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1.
Myelofibrosis with myeloid metaplasia (MMM) is currently classified as a classic (ie, BCR-ABL-negative) myeloproliferative disorder characterized by anemia, multiorgan extramedullary hematopoiesis, constitutional symptoms, and premature death from either leukemic transformation or other disease complications. Stem cell transplantation can be curative, but many patients either are not appropriate candidates or do not choose to accept the significant risks associated with transplantation. Current pharmacologic therapy has been beneficial mainly in terms of palliating disease-associated cytopenias, constitutional symptoms, splenomegaly, and other organ damage from excess myeloproliferation. Novel treatment strategies are under investigation, including targeted inhibition of JAK2V617F, the activating tyrosine kinase point mutation present in about half of patients with MMM. In this article, we review both the old and new pharmacologic options for MMM.  相似文献   
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Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma   总被引:9,自引:3,他引:6  
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study.  相似文献   
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Unilateral pseudobulbar syndrome with limited capsulothalamic infarction   总被引:5,自引:0,他引:5  
A unilateral pseudobulbar syndrome consequent to unilateral capsulothalamic infarction is described. Motor deficit of the face was associated with marked velar and pharyngeal unilateral palsy; paresis of limbs was mild. ACT scan revealed a circumscribed infarction of the genu of the internal capsule. This raised the problem of unilateral supranuclear pharyngeal palsies and of the precise anatomy of the genicular tract in the genu of the internal capsule.  相似文献   
5.
Dural sinus thrombosis: study using intermediate field strength MR imaging   总被引:1,自引:0,他引:1  
The magnetic resonance (MR) images of six patients with thrombosis of a dural sinus were reviewed. The diagnosis had been verified by computed tomographic scans in three patients and arteriograms in two; in the sixth patient, only MR imaging was used to confirm the clinical syndrome. In all patients, high-intensity signal was seen from the thrombus within the affected dural sinus on all echoes. This persistent signal intensity allowed intravascular clot to be distinguished from normal causes of increased signal such as flow-related enhancement (entry phenomenon) and even-echo rephasing. MR imaging demonstrated the cause of the thrombosis in three patients: two were secondary to adjacent tumors, and one was secondary to unsuspected mastoiditis. Complications such as infarction were also demonstrated. Using MR imaging, one can easily and safely diagnose thrombosis of a dural sinus. MR should be the imaging method of choice in patients suspected of having thrombosis of a dural sinus.  相似文献   
6.
Reiman  TH; Heiken  JP; Totty  WG; Lee  JK 《Radiology》1988,169(2):564-566
Limited-field-of-view radio-frequency receiver antennas provide improved near-field sensitivity for magnetic resonance imaging by decreasing the antenna volume. The Helmholtz-type surface coil, consisting of two flat rings, is an organ-encompassing antenna that takes advantage of this principle to yield an improved signal-to-noise ratio (S/N). The coil was tested in a group of 50 patients and 16 healthy volunteers. Images obtained with the Helmholtz coil demonstrated quantitatively superior S/N of 2.2-fold or greater than that of comparison body coil images, as well as qualitatively superior anatomic resolution.  相似文献   
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We describe a technique for conducting a CT-guided biopsy of the brachial plexus region, report two illustrative cases, discuss potential complications, and conclude that, in selected cases, biopsy of lesions in the region of the brachial plexus can be performed safely with CT guidance.  相似文献   
9.
To ascertain the magnetic resonance (MR) imaging characteristics of pheochromocytomas and paragangliomas and to compare MR with computed tomography (CT) and iodine-131 metaiodobenzylguanidine (I-131 MIBG), 19 patients (18 with pheochromocytomas, one with a paraganglioma) were studied. The 18 patients with pheochromocytomas had had positive findings with I-131 MIBG scintigraphy. Abdominal pheochromocytomas were generally hypointense compared with normal liver on T1-weighted MR images and extremely hyperintense on T2-weighted MR images. MR imaging was preferable to CT in the evaluation of primary pheochromocytomas due to superior tissue characterization, particularly in the patient with hypertension and borderline catecholamine levels. For patients with recurrent or metastatic disease, the data suggest that I-131 MIBG scintigraphy is the examination of choice.  相似文献   
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OBJECTIVE: The objective of this retrospective cohort study was to determine whether coronary artery bypass graft (CABG) surgery is effective and cost-effective relative to medical management of coronary artery disease (CAD) in the elderly. SUMMARY BACKGROUND DATA: The aging of the U.S population and the improvements in surgical techniques have resulted in increasing numbers of elderly patients who undergo this surgery. The three randomized, controlled trials (RCTs) that established the efficacy of CABG surgery completed patient enrollment from 19 to 24 years ago excluded patients older than 65 years. Although information regarding outcomes of CABG in this population is mainly available in case series, a major lacuna exists with respect to information on quality of life and cost effectiveness of surgery as compared with medical management. METHODS: The authors retrospectively formed surgical and medically managed cohorts of octogenarians with significant multivessel CAD. More than 600 medical records of patients older than 80 years who underwent angiography at our institution were reviewed to identify 48 patients who were considered reasonable surgical candidates but had not undergone surgery. This cohort was compared with 176 patients who underwent surgery. RESULTS: The cost per quality-adjusted life year saved was $10,424. At 3 years, survival in the surgical group was 80% as compared with 64% in the entire medical cohort and 50% in a smaller subset of the medical cohort. Quality of life in patients who underwent surgery was measurably better than that of the medical cohort with utility index scores, as measured by the EuroQoL, (a seven-item quality of life questionnaire) of 0.84, 0.61, and 0.74, respectively. CONCLUSIONS: Performing CABG surgery in octogenarians is highly cost-effective. The quality of life of the elderly who elect to undergo CABG surgery is greater than that of their cohorts and equal to that of an average 55-year-old person in the general population.  相似文献   
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