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101.
Superparamagnetic iron oxide: enhanced detection of focal splenic tumors with MR imaging 总被引:4,自引:0,他引:4
Weissleder R; Hahn PF; Stark DD; Elizondo G; Saini S; Todd LE; Wittenberg J; Ferrucci JT 《Radiology》1988,169(2):399-403
Superparamagnetic iron oxide (AMI-25), a reticuloendothelial cell-specific contrast agent for magnetic resonance (MR) imaging, was evaluated for its ability to permit detection of splenic metastases in 18 patients. Superparamagnetic iron oxide, at a dose of 30 mumol of iron per kilogram, decreased the signal intensity of spleen from 19.5 +/- 4.8 to 3.1 +/- 2.2 (spin-echo sequence, repetition time msec/echo time msec = 1,500/42; P less than .05), without changing the signal intensity of tumor. As a result, the tumor-spleen contrast-to-noise ratio increased from 0.2 (tumor isointense relative to spleen) to 18.0 (tumor hyperintense relative to spleen). As a consequence of increased contrast, splenic tumors were detected in four of 18 patients (45 individual lesions; P less than .05), whereas nonenhanced MR imaging permitted detection of splenic lesions in only two of 18 patients (four individual lesions). Maximum tumor-spleen contrast was achieved within 60 minutes after intravenous administration. These initial clinical results indicate that MR imaging with superparamagnetic iron oxide may offer improved accuracy in the diagnosis of splenic tumors. 相似文献
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104.
Facial nerve neuromas: radiologic evaluation 总被引:3,自引:0,他引:3
Latack JT; Gabrielsen TO; Knake JE; Kemink JL; Graham MD; Gebarski SS; Yang PJ 《Radiology》1983,149(3):731
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107.
Wiebke?Hansen Carsten?Saft Jürgen?Andrich Thomas?Müller Stefan?Wieczorek J?rg?T?Epplen Larissa?ArningEmail author 《Journal of negative results in biomedicine》2005,4(1):12
Background
Huntington disease (HD) is a fully penetrant, autosomal dominantly inherited disorder associated with abnormal expansions of a stretch of perfect CAG repeats in the 5' part of the IT15 gene. The number of repeat units is highly predictive for the age at onset (AO) of the disorder. But AO is only modestly correlated with repeat length when intermediate HD expansions are considered. Recently, suggestive association has been reported between a single nucleotide polymorphism (SNP; rs1801131, also known as A1298C) in the methyltetrahydrofolate reductase (MTHFR) gene and AO of HD. 5,10-MTHFR is a key enzyme in the folate metabolism, diverting metabolites toward methylation reactions or nucleotide synthesis. Using part of a previously established study cohort plus additional patients and appropriate statistical methods, we reinvestigated two polymorphisms in the MTHFR gene, C677T and A1298C, as well as their association with AO in 167 HD patients. 相似文献108.
Jagiello P Klein W Schultz H Csernok E Gross WL Epplen JT 《International journal of immunogenetics》2005,32(1):3-6
In antineutrophil cytoplasmatic antibody (ANCA)-associated vasculitides (AAV), bactericidal/permeability increasing protein (BPI) ANCAs are detected. Recent observations suggest that BPI-ANCAs can potentially contribute to a proinflammatory setting in the absence of proteinase 3 (PRTN3) ANCAs during the development of a pulmonary relapse by impeding the elimination of Gram-negative bacteria (GNB). However, it is as yet not clear whether the genetic background contributes to the generation of BPI-ANCAs in Wegener granulomatosis (WG) or if BPI polymorphisms are associated with WG. In this study we genotyped the functionally relevant single nucleotide polymorphism (SNP) A645 (Glu216Lys) of the BPI gene in 201 WG patients and 608 healthy controls. To investigate whether further SNPs might be associated with WG, we also examined an intragenic microsatellite marker. No significant differences were found between patients and controls. Thus BPI polymorphisms do not appear to contribute to genetic predisposition to WG. Moreover, our data do not suggest a genetic background for the generation of BPI-ANCAs in WG. 相似文献
109.
van Uden CJ Nieman FH Voss GB Wesseling G Winkens RA Crebolder HF 《BMC health services research》2005,5(1):27
Background
In recent years, Dutch general practitioner (GP) out-of-hours service has been reorganised into large-scale GP cooperatives. Until now little is known about GPs' experiences with working at these cooperatives for out-of-hours care. The purpose of this study is to gain insight into GPs' satisfaction with working at GP cooperatives for out-of-hours care in separated and integrated cooperatives. 相似文献110.
Among patients with metastatic urothelial cancer of the bladder, 16-25% develop peritoneal carcinomatosis. In the majority of cases peritoneal carcinomatosis is associated with multiple metastatic sites. Peritoneal metastases as the single site of metastatic deposits are rare and they have been described following laparoscopic radical nephroureterectomy or cystectomy. We report on a patient who developed peritoneal carcinomatosis as the single site of metastases 8 months after robotic-assisted radical cystectomy, extended pelvic lymphadenectomy and extracorporeal formation of an ileal neobladder for organ-confined, muscle-invasive and poorly differentiated bladder cancer. The indication for robotic-assisted radical cancer surgery for urothelial carcinoma of the upper or the lower urinary tract in patients with locally advanced or poorly differentiated cancer should be made with caution. 相似文献