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排序方式: 共有1038条查询结果,搜索用时 15 毫秒
91.
Although myeloid sarcomas (MS) are frequently associated with acute myeloid leukaemia (AML), the occurrence of mediastinal MS is a much rarer event. The authors describe a distinct group of three AML patients with mediastinal MS and complex cytogenetics presenting at their centre over a 7-year period. Clinical features consistent with superior vena caval obstruction were noted at presentation in two of the three patients. Mediastinal mass was detected on routine chest radiography, and biopsies confirmed the diagnosis of MS. One patient relapsed after consolidation chemotherapy and died from progressive disease. Two patients underwent allogeneic haemopoietic stem cell transplant, but succumbed to transplant related complications. Review of mediastinal MS over the last 20 years shows that a significant proportion of patients have complex cytogenetic abnormalities and a poor long-term prognosis. Early and accurate diagnosis is essential and patients should be managed along the lines of high risk AML.  相似文献   
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Cellular-level anatomical data from early fetal brain are sparse yet critical to the understanding of neurodevelopmental disorders. We characterize the organization of the human cerebral cortex between 13 and 15 gestational weeks using high-resolution whole-brain histological data sets complimented with multimodal imaging. We observed the heretofore underrecognized, reproducible presence of infolds on the mesial surface of the cerebral hemispheres. Of note at this stage, when most of the cerebrum is occupied by lateral ventricles and the corpus callosum is incompletely developed, we postulate that these mesial infolds represent the primordial stage of cingulate, callosal, and calcarine sulci, features of mesial cortical development. Our observations are based on the multimodal approach and further include histological three-dimensional reconstruction that highlights the importance of the plane of sectioning. We describe the laminar organization of the developing cortical mantle, including these infolds from the marginal to ventricular zone, with Nissl, hematoxylin and eosin, and glial fibrillary acidic protein (GFAP) immunohistochemistry. Despite the absence of major sulci on the dorsal surface, the boundaries among the orbital, frontal, parietal, and occipital cortex were very well demarcated, primarily by the cytoarchitecture differences in the organization of the subplate (SP) and intermediate zone (IZ) in these locations. The parietal region has the thickest cortical plate (CP), SP, and IZ, whereas the orbital region shows the thinnest CP and reveals an extra cell-sparse layer above the bilaminar SP. The subcortical structures show intensely GFAP-immunolabeled soma, absent in the cerebral mantle. Our findings establish a normative neurodevelopment baseline at the early stage.  相似文献   
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We report our experience of endovascular repair of infrarenal abdominal aortic aneurysms (EVAR) using the modular AneuRx Stent Graft System. We retrospectively reviewed the outcomes of 113 patients who underwent EVAR with the AneuRx system performed at our institution between October 1999 and August 2003. The mean age of this group was 72.5 years, with 71% (n = 80) over the age of 70 years and 95% (n = 107) males. Aneurysm diameter ranged 4.0-9.0 cm, with 33% (n = 37) >6.0 cm. The average duration of late follow-up was 32.6 +/- 24.8 months (median = 37). Successful deployment of the modular AneuRx system was noted in all patients. There were no immediate operative conversions, deaths within 24 hr of operation, or type I or III endoleaks observed at the completion of the procedure. Thirty-day mortality was 3.5% (n = 4). Acute deployment-related complications occurred in 10% (n = 13) of patients and included misdeployment, operative bleeding, arterial perforation/dissection, and access site complications. Acute systemic complications were present in nine patients, predominantly renal and cardiac complications. An endoleak noted at any time occurred in 25% of patients, with 40% of those requiring a secondary intervention. Two patients suffered late aneurysm rupture due to a type I endoleak and graft infection. Kaplan-Meier analysis revealed 5-year freedom from secondary intervention of 72.4%; freedom from aneurysm-related death of 93.9%; and probability of survival based on all-cause mortality of 60.1%. Endovascular treatment with the modular AneuRx Stent Graft System is safe and effective, producing acceptable rates of disease-free survival and mid-term clinical outcome.  相似文献   
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Cerebral ischemia is the leading cause for long-term disability and mortality in adults due to massive neuronal death. Currently, there is no pharmacological treatment available to limit progressive neuronal death after stroke. A major mechanism causing ischemia-induced neuronal death is the excessive release of glutamate and the associated overexcitation of neurons (excitotoxicity). Normally, GABAB receptors control neuronal excitability in the brain via prolonged inhibition. However, excitotoxic conditions rapidly downregulate GABAB receptors via a CaMKII-mediated mechanism and thereby diminish adequate inhibition that could counteract neuronal overexcitation and neuronal death. To prevent the deleterious downregulation of GABAB receptors, we developed a cell-penetrating synthetic peptide (R1-Pep) that inhibits the interaction of GABAB receptors with CaMKII. Administration of this peptide to cultured cortical neurons exposed to excitotoxic conditions restored cell surface expression and function of GABAB receptors. R1-Pep did not affect CaMKII expression or activity but prevented its T286 autophosphorylation that renders it autonomously and persistently active. Moreover, R1-Pep counteracted the aberrant downregulation of G protein-coupled inwardly rectifying K+ channels and the upregulation of N-type voltage-gated Ca2+ channels, the main effectors of GABAB receptors. The restoration of GABAB receptors activated the Akt survival pathway and inhibited excitotoxic neuronal death with a wide time window in cultured neurons. Restoration of GABAB receptors and neuroprotective activity of R1-Pep was verified by using brain slices prepared from mice after middle cerebral artery occlusion (MCAO). Treatment with R1-Pep restored normal GABAB receptor expression and GABA receptor-mediated K+ channel currents. This reduced MCAO-induced neuronal excitability and inhibited neuronal death. These results support the hypothesis that restoration of GABAB receptor expression under excitatory conditions provides neuroprotection and might be the basis for the development of a selective intervention to inhibit progressive neuronal death after ischemic stroke.  相似文献   
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One of the serious complications during a routine endodontic procedure is accidental ingestion/aspiration of the endodontic instruments, which can happen when proper isolation is not done. There are at present no clear guidelines whether foreign body ingestion in the gastrointestinal tract should be managed conservatively, endoscopically or surgically. A 5 year old boy reported to the Department of Pediatric and Preventive Dentistry, D.A. Pandu Memorial R.V. Dental College, Bangalore, India, with a complaint of pain and swelling in the lower right back teeth region. Endodontic therapy was planned for the affected tooth. During the course of treatment the child accidentally swallowed a 21 mm 15 size K file. Endoscopy was performed immediately but the instrument could not be retrieved. The instrument passed out uneventfully along with the stools 48 h after ingestion.Careful evaluation of the patient immediately after the accident helps in managing the patient effectively along with following the recommended guidelines.  相似文献   
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