < .01). Higher MoCA total scores are also significantly (p <.01) associated with fewer instrumental activities of daily living declines (r = ?0.28), fewer everyday cognitive symptoms (r = ?0.25), and better clinician-rated functional status (i.e., Karnofsky scores; r = 0.28); these associations remain when controlling for depressive symptoms. HIV+ individuals who are neurocognitively normal demonstrate medium-to-large effect size differences in their MoCA performance compared to those with asymptomatic neurocognitive impairment (d = 0.85) or syndromic HAND (mild neurocognitive disorder or HIV-associated dementia; d = 0.78), while the latter two categories do not differ. Although limited by less than optimal specificity, the MoCA demonstrates good sensitivity and ecological validity, which lends support to its psychometric integrity as a brief cognitive screening tool among older HIV+ adults.  相似文献   
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