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161.
Background: Disaster triage is an infrequent, high-stakes skill set used by emergency medical services (EMS) personnel. Screen-based simulation (SBS) provides easy access to asynchronous disaster triage education. However, it is unclear if the performance during a SBS correlates with immersive simulation performance. Methods: This was a nested cohort study within a randomized controlled trial (RCT). The RCT compared triage accuracy of paramedics and emergency medical technicians (EMTs) who completed an immersive simulation of a school shooting, interacted with an SBS for 13 weeks, and then completed the immersive simulation again. The participants were divided into two groups: those exposed vs. those not exposed to 60?Seconds to Survival© (60S), a disaster triage SBS. The aim of the study was to measure the correlation between SBS triage accuracy and immersive simulation triage accuracy. Improvements in triage accuracy were compared among participants in the nested study before and after interacting with 60S, and with improvements in triage accuracy in a previous study in which immersive simulations were used as an educational intervention. Results: Thirty-nine participants completed the SBS; 26 (67%) completed at least three game plays and were included in the evaluation of outcomes of interest. The mean number of plays was 8.5 (SD =7.4). Subjects correctly triaged 12.4% more patients in the immersive simulation at study completion (73.1% before, 85.8% after, P?=?0.004). There was no correlation between the amount of improvement in overall SBS triage accuracy, instances of overtriage (P?=?0.101), instances of undertriage (P?=?0.523), and improvement in the second immersive simulation. A comparison of the pooled data from a previous immersive simulation study with the nested cohort data showed similar improvement in triage accuracy (P?=?0.079). Conclusions: SBS education was associated with a significant increase in triage accuracy in an immersive simulation, although triage accuracy demonstrated in the SBS did not correlate with the performance in the immersive simulation. This improvement in accuracy was similar to the improvement seen when immersive simulation was used as the educational intervention in a previous study.  相似文献   
162.
Smythe  JS; Spring  FA; Gardner  B; Parsons  SF; Judson  PA; Anstee  DJ 《Blood》1995,85(10):2929-2936
This report describes the production and characterization of 13 rodent monoclonal antibodies to the human erythrocyte anion transport protein AE1 (syn. band 3). Eleven antibodies (4 murine and 7 rat) recognize epitopes dependent on the integrity of the third extracellular loop of the protein. Two antibodies (1 murine and 1 rat) recognize epitopes on the N-terminal cytoplasmic domain. Quantitative binding studies using radioiodinated IgG and Fab fragments of antibodies to extracellular epitopes on AE1 ranged from 77,000 to 313,000 (IgG) and from 241,000 to 772,000 (Fab) molecules bound at saturation. The results indicate that the epitopes recognized by different antibodies vary in their accessibility and suggest that there is heterogeneity in the organization of individual AE1 molecules in the red blood cell membrane. Quantitative binding studies on South East Asian ovalocytes using several antibodies to AE1 and an anti-Wrb show a marked reduction in the number of antibody molecules bound at saturation. These results are consistent with the existence of highly cooperative interactions between transmembrane domains of AE1 in normal erythrocytes and the disruption of these interactions in the variant AE1 found in South East Asian ovalocytes.  相似文献   
163.
BackgroundOcular episcleritis and uveitis are well-recognised extra-intestinal manifestations of Crohn's disease. Orbital myositis is rare: to our knowledge it has been associated with Crohn's disease in thirteen cases. Posterior scleritis, orbital myositis and Crohn's disease have been reported as coexisting in only two cases.Methods and resultsWe describe a third case, that of a 31-year old female with Crohn's colitis for 8 years, complicated by enteropathic arthritis and pyoderma gangrenosum. She presented with intense and intractable periorbital pain, particularly at night and worse on eye movements. B-scan ultrasonography confirmed posterior scleritis and treatment with high dose oral steroids (up to 60 mg prednisolone) was initially effective, but subsequently failed to control the inflammation. There was only a partial response to infliximab. Five months after presentation, diplopia developed, with failure of abduction of the left eye. MRI scan of the orbits confirmed orbital myositis involving the left lateral and medial rectus muscles. Pulsed intravenous methylprednisolone and six cycles of intravenous cyclophosphamide over a three month period resulted in complete resolution of inflammatory symptoms.ConclusionsThis case highlights a rare combination of ocular abnormality secondary to Crohn's disease and reports successful resolution with aggressive immunosuppressive therapy.  相似文献   
164.
Endotoxin is a component of gram-negative bacteria that causes hematologic and immunologic changes through its induction of cytokines. Interleukin-1 receptor antagonist (IL-1Ra) is a naturally occurring inhibitor of IL-1 that competes with IL-1 for occupancy of cell-surface receptors but possesses no agonist activity. We investigated the ability of human recombinant IL-1Ra to block the effects of low-dose endotoxin. Fourteen healthy male volunteers between 18 and 30 years old were injected intravenously with 3 ng/kg Escherichia coli endotoxin. Concurrent with the injections, nine volunteers received a 3-hour continuous intravenous infusion of IL-1Ra. The other five subjects were given a 3-hour infusion of saline. Volunteers injected with endotoxin experienced a threefold increase in circulating neutrophils over baseline. This neutrophilia was significantly reduced by 48% in subjects administered endotoxin plus IL-1Ra (P = .0253). Ex vivo mitogen-induced peripheral blood mononuclear cell proliferation decreased by greater than 60% at 3 and 6 hours after endotoxin injection (P = .0053). This endotoxin-induced reduction in mitogen response was reversed in subjects coinjected with IL-1Ra (P = .0253). Endotoxin-induced symptoms, fever, and tachycardia were unaffected by IL-1Ra. IL-1 appears to be an important mediator in endotoxemia because some of its hematologic and immunomodulatory effects can be blocked by IL-1Ra.  相似文献   
165.
STUDY OBJECTIVES: This study examines long-term trends in incidence rates of hospitalized pulmonary sarcoidosis in a large cohort of Navy personnel, and evaluates the possible relationship of sarcoidosis with occupation. DESIGN: Incidence rates of first hospitalizations were determined for black and white male Navy enlisted personnel on active duty from 1975 to 2001. SETTING: Navy service includes a potential for exposure to a variety of substances, including nonskid coatings used on ship decks that may be aerosolized during removal. Particulate matter containing aluminum, titanium, and silicates has been identified in nonskid samples. Specific occupational groups may have had greater exposure potential than others. PATIENTS OR PARTICIPANTS: Hospitalized cases included sarcoidosis (n = 674), asthma (n = 3,536), emphysema and chronic bronchitis (n = 1,103), respiratory conditions due to fumes and vapors (n = 61), and pneumoconiosis (n = 51) observed in 9,953,607 person-years of active-duty service. INTERVENTIONS: None. However, improvements were made in personal protective gear and other countermeasures to prevent or limit respiratory exposures during service. MEASUREMENTS AND RESULTS: Annual overall hospitalized sarcoidosis incidence rates per 100,000 were 24.9 for black men and 3.5 for white men (black/white ratio of 7.1, p < 0.0001). Annual incidence rates in blacks declined markedly, particularly since 1989, but the black/white ratio remained high through 1999. Occupational associations were present in blacks and whites. Black ship's servicemen (23 cases) and aviation structural mechanics specializing in structures (12 cases) had more than twice the expected incidence rate compared to all blacks, and white mess management specialists (15 cases) had twice the overall white incidence rate. CONCLUSIONS: There was a steep decline in incidence of hospitalized sarcoidosis in blacks in the Navy. Occupational associations suggest the possibility that a dust or moisture-related lung disease may have been erroneously classified as sarcoidosis, or, alternatively, that sarcoidosis had a previously unrecognized occupational component.  相似文献   
166.
Ritz  J; Schlossman  SF 《Blood》1982,59(1):1-11
The generation of murine monoclonal antibodies reactive with human leukemia and lymphoma cells has recently led to clinical trials that have begun to evaluate the use of these reagents in the treatment of various leukemias and lymphomas. Several of these studies have demonstrated that infusion of monoclonal antibody can cause the rapid and specific clearance of leukemic cells from the peripheral blood. Intravenously administered antibody also rapidly binds to bone marrow lymphoblasts, and in one instance, has resulted in the partial regression of tumor cell infiltrates in lymph nodes and skin. Unfortunately, clinically significant responses have not in general been achieved, but these clinical studies have identified specific factors that result in the development of resistance to antibody- mediated lysis in vivo. These factors include the presence of circulating antigen, antigenic modulation, reactivity of monoclonal antibody with normal cells, immune response to murine antibody, and the inefficiency of natural immune effector mechanisms. Current research is now being directed towards developing methods to circumvent each of these obstacles. Future clinical studies utilizing antibodies in vitro or with different specificity may demonstrate greater therapeutic efficacy. In addition, monoclonal antibodies can be used as carriers of other cytotoxic agents and in conjunction with other agents that will reduce the total load. Monoclonal antibodies represent new and powerful reagents that may in the near future become an additional therapeutic modality for patients with malignant disease.  相似文献   
167.

Background

Failed extubation and delayed tracheostomy contribute to poor outcomes in patients with a traumatic spinal cord injury (SCI). We determined if the level and completeness of SCI predict the need for tracheostomy.

Methods

Data from 256 patients with SCI between C1 and T3 with or without tracheostomy were retrospectively analyzed. Logistic regression identified predictors for tracheostomy. Data are presented as raw percentage or odds ratio (OR) with 95% confidence interval. P < .05 indicates significance.

Results

Complete spinal cord injuries were common in patients requiring tracheostomy (55% vs 18%, P < .05), and predicted the need for tracheostomy (OR: 6.4 (3.1 to 13.5), P < .05). An injury above C6 predicted the need for tracheostomy in patients with complete injury (OR: 3.7 (1 to 11.9), P < .05), but not incomplete injury (OR: .7 (.3 to 1.9); P = .53).

Conclusion

Tracheostomy is unlikely in patients with incomplete SCI, regardless of the level of injury. Patients with complete SCI above C6 are likely to require tracheostomy.  相似文献   
168.
ObjectiveTo create a summary of training, education, and experience by pharmacy officer rank (colonel, lieutenant colonel, major, and captain) to produce information for senior pharmacy leaders to describe active duty army pharmacy officers and for junior army pharmacy officers to use for individual career planning.MethodsA 32-question, anonymous, and voluntary survey was developed. Active duty army pharmacy officers were able to complete the survey via the government website, Intelink. The survey was open for 6 weeks during the summer of 2017.ResultsThe survey was completed by 62% of active duty army pharmacy officers. The responses were used to create a summary of training, education, and experience by pharmacy officer rank.ConclusionThe survey was successful in capturing information relating to training, education, and experience by rank, thereby providing useful quantifiable information to describe army pharmacy officer careers. These results may prove valuable to those interested in pharmacy careers in the military, and they create an opportunity to illustrate the distinct profession of army pharmacy officers.  相似文献   
169.
170.
Heparin-induced thrombocytopenia (HIT) is a rare, potentially life-threatening condition secondary to unfractionated heparin or low molecular weight heparin exposure. This immune-mediated drug reaction manifests as thrombocytopenia with a paradoxical hypercoagulable state that can result in life-threatening thrombosis. It is imperative to ensure cessation of heparin-based products as soon as HIT is identified. Traditional treatment options include argatroban, bivalirudin, fondaparinux, and danaparoid with a transition to warfarin upon platelet recovery. These anticoagulants are notwithstanding limitations including parenteral administration and routine laboratory monitoring leading to prolonged hospitalizations, emphasizing the need for new therapies. Direct oral anticoagulants (DOACs) have been increasingly investigated for the management of HIT and may overcome the aforementioned challenges of current therapies. The objective of this narrative review is to summarize the current HIT guidelines, discuss limitations to contemporary treatment options, provide insight into the emerging evidence for the DOACs rivaroxaban, apixaban, and dabigatran, and conclude with a clinical summary for their use in this setting. The PubMed, Google Scholar, and MEDLINE databases were searched for peer-reviewed literature from January 1, 2012, to June 31, 2018. Twenty-seven articles met inclusion criteria for review: 1 prospective trial, 5 retrospective cohort studies, and 21 case reports totaling 104 patients treated with a DOAC for HIT. The DOACs prevented new and recurrent thrombosis in 98% (n=102) of cases, and bleeding complications occurred in 3% (n=3). While current literature remains limited, it is suggestive of a potential role of DOACs for HIT, which has led to their integration into the 2018 American Society Hematology Guidelines with a conditional recommendation.  相似文献   
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