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We present the case of a 19-year-old individual presenting to an orthopaedic outpatient clinic several months following a dashboard knee injury during a road traffic accident with intermittent mechanical symptoms. Despite unremarkable examination findings and normal magnetic resonance imaging, the patient was identified subsequently as having an intra-articular plastic foreign body consistent with a piece of dashboard on arthroscopic knee assessment, the retrieval of which resulted in a complete resolution of symptoms.  相似文献   
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OBJECTIVES: Cartilage is avascular and relatively homogeneous, making it an attractive tissue for in vitro histogenesis and surgical use in patients. We developed novel platform technologies in order to define the requirements for optimal in vitro chondrogenesis by isolated cells. In this series of studies, we tested alternatives to fetal bovine serum (FBS) and the effects of growth factors on formation of cartilage in 3D porous collagen sponges. DESIGN: We used porous collagen sponges to assess the effects of serum substitutes and exogenous TGF-beta1 and IL-1alpha on chondrocytes (bovine articular chondrocytes, bACs) and on chondroinduced human dermal fibroblasts (hDFs). We determined the effects of low concentrations of FBS and two serum substitutes, Nutridoma and ITS(+3), on cellularity and matrix production. After culture for intervals, sponges were harvested for histological and biochemical measurement of cartilage-specific chondroitin 4-sulfate proteoglycan (C 4-S PG). RESULTS: Cultured bACs showed equivalent growth in Nutridoma (1%) and 10% FBS. Both TGF-beta1 and IL-1alpha significantly stimulated accumulation of C 4-S PG by bACs in 3D porous collagen sponges. Many endogenous growth factors were upregulated in hDFs cultured with chondroinductive DBP. Addition of TGF-beta1 and IL-1alpha for 11 days significantly stimulated accumulation of C 4-S PG by hDFs cultured in DMEM with 1% Nutridoma. CONCLUSION: Porous collagen sponges are supportive of chondrogenesis and of chondroinduction by DBP. Optimization of serum-free culture conditions, including growth factors, matrix components, and mechanical stimuli will expedite translation to wider clinical applications. Use of autogenous dermal fibroblasts pre-cultured with DBP and induced to chondrocytes offers an alternative to autogenous chondrocytes.  相似文献   
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Benign cardiac tumors are rare; they can present with nonspecific symptoms and represent a diagnostic challenge to the clinician. We describe an interesting case of a 26-year-old female who presented with a 6-month history of cough, breathlessness, palpitations, dizziness, and fever. Despite repeated clinical reviews in the community, diagnosis of cardiac tumor was not made until she developed decompensated cardiac failure with bilateral pleural effusions and pulmonary edema. Echocardiogram revealed an enormous left atrial mass that extended one-third into left ventricle during systole. The patient underwent successful surgical resection with histological confirmation of a benign atrial myxoma.  相似文献   
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BACKGROUND: Chest pain is the second most common presenting complaint seen in the emergency department. Following evaluation in the emergency department, many of these patients are discharged with a diagnosis of nonspecific chest pain. Our hypothesis is that this group of patients has a high prevalence of ischaemic heart disease. METHODS: This was a prospective follow-up study of mortality in 786 patients who presented to an emergency department in the UK with an episode of nontraumatic chest pain and were discharged without further inpatient assessment. Observed mortality was compared with expected mortality in age-matched and sex-matched local population. RESULTS: The observed mortality of the study group was consistently higher than expected throughout the study period. The 5-year mortality rates for men and women under the age of 65 years were more than double the expected rates for the local population [relative risk of 2.1 (95% confidence interval: 1.4-2.8) and 2.6 (1.4-3.8), respectively]. This increase was less marked in male and female patients aged 65 years or more [relative risk of 1.2 (0.9-1.5) and 1.5 (1.2-1.8), respectively]. Ischaemic heart disease accounted for almost 50% of male deaths in the study group. This compared with an expected rate of less than 30% of male deaths in the local population. An excess of cardiac deaths was not seen in women. INTERPRETATION: Patients discharged from the emergency department following an episode of acute chest pain have significantly reduced 5-year survival. We conclude that further evaluation of this group to establish the prevalence of risk factors is important to support the strategic implementation of appropriate prevention programmes.  相似文献   
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Clinical & Experimental Metastasis - Invasive breast cancer tends to metastasize to lymph nodes and systemic sites. The management of metastasis has evolved by focusing on controlling the...  相似文献   
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