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排序方式: 共有447条查询结果,搜索用时 15 毫秒
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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
Weisenburger DD; Gordon BG; Vose JM; Bast MA; Chan WC; Greiner TC; Anderson JR; Sanger WG 《Blood》1996,87(9):3860-3868
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
3.
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
4.
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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Low-artifact intravascular devices: MR imaging evaluation 总被引:2,自引:0,他引:2
Teitelbaum GP; Ortega HV; Vinitski S; Stern H; Tsuruda JS; Mitchell DG; Rifkin MD; Bradley WG Jr 《Radiology》1988,168(3):713-719
Flow-phantom magnetic resonance (MR) imaging, with use of both spin-echo (SE) and gradient-echo (GRE) techniques at 1.5 T, was performed on the percutaneous Greenfield (beta-III titanium alloy [TMA wire]), Amplatz (MP32-N alloy), and Simon nitinol filters and TMA wire facsimiles of the bird's nest, Gunther, new retrievable, and Amplatz vena caval filters. SE imaging allowed detection of thrombi as small as 5 X 5 mm trapped within the percutaneous Greenfield, Simon nitinol, and TMA-wire facsimile filters; with the MP32-N Amplatz filter, a larger volume of thrombus (10 X 20-mm clots) was necessary for clot detection. GRE imaging allowed detection of intraluminal tilting of the percutaneous Greenfield and facsimile Amplatz (TMA-wire) filters. GRE imaging was useful for demonstrating postfilter turbulence due to clots, which was greatest for the Amplatz filter. Imaging of facsimile vascular devices made of tantalum or TMA wire did not cause the severe "black-hole" MR artifacts typical of the stainless-steel devices. SE and GRE imaging were very useful for determining caval patency in two patients with previously placed Mobin-Uddin filters. Noninvasive MR evaluation of blood vessels in the presence of a variety of low-artifact intravascular devices appears feasible. 相似文献
7.
M M Stilmant W G Couser R S Cotran 《Laboratory investigation; a journal of technical methods and pathology》1975,32(6):746-756
Mice undergoing prolonged (5 to 8 weeks) immunization with cadium-free feeritin were studied 1 to 32 days following the last ferritin injection. Urine protein was measured and renal tissue examined by light, immunofluorescence, and electron microscopy. Immunized animals developed significant proteinuria and circulating antibody to ferritin.by light microscopy, proetinuric animals had a proliferative glomerular lesion with mesangial hypercellularity and martrix increase, focal and segmental necrosis, fibrin deposits, and occasional crescents. Iron stains revealed prominent mesangial iron deposition. In immunized animals, IgG and C3 deposits were localized mainly in the mesanglium. Electron microscopic studies revealed marked deposition of ferratin complexesexpanded mesangial matrix and mesangial interposition. Ferratin immune complexes were also visualized in epithelial spaces. In the latter location ferritin immune complexes occasionally formed characteristic electron-dense subepithelial deposits. In this model, mesangial and subepithelial localization of autologous ferritin immune complexes is associated with development of glomerulonephritis and characteristic mesangial lesions resembling those seen in some types of human glomerulonephritis. 相似文献
8.
Mesangial lesions and focal glomerular sclerosis in the aging rat. 总被引:11,自引:0,他引:11
W G Couser M M Stilmant 《Laboratory investigation; a journal of technical methods and pathology》1975,33(5):491-501
The pathogenesis of focal glomerular sclerosis (FGS) and its relation to proteinuria and idiopathic nephrotic syndrome are unknown. Urine protein excretion in Sprague-Dawley rats increased with age. Fifty per cent of 12-month and 90 per cent of 24-month-old animals were proteinuric (greater than 20 mg. per day). Heavily proteinuric old rats manifested biochemical changes characteristic of nephrotic syndrome without significant loss of renal function. Three-month, 6-month, and nonproteinuric 12-month-old animals had mesangial deposits of IgM in occasional lobules of some glomeruli and slight mesangial hyperplasia. Four proteinuric 12-month-old rats had diffuse 4+ deposits of IgM in the mesangium of most glomeruli, basement membrane thickening and epithelial cell foot process fusion without FGS. The mesangial IgM deposits eluted in acid buffer and did not fix complement. Six proteinuric 12-month-old rats had focal and segmental areas of glomerular sclerosis with adhesions to Bowman's capsule, foamy cells, intraluminal eosinophilic deposits and capillary wall wrinkling and collapse. These lesions were more advanced in 24-month-old animals. Nonproteinuric 24-month-old rats did not have detectable FGS. Mesangial uptake of colloidal carbon was normal in proteinuric and nonproteinuric animals without FGS. Mesangial uptake of colloidal carbon was normal in proteinuric and nonproteinuric animals without FGS and reduced in proteinuric animals with FGS. In the aging rat the development of proteinuria and mesangial IgM deposition apparently precede development of a focal sclerotic glomerular lesion with histologic and ultrastructural features similar to FGS in man. The generalized impairment of mesangial phagocytic function in proteinuric rats with FGS suggests that this lesion may result from mesangial overload and dysfunction consequent to the persistent increase in glomerular permeability and proteinuria. 相似文献
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10.
WG Mitchell H Lynn JF Bale MA Maeder SM Donfield B Garg AH Tilton JK Willis TP Bohan 《Pediatrics》1997,100(5):817-824
BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function. 相似文献