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81.
SUMMARY

The National Health Service (NHS) Cancer Plan published in 2000 has a short-term focus on the most pressing problems of improving survival rates and replacing equipment. It also mentioned as a target 'improved quality of life for those affected by cancer'. Continuity of care for longer-term care programmes was seen predominantly in terms of palliative care. Recent National Institute for Clinical Excellence (NICE) reports may have reinforced this approach by focussing on the clinical and cost effectiveness of chemotherapy for late-stage cancer. The impact on local decision-makers has been that drug funds have been prioritised for use on survival-enhancing interventions, with few resources left for short and longer-term supportive care targeted primarily on improving quality of life. Within supportive care, resources are particularly limited for funding treatments such as erythropoietin for the management of cancer-related anaemia, a common and very debilitating side-effect of intensive therapy. The need for a re-focusing on supportive care is associated with cancer becoming, in many instances, a longer-term illness. The prevalence of

cancer is rising markedly due to increased survival rates. However, this creates a new challenge of reducing disability and improving quality of life. In surveys, patients have rated fatigue associated with anaemia as one of the most debilitating effects of their cancer and its treatment with chemotherapy. This paper reviews the evidence demonstrating the quality of life benefits of erythropoietin, and then considers the policy constraints that have limited the adoption of this treatment within the NHS. Through co-ordinated planning there are opportunities for cancer networks and primary care trusts (PCTs) working with cancer centres to develop more support in ways which are feasible and fundable. The case is argued that PCTs and cancer networks, in implementing the Cancer Plan locally, need to integrate short- and longer-term supportive care into their cancer service development plans, and recognise the importance of anaemia management as an integral part of this. Lessons can be learnt from UK renal services where anaemia management with erythropoietin is standard practice.  相似文献   
82.
The purpose of the study was to contrast first panic attacks (PAs) of patients with panic disorder (PD) with vs. without agoraphobia and to explore differences between first PAs leading to the development of PD and those that remain isolated. Data were drawn from a community survey (N = 2259 including 88 isolated PAs and 75 PD cases). An additional sample of 234 PD patients was recruited in a clinical setting. A standardized interview assessed the symptoms of the first PA, context of its occurrence and subsequent coping attempts. Persons who developed PD reported more severe first PAs, more medical service utilization and exposure-limiting coping attempts than those with isolated PAs. The context of the first PA did not differ between PD and isolated PAs. PD with agoraphobia was specifically associated with greater symptom severity and occurrence of first attacks in public. Future research should validate these findings using a longitudinal approach.  相似文献   
83.
Understanding the behaviour of implantable medical devices is of obvious importance. The potential for failure of a medical device can often be associated with issues related to cyclic loading of the device, and material fatigue. Detailed finite element simulations to evaluate the fatigue of stents allow the engineer to assess potential failures. The engineer can then use the analysis results to modify the design and prevent failure, without making and testing numerous physical devices. Complete understanding of the mechanical behaviour of a stent provided by finite element analysis has the benefits of facilitating effective design, helping to reduce time to market and minimising the potential for unwanted failures.  相似文献   
84.
目的总结糖尿病夏科足的临床特点,提高临床医师对于本病的认识。方法回顾性分析11例2型糖尿病夏科足患者的临床特点。结果 11例患者中,男7例,女4例;平均年龄(60±11)岁;平均糖尿病病程16年;全部合并神经病变而无下肢血管病变;单侧足病变10例,双足病变1例;3例发病前有明确的外伤史。影像学表现为足部骨质破坏7例,关节间隙变窄6例,软组织肿胀3例,关节半脱位2例,关节融合2例,碎骨1例。11例患者一入院均遵医嘱限制活动。对足溃疡给予积极清创,换药。根据细菌培养及药敏试验结果选用抗生素治疗。10例合并足溃疡病例中,1例截趾后愈合,3例愈合,5例好转,1例自动出院后失访。3例出院后有足溃疡的复发。结论早期识别并给予制动等措施有助于足溃疡愈合和减缓夏科足畸形的发展。  相似文献   
85.
We report the case of a 34-year-old woman with severe post-infectious gastroparesis who was transferred from an outside medical facility for a second opinion regarding management.This patient had no prior history of gastrointestinal symptoms.However,in the aftermath of a viral illness,she developed two months of intractable nausea,vomiting,and oral intake intolerance that resulted in numerous hospitalizations for dehydration and electrolyte disturbances.A solid-phase gastric emptying scan had confirmed delayed emptying,confirming gastroparesis.Unfortunately,conventional pro-kinetic agents and numerous anti-emetic drugs provided little or no relief of the patient’s symptoms.At our institution,the patient experienced a cessation of vomiting,reported a significant reduction in nausea,and toler-ated oral intake shortly after taking mirtazapine.Based on mirtazapine’s primary action as a serotonin(5-HT)1a receptor agonist,we infer that this receptor system mediated the clinical improvement through a combination of peripheral and central neural mechanisms.This report highlights the potential utility of 5-HT1a agonists in the management of nausea and vomiting.We conclude that mirtazapine may be effective in treating symptoms associated with non-diabetic gastroparesis that are refractory to conventional therapies.  相似文献   
86.
Neck-stem modularity gained recent popularity in hip arthroplasty for clinical advantages, and few complications have been reported. We describe an unusual two-stage failure of the bimodular neck of a cementless forged titanium alloy stem implanted 12 years before. The retrieved neck was forwarded to the manufacturer for metallurgic evaluation and failure analysis. Lengthening and bending of the superolateral aspect of the neck and double depression of the medial part prove that the prosthetic neck underwent a medial displacement and a varus rotation. The crack initiated from the superolateral corner of the fracture section, and the neck probably underwent two subsequent unstable configurations. The first horizontal part of the fracture occurred in the external surface as a result of physiological load carried on abnormal conditions of frictions. Due to increased oscillations, the end of the fracture section knocked against the inner aspect of the proximal hole of the stem, preventing further valgus displacement of the neck, which was moved forward. Consequently, the neck achieved a second unstable configuration, and the fracture propagated in the weaker direction creating a bent track. Finally, the neck broke unexpectedly as a result of the traumatic event. An incorrect placement into the femoral component during surgery was the initiation of the failure of the bimodular neck. The transitory but repeated interface motion between the neck and the stem induced a local surface irregularity acting as a starting point for crack propagation of fatigue fracture. Final failure followed a direct trauma.  相似文献   
87.
88.
Gestational trophoblastic disease (GTD) is a group of tumours caused by the hyperproliferation of trophoblast cells and is noted for its overproduction of hCG. Among its manifestations, there may be hyperthyroidism, due to the stimulating activity of hCG on TSH receptors. In most cases it is only a biochemical hyperthyroidism, with its presentation as symptomatic hyperthyroidism being much less frequent. We report the case of a patient with GTD, who at diagnosis presented with symptomatic hyperthyroidism. Treatment included surgical evacuation of the hydatidiform mole, as well as a beta-blocker and antithyroid drug treatment to relieve the symptoms.  相似文献   
89.
《Dental materials》2022,38(1):204-213
ObjectiveTo investigate the fatigue behavior of restored teeth, in particular the mechanisms of longitudinal dentinal cracking under cyclic mechanical loading, using finite element analysis (FEA) and the stress-life (S-N) approach.MethodsTen root-filled premolars restored with resin composites were subjected to step-stress cyclic loading to produce longitudinal cracks. Fracture loads and number of cycles completed at each load level were recorded. FEA was used to predict the stress amplitude of each component under the global cyclic load. Both intact and debonded conditions were considered for the dentin-composite interface in the FEA. The predicted stress concentrations were compared with the fracture patterns to help elucidate the failure mechanisms. The S-N approach was further used to predict the lifetimes of the different components in the restored teeth. Cumulative fatigue damage was represented by the sum of the fractions of life spent under the different stress amplitudes.ResultsLongitudinal cracks were seen in ~50% of the samples with a mean fracture load of 770 ± 45 N and a mean number of cycles to failure of 32,297 ± 12,624. The longitudinal dentinal cracks seemed to start near the line angle of the cavity, and propagated longitudinally towards the root. The sum of fractions of life spent for the dentin-composite interface exceeded 1 after ~7000 cycles when that for dentin was much lower than 1, indicating that interfacial debonding would occur prior to dentin fracture. This was supported by micro-CT images showing widened interfacial space in the cracked samples. In the debonded tooth, FEA showed dentinal stress concentrations at the gingival wall of the cavity, which coincided with the longitudinal cracks found in the cyclic loading test. The sum of fractions of life spent for dentin was close to 1 at ~30,000 cycles, similar to the experimental value.SignificanceDebonding of the dentin-composite interface may occur prior to longitudinal cracking of dentin in root-filled teeth under cyclic loading. The approximate time of occurrence for these events could be estimated using fatigue analysis with stresses provided by FEA. This methodology can therefore be used to evaluate the longevity of restoration designs for root-filled teeth.  相似文献   
90.
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