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Cardiovascular and noncardiovascular conditions are commonly encountered in the emergency department. While the majority of patients have underlying cardiovascular aetiologies, such as acute myocardial infarction, congestive heart failure, aortic dissection and pulmonary embolism, a small subset of patients have underlying noncardiovascular conditions, although they present with similar symptoms of chest pain, dyspnoea, cough, haemoptysis and haematemesis. This article aims to describe the imaging findings in common noncardiovascular conditions of the chest that are frequently encountered in the emergency department, with a review of the existing literature.  相似文献   
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Introduction Coronary artery bypass grafting (CABG) associated with Endarterectomy is a high risk procedure. After the first report of coronary endarterectomy by Bailey et al in 1951, the preference for this surgical procedure was decreased due to increased morbidity and mortality In patients with total or subtotal large coronary artery obstructions in which there is no possibility to receive a conduit as graft for myocardial revascularisation, endarterectomy remains the procedure of choice. This study was designed to study early and midterm results of off pump coronary artery endarterectomy. Methods Of 172 Consecutive Off Pump CABG done at our institution from Jan 2003 to July 2005, 22 patients underwent supplementary coronary endarterectomy. 16 patients had chronic stable angina 4 had unstable angina two required emergency CABG with endarterectomy following perioperative infarction. The mean ejection fraction was 29.2±4.3 and all of the patients were in New York Heart Association (NYHA) III or IV. All patients were planned for complete total arterial revascularisation using Left Internal Mammary Artery (LIMA). Right Internal Mammary Artery (RIMA), Radial composite “Y” graft, Two patients operated for periop infarct received vein graft. In 16 patients closed endarterectomy was done in five patients double endarterectomy in single vessel was done to chase the plaque distally, in one patient open left anterior descending (LAD) endarterectomy with vein patch reconstruction was performed. Results There were no deaths. None of the procedures were converted to on pump operation. All endarterectomies and bypasses were performed on Beating Heart, all patients were completely revascularised. Peri operative cardiac enzymes studied showed no significant rise in the Creatinine Phoshpokinase (CPK)-Creatinine Phosphokinase myocardial Band (CPK-MB). The mean postoperative Ejection Fraction (EF) was 36.7%±7.2% which was significantly higher than the Preoperative one (p<.05). At the end of four months to one and half year 22 patients were in NYHA class I to II and all were angina free in canadian cardiovascular society class.f Conclusions Coronary End Arterectomy without cardiopulmonary bypass can be performed in patients who are expected to benefit from complete revascularisation. It can be performed with closed as well as open method. However to achieve complete endarterectomy by closed technique in some patients it is essential to chase the plaque. Early and mid term results are encouraging.  相似文献   
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A rare case of a maxillo-mandibular band in a 21 year female patient is reported. Possibility of its being a remnant of buccaphary geal membrane is discussed in the light of clinical and histological findings.  相似文献   
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Of 132 children with bladder stones seen in 1 year, 94% were boys and 73% were aged between 1 and 5 years. Significant malnutrition and evidence of vitamin deficiency were absent. Wheat bread was the dietary staple, while the intake of milk and dairy products, eggs and meat was very low. Analysis of 29 stones showed them to consist mainly of calcium oxalate and uric acid, with small amounts of calcium phosphate and magnesium ammonium phosphate in some cases. The composition of the surface and central parts of the stones, examined in 20 cases, was usually different. The nucleus was formed almost entirely of calcium oxalate and uric acid in four and three cases respectively, whereas the surface layers were composed of other ingredients. In another case the nucleus was composed entirely of xanthine, which indicated a diagnosis of xanthinuria.  相似文献   
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Brain cyclooxygenases (COX), the rate-limiting enzyme in prostaglandin synthesis, is rapidly and transiently induced by convulsions in hippocampal and cortical neurons. Previous studies have explored the protective effect of naproxen (non-selective COX-inhibitor) or rofecoxib (selective COX-2 inhibitor) against chemical kindling in mice. With this background, the present study was designed to explore the possible effect of nimesulide (a preferential COX-2 inhibitor) against pentylenetetrazol (PTZ)-induced kindling epilepsy in mice. To induce kindling, PTZ was injected in a subconvulsive dose (40 mg/kg, i.p.) every other day for 15 days. Nimesulide (2.5 or 5 mg/kg, p.o.) was administered each day 45 min before either PTZ or vehicle challenge. The intensity of kindling was assessed immediately after PTZ administration according to a prevalidated scoring scale. On 16th day i.e. 24 h after the last dose of PTZ, animals were sacrificed and various biochemical parameters were assessed in the whole brain. Compared with normal control group, PTZ-kindled mice had significantly higher levels of malondialdehyde, nitrite, myeloperoxidase but had lower levels of reduced glutathione in the whole brain homogenate. Chronic treatment with nimesulide (2.5 or 5 mg/kg, p.o.) for 15 days showed significant decrease in kindling score and could play a role in controlling the accompanying biochemical alterations due to PTZ. These results suggested that nimesulide, a preferential COX-2 inhibitor offered neuroprotection against PTZ-induced kindling in mice.  相似文献   
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Time-resolved contrast enhanced magnetic resonance angiography (MRA) may suffer from involuntary patient motion. It is noted that while MR signal change associated with motion is large in magnitude and has smooth phase variation in k-phase, signal change associated with vascular enhancement is small in magnitude and has rapid phase variation in k-space. Based upon this observation, a novel projection onto convex sets (POCS) algorithm is developed as an automatic iterative method to remove motion artifacts. The presented POCS algorithm consists of high-pass phase filtering and convex projections in both k-space and image space. Without input of detailed motion knowledge, motion effects are filtered out, while vasculature information is preserved. The proposed method can be effective for a large class of nonrigid motions, including through-plane motion. The algorithm is stable and converges quickly, usually within five iterations. A double-blind evaluation on a set of clinical MRA cases shows that a completely unsupervised version of the algorithm produces significantly better rank scores (P=0.038) when compared to angiograms produced manually by an experienced radiologist.  相似文献   
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