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Mice transgenic with the human poliovirus receptor gene develop clinical signs and neuropathology similar to those of human poliomyelitis when neurovirulent polioviruses are inoculated into the central nervous system (CNS). Factors contributing to disease severity and the frequencies of paralysis and mortality include the poliovirus strain, dose, and gender of the mouse inoculated. The more neurovirulent the virus, as defined by monkey challenge results, the higher the rate of paralysis, mortality, and severity of disease. Also, the time to disease onset is shorter for more neurovirulent viruses. Male mice are more susceptible to polioviruses than females. TGM-PRG-3 mice have a 10-fold higher transgene copy number and produce 3-fold more receptor RNA and protein levels in the CNS than TGM-PRG-1 mice. CNS inoculations with type III polioviruses differing in relative neurovirulence show that these mouse lines are similar in disease frequency and severity, demonstrating that differences in receptor gene dosage and concomitant receptor abundance do not affect susceptibility to infection. However, there is a difference in the rate of accumulation of clinical signs. The time to onset of disease is shorter for TGM-PRG-3 than TGM-PRG-1 mice. Thus, receptor dosage affects the rate of appearance of poliomyelitis in these mice.  相似文献   
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个体化下肢小腿假肢接受腔设计的生物力学评价技术研究   总被引:3,自引:0,他引:3  
作为传递体重、固定假肢的部件 ,接受腔对于小腿假肢使用的舒适性和方便程度有决定性的作用。本研究建立了基于有限元应力分析的小腿假肢生物力学评价技术平台 ,实现了小腿残端 /接受腔 3D几何建模与信息交互、三维有限元自动建模及应力分析。 3D模型与信息交互的实现基于得到广泛支持的OpenGL技术 ,有限元模型的构建采用了专门针对小腿残端 /接受腔结构特点的自动建模方法 ,通过构建档案数据库系统作为整个系统的操作平台。该技术平台可与现有的CAD/CAM系统相结合 ,为接受腔的个体化设计提供生物力学定量化依据。其临床应用将改善传统的设计流程 ,提高设计效率。同时 ,它也是未来构建接受腔设计专家 /智能系统的基础。  相似文献   
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The Coping Inventory for Stressful Situations (CISS; Endler & Parker, 1990) is a self-report measure of Emotion-, Task-, and Avoidance-oriented coping. The psychometric properties of the CISS were evaluated in a large sample of outpatients with major depressive disorder (N = 298). The CISS scales demonstrated good reliability and support for their factorial validity was obtained. Relationships between the CISS scales and the broad personality domains from the five-factor model of personality, as well as two measures of emotional distress, were examined. Less-adaptive coping strategies (i.e., Emotion-oriented coping) were associated with less-adaptive personality traits (i.e., Neuroticism) and with psychological distress (i.e., Depression), whereas the reverse was found regarding adaptive coping strategies (i.e., Task-orientated coping). The incremental validity of the CISS was demonstrated by multiple-regression analyses that found two CISS scales accounted for significant variance in psychological distress beyond that contributed by the demographic and personality variables.  相似文献   
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碱离子水饮用后血小板聚集率的的变化(附30例报告)   总被引:1,自引:0,他引:1  
目的:报告30例饮用豪斯牌碱离子水前、后血小板聚集率的变化。方法:饮用碱离子水前、后(2~3月,>3~6月)作比浊法血小板聚集试验,以1分钟、5分钟及5分钟内最大聚集率(Max%)为指标,同时检测部分血粘度指标及凝血因子,并用自动生化仪检测血糖、血脂、主要电解质及部分肝、肾功能。结果:饮碱离子水后,血小板聚集率明显下降,而以疾病组(Max>80%)下降尤为明显,P均<0.001。饮碱离子水后血小板聚集率的下降,部分可能与损伤的血管内皮得到修复有关。主要电解质及部分肝、肾功能无明显异常改变。结论:由于心、脑血管血栓性疾病患者血小板聚集率多明显升高,饮碱离子水后血小板聚集率明显下降,且长期饮用对主要电解质及部分肝、肾功能无明显异常改变,作者认为碱离子水使用方例、安全、有效、价廉,因而对心、脑血管血栓性疾病防治方面可能是一种积极的辅助方法,值得临床进一步探索。  相似文献   
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INTRODUCTION: A phase I, open-label, multiple dose, dose-escalation clinical study was conducted to assess the safety, tolerability, maximum tolerated dose, and potential chemopreventive effect of myo-inositol in smokers with bronchial dysplasia. MATERIALS AND METHODS: Smokers between 40 and 74 years of age with >or= 30 pack-years of smoking history and one or more sites of bronchial dysplasia were enrolled. A dose escalation study ranging from 12 to 30 g/d of myo-inositol for a month was first conducted in 16 subjects to determine the maximum tolerated dose. Ten new subjects were then enrolled to take the maximum tolerated dose for 3 months. The potential chemopreventive effect of myo-inositol was estimated by repeat autofluorescence bronchoscopy and biopsy. RESULTS: The maximum tolerated dose was found to be 18 g/d. Side effects, when present, were mild and mainly gastrointestinal in nature. Using the regression rate of the placebo subjects from a recently completed clinical trial with the same inclusion/exclusion criteria as a comparison, a significant increase in the rate of regression of preexisting dysplastic lesions was observed (91% versus 48%; P = 0.014). A statistically significant reduction in the systolic and diastolic blood pressures by an average of 10 mm Hg was observed after taking 18 g/d of myo-inositol for a month or more. CONCLUSION: myo-Inositol in a daily dose of 18 g p.o. for 3 months is safe and well tolerated. The potential chemopreventive effect as well as other health benefits such as reduction in blood pressure should be investigated further.  相似文献   
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Aim: Most national guidelines recommend psychological therapy for people with first‐episode psychosis (FEP) but interventions proven effective in randomized control trials (RCTs) conducted in research settings do not always translate effectively to real‐world clinical environments. In a limited health system, it is important to understand the system and patient barriers to participation in effective treatment. We sought to determine what patient characteristics influenced clinicians' decision to refer or not to refer to group cognitive behavioural therapy for FEP and what characteristics were associated with those referred attending/not attending and adhering/not adhering to the programme. Methods: Between 2006 and 2008, all cases of confirmed FEP from a defined geographical region were examined using the Structured Clinical Interview for DSM‐IV‐TR Axis I Disorders for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM‐IV) diagnoses, the Scale for Assessment of Positive Symptoms, Scale for Assessment of Negative Symptoms, Calgary Depression Scale for Schizophrenia and Birchwood Insight Scale. Duration of untreated psychosis was established using the Beiser Scale. Results: Of the 124 (77 males, 47 females) people in the final sample, 88 (72%) were referred for cognitive behavioural therapy (CBT), 52 (59%) attended and 12 (23%) did not complete CBT. Those with higher levels of insight into the need for treatment (U = 740.00, z = −2.63, P = 0.008) and higher levels of positive symptoms (t (120) = −3.064, P = 0.003) were more likely to be referred to CBT. Those with higher educational attainment (χ2 = 9.48, P = 0.03) and fewer negative symptoms, particularly in relation to global attention (t (85) = 2.32, P = 0.03), were more likely to attend and complete CBT. Conclusion: Within an early intervention service for FEP, it appears that individuals with less education, more negative symptoms and less insight experienced significant barriers to successfully completing group CBT. More information for referring clinicians about the benefits of CBT for FEP could help increase referral rates. Assertive outreach for people at risk of disengaging or non‐adherence should also be considered.  相似文献   
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Fistulae between the aorta and adjacent structures are a rare, emergent, and potentially life-threatening process. Most commonly, aortic fistulae arise secondarily as a complication of prior aortic surgery with fistulization to adjacent structures. Rarely, a primary fistula may arise from the aorta in the setting of a pre-existing aneurysm or from a mass, inflammation, or infection. Although the incidence of aortic fistulae remains low, the frequency continues to increase as aortic surgical interventions and post-surgical follow-up with imaging become more common. Computed tomography (CT) is the modality of choice in evaluating the patient with suspected aortic fistula because of its accessibility and short scan time. In addition, CT allows for more clear depiction of para-aortic or intra-aortic gas than ultrasound or magnetic resonance (MR). This gas may be the first clue of a fistula. Given the high mortality associated with aortic fistulae, familiarity with the imaging findings of the spectrum of aortic fistulae is essential knowledge in the emergency setting. This review will discuss the imaging appearance of aortic and arterial fistulae to the bronchi, esophagus, gastrointestinal tract, ureters, and veins on CT.  相似文献   
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