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91.
Background: A key feature of health professionals’ training, irrespective of discipline, is the acquisition and application of clinical and communication skills. Despite this, little is known about the potential role of patient feedback on this process. This systematic review aimed to answer the question: How does feedback from patients impact upon healthcare student clinical skill development and learning?

Design: Systematic review of published literature.

Methods: Electronic databases were searched for studies that explored the effects of patient feedback on student learning and were published before March 2016. Eligible articles underwent methodological evaluation using the McMaster University Critical Evaluation Forms and data extraction.

Results: A total of 237 articles were retrieved following searches of electronic databases and hand searches of reference lists. Twelve (7 quantitative, 2 qualitative, 3 mixed methods) studies met the inclusion criteria. Eleven studies reported that patient feedback improved students’ clinical skills.

Conclusion: Minimal research has explored the impact of patient feedback on student learning. The research to date suggests that direct feedback from patients may be beneficial for the development of students’ communication and clinical skills; however, the wide variety of evaluation methods and the lack of validated tools for patients to provide feedback suggest that further exploration is warranted.  相似文献   
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Background and purpose — The optimal type and duration of antibiotic prophylaxis for primary arthroplasty of the hip and knee are subject to debate. We compared the risk of complete revision (obtained by a 1- or 2-stage procedure) for periprosthetic joint infection (PJI) after primary total hip or knee arthroplasty between patients receiving a single dose of prophylactic antibiotics and patients receiving multiple doses of antibiotics for prevention of PJI.Patients and methods — A cohort of 130,712 primary total hip and 111,467 knee arthroplasties performed between 2011 and 2015 in the Netherlands was analyzed. We linked data from the Dutch arthroplasty register to a survey collected across all Dutch institutions on hospital-level antibiotic prophylaxis policy. We used restricted cubic spline Poisson models adjusted for hospital clustering to compare the risk of revision for infection according to type and duration of antibiotic prophylaxis received.Results — For total hip arthroplasties, the rates of revision for infection were 31/10,000 person-years (95% CI 28–35), 39 (25–59), and 23 (15–34) in the groups that received multiple doses of cefazolin, multiple doses of cefuroxime, and a single dose of cefazolin, respectively. The rates for knee arthroplasties were 27/10,000 person-years (95% CI 24–31), 40 (24–62), and 24 (16–36). Similar risk of complete revision for infection among antibiotic prophylaxis regimens was found when adjusting for confounders.Interpretation — In a large observational cohort we found no apparent association between the type or duration of antibiotic prophylaxis and the risk of complete revision for infection. This does question whether there is any advantage to the use of prolonged antibiotic prophylaxis beyond a single dose.

Annually around 1 million patients receive a total hip or total knee prosthesis in the United States and over 190,000 hip and knee replacements are performed in England and Wales (Maradit et al. 2015, National Joint Registry for England and Wales 2018). The incidences of prosthetic replacement of the hip and knee are expected to increase (Kurtz et al. 2014). Prosthetic joint infection (PJI) following total hip or knee arthroplasty and the treatment thereof are catastrophic for patients and pose tremendous costs to healthcare systems (Poultsides et al. 2010, Zmistowski et al. 2013, Moore et al. 2015). Perioperative antibiotic prophylaxis remains an effective method of reducing the risk of PJI (Illingworth et al. 2013, Thornley et al. 2015). The type and duration of antibiotic prophylaxis are subject to debate.Both single-dose and multiple-dose antibiotic prophylaxis regimens have been advocated with comparable results (Thornley et al. 2015, Tan et al. 2019). The recommendations provided by the Second International Consensus Meeting of the MusculoSkeletal Infection Society (MSIS) and the European Bone and Joint Infection Society (EBJIS) advise that antibiotic prophylaxis should be administered 30–60 minutes before incision and discontinued within 24 hours after surgery (Hansen et al. 2014, Parvizi and Gehrke 2018). Large variation in prophylaxis regimens has been observed in the United Kingdom (Hickson et al. 2015). The Dutch national orthopedic association advises administration of antibiotic prophylaxis using a first- or second-generation cephalosporin starting 30–60 minutes preoperatively and discontinuing the antibiotic prophylaxis within 24 hours (Swierstra et al. 2009, Nederlandse Orthopaedische Vereniging 2018). The World Health Organization and, in the USA, the Centers for Disease Control and Prevention (CDC) recommend against the use of postoperative continuation of antibiotic prophylaxis and advocate for a single dose of antibiotics delivered preoperatively (Berrios-Torres et al. 2017). This recommendation is vehemently challenged by the American Association of Hip and Knee Surgeons and the International Consensus Meeting, which encourage their members to proceed with the current common practice of multiple-dose antibiotic prophylaxis protocols until more evidence is available (Yates 2018).We compared the risk of complete revision for infection in the 1st year following primary hip and knee arthroplasty according to the perioperatively administered antibiotic prophylaxis regimen by using data from the Dutch Arthroplasty Register (LROI).  相似文献   
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Background:

Recent studies demonstrate that the rapid antidepressant ketamine increases spine number and function in the medial prefrontal cortex (mPFC), and that these effects are dependent on activation of glutamate α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptors and brain-derived neurotrophic factor (BDNF). In vitro studies also show that activation of AMPA receptors stimulates BNDF release via activation of L-type voltage-dependent calcium channels (VDCC).

Methods:

Based on this evidence, we examined the role of BDNF release and the impact of L-type VDCCs on the behavioral actions of ketamine.

Results:

The results demonstrate that infusion of a neutralizing BDNF antibody into the mPFC blocks the behavioral effects of ketamine in the forced swim test (FST). In addition, we show that pretreatment with nifedipine or verapamil, two structurally-different L-type calcium channel antagonists, blocks the behavioral effects of ketamine in the FST. Finally, we show that ketamine treatment stimulates BDNF release in primary cortical neurons and that this effect is blocked by inhibition of AMPA receptors or L-type VDCCs.

Conclusions:

Taken together, these results indicate that the antidepressant effects of ketamine are mediated by activation of L-type VDCCs and the release of BDNF. They further elucidate the cellular mechanisms underlying this novel rapid-acting antidepressant.  相似文献   
99.

Background:

Major depressive disorder has been associated with abnormal resting-state functional connectivity (FC), especially in cognitive processing and emotional regulation networks. Although studies have found abnormal FC in regions of the default mode network (DMN), no study has investigated the FC of specific regions within the anterior DMN based on cytoarchitectonic subdivisions of the antero-medial pre-frontal cortex (PFC). Studies from different areas in the field have shown regions within the anterior DMN to be involved in emotional intelligence. Although abnormalities in this region have been observed in depression, the relationship between the ventromedial PFC (vmPFC) function and emotional intelligence has yet to be investigated in depressed individuals.

Methods:

Twenty-one medication-free, non–treatment resistant, depressed patients and 21 healthy controls underwent a resting state functional magnetic resonance imaging session. The participants also completed an ability-based measure of emotional intelligence: the Mayer-Salovey-Caruso Emotional Intelligence Test. FC maps of Brodmann areas (BA) 25, 10m, 10r, and 10p were created and compared between the two groups.

Results:

Mixed-effects analyses showed that the more anterior seeds encompassed larger areas of the DMN. Compared to healthy controls, depressed patients had significantly lower connectivity between BA10p and the right insula and between BA25 and the perigenual anterior cingulate cortex. Exploratory analyses showed an association between vmPFC connectivity and emotional intelligence.

Conclusions:

These results suggest that individuals with depression have reduced FC between antero-medial PFC regions and regions involved in emotional regulation compared to control subjects. Moreover, vmPFC functional connectivity appears linked to emotional intelligence.  相似文献   
100.
A liquid chromatography-high resolution mass spectrometry (LC-HRMS) method was developed using three peptide drugs: salmon calcitonin, bivalirudin, and exenatide as model systems to assess the suitability of this approach for monitoring peptide drug product quality. Calcitonin and its related impurities displayed linear responses over the range from 0.1 to 10 μM (R2 values for calcitonin salmon, Glu14-calcitonin, and acetyl-calcitonin were 0.995, 0.996, and 0.993, respectively). Intra-assay precision in terms of relative standard deviation (%RSD) was less than 10% at all tested concentrations. The accuracy of the method was greater than 85% as measured by spiking 0.1, 0.3, and 1% of Glu14-calcitonin and acetyl-calcitonin into a stock calcitonin solution. Limits of detection for calcitonin, Glu14-calcitonin, and acetyl-calcitonin were 0.02, 0.03, and 0.04 μM, respectively, indicating that an impurity present at less than 0.1% (0.1 μM) of the drug product API concentration (107 μM) could be detected. Method validation studies analyzing bivalirudin and exenatide drug products exhibited similar results to calcitonin salmon in regard to high selectivity, sensitivity, precision, and linearity. Added benefits of using LC-HRMS-based methods are the ability to also determine amino acid composition, confirm peptide sequence, and quantify impurities, even when they are co-eluting, within a single experiment. LC-HRMS represents a promising approach for the quality control of peptides including the measurement of any peptide-related impurities. While the development work performed here is focus on peptide drug products, the principles could be adapted to peptide drug substance.KEY WORDS: High resolution mass spectrometry, impurity profiling, LC-HRMS, peptide drug  相似文献   
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