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991.
Volumetric modulated arc therapy (VMAT) is a novel radiation technique, which can achieve highly conformal dose distributions with improved target volume coverage and sparing of normal tissues compared with conventional radiotherapy techniques. VMAT also has the potential to offer additional advantages, such as reduced treatment delivery time compared with conventional static field intensity modulated radiotherapy (IMRT). The clinical worldwide use of VMAT is increasing significantly. Currently the majority of published data on VMAT are limited to planning and feasibility studies, although there is emerging clinical outcome data in several tumour sites. This article aims to discuss the current use of VMAT techniques in practice and review the available data from planning and clinical outcome studies in various tumour sites including prostate, pelvis (lower gastrointestinal, gynaecological), head and neck, thoracic, central nervous system, breast and other tumour sites.  相似文献   
992.

Introduction

In the previous study we have demonstrated that in healthy subjects significant changes in coronal and transverse plane mechanics can be produced by the application of a neutral patella taping technique and a patellar brace. Recently it has also been identified that patients with patellofemoral pain syndrome (PFPS) display alterations in gait in the coronal and transverse planes.

Objective

This study investigated the effect of patellar bracing and taping on the three-dimensional mechanics of the knee of patellofemoral pain patients during a step descent task.

Method

Thirteen patients diagnosed with patellofemoral pain syndrome performed a slow step descent. This was conducted under three randomized conditions: (a) no intervention, (b) neutral patella taping, (c) patellofemoral bracing. A 20 cm step was constructed to accommodate an AMTI force platform. Kinematic data were collected using a ten camera infra-red Oqus motion analysis system. Reflective markers were placed on the foot, shank and thigh using the Calibrated Anatomical System Technique (CAST).

Results

The coronal plane knee range of motion was significantly reduced with taping (P = 0.031) and bracing (P = 0.005). The transverse plane showed a significant reduction in the knee range of motion with the brace compared to taping (P = 0.032) and no treatment (P = 0.046).

Conclusion

Patients suffering from patellofemoral pain syndrome demonstrated improved coronal plane and torsional control of the knee during slow step descent following the application of bracing and taping. This study further reinforces the view that coronal and transverse plane mechanics should not be overlooked when studying patellofemoral pain.  相似文献   
993.
994.
Background: There are case reports and small series in the literature relating to the use of medicinal leeches by plastic surgeons; however, larger series from individual units are rare. The aim of this article is to present a comprehensive 4‐year case series of the use of medicinal leeches, discuss the current evidence regarding indications, risks, and benefits and highlight the recent updates regarding leech speciation. Methods: Patients prescribed leeches in a 4‐year period (July 2004–2008) were collated from hospital pharmacy records (N = 35). The number of leeches used, demographic, clinical, and microbiological details were retrospectively analyzed. Results: Thirty‐five patients were treated with leeches. The age range was 2 to 98 years (mean = 49.3). Leeches were most commonly used for venous congestion in pedicled flaps and replantations. Blood transfusions were necessary in 12 cases (34%) [mean = 2.8 units, range 2–5 units]. Our infection rate was 20% (7/35) including five infections with Aeromonas spp. (14.2%). The proportion of patients becoming infected after leech therapy was significantly greater in the group of patients that did not receive prophylactic antibiotic treatment (Fisher's Exact test P = 0.0005). In total, 14 cases (40%) were salvaged in entirety, in 7 cases 80% or more, in 2 cases 50 to 79%, and in 1 case less than 50% of the tissues were salvaged. In 11 cases (31%), the tissues were totally lost. Conclusion: Our study highlights both the benefits and the risks to patients in selected clinical situations and also the potential risks. The routine use of antibiotic prophylaxis is supported. In view of the emerging evidence that Hirudo verbana are now used as standard leech therapy, and the primary pathogen is Aeromonas veronii, until a large prospective multicenter study is published, large series of patients treated with leeches should be reported. © 2011 Wiley‐Liss, Inc. Microsurgery, 2011.  相似文献   
995.
In June 2010, the European Board of Anaesthesiology (EBA) of the European Union of Medical Specialists (UEMS) and the European Society of Anaesthesiology (ESA) signed the Helsinki Declaration for Patient Safety in Anaesthesiology at the Euroanaesthesia meeting in Helsinki. The document had been jointly prepared by these two principal anaesthesiology organisations in Europe who pledged to improve the safety of patients being cared for by anaesthesiologists working in the medical fields of perioperative care, intensive care medicine, emergency medicine and pain medicine. The declaration stated their current heads of agreement on patient safety and listed a number of principle requirements as thought necessary for anaesthesiologists, anaesthesiology departments and institutions to introduce to improve patient safety. Good words are only as good as their implementation and this article explains the rationale behind them and expands the recommendations practically so anaesthesiologists caring for patients everywhere can follow the Helsinki Declaration and put the words into practice.  相似文献   
996.
A 58-year-old female presented with symptoms mimicking infective endocarditis and was diagnosed with a right ventricular metastasis from a transitional cell carcinoma (TCC) of the left renal pelvis. The patient was treated with concurrent removal of the cardiac tumour and radical left nephrectomy followed by adjuvant gemcitabine-cisplatin chemotherapy. To our knowledge, this is the 14th report of cardiac metastases from TCC and the only case where one-stage surgical management of primary and cardiac metastases from TCC has been successfully completed.  相似文献   
997.
Studies with animal seizure models have indicated that changes in temporal and spatial expression of voltage-gated sodium channels may be important in the pathology of epilepsy. Here, by using in situ hybridisation with previously characterised subtype-selective oligonucleotide probes [Whitaker et al. (2000) J. Comp. Neurol. 422, 123-139], we have compared the cellular expression of all four brain alpha-subunit sodium channel mRNAs in "normal" and epileptic hippocampi from humans. Neuronal cell loss was observed in all regions of the hippocampus of diseased patients, indicating that sclerosis had occurred. Losses of up to 40% compared to post-mortem controls were observed which were statistically significant in all regions studied (dentate gyrus, hilus, and CA1-3).To assess mRNA levels of the different alpha-subtypes in specific subregions, control and diseased tissue sections were hybridised to subtype-specific probes. To quantify any changes in expression while allowing for cell loss, the sections were processed for liquid emulsion autoradiography and grain counts were performed on populations of individual neurones in different subregions. No significant differences were found in the expression of type I and VI mRNAs. In contrast, a significant down-regulation of type II mRNA was observed in the epileptic tissue in the remaining pyramidal cells of CA3 (71+/-7% of control, P<0.01), CA2 (81+/-8% of control, P<0.05) and CA1 (72+/-6% of control, P<0.05) compared with control tissue. Additionally, a significant up-regulation in type III mRNA in epileptic CA4 pyramidal cells (145+/-7% of control, P<0.05) was observed.It is not clear whether these changes play a causal role in human epilepsy or whether they are secondary to seizures or drug treatment; further studies are necessary to investigate these alternatives. However, it is likely that such changes would affect the intrinsic excitability of hippocampal neurones.  相似文献   
998.
999.
Although it is often assumed that awareness decreases as dementia severity increases, there is limited evidence regarding changes in awareness over time. We examined awareness in 101 individuals with early-stage dementia (PwD) and their carers; 66 were reassessed after 12 months and 51 were seen again at 20 months. Awareness was assessed in relation to memory, everyday activities, and socio-emotional functioning using discrepancies between PwD and carer ratings on parallel questionnaires. PwD completed neuropsychological tests and measures of mood and quality of life. Carers completed measures of mood and stress. At initial assessment, discrepancies were greatest for activities of daily living, moderate for memory, and least pronounced for socio-emotional functioning. Discrepancy scores did not change over time. PwD self-ratings indicated perceived poorer functioning in everyday activities over time, but no change for memory and socio-emotional functioning. Carer ratings indicated perceived decline in everyday activities and socio-emotional functioning, but no change for memory. PwD declined in neuropsychological functioning, but self-ratings of depression, anxiety, and quality of life remained stable over time. Carer mood and stress levels also remained stable. At least in the earlier stages of dementia, it should not be assumed that awareness will inevitably decrease as dementia progresses.  相似文献   
1000.
Objectives: In early-stage dementia, awareness at the meta-representational level involving a person's appraisal of his/her own condition and its implications has usually been assessed by interview, but contextual factors may influence responding. We examined the utility of an indirect, vignette-based method of eliciting awareness.

Method: Three vignettes describing early-stage dementia, established dementia and healthy ageing were used to elicit views of the problem and the kinds of advice that might be helpful for the characters depicted. Responses were obtained from 91 people with early-stage Alzheimer's, vascular or mixed dementia, 87 carers and 80 older controls. For the participants with dementia, awareness was assessed in separate in-depth interviews and rated on a five-point scale for comparison purposes.

Results: Participants with dementia were often able to correctly identify the problems described in the vignettes, although scoring lower than carers or controls. Participants with dementia were also able to offer advice for those depicted, although to a lesser extent than carers or controls. Ability to offer advice was greater where MMSE scores were higher. For participants with dementia, vignette scores were moderately correlated with ratings derived from interviews, and those showing limited or no awareness offered fewer items of advice than those showing some or good awareness. In addition, 29% of participants with dementia spontaneously pointed out similarities between their own condition and that of the person depicted.

Conclusions: The vignette method may be useful where resources preclude the use of in-depth interviews, and may supplement in-depth interviews as part of a multi-dimensional assessment of awareness.  相似文献   

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