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51.
Piotr Reorowicz Damian Obidowski Przemyslaw Klosinski Wojciech Szubert Ludomir Stefanczyk Krzysztof Jozwik 《Journal of biomechanics》2014
The Cerebral Circle Region, also known as the Circle of Willis (CoW), is a loop of arteries that form arterial connections between supply arteries to distribute blood throughout the cerebral mass. Among the population, only 25% to 50% have a complete system of arteries forming the CoW. 3D time-varying simulations for three different patient-specific artery anatomies of CoW were performed in order to gain a better insight into the phenomena existing in the cerebral blood flow. The models reconstructed on the basis of computer tomography images start from the aorta and include the largest arteries that supply the CoW and the arteries of CoW. Velocity values measured during the ultrasound examination have been compared with the results of simulations. It is shown that the flow in the right anterior artery in some cases may be supplied from the left internal carotid artery via the anterior communicating artery. The investigations conducted show that the computational fluid dynamic tool, which provides high resolution in both time and space domains, can be used to support physicians in diagnosing patients of different ages and various anatomical arterial structures. 相似文献
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Dental rehabilitation of a completely edentulous geriatric patient has always been a challenge to the clinician, especially in treating those with higher expectations and demands. Treatment duration and the amount of residual alveolar bone available are often important considerations when planning for dental implant-based fixed treatment for these patients. With the introduction of zygomatic implants, a graftless alternative solution has emerged for deficient maxillary bone with provision for immediate loading. This article describes the treatment of a completely edentulous elderly patient using zygomatic implants in conjunction with conventional implants. The implants were immediately loaded using a definitive acrylic resin fixed denture reinforced with a cast metal framework, to provide function and aesthetics. 相似文献
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OBJECTIVE: Periodontoid pseudotumours are lesions of presumed degenerative aetiology which typically occur in elderly patients with cervical myelopathy. The clinical and radiological differential diagnosis includes neoplastic and inflammatory lesions, and the exclusion of such lesions may be of value in the intra-operative management of the patient. This audit aimed to examine the value of intra-operative smear cytology in the management of this condition. METHODS: The intra-operative smear cytological features of four cases of periodontoid pseudotumour were reviewed. RESULTS: In each case the intra-operative cytological interpretation was in keeping with a non-neoplastic and non-inflammatory process. CONCLUSION: These results suggest that intra-operative smear cytology can provide information on the value in the intra-operative management of patients with this lesion. 相似文献
56.
Assisting suicide is legal in Switzerland if it is offered without selfish motive to a person with decision‐making capacity. Although the ‘Swiss model’ for suicide assistance has been extensively described in the literature, the formally and informally protected liberties and claims of assistors and recipients of suicide assistance in Switzerland are incompletely captured in the literature. In this article, we describe the package of rights involved in the ‘Swiss model’ using the framework of Hohfeldian rights as modified by Wenar. After outlining this framework, we dissect the rights involved in suicide assistance in Switzerland, and compare it with the situation in England and Germany. Based on this approach, we conclude that in Switzerland, claim rights exist for those requesting suicide assistance, and for those who are considering providing such assistance, even though no entitlements exist toward suicide assistance. We then describe the implementation of the ‘Swiss model’ and difficulties arising within it. Clarifying these issues is important to understand the Swiss situation, to evaluate what features of it may or may not be worth correcting or emulating, and to understand how it can impact requests for suicide assistance in other countries due to ‘suicide tourism’. It is also important to understand exactly what sets Switzerland apart from other countries with different legislations regarding suicide assistance. 相似文献
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G. De Santis M. De Beule P. Segers P. Verdonck B. Verhegghe 《Computer methods in biomechanics and biomedical engineering》2013,16(9):797-802
Measuring the blood flow is still limited by current imaging technologies and is generally overcome using computational fluid dynamics (CFD) which, because of the complex geometry of blood vessels, has widely relied on tetrahedral meshes. Hexahedral meshes offer more accurate results with lower-density meshes and faster computation as compared to tetrahedral meshes, but their use is limited by the far more complex mesh generation. We present a robust methodology for conformal and structured hexahedral mesh generation – applicable to complex arterial geometries as bifurcating vessels – starting from triangulated surfaces. Cutting planes are used to slice the lumen surface and to construct longitudinal Bezier splines. Afterwards, an isoparametric transformation is used to map a parametrically defined quadrilateral surface mesh into the vessel volume, resulting in stacks of sections which can then be used for sweeping. Being robust and open source based, this methodology may improve the current standard in patient-specific mesh generation and enhance the reliability of CFD to patient-specific haemodynamics. 相似文献
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Sit to stand (STS) transfers form a challenging type of motion, in particular for geriatric patients. Physical assistive devices that are built to enhance the mobility of this class of patients therefore must especially be able to support STS transfers. This paper presents a method to predict geriatric STS movements and compute the best possible actions by external devices to support these movements. We treat three types of active devices that act on different parts of the patient’s body and provide different levels of support. Our approach is based on the solution of optimal control problems for a whole-body multi-phase model of humans standing up from sitting to upright position. Computations are performed for percentiles 20/50/80 of male and female geriatric population. The actions of the external devices are simulated by external forces at moving contact points, which are all determined by the optimization, simultaneously with the expected movements and joint torques of the patients. The results serve as inputs for design optimizations of the different device types. 相似文献
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Marcelo Coelho Goiato Humberto Genneri Filho Daniela Micheline dos Santos Valentim Adelino Ricardo Barão Amilcar Chagas Freitas Júnior 《Gerodontology》2011,28(3):197-204
Gerodontology 2010; 00; doi: 10.1111/j.1741‐2358.2010.00368.x Insertion and follow‐up of complete dentures: a literature review Objective: The aim of this study was to present the importance of clinical procedures related to insertion and follow‐up of complete dentures in elderly patients. Materials and Methods: The success of rehabilitation with complete dentures results from the accuracy of clinical and laboratorial procedures that makes the denture insertion an important step of treatment. Conclusion: The follow‐up and professional maintenance of function and hygiene facilitates long‐term efficiency. 相似文献
60.
《Reports of Practical Oncology and Radiotherapy》2014,19(6):428-432
AimTo investigate incidence of toxicity and related hospitalization among patients treated at our institute by a short course of palliative cranial radiotherapy against a longer, widely established schedule.BackgroundShorter schedule palliative cranial radiotherapy is more convenient for patients and reduce waiting times. Although many studies have established safety of short schedules, the need for hospitalization due to acute treatment toxicity remains under-explored. Hospital admissions are an economic burden both for the patient and healthcare system in a limited resource setting. Delivery of treatment on an outpatient basis and within shorter times is preferred by patients, caregivers and healthcare staff.Materials and methodsThis was a prospective study on 68 patients treated with palliative whole brain radiotherapy between November 2010 and October 2012. One group received 20 Gy in 5 fractions over 1 week and the other group, 30 Gy in 10 fractions over 2 weeks. Treatment toxicity due to cranial radiotherapy was assessed as per RTOG acute and late toxicity criteria. Need for hospitalization owing to acute toxicity was also noted. Significant differences in the study parameters between the two groups were calculated by Fisher's t-test.ResultsRequirement for hospital stay due to acute toxicity was not significantly different between the two groups. Patients in both groups experienced similar toxicity both during and after treatment.ConclusionsThe shorter course entailed no significant increase in toxicity related admissions, suitable for limited resource settings where patient transport is difficult, there are financial constraints, and the healthcare system is overburdened. 相似文献