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Annals of Nuclear Medicine - Suspected serious disease (SSD) is a disease designation often given to patients with one or more non-specific symptoms of severe disease that could be due to cancer;...  相似文献   
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Hypoxaemia in association with acute respiratory failure continues to be a severe problem in some intensive care patients. Among strategies proposed, we want to focus attention on differential ventilation with selective PEEP, administered in the lateral position. This ventilation technique has proved successful in the treatment of refractory hypoxaemia due to severe bilateral lung disease.The rationale of this concept is briefly presented in this paper, where the main emphasis is laid on the practical aspects of its clinical application. Two case reports are included as examples of our experiences.  相似文献   
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Selective targeting of endothelial cells in tumor vessels requires delineation of key molecular events in formation and survival of blood vessels within the tumor microenvironment. To this end, proteins transiently up-regulated during vessel morphogenesis were screened for their potential as targets in antiangiogenic tumor therapy. The molecular chaperone alphaB-crystallin was identified as specifically induced with regard to expression level, modification by serine phosphorylation, and subcellular localization during tubular morphogenesis of endothelial cells. Small interfering RNA-mediated knockdown of alphaB-crystallin expression did not affect endothelial proliferation but led to attenuated tubular morphogenesis, early activation of proapoptotic caspase-3, and increased apoptosis. alphaB-crystallin was expressed in a subset of human tumor vessels but not in normal capillaries. Tumors grown in alphaB-crystallin(-/-) mice were significantly less vascularized than wild-type tumors and displayed increased areas of apoptosis/necrosis. Importantly, tumor vessels in alphaB-crystallin(-/-) mice were leaky and showed signs of caspase-3 activation and extensive apoptosis. Ultrastructural analyses showed defective vessels partially devoid of endothelial lining. These data strongly implicate alphaB-crystallin as an important regulator of tubular morphogenesis and survival of endothelial cell during tumor angiogenesis. Hereby we identify the small heat shock protein family as a novel class of angiogenic modulators.  相似文献   
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Background and purpose

Internal fixation of hip fractures is a common and important procedure that orthopedic surgeons must master early in their career. Virtual-reality training could improve initial skills, and a simulation-based test would make it possible to ensure basic competency of junior surgeons before they proceed to supervised practice on patients. The aim of this study was to develop a reliable and valid test with credible pass/fail standards.

Methods

20 physicians (10 untrained novices and 10 experienced orthopedic surgeons) each performed 3 internal fixation procedures of an undisplaced femoral neck fracture: 2 hook-pins, 2 screws, and a sliding hip screw. All procedures were preformed on a trauma simulator. Performance scores for each procedure were obtained from the predefined metrics of the simulator. The inter-case reliability of the simulator metrics was explored by calculation of intra-class correlation coefficient. Validity was explored by comparison between novices’ and experts’ scores using independent-samples t-test. A pass/fail standard was set by the contrasting-groups method and the consequences were explored.

Results

The percentage of maximum combined score (PM score) showed an inter-case reliability of 0.83 (95% CI: 0.65–0.93) between the 3 procedures. The mean PM score was 30% (CI: 7–53) for the novices and 76% (CI: 68–83) for the experienced surgeons. The pass/fail standard was set at 58%, resulting in none of the novices passing the test and a single experienced surgeon failing the test.

Interpretation

The simulation-based test was reliable and valid in our setting, and the pass/fail standard could discriminate between novices and experienced surgeons. Potentially, training and testing of future junior surgeons on a virtual-reality simulator could ensure basic competency before proceeding to supervised practice on patients.Worldwide, hip fractures account for substantial healthcare costs and high mortality, morbidity, and reoperation rates. Fractures are often treated with different types of internal fixation, which is a great contributor to training of surgical skills through the principle of the master-apprentice model. This model is not without risk, though. Inexperienced trainees contribute to a higher rate of re-admissions and reoperations (Palm et al. 2007, Leblanc et al. 2013).A review of 609 studies found that virtual-reality simulation training improved operative skills (Cook et al. 2011), and simulation-based training in orthopedic surgery is starting to emerge. Most of the development is in arthroscopy, but simulation-based training in fracture fixation is also being developed (Blyth et al. 2007, 2008, Mabrey et al. 2010, Atesok et al. 2012, Rambani et al. 2013). Current papers describe the simulators and explore construct validity of the simulator metrics (Tillander et al. 2004, Froelich et al. 2011). Reliable and valid tests with credible pass/fail standards are necessary to ensure basic competency of trainees before allowing them to proceed to supervised practice on patients (Stefanidis et al. 2012a, Konge et al. 2013).The objective of this study was to develop a test, to explore the reliability of this test, and to gather validity evidence. Furthermore, we wanted to establish a credible pass/fail standard and explore the consequences of this standard. The research questions were: (1) Which simulator metrics were able to discriminate between novices and experienced orthopedic surgeons?; (2) How many procedures on the simulator must be performed to ensure sufficient reliability?; and (3) What was a credible pass/fail standard in the test?  相似文献   
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Purpose

Physical illness has been shown to be a risk factor for suicidal behaviour in older adults. The association between functional disability and suicidal behaviour in older adults is less clear. The aim of this study was to examine the relationship between functional disability and death wishes in late life.

Methods

Data from 11 population studies on depression in persons aged 65 and above were pooled, yielding a total of 15,890 respondents. Level of functional disability was trichotomised (no, intermediate, high). A person was considered to have death wishes if the death wish/suicidal ideation item of the EURO-D scale was endorsed. Odds ratios for death wishes associated with functional disability were calculated in a multilevel logistic regression model.

Results

In total, 5 % of the men and 7 % of the women reported death wishes. Both intermediate (OR 1.89, 95 % CI 1.42; 2.52) and high functional disability (OR 3.22, 95 % CI 2.34; 4.42) were associated with death wishes. No sex differences could be shown. Results remained after adding depressive symptoms to the model.

Conclusions

Functional disability was independently associated with death wishes in older adults. Results can help inform clinicians who care for older persons with functional impairment.  相似文献   
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