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41.
Paul Lombardo   《Radiography》2006,12(4):332-338
The Australian higher education system is in a state of great change. The Federal education minister, Dr Brendan Nelson, has indicated that he intends to continue introducing far-reaching reforms that will impact significantly on how universities conduct teaching and research. The future allocation of government funding for university programs, including those in medical radiation, will have a significant effect on how those programs are delivered and could even determine whether programs remain viable. There will be a financial imperative for academic departments to strengthen research activity and to obtain funding from non-government sources, such as full-fee paying students, in order to generate enough income to cover program delivery. Medical radiation education in Australia is also facing many other challenges. Some of these are longstanding, such as the high cost of medical radiation program delivery, poor levels of research activity and difficulty in recruiting and retaining academic staff. Other problems have arisen recently, such as increased competition for students and a critical shortage of available training placements in clinical practice. The aim of this paper is to raise and explore these issues from a university perspective.  相似文献   
42.
原北京医科大学(现为北京大学医学部)从20世纪90年代初开始,积极寻求与美国中华医学基金会的合作以促进医学伦理学的学科发展和国际化水平的提高。十几年来,北京大学医学部作为基地和依托极大地支持和引领了我国医学伦理学的教学改革与发展,增强了相关人员的医学伦理意识以及医学伦理学理论对实践的指导作用,促进了伦理学知识和能力的培训,提升了我国生物医学科研伦理的实力,奠定了医学伦理学继续教育的基础,使医学伦理学实现了系统性和跨越式的发展。  相似文献   
43.
本文综述了近10年来黄栌中漆黄索的提取工艺和测定方法的研究进展,并对各种提取工艺和测定方法进行了评价。为更好地开发利用漆黄素提供参考。  相似文献   
44.
The evaluation of healthcare practice and service delivery is fraught with difficulties. Service development and / or delivery occurs within socially dynamic settings which are in a continual state of change. Service development also often involves large elements of improvisation. The action research approach is useful for health service research, as it supports collaboration between researchers and practitioners, and not only allows but makes explicit that the action researcher has both roles within the setting being studied. This paper discusses action research methodology and offers insight into principles that favor its use for service delivery development. This includes consideration of the interactive variables within studies of health care systems and the importance of evaluating relationships between stakeholders to understand how these factors or variables, which cannot be controlled for, are responsible for successful development of the service. Action research facilitates change and helps bridge the heory--practice gap. With the current dynamic changes within both the pharmacy profession and national health services, researchers may find the action research technique of value when considering new roles and innovative ways of engaging in collaborative, multi-disciplinary working to improve delivery of patient care.Accepted july 2004  相似文献   
45.
狂犬病病毒(RV)是一种高度嗜神经性病毒,由RV引发的狂犬病通常是一种急性致死性神经系统损伤性疾病。RV通过周围神经末梢和中枢神经系统(CNS)的神经元进行病毒的复制和传播。绝大多数狂犬病例CNS病理学表现为急性脑脊髓炎,常常没有显著的显微镜下改变,脑部可以轻度肿胀,脑膜和脑实质血管轻度充血并伴有少量炎症细胞浸润,这也是其他急性病毒性脑炎常见的共同表现。  相似文献   
46.
兔精原干细胞培养及生物学特征的初步研究   总被引:2,自引:0,他引:2  
目的:建立精原干细胞的培养方法并对培养细胞的生物学特征进行研究.方法:用饲养层和无饲养层两种方法培养幼家兔精原干细胞,在倒置相差显微镜下观察培养细胞的生长和形态变化,并对细胞的糖原、脂质及c-kit受体的细胞化学和免疫细胞化学染色结果进行分析.结果:成功的分离并培养幼家兔精原干细胞.在培养细胞中精原干细胞为主体细胞,并可见少量间质细胞.根据精原干细胞体积大小和形态特点,可分为大、小两种类型.PAS染色,精原干细胞胞质呈阳性反应;免疫细胞化学染色显示,体积较小的精原干细胞c-kit受体呈强阳性反应,体积较大的大精原干细胞呈弱阳性反应;间质细胞PAS染色和c-kit受体染色呈阴性反应,而脂质染色呈强阳性反应.精原干细胞培养无论有无饲养层,均能呈集落状生长,但有饲养层的培养,细胞的生长明显优于无饲养层培养.结论:青春期前的睾丸生精小管是精原干细胞最集中、数量最多,且容易获取分离的部位;精原干细胞的成功培养为今后重建完整的生精细胞系的治疗性移植和对这类定向干细胞的发育及分化潜能的研究提供了细胞模型.  相似文献   
47.
BACKGROUND: Although pedophilia is of high public concern, little is known about underlying neural mechanisms. Although pedophilic patients are sexually attracted to prepubescent children, they show no sexual interest toward adults. This study aimed to investigate the neural correlates of deficits of sexual and emotional arousal in pedophiles. METHODS: Thirteen pedophilic patients and 14 healthy control subjects were tested for differential neural activity during visual stimulation with emotional and erotic pictures with functional magnetic resonance imaging. RESULTS: Regions showing differential activations during the erotic condition comprised the hypothalamus, the periaqueductal gray, and dorsolateral prefrontal cortex, the latter correlating with a clinical measure. Alterations of emotional processing concerned the amygdala-hippocampus and dorsomedial prefrontal cortex. CONCLUSIONS: Hypothesized regions relevant for processing of erotic stimuli in healthy individuals showed reduced activations during visual erotic stimulation in pedophilic patients. This suggests an impaired recruitment of key structures that might contribute to an altered sexual interest of these patients toward adults.  相似文献   
48.
The mechanism of release from sustained-release adinazolam mesylate tablets was assessed by the Higuchi equation and by analysis of drug release profiles through 60% released using the Peppas equation. Computed values of the diffusional exponent, n, ranged from 0.59 to 0.66. Values of n in this range are consistent with a mixed mechanism of release, with diffusion of drug through the hydrated polymer matrix and relaxation of this matrix being the principal processes controlling release. The rate of in vitro drug release was increased for half tablets relative to whole tablets and is attributed to an increase in the surface to volume ratio of half tablets of about 16%. This increase in surface-to-volume ratio of half tablets was reflected by an increase in the constant, k, from the Peppas equation of 20–23% and by an increase in the slope of Higuchi plots of 12–18% for four lots of tablets. In vivo/in vitro relationships from two bioavailability studies were thoroughly evaluated. Using either a linear or a quadratic relationship, an in vivo/in vitro correlation exists for sustained-release adinazolam mesylate tablets.  相似文献   
49.
Between 23 and 70% of occupants involved in frontal impacts sustain cervical spine injuries, many with neurological involvement. It has been hypothesized that cervical spinal cord compression and injury may explain the variable neurological profile described by frontal impact victims. The goals of the present study, using a biofidelic whole cervical spine model with muscle force replication, were to quantify canal pinch diameter (CPD) narrowing during frontal impact and to evaluate the potential for cord compression. The biofidelic model and a sled apparatus were used to simulate frontal impacts at 4, 6, 8, and 10 g horizontal accelerations of the T1 vertebra. The CPD was measured in the intact specimen in the neutral posture (neutral posture CPD), under static sagittal pure moments of 1.5 Nm (pre-impact CPD), during dynamic frontal impact (dynamic impact CPD), and again under static pure moments following each impact (post-impact CPD). Frontal impact caused significant (P<0.05) dynamic CPD narrowing at C0-dens, C2-C3, and C6-C7. The narrowest dynamic CPD was observed at C0-dens during the 10 g impact and was 25.9% narrower than the corresponding neutral posture CPD. Interpretation of the present results indicate that the neurological symptomatology reported by frontal impact victims is most likely not due to cervical spinal cord compression. Cord compression due to residual spinal instability is also not likely.  相似文献   
50.
Diseases like rotavirus afflict both upper- and lower-income countries, but most serious illnesses and deaths occur among the latter. It is a vital public health issue that vaccines for these types of global diseases can recover research and development (R&D) costs from high-priced markets quickly so that manufacturers can offer affordable prices to lower-income nations. Cost recovery depends on how high R&D costs are, and this study attempts to replace high, unverified estimates with lower, more verifiable estimates for two new vaccines, RotaTeq (Merck) and Rotarix (GlaxoSmithKline or GSK), based on detailed searches of public information and follow-up interviews with senior informants. We also offer a new perspective on “cost of capital” as a claim for recovery from public bodies. Our estimates suggest that companies can recover all fixed costs quickly from affluent markets and thus can offer these vaccines to lower-income countries at prices they can afford. Better vaccines are a shared project between companies and public health agencies; greater transparency and consistency in reporting of R&D costs is needed so that fair prices can be established.  相似文献   
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