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排序方式: 共有1581条查询结果,搜索用时 61 毫秒
1.
Timothy C. Evans MD PhD ; Keren H. Wick PhD ; Douglas M. Brock PhD ; Douglas C. Schaad PhD ; Ruth Ballweg MPA PA-C 《The Journal of rural health》2006,22(3):212-219
CONTEXT: The physician assistant profession has been moving toward requiring master's degrees for new practitioners, but some argue this could change the face of the discipline. PURPOSE: To see if there is an association between physician assistants' academic degrees and practice in primary care, in rural areas, and with the medically underserved. METHODS: Surveys were sent to 880 graduates of the first 32 University of Washington physician assistant classes through 2000. Respondents noted their academic degree at program entry and the highest degree attained at any time up to the time of survey. Relationships between practice characteristics and academic degree levels were tested by unadjusted odds ratios and logistic regression after controlling for year of graduation and sex. RESULTS: Of the 478 respondents, 54% worked in primary care, about 30% practiced in nonmetropolitan communities, and 42% reported providing care for the medically underserved. Respondents with no degree (33% of total at entry, 24% at survey) were significantly more likely than degree holders to work in primary care and nonmetropolitan areas. Respondents with no degree at program entry were significantly more likely, and those with no degree at the time of the survey were marginally more likely, to self-report work with the medically underserved. CONCLUSION: Respondents with no academic degree are significantly more likely to demonstrate a commitment to primary, rural, and underserved health care. These findings may inform the national debate about the impact of required advanced degrees on the practice patterns of nonphysician providers. 相似文献
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Jin H. Han MD MSc Karen F. Miller RN MPA Alan B. Storrow MD 《Academic emergency medicine》2007,14(3):228-233
Background: Elder patients with acute coronary syndromes (ACS) are less likely to receive cardiac catheterization. The reasons for this are unclear.
Objectives: To assess whether elder patients who had a documented history of dementia, lived in extended care facilities, or had do not intubate–do not resuscitate (DNR-DNI) advance directives were less likely to receive cardiac catheterization, despite having ACS with high-risk features.
Methods: This was a medical record review conducted at an urban teaching hospital. DNR-DNI status before hospitalization, extended care facility (nursing home or assisted living) residence, and a previous diagnosis of dementia were obtained from the medical record. Patients 65 years and older who presented to the emergency department with acute myocardial infarction or with unstable angina with ST segment deviation were included. Univariate and multivariate logistic regression were performed, and odds ratios (ORs) were reported with their 95% confidence intervals (CIs).
Results: Of the 201 eligible patients, 66 (32.8%) patients did not undergo cardiac catheterization. In the univariate analysis, patients who had dementia, resided in extended care facilities, or were DNR-DNI were less likely to receive cardiac catheterization. Only extended care facility residence (OR, 0.18; 95% CI = 0.04 to 0.83) and DNR-DNI status (OR, 0.19; 95% CI = 0.04 to 0.92) remained significantly associated with decreased cardiac catheterization in the multivariate analysis.
Conclusions: Elder patients with ACS residing in extended care facilities or who are DNR-DNI are less likely to receive cardiac catheterization. Future studies concerning the quality of ACS care for elders should take these variables into account. 相似文献
Objectives: To assess whether elder patients who had a documented history of dementia, lived in extended care facilities, or had do not intubate–do not resuscitate (DNR-DNI) advance directives were less likely to receive cardiac catheterization, despite having ACS with high-risk features.
Methods: This was a medical record review conducted at an urban teaching hospital. DNR-DNI status before hospitalization, extended care facility (nursing home or assisted living) residence, and a previous diagnosis of dementia were obtained from the medical record. Patients 65 years and older who presented to the emergency department with acute myocardial infarction or with unstable angina with ST segment deviation were included. Univariate and multivariate logistic regression were performed, and odds ratios (ORs) were reported with their 95% confidence intervals (CIs).
Results: Of the 201 eligible patients, 66 (32.8%) patients did not undergo cardiac catheterization. In the univariate analysis, patients who had dementia, resided in extended care facilities, or were DNR-DNI were less likely to receive cardiac catheterization. Only extended care facility residence (OR, 0.18; 95% CI = 0.04 to 0.83) and DNR-DNI status (OR, 0.19; 95% CI = 0.04 to 0.92) remained significantly associated with decreased cardiac catheterization in the multivariate analysis.
Conclusions: Elder patients with ACS residing in extended care facilities or who are DNR-DNI are less likely to receive cardiac catheterization. Future studies concerning the quality of ACS care for elders should take these variables into account. 相似文献
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Robert A. Hirst Hasan Yesilkaya Edwin Clitheroe Andrew Rutman Nichola Dufty Timothy J. Mitchell Christopher OCallaghan Peter W. Andrew 《Infection and immunity》2002,70(2):1017-1022
The Streptococcus pneumoniae pore-forming toxin, pneumolysin, is an important virulence factor in pneumococcal pneumonia. The effect of pneumolysin on human lung epithelial and monocyte cell viability was compared. Pneumolysin caused a dose-dependent loss of viability of human lung epithelial (A549 and L132) and monocyte (U937 and THP-1) cell lines. Analysis of the dose-response curves revealed similar log 50% inhibitory concentration (pIC(50)) values for A549, L132, and THP-1 of 0.12+/- 0.1, 0.02+/- 0.04, and 0.12+/- 0.13 hemolytic units (HU), respectively, but U937 cells showed a significantly greater pIC(50) of 0.42+/- 0.12 HU. Differentiation of A549 and L132 with phorbol ester or THP-1 with gamma interferon had no effect on their sensitivity to pneumolysin. However, a significant decrease in the potency of pneumolysin against U937 cells followed gamma interferon treatment. The Hill slopes of the inhibition curves were greater than unity, indicating that pneumolysin may act with positive cooperativity. Analysis of pneumolysin-treated THP-1 cells by electron microscopy revealed membrane lesions of between 100 and 200 nm in diameter. 相似文献
7.
OBJECTIVE: We examined sleep, daytime sleepiness and the ability to stay awake during the day in patients affected with retinitis pigmentosa (RP), to further delineate the role of photoreceptors in the circadian cycle. METHODS: Twelve individuals diagnosed with RP (40 +/- 8 years) And 12 normally sighted healthy individuals (39 +/- 7 years) matched for age, body mass index (BMI) and sex were selected for the study. Participants had their sleep recorded on two consecutive nights and were monitored on the two following days. On the first day, their ability to stay awake and on the second, their sleep propensity were assessed using the Maintenance of Wakefulness Test (MWT) and the Multiple Sleep Latency Test (MSLT), respectively. Self-report measures were obtained using the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS), and the Toronto Hospital Alertness Test (THAT). RESULTS: Subjective daytime sleepiness (ESS: 9 +/- 5 vs. 6 +/- 4, P=0.053) and objectively measured sleep propensity (MSLT: 10 +/- 5 vs. 17 +/- 3 min, P < 0.000) were significantly higher in RP patients than controls, whilst their alertness (THAT: 29 +/- 9 vs. 38 +/- 7, P=0.016) and ability to stay awake (MWT: 21 +/- 9 vs. 29 +/- 2 min, P=0.006) were significantly reduced. Retinitis pigmentosa participants had more disturbed nighttime sleep, with significantly more awakenings (arousal index: 14 +/- 8 vs. 8 +/- 6 h, P=0.039), and tended to have less rapid eye movement (REM) sleep (19 +/- 5 vs. 22 +/- 3%, P=0.094). CONCLUSION: Patients with RP have increased daytime sleepiness, reduced alertness and more disturbed nighttime sleep of poorer quality than their normally sighted counterparts, suggesting an influence of photoreceptor degeneration on the circadian cycle. 相似文献
8.
Rorden C Driver J 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2001,137(3-4):487-496
Research on visual attention has demonstrated that covert attention can be focused on particular locations within one hemifield,
but that a specific "meridian" cost may also be found for shifting attention between hemifields. These issues have received
less consideration for audition, even though reliable behavioral measures for the effects of spatial attention on hearing
are now available. We examined the spatial distribution of covert attention in an auditory task following spatially non-predictive
peripheral auditory cues (which should induce exogenous attention shifts), or following symbolic central cues that predicted
the likely location for the auditory target (to induce endogenous attention shifts). In both cases, we found that attention
can be focused not only on one hemifield versus another, but also within one hemifield in an auditory task. However, there
was no unequivocal evidence for a meridian effect in audition.
Electronic Publication 相似文献
9.
Schindler I Rice NJ McIntosh RD Rossetti Y Vighetto A Milner AD 《Nature neuroscience》2004,7(7):779-784
When we reach out to pick something up, our arm is directed to the target by visuomotor networks in the cortical dorsal stream. However, our reach trajectories are influenced also by nontarget objects, which might be construed as potential obstacles. We tested two patients with bilateral dorsal-stream (parietal lesions, both of whom were impaired at pointing to visual stimuli (optic ataxia). We asked them to reach between two cylinders, which varied in location from trial to trial. We found that the patients' reaches remained invariant with changes in obstacle location. In a control task when they were asked to point midway between the two objects, however, their responses shifted in an orderly fashion. We conclude that the dorsal stream provides the visual guidance we automatically build into our movements to avoid potential obstacles, as well as that required to ensure arrival at the target. 相似文献
10.
Functional imaging studies of priming-related repetition phenomena have become widely used to study neural object representation. Although blood oxygenation level-dependent (BOLD) repetition decreases can sometimes be observed without awareness of repetition, any role for spatial attention in BOLD repetition effects remains largely unknown. We used fMRI in 13 healthy subjects to test whether BOLD repetition decreases for repeated objects in ventral visual cortices depend on allocation of spatial attention to the prime. Subjects performed a size-judgment task on a probe object that had been attended or ignored in a preceding prime display of 2 lateralized objects. Reaction times showed faster responses when the probe was the same object as the attended prime, independent of the view tested (identical vs. mirror image). No behavioral effect was evident from unattended primes. BOLD repetition decreases for attended primes were found in lateral occipital and fusiform regions bilaterally, which generalized across identical and mirror-image repeats. No repetition decreases were observed for ignored primes. Our results suggest a critical role for attention in achieving visual representations of objects that lead to both BOLD signal decreases and behavioral priming on repeated presentation. 相似文献