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1.
Phenomenon: Academic health centers face significant challenges trying to improve medical education while meeting patient care needs. In response to problems with traditional forms of didactic education, many residency programs have transitioned to Academic Half Day (AHD), a curricular model in which learning is condensed into half-day blocks. In this model, trainees have protected educational time free from clinical responsibilities. However, an understanding of the impact on attending physicians and patient care when residents depart clinical sites for learning activities has not been well described. We sought to explore attending physicians’ perspectives when residents depart clinical sites to attend AHD. Approach: We performed a qualitative study with a grounded theory approach using individual semistructured interviews (December 2016–April 2017) of attending physicians who worked at inpatient and emergency department clinical sites from which residents departed to attend AHD. We used the constant comparative method, generating codes using an iterative approach and continuing sampling until saturation was reached. Major themes were identified and disagreements were resolved by consensus. Findings: Fifteen attending physicians from 6 clinical services were interviewed. Data analysis yielded 5 themes: emotional strain of workload, technology and systems challenges, patient safety and care concerns, disrupted resident learning, and the challenge to optimize resident education. Attending physicians, already working on busy services, felt frustrated and perceived having an increased workload when residents departed for AHD. They were concerned about safely entering orders in the electronic health record, impeded patient workflow, and further disruption of resident schedules already disrupted by duty hour restrictions and continuity clinic. Attending physicians described the importance of experiential learning from caring for patients and from structured didactic learning; however, the optimal balance was uncertain. Insights: We found that attending physicians experienced significant emotional strain, faced technological challenges, and were concerned about impeded workflow and patient safety when residents departed clinical sites for AHD. This is likely to be true whenever residents are pulled out of the clinical setting for any reason. Educators need to partner with hospital administrators to provide appropriate support for attending physicians when residents leave clinical sites, evaluate the effectiveness of different educational models, and determine how structured learning activities fit into the overall curriculum.  相似文献   
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The SV40 T antigen has been used to generate immortalized cells from rheumatoid arthritis (RA) synovial fibroblasts (RASFs) that are commonly used in lieu of primary RASFs. In the current study, we investigated the effect of stimulation by tissue necrosis factor alpha (TNF-α) and interleukin 17 (IL-17) on primary and immortalized RASFs in order to gauge the appropriateness of the use of immortalized RASFs, the MH7A cell line, in the study of RA pathogenesis. Changes in the levels of secretion and expression of 8 proteins associated with RA upon stimulation were assessed by multiplex immunoassay. IL-17 stimulation had a minimal impact on protein secretion and expression for primary and immortalized cells. Basic fibroblast growth factor (FGF-2) was not detectable for the primary cells but was detectable for the immortalized cells. In contrast, monocyte chemoattractant protein 1 (MCP-1) was detectable for primary cells but was undetectable for immortalized cells. In general, protein expression and secretion by cells stimulated with TNF-α were significantly increased. For primary cells, several proteins were below the limit of detection for unstimulated cells and cells stimulated with IL-17, while levels for TNF-α-stimulated cells were within the detectable range. For the same proteins, expression was observed for immortalized cells, regardless of stimulation, suggestive of constitutive activation of the NF-κB signaling pathway. The current study therefore provides strong evidence that immortalized and primary RASFs differ in regard to protein expression and secretion and therefore may not be appropriate for use in the study of RA pathogenesis.  相似文献   
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BACKGROUND: Heightened activity of the sympathetic nervous system in heart failure patients is a major contributor to disease progression and death. I-123 metaiodobenzylguanidine (MIBG) provides an accurate, noninvasive method to assess cardiac sympathetic nerve activity. METHODS: Thirty-seven patients with New York Heart Association class II, III, or IV heart failure underwent baseline measurement of I-123 MIBG heart-to-mediastinum ratios, maximum oxygen consumption, radionuclide left ventricular ejection fraction, and plasma norepinephrine levels. Patients were followed 48.8+/-8.6 months to endpoints of cardiac death or transplantation. The heart-to-mediastinum ratio of I-123 MIBG activity measured 15 minutes after injection was the only independent predictor of transplant-free survival (P<.0001). I-123 MIBG imaging at 15 minutes identified patients with subsequent cardiac transplantation or death with a sensitivity of 92% and specificity of 72%, whereas the corresponding values for maximum oxygen consumption were 75% and 56%. By Kaplan-Meier survival analysis, the time to a cardiac endpoint was significantly shorter in patients with a 15-minute I-123 MIBG heart-to-mediastinum ratio below the group mean ratio of 1.536, compared with patients with a preserved I-123 MIBG ratio. Maximum oxygen consumption was not predictive of time to cardiac transplant or death. CONCLUSIONS: In this study of patients with congestive heart failure resulting from dilated cardiomyopathy, a 15-minute heart-to-mediastinum ratio of I-123 MIBG activity provided more accurate prediction of cardiac transplantation or death than other standard clinical tests.  相似文献   
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Seeding cells into porous ceramic substrates has been shown to improve outcomes in surgical repair of large bone defects, but the physics underlying cellular ingress into such scaffolds remains elusive. This paper demonstrates capillary forces as a novel, yet simple, self-loading or self-seeding mechanism for rigid, microporous substrates. Capillary forces were found to draw cells through a microporous network with interconnections smaller than the diameter of the cells in suspension. Work here emphasizes CaP-based bone scaffolds containing both macroporosity (>100 μm) and microporosity (5–50 μm); these have been shown to improve bone formation in vivo as compared to their macroporous counterparts and also performed better than microporous scaffolds containing BMP-2 by some measures of bone regeneration. We hypothesize that capillary force driven self-seeding in both macro- and micropores may underlie this improvement, and present a mathematical model and experiments that support this hypothesis. The cell localization and penetration depth within these two-dimensional substrates in vitro depends upon both the cell type (size and stiffness) and the capillary forces generated by the microstructure. Additional experiments showing that cell penetration depth in vitro depends on cell size and stiffness suggest that microporosity could be tailored to optimize cell infiltration in a cell-specific way. Endogenous cells are also drawn into the microporous network in vivo. Results have important implications for design of scaffolds for the healing of large bone defects, and for controlled release of drugs in vivo.  相似文献   
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BackgroundThe Seattle Heart Failure Model (SHFM) is a multivariable model with proven prognostic value. Cardiopulmonary exercise testing (CPX) and neurohormonal markers (eg, B-type natriuretic peptide [BNP]) are also well accepted assessment techniques in the HF population and have both demonstrated robust prognostic value. The purpose of this investigation was to assess the combined prognostic value of the SHFM and CPX.Methods and ResultsThis study included all 453 patients enrolled in the Multicenter In-Sync Randomized Clinical Evaluation (MIRACLE) trial. Baseline SHFM and CPX were used. Both peak oxygen consumption (VO2) and ventilatory efficiency (VE/VCO2) were determined. In a univariate Cox proportional model analysis, SHFM and log-transformed peak VE/VCO2 were stronger predictors of 6-month mortality (both P < .001) than log-transformed BNP (P = .013) or peak VO2 (P = .066). In a multivariable Cox proportional hazards model, neither peak VO2 nor BNP were independent predictors when added to the SHFM (P > .1). Conversely, peak VE/VCO2 was a strong independent predictor when added to the SHFM, with an increase in the Cox proportional hazards model Wald χ2 from 22.7 for SHFM alone to 33.8 with inclusion of log-transformed peak VE/VCO2 (P < .0001) and significant changes in the net reclassification improvement and integrated discrimination index (both P < .002).ConclusionsThese results indicate that the SHFM and peak VE/VCO2 work synergistically to improve prognostic resolution. Further investigation is needed to continue to optimize multivariable prognostic models in patients with HF, a chronic disease population that continues to suffer from a high adverse event rate despite advances in medical care.  相似文献   
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The study was to determine the effect of preexisting pain on the perception of a painful stimulus. We conducted a cross-section study at an urban ED using convenience sampling. Adult patients who had a 20-g IV catheter placed as part of their ED care were eligible for the study. Patients were excluded for the following reasons: more than one IV attempt, altered mental status, visual impairment, intoxication, or a physical abnormality at the IV site. Patients were asked to indicate on a 10-cm visual analog scale (VAS) the amount of pain they had at baseline immediately before IV placement. They were then asked to indicate on a separate VAS the amount of pain caused by the IV placement. Correlation between baseline pain and pain of the IV was assessed using Pearson's rho. One hundred patients were enrolled in the study. The pain of IV placement did not differ significantly by gender, race, who placed the IV, or the location of the IV. The correlation between baseline pain and pain of the IV placement was poor (rho =.14, confidence interval:-.06-.33). The response to a standardized painful stimulus among ED patients does not correlate highly with the severity of preexisting pain.  相似文献   
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Background

Marijuana is currently the most commonly used drug on college campuses. Marijuana use among college students is increasing, and many students begin using marijuana during college. The goal of this study was to investigate predictors of lifetime marijuana use at college entry and initiation during freshman year.

Methods

We used responses from the first two semesters of a longitudinal study of 3146 students from 11 colleges in North Carolina and Virginia. Random-effects logistic regression models were constructed to identify factors that predict lifetime marijuana use at college entry and initiation during freshman year.

Results

Nearly 30% of students reported ever having used marijuana at college entry. Among students who had never used marijuana prior to college, 8.5% initiated use during freshman year. In multivariable logistic regression models, having at least $100 per month in spending money; attending church rarely or never; current use of cigarettes, alcohol, and hookah tobacco; lifetime use of other illicit drugs; and a higher propensity toward sensation seeking were associated with a higher likelihood of having used marijuana at least once at college entry. Hispanic ethnicity, living on campus, and current use of cigarettes and alcohol were associated with a higher likelihood of initiating marijuana use during freshman year.

Conclusion

These results have implications for targeting substance abuse prevention programs on college campuses.  相似文献   
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