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51.
Research is proving that the effects of various mediators and changes in microcirculation bring about the cellular and metabolic consequences recognized clinically as shock. In this article, the authors approach diagnosis and treatment of the different types of shock through evaluation of hemodynamic variables. They summarize underlying causes of shock, the signs of its progressive stages, and diagnostic studies needed to guide treatment decisions.  相似文献   
52.
Abstract

This article explores issues of historical disputes between nurses and midwives based in Chile. The interaction of these two professions in that country has become an arena of competition which leads to conflicts periodically, such as those related to the ownership of the care of new-borns, and that of projects aimed at relieving nurse shortages by enhancing midwives’ nursing skills. Specifically, this article aims to build on historical and contemporary resources analysed from a sociological perspective, and present comparatively a rationale concerning nursing/midwifery jurisdictional conflicts through a social history account. Our analysis suggests that nurses/midwives interaction has been shaped by social-historical transformations and the continuous evolution of the healthcare system as a whole, resulting in a race towards technologisation. These interprofessional conflicts can be explained partly by mechanisms of boundary expansion within an organisational/interpretive domain, as well as varying degrees of medicalisation; and partly by a competition possibly originating from a middle-class consciousness. An eventual merger of the two professions might lead to the enhancement of the political power of the caring professions and integrated care.  相似文献   
53.
54.
The ability to reconstruct complex facial injuries is still a considerable challenge despite the development of microsurgical techniques. The reconstructive options for conditions such as panfacial burns are severely limited. The result after multiple surgical procedures in this group is often poor in terms of function and cosmesis. Facial transplantation provides a potential solution, but opinion is currently divided about the extent to which the potential benefits to the quality of life can be justified when weighed against the technical, psychological and immunological risks. This paper reviews the current status of the debate and argues that a rigorous research strategy is the only logical basis for countering the ethical objections to a procedure that offers considerable benefits over existing reconstructive options.  相似文献   
55.
介绍成果导向教育教学理念,详细阐述“线上+线下”混合式教学设计过程,包括设计流程、教学目标、课程实施、学习成果及教学评价等,以期激发学生学习兴趣,提高教学效果。  相似文献   
56.
通过问卷调查的方式对沧州市4所高等院校图书馆数字资源的使用情况进行了统计,分析了高校图书馆数字资源利用率偏低的一些深层次原因,并从认知的角度对提高数字资源利用率提出建议.  相似文献   
57.
Dosimetrists, physicists, and physicians rely heavily upon digital imaging modalities in their daily work. In the current healthcare marketplace, many radiotherapy facilities operate satellite centers or may be undergoing mergers with other service providers in their community. As a consequence, the development of network-based radiotherapy image communication may yield a significant impact on the clinical operation of such centers. Digital image networking will become an everyday tool in radiotherapy treatment planning in the near future. As responsible users of this technology, an accurate perception of what the network does is essential and enhances our ability to utilize it. This article presents a review of the network architecture and transmission standards necessary for understanding and developing a radiotherapy image network.  相似文献   
58.
PurposeTo evaluate the utility of cone-beam computed tomography (CT) in patients undergoing prostatic artery (PA) embolization (PAE) for benign prostatic hyperplasia.Materials and MethodsFrom January 2012 to January 2013, 15 patients (age range, 59–81 y; mean, 68 y) with moderate- or severe-grade lower urinary tract symptoms, in whom medical management had failed were enrolled in a prospective United States trial to evaluate PAE. During pelvic angiography, 15 cone-beam CT acquisitions were performed in 11 patients, and digital subtraction angiography was performed in all patients. Cone-beam CT images were reviewed to assess for sites of potential nontarget embolization that impacted therapy, a pattern of enhancement on cone-beam CT suggesting additional PAs, confirmation of prostatic parenchymal perfusion before embolization, and contralateral prostatic parenchymal enhancement.ResultsCone-beam CT was successful in 14 of 15 acquisitions, and PAE was successful in 14 of 15 patients (92%). Cone-beam CT provided information that impacted treatment in five of 11 patients (46%) by allowing for identification of sites of potential nontarget embolization. Duplicated prostatic arterial supply and contralateral perfusion were each identified in 21% of patients (three of 11). Prostatic perfusion was confirmed before embolization in 50% of acquisitions (seven of 14).ConclusionsCone-beam CT is a useful technique that can potentially mitigate the risk of nontarget embolization. During treatment, it can allow for the interventionalist to identify duplicated prostatic arterial supply or contralateral perfusion, which may be useful when evaluating a treatment failure.  相似文献   
59.
The purpose of this report is to present a mathematical model relating changes in grey values to changes of thicknesses of a stepwedge. Radiographs of a stepwedge were obtained through a limited exposure range on a single Kodak 6100 charge-coupled device detector at 63 kVp and 70 kVp. Grey values from each step were evaluated relative to the corresponding step thickness. All possible regression fits were evaluated based on their coefficient of determination (R2) value and their mean squared errors (MSEs) relative to the original thickness. For all exposure settings, the fifth-degree polynomial was the best possible fit, with the highest R2 value and the lowest MSE.  相似文献   
60.
One fundamental difference between normal and transformed cells is the way they interact with their immediate environment. Exploring this difference is crucial for understanding the pathobiology of cancer progression. Benign epithelial tumors are constrained by a surrounding stroma consisting, among other cells, of fibroblasts embedded within fibrillar three-dimensional matrices. However, at a critical point in tumor progression, tumor cells become altered and overcome the barrier, inducing changes in the stroma, which promote, rather than impede, tumor progression. Inherited or acquired genetic aberrations affecting mammary gland epithelia are usually blamed for promoting neoplasia in individuals at high risk for breast cancer. However, in addition to these epithelial aberrations certain individuals possess permissive breast stroma. The occurrence of this permissive stroma results in a predisposition for cancer initiation or progression. Here we review stromagenic stages, experimental 3D systems, and discuss digital imaging analyses suitable for uncovering the mechanisms behind fibroblastic breast stromagenesis.  相似文献   
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