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目的 探讨自主学习结合情景模拟教学法在医学生技能培训中的应用效果和意义。方法 选取2012级的60 名医学生进行研究,随机分为试验组和对照组,每组各30 人,培训前对两组学员进行考核,成绩无统计学差异。对照组采用LBL+ 床旁带教的教学方法,试验组采用自主学习结合情景模拟教学方法进行技能培训。两组学生均培训2 个月后进行考核,对考试成绩进行分析比较。考核结束后进行问卷调查,对培训满意度进行调研。结果 试验组的技能考核成绩明显高于对照组,具有统计学意义(P < 0.05);试验组的理论成绩高于对照组,但不具有统计学意义(P > 0.05);试验组对培训的满意度(90%)明显高于对照组(77.8%),具有统计学意义(P < 0.05)。结论 采用自主学习结合情景模拟教学方法对医学生进行培训能明显提高临床技能培训效果,提高医学生培训满意度,是一种较好的实践技能教学方法。  相似文献   
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Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since it was first recognized in December 2019, it has resulted in the ongoing worldwide pandemic. Although acute hypoxic respiratory failure (AHRF) and acute respiratory distress syndrome (ARDS) are the main features of the disease, the involvement of other organs needs to be explored. There has been a growing concern regarding the association between acute kidney injury (AKI) and poor outcomes in SARS-CoV-2 patients. Based on current observational data, AKI is the 2nd most common cause of morbidity and mortality behind ARDS in SARS-CoV-2 patients. Angiotensin-converting enzyme 2 (ACE2) receptor has been shown to be the cornerstone of SARS-CoV-2 infection and possibly plays a significant role in the occurrence of renal injury. The pathogenesis of AKI is likely multifactorial that involves not only direct viral invasion but also dysregulated immune response in the form of cytokine storm, ischemia to kidneys, hypercoagulable state, and rhabdomyolysis, among others. We performed a literature search of the Pubmed and Google Scholar database from 1996 to 2020 using the following keywords: severe acute respiratory syndrome coronavirus 2, coronavirus disease 2019, angiotensin-converting enzyme 2 receptor, and acute kidney injury to find the most pertinent and highest-quality of evidence. Any cited references were reviewed to identify relevant literature. The purpose of this review is to discuss, explore, and summarize the relationship between AKI in SARS-CoV-2 patients, with a focus on its epidemiology, association with ACE2 receptors, and pathophysiology of AKI.  相似文献   
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Volunteer infection studies using the induced blood stage malaria (IBSM) model have been shown to facilitate antimalarial drug development. Such studies have traditionally been undertaken in single‐dose cohorts, as many as necessary to obtain the dose‐response relationship. To enhance ethical and logistic aspects of such studies, and to reduce the number of cohorts needed to establish the dose‐response relationship, we undertook a retrospective in silico analysis of previously accrued data to improve study design. A pharmacokinetic (PK)/pharmacodynamic (PD) model was developed from initial fictive‐cohort data for OZ439 (mixing the data of the three single‐dose cohorts as: n = 2 on 100 mg, 2 on 200 mg, and 4 on 500 mg). A three‐compartment model described OZ439 PKs. Net growth of parasites was modeled using a Gompertz function and drug‐induced parasite death using a Hill function. Parameter estimates for the PK and PD models were comparable for the multidose single‐cohort vs. the pooled analysis of all cohorts. Simulations based on the multidose single‐cohort design described the complete data from the original IBSM study. The novel design allows for the ascertainment of the PK/PD relationship early in the study, providing a basis for rational dose selection for subsequent cohorts and studies.

Study Highlights
  • WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?
☑ Volunteer infection studies are routinely used in antimalarial drug development to generate early pharmacokinetic/pharmacodynamic data for compounds.
  • WHAT QUESTION DID THIS STUDY ADDRESS?
☑ Can in silico analyses be used to suggest improvements to volunteer infection study designs?
  • WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?
☑ Multiple dose adaptive trial designs can potentially reduce the number of cohorts needed to establish the dose‐response relationship in volunteer infection studies.
  • HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?
☑ Real time data analyses can be used to recommend doses for adaptive volunteer infection studies.

Volunteer infection studies using the induced blood stage malaria (IBSM) model have been recognized as a valuable system for defining the key pharmacokinetic (PK) and pharmacodynamic (PD) relationships for dose selection in antimalarial drug development. 1 , 2 , 3 , 4 , 5 , 6 , 7 In such studies, healthy volunteers are inoculated intravenously with a given quantity (with small variability) of Plasmodium‐infected red cells. Parasitemia is then followed by quantitative polymerase chain reaction until a prespecified treatment threshold is reached when the test drug is administered. Parasite and drug concentrations are then measured. These studies are conducted prior to phase II dose‐response (D‐R) trials and can be included in an integrated first‐in‐human study protocol, or after completion of the first‐in‐human PK and safety study. IBSM studies have been typically designed as flexible multiple cohort studies where each volunteer of one cohort receives a single dose of the same amount of drug (“single dose per cohort”). 2 , 3 , 4 , 5 After each cohort, a decision is made to stop or to add a cohort to test a lower or higher dose based on the response observed in the previous cohorts.For the multiple single‐dose‐per‐cohort design, the starting dose is typically selected based on safety and PK information from a phase I single ascending dose (SAD) study and, more recently, on preclinical data from a severe combined immunodeficient mouse model, with the dose selected on the basis of being best able to inform the D‐R relationship, rather than aiming for cure. This approach, where a single dose is tested in all subjects of the initial cohort, risks missing the dose likely to be most informative for defining the PK/PD relationship.An alternative approach is to spread a range of doses across a smaller number of subjects within the initial cohort and use PK/PD models developed based on data from this cohort to support dose selections of subsequent cohorts and studies. Using data from a previous study, 2 we undertook an in silico investigation of such an adaptive study design, aiming to reduce the number of subjects exposed to inefficacious doses, and to establish a D‐R relationship. This multiple‐dose‐groups‐per‐cohort design, referred to as the “2‐2‐4” design, is contrasted with the already implemented study design depicted in Figure  1 .Open in a separate windowFigure 1Comparison of standard and adaptive designs of IBSM studies. A/B/C, dose levels to be selected during the progress of the study based on pharmacokinetic/pharmacodynamic results of the initial cohort; CHMI, controlled human malaria infection; D‐R, dose‐response; IBSM, induced blood stage malaria infection; n, number of subjects at each dose.The objectives of this retrospective analysis were to: (i) compare PK/PD parameter estimates from the initial cohort of the 2‐2‐4 study design with the prior results from the data of the full study and (ii) propose a preliminary workflow to establish D‐R early in an IBSM study, and use modeling and simulation (M&S) to support dose selections for subsequent cohorts and later phase clinical trials.  相似文献   
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Our knowledge of the radiological spectrum of myelin oligodendrocyte glycoprotein antibody associated disease (MOGAD) is growing rapidly. An update on the radiological features of the disease, and its evolution is thus necessary. Magnetic resonance imaging (MRI) has an increasingly important role in the differential diagnosis of MOGAD particularly from aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (AQP4-NMOSD), and multiple sclerosis (MS). Differentiating these conditions is of prime importance because the management is different between the three inflammatory diseases, and thus could prevent further attack-related disability. Therefore, identifying the MRI features suggestive of MOGAD has diagnostic and prognostic implications. We herein review optic nerve, spinal cord and the brain MRI findings from MOGAD adult patients, and compare them to AQP4-NMOSD and MS.  相似文献   
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ObjectiveThis open-label, controlled, randomized study assessed the safety, tolerability, and efficacy of StrataGraft tissue compared to autograft in the treatment of deep partial-thickness (DPT) burns.MethodsThirty subjects with DPT thermal burns (3%–43% total body surface area) were treated with StrataGraft tissue as follows: cohort 1, ≤220 cm2 refrigerated tissue; cohort 2, ≤440 cm2 refrigerated tissue; and cohort 3, ≤440 cm2 cryopreserved tissue. On each subject, two comparable areas of DPT burn were randomized to receive StrataGraft tissue or autograft. Coprimary end points were the percent area of the StrataGraft tissue treatment site undergoing salvage autografting by Day 28 and wound closure of treatment sites by 3 months.ResultsBy Day 28, no StrataGraft tissue treatment sites underwent autografting. By 3 months, 93% and 100% of the StrataGraft tissue and autograft treatment sites achieved complete wound closure, respectively. No significant differences in observer total and overall opinion POSAS scores between StrataGraft tissue and autograft treatment sites were observed at any timepoint. The most common adverse event was pruritus (17%).ConclusionsStrataGraft tissue treatment of DPT thermal burns reduced the need for autograft, resulted in wound closure and treatment-site cosmesis comparable to that of autograft, and was well tolerated.  相似文献   
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