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961.
Behavioural changes in rats two weeks after inescapable shock stress were studied using a shuttle-box task (active avoidance/escape). Rats exposed to inescapable shock stress two weeks beforehand showed more frequent avoidance responses and greater within-group variation in both avoidance response and general activity during the test than rats in a control group. General activity during an unstressful period (before starting the test) did not differ significantly between groups. This relatively prolonged increase in responsiveness to external stimuli in the stressful context may be a useful experimental model of posttraumatic stress disorder, especially in relation to hypervigilance.  相似文献   
962.
963.
目的 探讨SHEL事故分析法在院前急救护理安全管理中的应用效果.方法 应用SHEL事故分析法对2010年1月至2011年12月院前急救护理工作中出现的25例次护理缺陷进行分析,制定护理安全管理措施并进行针对性的管理.结果 加强护理安全管理后,2012年1~12月发生护理缺陷4例次,较管理前(25例次)显著减少(P<0.05).结论 应用SHEL事故分析法对院前急救护理缺陷进行原因分析,针对性的制定护理安全管理措施,能明显降低护理缺陷的发生,保证护理安全.  相似文献   
964.
目的:观察猪胰弹性酶快速诱导建立兔囊状动脉瘤模型的形态学改变和早期病理学变化,探讨动脉瘤的创伤修复机制,为动脉瘤的治疗寻找新的切入点。方法:应用猪胰弹性酶消化兔右侧颈总动脉起始部建立动脉瘤模型,3 d、7 d、21 d灌注取出动脉瘤组织,采用病理学、免疫组织化学、脑血管造影技术研究该模型的影像学和病理学变化。结果:病理学观察发现动脉瘤顶部均有红血栓形成,血管内皮细胞消失,瘤壁完全缺失弹力层,载瘤动脉的弹力层在动脉瘤颈部突然消失,动脉瘤内膜逐渐增生,但仍缺乏弹力层,平滑肌细胞和胶原纤维增生明显。免疫组织化学均显示内膜VonWillebrand因子(vWF)染色阴性。对照组动物均形成动脉残端,动脉残腔内无或少量血栓,血管壁结构完整。造影显示21 d动脉瘤长径(6.40±1.62)mm,宽径(4.41±1.15)mm,瘤颈宽(5.30±2.51)mm,载瘤动脉直径(3.99±1.59)mm。结论:通过简单外科手术方法结合弹力酶消化局部血管壁,可以建立病理学和形态学上与人颅内动脉瘤相似的动脉瘤模型。动脉瘤模型早期存在一定的自身修复机制,内膜逐渐增生,以平滑肌细胞和胶原纤维增生为主,未见弹力纤维和内皮细胞增生修复。  相似文献   
965.
966.
《Vaccine》2015,33(16):1993-1998
ObjectiveAccording to the Health Belief Model (HBM), individual perceptions of susceptibility, severity, benefit, barrier, self-efficacy, and cues to action are associated with health actions. In this study, we investigated the perceptions and social factors that influence the intention to vaccinate children against influenza among parents of young Taiwanese children.MethodsA nationwide survey was performed using stratified random sampling to explore the beliefs, attitudes, and intentions of parents/main caregivers with regard to vaccinating children aged 6 months to 3 years against influenza. A questionnaire was developed based on the HBM and multivariate logistic regression analyses of 1300 eligible participants were used to identify significant predictors of the intention to vaccinate.ResultsGreater perceived benefit, cues to action, and self-efficacy of childhood vaccination against influenza were positively associated with the intention to vaccinate. Children's experience of influenza vaccinations in the past year was also a positive predictor. However, perceived susceptibility, perceived severity regarding influenza and perceived barriers to vaccination were not predictive of the intention to vaccinate.ConclusionIn addition to perceived benefits and cues to action, self-efficacy of parents/main caregivers was significantly predictive of their intention to accept influenza vaccination for their young children. These components of the HBM could be used in formulating strategies aimed at promoting the use of influenza vaccine.  相似文献   
967.
In Simian virus 40 (SV40) transgenic BALB/c WAP-T mice tumor development and progression is driven by SV40 tumor antigens encoded by inducible transgenes. WAP-T mice constitute a well characterized mouse model for breast cancer with strong similarities to the corresponding human disease. BALB/c mice mount only a weak cellular immune response against SV40 T-antigen (T-Ag). For studying tumor antigen specific CD8+ T-cell responses against transgene expressing cells, we created WAP-TNP mice, in which the transgene additionally codes for the NP118–126-epitope contained within the nucleoprotein of lymphocytic choriomeningitis virus (LCMV), the immune-dominant T-cell epitope in BALB/c mice. We then investigated in WAP-TNP mice the immune responses against SV40 tumor antigens and the NP-epitope within the chimeric T-Ag/NP protein (T-AgNP). Analysis of the immune-reactivity against T-Ag in WAP-T and of T-AgNP in WAP-TNP mice revealed that, in contrast to wild type (wt) BALB/c mice, WAP-T and WAP-TNP mice were non-reactive against T-Ag. However, like wtBALB/c mice, WAP-T as well as WAP-TNP mice were highly reactive against the immune-dominant LCMV NP-epitope, thereby allowing the analysis of NP-epitope specific cellular immune responses in WAP-TNP mice. LCMV infection of WAP-TNP mice induced a strong, LCMV NP-epitope specific CD8+ T-cell response, which was able to specifically eliminate T-AgNP expressing mammary epithelial cells both prior to tumor formation (i.e. in cells of lactating mammary glands), as well as in invasive tumors. Elimination of tumor cells, however, was only transient, even after repeated LCMV infections. Further studies showed that already non-infected WAP-TNP tumor mice contained LCMV NP-epitope specific CD8+ T-cells, albeit with strongly reduced, though measurable activity. Functional impairment of these ‘endogenous’ NP-epitope specific T-cells seems to be caused by expression of the programmed death-1 protein (PD1), as anti-PD1 treatment of splenocytes from WAP-TNP tumor mice restored their activity. These characteristics are similar to those found in many tumor patients and render WAP-TNP mice a suitable model for analyzing parameters to overcome the blockade of immune checkpoints in tumor patients.  相似文献   
968.
For characterizing the genetic mechanisms of complex diseases familial data with multiple correlated quantitative traits are usually collected in genetic studies. To analyze such data, various multivariate tests have been proposed to investigate the association between the underlying disease genes and the multiple traits. Although these multivariate association tests may have better power performance than the univariate association tests, they suffer from loss of testing power when the genetic models of the putative genes are misspecified. To address the problem, in this paper we aim to develop a family‐based robust multivariate association test. We will first establish the optimal multivariate score tests for the recessive, additive, and dominant genetic models. Based on these optimal tests, a maximum‐type robust multivariate association test is then obtained. Simulations are conducted to compare the power of our method with that of other existing multivariate methods. The results show that the robust multivariate test does manifest the robustness in power over all plausible genetic models. A practical data set is applied to demonstrate the applicability of our approach. The results suggest that the robust multivariate test is more powerful than the robust univariate test when dealing with multiple quantitative traits.  相似文献   
969.
We previously reported the financial data for the first 5 years of one of the author’s medical toxicology practice. The practice has matured; changes have been made. The practice is increasing its focus on office-based encounters and reducing hospital-based acute care encounters. We report the reimbursement rates and other financial metrics of the current practice. Financial records from October 2009 through September 2013 were reviewed. This is a period of 4 fiscal years and represents the currently available financial data. Charges, payments, and reimbursement rates were recorded according to the type and setting of the medical toxicology encounter: forensic consultations, outpatient clinic encounters, nonpsychiatric inpatient consultations, emergency department (ED) consultations, and inpatient psychiatric consultations. All patients were seen regardless of ability to pay or insurance status. The number of billed Current Procedural Terminology (CPT) codes for office-based encounters increased over the study period; the number of billed CPT codes for inpatient and ED consultations reduced. Office-based encounters demonstrate a higher reimbursement rate and higher payments. In the fiscal year (FY) of 2012, office-based revenue exceeded hospital-based acute care revenue by over $140,000 despite a higher number of billed CPT encounters in acute care settings, and outpatient payments were 2.39 times higher than inpatient, inpatient psychiatry, observation unit, and ED payments combined. The average payment per CPT code was higher for outpatient clinic encounters than inpatient encounters for each fiscal year studied. There was an overall reduction in CPT billing volume between FY 2010 and FY 2013. Despite this, there was an increase in total practice revenue. There was no change in payor mix, practice logistics, or billing/collection service company. In this medical toxicology practice, office-based encounters demonstrate higher reimbursement rates and overall payments compared to inpatient and ED consultations. While consistent with our previous studies, these differences have been accentuated. This study demonstrates the results of changes to the practice—reduced inpatient/ED consultations and increased outpatient encounters. These practice changes resulted in higher overall revenue despite a lower patient volume. In this analysis, the office-based practice of medical toxicology has higher reimbursement rates, nearly 2.5 times higher, when compared to hospital-based acute care consultations.  相似文献   
970.
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