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561.
The World Health Organization (WHO) Classification of Tumours of Haematopoietic and Lymphoid Tissue, 2008 edition, states that anaplastic large cell lymphoma (ALCL) is “consistently negative for Epstein-Barr virus (EBV)". The statement made by the WHO has led to the widespread belief that EBV can have no pathogenic role in ALCL. Herein we report a case of an immunocompetent 35-year-old male who presented with hemophagocytic syndrome secondary to lymphoma for which diagnostic material consisted solely of a bone marrow biopsy. The biopsy demonstrated large anaplastic cells which were uniformly positive for surface CD3, CD30 (strong membranous and Golgi expression), CD45, TIA-1 and Granzyme B but negative for ALK-1. In-situ hybridization was strongly positive for EBER in the large neoplastic cells. The uniformity of CD30 expression and positivity for cytotoxic markers on the anaplastic tumor cells raised the diagnostic possibility of an EBV-associated ALCL, ALK-. Discussion of this case as well as a retrospective review of 64 cases of reported of EBV+ ALCL are presented.  相似文献   
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STUDY DESIGN: The distribution of the lowest vertebra tangential to the suprasternal notch and the lowest intervertebral disc visualized above the sternum was determined on magnetic resonance imaging (MRI) studies. The method is illustrated in seven patients undergoing upper thoracic spinal reconstruction to define a surgical approach without sternotomy or thoracotomy. OBJECTIVES: The relation of the sternal notch to thoracic vertebrae was examined by MRI to estimate the thoracic level approachable anteriorly without sternotomy. SUMMARY OF BACKGROUND DATA: Upper thoracic spine (T1-T4) visualization is considered difficult. The thoracic vertebrae that can be visualized anteriorly without sternotomy is unknown. METHODS: The vertebral level tangential to the suprasternal notch and the lowest intervertebral disc visualized in its entirety above the sternum was determined from 106 consecutive midsagittal cervicothoracic MRI studies. The method was evaluated in seven patients to illustrate application of a low suprasternal, lateral extracavitary, or transpedicular approach to performing upper thoracic reconstruction. RESULTS: The midportion of the T3 vertebra is often above the sternal notch, whereas the trajectory of the T1-T2 intervertebral disc is usually rostral to the sternum. All four patients with disease above the sternal notch on MRI underwent a low left suprasternal approach, whereas three others were treated with a lateral extracavitary or transpedicular approach. No patient worsened neurologically and all ambulated independently after surgery. CONCLUSIONS: Upper thoracic vertebrae can be exposed without sternotomy or thoracotomy by a low left suprasternal approach. Midsagittal cervicothoracic MRI can identify the thoracic vertebrae above the sternum, thereby determining whether a low suprasternal approach is feasible. Otherwise, a lateral extracavitary or transpedicular approach can be used to avoid sternotomy or thoracotomy.  相似文献   
567.
The Botstein-Zacharopolous afterloading radiation source has been modified to facilitate its application to patients receiving intracavitary irradiation therapy. A new clamp assembly, in which each ovoid and the tandum can be separately controlled, has been designed and implemented. A study of 74 patients who alternately received the original or the modified applicator showed the time of the application procedure to be significantly less (p less than 0.001) with the modified device than it was with the original instrument. Fewer X rays were required for evaluating the placement of the modified instrument than the original applicator (p = .055).  相似文献   
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The increasing incidence of Alzheimer's disease (AD) coupled with the lack of therapeutics to address the underlying pathology of the disease has necessitated the need for exploring newer targets. Calcium dysregulation represents a relatively newer target associated with AD. Ca+2 serves as an important cellular messenger in neurons. The concentration of the Ca+2 ion needs to be regulated at optimal concentrations intracellularly for normal functioning of the neurons. This is achieved with the help of mitochondria, endoplasmic reticulum, and neuronal plasma membrane channel proteins. Disruption in normal calcium homeostasis can induce formation of amyloid beta plaques, accumulation of neurofibrillary tangles, and dysfunction of synaptic plasticity, which in turn can affect calcium homeostasis further, thus forming a vicious cycle. Hence, understanding calcium dysregulation can prove to be a key to develop newer therapeutics. This review provides detailed account of physiology of calcium homeostasis and its dysregulation associated with AD. Further, with an understanding of various receptors and organelles involved in these pathways, the review also discusses various calcium channel blockers explored in AD hand in hand with some multitarget molecules addressing calcium as one of the targets.  相似文献   
569.
Waldmann''s disease, or primary intestinal lymphangiectasia, is an unusual cause of protein‐losing enteropathy primarily characterized by lymphopenia, hypoalbuminemia, and hypogammaglobulinemia. However, variable clinical presentations result dilemmas in diagnosis and effective management. We present a toddler diagnosed with Waldmann''s disease managed with a high‐protein diet and medium‐chain triglyceride supplementation.  相似文献   
570.
How responsive neurostimulation (RNS) decreases seizure frequency is unclear. Stimulation may alter epileptic networks during inter-ictal epochs. Definitions of the epileptic network vary but fast ripples (FRs) may be an important substrate. We, therefore, examined whether stimulation of FR-generating networks differed in RNS super responders and intermediate responders. In 10 patients, with subsequent RNS placement, we detected FRs from stereo-electroencephalography (SEEG) contacts during pre-surgical evaluation. The normalized coordinates of the SEEG contacts were compared with those of the eight RNS contacts, and RNS-stimulated SEEG contacts were defined as those within 1.5 cm3 of the RNS contacts. We compared the post-RNS placement seizure outcome to (1) the ratio of stimulated SEEG contacts in the seizure-onset zone (SOZ stimulation ratio [SR]); (2) the ratio of FR events on stimulated contacts (FR SR); and (3) the global efficiency of the FR temporal correlational network on stimulated contacts (FR SGe). We found that the SOZ SR (p = .18) and FR SR (p = .06) did not differ in the RNS super responders and intermediate responders, but the FR SGe did (p = .02). In super responders, highly active desynchronous sites of the FR network were stimulated. RNS that better targets FR networks, as compared to the SOZ, may reduce epileptogenicity more.  相似文献   
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