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A comprehensive study of femoral heads of patients and cadavers with osteoarthritis, rheumatoid arthritis, osteonecrosis, and calcium pyrophosphate dihydrate deposition disease allows insight into the radiographic and pathologic appearance of subchondral radiolucencies in these disorders. The term geode, rather than cyst or pseudocyst, may be a more appropriate decription of these lesions. In osteoarthritis, goedes occur on the pressure segment of the femoral head in association with loss of articular space; in rheumatoid arthritis, they are initially noted at the chondro-osseous junction and subsequently involve the entire femoral head. In osteonecrosis, geodes appear in the necrotic segment of the femoral head. In calcium pyrophosphate deposition disease, geodes resemble those in osteoarthritis but are larger, more numerous, and more widespread.  相似文献   
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INTRODUCTION: N-Methyl,N-propargyphenylethylamine (MPPE) is a novel analog of (-)-deprenyl, a drug prescribed for Parkinson's disease and shown to have neuroprotective and neurorescue properties in a wide variety of in vitro and in vivo models. MPPE is also neuroprotective, but has the advantage over (-)-deprenyl of not being metabolized to amphetamine or N-methylamphetamine. METHOD: In this paper, extractive derivatization with pentafluorobenzenesulfonyl chloride (PFBSC) followed by electron-capture gas chromatography was utilized to study the metabolism of MPPE. RESULTS: The procedure is rapid and reproducible, giving derivatives with excellent chromatographic properties. Using this procedure, it has now been shown that beta-phenylethylamine (PEA), N-methylphenylethylamine (N-methylPEA) and N-propargylphenylethylamine (N-propargylPEA) are formed from MPPE during incubation of this drug with human liver microsomes. Levels of all three metabolites were shown to increase with increasing time of incubation with the microsomes. DISCUSSION: Extractive derivatization with PFBSC followed by electron-capture gas chromatography represents an efficient means of separating and quantitating the metabolites of MPPE, a novel neuroprotective agent.  相似文献   
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The treatment of chronic wounds represents a major cost to society and has a profound effect on the participant's quality of life. Chronic wounds may have an increased bacterial burden that can impair healing without all the clinical signs of infection. Silver dressings may provide an alternative topical method to control bacterial burden. The primary aim of this study was to evaluate the clinical improvement in chronic wounds through the effect on wound size, maceration, resolution of surface slough and conversion to healthy granulation during a 4-week application of the silver-containing Hydrofiber dressing. This was a single centre, open-label case series study which included a total of 30 evaluable participants: four with diabetic neuropathic foot ulcers, 13 venous stasis ulcers, four pressure ulcers and nine miscellaneous wounds that did not fit any of the previous categories. All participants had adequate vascular supply, indicating the potential to heal. The wounds were stalled or had the signs and symptoms consistent with critical colonisation. The underlying cause of the ulceration was identified and corrected, or the symptoms and signs were treated. This was followed by the application of silver-containing Hydrofiber dressings for a period of 4 weeks. The majority of wounds treated decreased in size (70%) with decreased exudate, decreased purulence and resolution of surface slough (75%). There was an increased quality and quantity of healthy granulation tissue. Unlike some silver dressings, the Hydrofiber and silver combination dressing was unlikely to cause burning and stinging on application. Peri-wound maceration was present in 54% of participants at baseline, and 85% of these resolved with this dressing. A desloughing action was seen in those patients with pre-existing slough at baseline and its removal will lower the bacterial burden of the wound.  相似文献   
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Vascular rings—presentation,investigation and outcome   总被引:1,自引:1,他引:0  
Our aim was to determine the presentation of patients with vascular rings and evaluate the effectiveness of investigations. Surgical outcomes and respiratory sequelae were also examined. The design was a retrospective case note study over a 13-year period set in a tertiary childrens hospital. Children below the age of 16 years presenting with a vascular ring to the Royal Hospital for Sick Children, Glasgow were studied. Demographic data at presentation, including symptoms, were recorded. The ability of diagnostic investigations to identify the presence of a vascular ring was evaluated. Surgical outcomes were determined by measuring surgical complications and mortality. Respiratory sequelae were recorded by the presence of persistent symptoms or the need for tracheostomy or long-term ventilation following surgery. A total of 24 patients were identified with a median age at presentation of 4.5 months. Stridor was the commonest presenting symptom (14/24). Angiography, chest CT scanning and MRI were the most accurate imaging modalities (accurate in 100% of cases used). Chest X-ray films and echocardiography had the lowest detection rates. Surgical complications (4/24) and mortality (1/24) were low. A substantial number of patients available to follow-up (7/20) were still experiencing stridor 3 months post-operatively. Conclusion:Vascular rings are rare, however, often present with common symptoms. Most children present in early infancy, but a minority presents much later. The investigation of choice is a barium swallow followed by high-resolution computed tomography. Surgery is safe although a number of patients will have persisting symptoms.  相似文献   
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BACKGROUND AND AIMS: UK consultants have reported working long hours, increased stress and reduced morale. This study set out to elicit consultants' views on flexible working and to gather data on consultants' workloads, remuneration, job satisfaction and retirement plans. As such it is the first comprehensive study of consultants in NHS Scotland. METHODS: The Information and Statistics Division of the Scottish Executive Health Dept provided a list of consultants working in NHS Scotland Focus groups and interviews informed the design of a postal self-completion, questionnaire. RESULTS: The response ratewas 61%. Almost two-thirds (65%) of respondents felt their workloads were unreasonable and unsustainable and 67% were unable to provide their desired standards of patient care. Two-thirds (67%) did not normally take meal breaks, 63% had insufficient time for outside interests, whilst 44% felt their health was being adversely affected Many (84%) believed that some of their work could be delegated to someone less qualified but 79% agreed that there were insufficient staff to make this possible. The average planned retirement age was 60 years, with 23% describing their plans as definite and 70% as quite or very likely. When asked what might induce them to postpone retirement, 50% cited reduced workload/work intensity. CONCLUSIONS: In 2003, a majority of consultants in the UK voted in favour of the new consultant contract. This will improve consultant pay and introduce a standard 40-hour working week, including worked on-call. This should address tow of the main areas of consultant dissatisfaction in NHS Scotland. However, staff shortages will require to be addressed if the contract is to be successfully implemented.  相似文献   
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The gastrointestinal pharmacology of cannabinoids: an update   总被引:1,自引:0,他引:1  
Recent work in the field of gastrointestinal pharmacology of cannabinoids has focused on enteric endocannabinoid and endovanilloid systems and their modulation in pathophysiological conditions. CB(1) receptor immunoreactivity was detected on enteric cholinergic neurones and vasoactive intestinal peptide-containing submucosal ganglion cells, on discrete nuclei of the dorsovagal complex (involved in emesis) and on central and peripheral vagal terminals, thus controlling gastroesophageal reflux and gastrointestinal motility. CB(1) receptor activation by endocannabinoids inhibited induced fluid secretion and inflammation in animal models and reduced proliferation of cultured colorectal cancer cells. Endocannabinoids also activate cannabinoid CB(2) and vanilloid VR1 receptors in certain inflammatory states. Thus endocannabinoid metabolism could provide a useful therapeutic target for many gastrointestinal disorders.  相似文献   
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