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71.
Christopher C. Stewart Rex A. Wright Siu-Kuen Azor Hui and Angel Simmons 《Psychophysiology》2009,46(6):1141-1149
Female undergraduates performed an easy (fatigue low) or difficult (fatigue high) scanning task and then were presented mental arithmetic problems with instructions that they would earn a high or low chance of winning a prize if they did as well as or better than 50% of those who had performed previously. As expected, blood pressure responses in the second work period rose or tended to rise with fatigue where the chance of winning was high. By contrast, the responses tended weakly to decline with fatigue where the chance of winning was low. The pressure findings support the suggestion of a recent fatigue analysis that success importance should moderate fatigue influence on CV responses to a challenge so long as fatigued performers view success as possible. They also conceptually replicate previous fatigue results and provide a special class of evidence that fatigue influence on CV response is mediated by effort. 相似文献
72.
73.
Mustafa Balkaya Jan M Kr?ber Andre Rex Matthias Endres 《Journal of cerebral blood flow and metabolism》2013,33(3):330-338
Experimental treatment strategies and neuroprotective drugs that showed therapeutic promise in animal models of stroke have failed to produce beneficial effects in human stroke patients. The difficulty in translating preclinical findings to humans represents a major challenge in cerebrovascular research. The reasons behind this translational road block might be explained by a number of factors, including poor quality control in various stages of the research process, the validity of experimental stroke models, and differences in drug administration and pharmacokinetics. Another major difference between animal studies and clinical trials is the choice of end point or outcome measures. Here, we discuss the necessity of poststroke behavioral testing to bridge the gap between clinical and experimental end points. We review established sensory-motor tests for outcome determination after focal ischemia based on the published literature as well as our own personal experience. Selected tests are described in more detail and good laboratory practice standards for behavioral testing are discussed. This review is intended for stroke researchers planning to use behavioral testing in mice. 相似文献
74.
75.
Betsy Sleath Rex Ballinger David Covert Alan L. Robin John E. Byrd Gail Tudor 《The American journal of geriatric pharmacotherapy》2009,7(2):67-73
Objective: The purpose of the current study was to determine the self-reported prevalence of and factors associated with nonadherence with glaucoma medications in veteran outpatients.Methods: This survey study was conducted at a Veterans Affairs (VA) clinic. A survey was administered to patients with glaucoma. We calculated the percentage of self-reported adherence with glaucoma medications in each patient. Logistic regression was used to assess whether patient characteristics and difficulties with using glaucoma medications were related to patients' reporting that they were <100% adherent with their glaucoma medications in the previous week.Results: The survey was completed by 141 patients (men, 91.5%; mean [SD] age, 70.22 [11.60] years [range, 37–93 years]; black race, 45.4%; white race, 44.0%; “other” or data unavailable, 10.6%). Nonwhite patients were significantly less adherent in the previous week than were white patients (27.0% vs 11.3%; P < 0.05). A total of 67.4% patients reported ≥1 difficulty in using their glaucoma medications. The 3 most commonly reported difficulties were “drops fall on cheek” (29.1%), “too many drops come out” (20.6%), and “hard to read print” (17.0%). A total of 19.1% of patients self-reported using <100% of their glaucoma medications in the previous week. The number of difficulties reported was significantly associated with reporting being <100% adherent in the previous week (P<0.05).Conclusion: In this small sample of VA patients with glaucoma, adherence to glaucoma medications could be improved, especially among those who reported difficulties using their medications and those who were nonwhite. 相似文献
76.
Rex DK 《Gastrointestinal endoscopy》2000,51(1):33-36
BACKGROUND: Clinical studies have documented differences in detection rates of colorectal cancers and adenomas between experienced colonoscopists, the basis of which is unknown. The aim of this study was to determine whether colonoscopic withdrawal technique varies between 2 colonoscopists with known differences in adenoma detection rates. METHODS: Ten consecutive colonoscopic withdrawals by each of the 2 colonoscopists were videotaped and then assessed according to specific criteria by 4 experts blinded to who had performed the colonoscopies. RESULTS: Each of the 4 experts scored the colonoscopist with the lower miss rate significantly higher (p < 0.001) for each of 4 quality criteria: (1) examining the proximal sides of flexures, folds and valves, (2) cleaning and suctioning, (3) adequacy of distention, and (4) adequacy of time spent viewing. CONCLUSION: Higher quality colonoscopic withdrawal technique as determined by expert observers was associated with a colonoscopist with a previously documented lower miss rate for adenomas. Colonoscopic withdrawal technique should be subjected to further study and standards for withdrawal technique should be developed. 相似文献
77.
Rex Forehand Bryan Neighbors Michelle Wierson 《Journal of child psychology and psychiatry, and allied disciplines》1991,32(6):929-937
The differential change of boys and girls across pre-adolescence, early adolescence, and middle adolescence was examined. The participants were 259 children, their mothers, and their social studies teachers. The children completed a measure of internalizing problems and adults completed measures of the child's externalizing and internalizing problems and competence. Relative to girls, boys had more problems and less competence at pre-adolescence and/or less problems and more competence by mid-adolescence. A stressor, parental divorce, did not exacerbate the gender by developmental age period interaction. The differential vulnerability of boys and girls at different developmental periods is considered. 相似文献
78.
Hannah R. Krigman Rex C. Bentley Donald K. Strickland Cindy R. Miller Louis P. Dehner Kay Washington 《Pediatric blood & cancer》1995,25(1):52-59
Renal cell carcinoma is unusual in children. We report a case of anaplastic renal cell carcinoma arising in a 7-year-old girl following treatment for Stage III neuroblastoma. The renal cell carcinoma has unusual histologic and ultrastructural features, which are discussed. The case is further unusual in that few children with advanced stage neuroblastoma survive long enough to develop second malignant neoplasms. © 1995 Wiley-Liss, Inc. 相似文献
79.
Cyanosis, clubbing, and arterial oxygen desaturation may occur in patients with liver disease, and are attributed to the presence of pulmonary or peripheral arterio-venous shunting. Cardiac catheterisation and angiocardiography in a patient with a normal heart did not demonstrate the presence of abnormal arterio-venous anastomoses. Pulmonary shunting was proved when intravenous technetium-labelled macroaggregated albumin, normally held up in capillary networks, was passed quickly through the lungs and immediately detected in high systemic blood flow organs. The opening of peripheral and pulmonary anastomoses in patients with liver disease may be owing to the presence of a vasodilatory substance such as ferritin, which was found to be abnormally increased in the patient's blood. 相似文献
80.
Drugs intended to increase wellness or quality of life ("lifestyle drugs") have gained popularity and/or importance over recent years. Biogenic substances like nicotinamide adenine dinucleotide (NADH) are supposed to increase the physical and intellectual performance without side-effects. NADH is an energy-delivering co-substrate in the respiratory chain. Clinical studies showed positive effects of peripherally given NADH in Morbus Parkinson and major depression. NADH can be measured by its fluorescence. In this study a pulsed N2-laser combined with a fibre-optic probe and photomultipliers was used to induce and measure NADH fluorescence in the rat cortex. The aims of the study were to assess the suitability of the laser-induced spectroscopy for in vivo and on-line measurement of NADH in neuroscience and the assessment of the central availability of NADH after peripheral administration. NADH (50 mg/kg) but not the precursor nicotinamide caused a significant rise of the NADH fluorescence intensity indicating an increase of the NADH concentration in the rat cortex. In conclusion, the results suggest that NADH given orally or intraperitoneally increases the amounts of NADH in the brain. The results may thus help to explain the clinical effects reported. 相似文献