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Objectives  

Restoration of stability and function of the shoulder.  相似文献   
67.
Lethal injuries of the thorax due to shots fired from blank cartridges calibre 8 mm are reported in three cases. The muzzle of the weapon was in contact with the left side of the breast (contact discharge) and injuries to bones were absent in all three cases. In two of the cases the pericardium was not involved but the anterior wall of the right heart ventricle was ruptured and death was due to cardiac tamponade. In the third case the pericardial sac and the left ventricle were both ruptured and the victim died due to rapid exsanguination. The cases demonstrate that the gas pressure from the exploding propellent of blank ammunition can be powerful enough to penetrate the thoracic wall. Received: 26 May 1997 / Received in revised form: 9 September 1997  相似文献   
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BACKGROUND: Quality of life (QOL) measures give patients the possibility to express subjective changes in wellbeing. We aimed to translate the radiation specific quality of life questionnaire (QOL-RTI) and the companion head and neck module (H&N) questionnaire into German and to test its reliability, validity and sensitivity. PATIENTS AND METHODS: After translation and final revisions based on qualitative interviews with ten patients, 97 head and neck cancer patients were screened for eligibility. Patients answered the 38 items questionnaire at baseline and twice in week 4 of radiotherapy for test-retest reliability. Internal consistency was calculated using Chronbach's alpha. Patients also completed the functional assessment of cancer tool plus head and neck (FACT-G plus H&N) for concurrent validity. Item analyses were performed to test the sensitivity. RESULTS: Chronbach's alpha yielded alpha = 0.85 for the QOL-RTI and alpha = 0.80 for the H&N module, test-retest reliability scores were r = 0.87 and r = 0.83, respectively. The correlation of the QOL-RTI plus H&N and the FACT plus H&N was r = 0.79. Questionnaire sensitivity was supported by significant changes in the mean score of 45.8% of the QOL-RTI items and 78.6% of the H&N items between baseline and week 4 of radiotherapy. CONCLUSIONS: The German version of the QOL-RTI was shown to be a reliable, valid and sensitive tool to assess the quality of life of patients undergoing radiotherapy. The H&N module is useful for patients undergoing treatment for head and neck cancer.  相似文献   
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The aim of this study was to differentiate normal, hypercellular, and neoplastic bone marrow based on its MR enhancement after intravenous administration of superparamagnetic iron oxides in patients with cancer of the hematopoietic system. Eighteen patients with cancer of the hematopoietic system underwent MRI of the spine before and after infusion of ferumoxides ( n=9) and ferumoxtran ( n=9) using T1- and T2-weighted turbo spin-echo (TSE) and short tau inversion recovery sequences (STIR). In all patients diffuse or multifocal bone marrow infiltration was suspected, based on iliac crest biopsy and imaging such as conventional radiographs, MRI, and positron emission tomography. In addition, all patients had a therapy-induced normocellular ( n=7) or hypercellular ( n=11) reconversion of the normal non-neoplastic bone marrow. The MRI data were analyzed by measuring pre- and post-contrast signal intensities (SI) of hematopoietic and neoplastic marrow and by calculating the enhancement as deltaSI(%) data and the tumor-to-bone-marrow contrast as contrast-to-noise ratios (CNR). Changes in bone marrow signal intensity after iron oxide administration were more pronounced on STIR images as compared with T1- and T2-weighted TSE images. The STIR images showed a strong signal decline of normal and hypercellular marrow 45-60 min after iron oxide infusion, but no or only a minor signal decline of neoplastic bone marrow lesions; thus, deltaSI% data were significantly higher in normal and hypercellular reconverted marrow compared with neoplastic bone marrow lesions ( p<0.05). Additionally, the contrast between focal or multifocal neoplastic bone marrow infiltration and normal bone marrow, quantified by CNR data, increased significantly on post-contrast STIR images compared with precontrast images ( p<0.05). Superparamagnetic iron oxides are taken up by normal and hypercellular reconverted bone marrow, but not by neoplastic bone marrow lesions, thereby providing significantly different enhancement patterns on T2-weighted MR images; thus, superparamagnetic iron oxides are useful to differentiate normal and neoplastic bone marrow and to increase the bone marrow-to-tumor contrast.  相似文献   
70.
PURPOSE: Important criteria for optimized stent implantation are high radial force and complete apposition of the stent itself. The aim of this study was to develop a simple method to assess these parameters under controlled experimental conditions and to compare vascular stents of different designs with regard to these parameters. MATERIALS AND METHODS: Five balloon-expandable stents of different designs (Jostent Flex, MAC stent, ML-Tristar, ML-Ultra, and S670) were tested. Fourteen stents of each type were implanted in a curved plastic vessel model (curve radius, 10 mm; lumen diameter, 3.5 mm) with use of a balloon inflation pressure of 12 atm. Part of the model was a nonflexible eccentric stenosis which was 2 mm or 8 mm in length. After stent implantation, a stenosis of 10%-70% was induced and radial force of the stent struts was measured at the site of the stenosis. The apposition of the stent to the vessel wall was imaged by high-resolution radiography. RESULTS: Analysis of variance showed significant differences of radial force between the tested stents (P <.001). The ML-Tristar and ML-Ultra stents had the highest radial force with maximum mean values of 687 cN and 846 cN at a stenosis of 70% in the model with the long stenosis. The radial force of the S670 stent was the lowest whereas the MAC stents showed an intermediate radial force. Radial force of the ML-Ultra stent was as much as 3.8 times higher than the force of the S670 stent (P <.001). Fifty percent of the ML-Tristar and ML-Ultra stents did not expand sufficiently to touch the vessel surface at the outer curvature. With an inflation pressure of 17 atm, complete apposition of these stents was achieved. The highest number of apposition irregularities was found in the S670 group (13 of 14 stents), whereas the MAC stents revealed the lowest number of irregular appositions (three of 14 stents). A significant correlation was found between the number of interconnecting struts and the number of irregular apposition events (P <.01). CONCLUSIONS: This model allows an accurate in vitro evaluation of different stent parameters, such as apposition to the vessel wall and radial force. None of the investigated stents showed optimal results with respect to both parameters. The apposition behavior was significantly influenced by the architecture of the stents.  相似文献   
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