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排序方式: 共有898条查询结果,搜索用时 15 毫秒
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Intratemporal vascular tumors: detection with CT and MR imaging 总被引:1,自引:0,他引:1
Lo WW; Shelton C; Waluch V; Solti-Bohman LG; Carberry JN; Brackmann DE; Wade CT 《Radiology》1989,171(2):445-448
The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion. 相似文献
4.
骨巨细胞瘤的MRI诊断价值 总被引:10,自引:0,他引:10
目的探讨骨巨细胞瘤的MRI表现特点及其病理基础。资料与方法搜集经手术病理证实的12例骨巨细胞瘤患者资料,分析其MRI征象并与病理结果对照。结果T1WI上肿瘤实体表现为低、等信号,T2WI上为不均匀高信号,Gd-DTPA增强扫描呈中度到明显强化。此外,MRI还可显示肿瘤内坏死、出血、含铁血黄素沉着等。结论MRI能够提供比较全面的影像学信息,可提高对骨巨细胞瘤诊断的准确性。 相似文献
5.
On the basis of x-ray morphometric examinations employing 2,500 x-ray photographs age- and sex-specific standard value curves of the bone mineral content are ascertained for the methods by Singh, Saville and Barnett/Nordin. Evaluations leads to the refusal of the wide clinical application of these methods. The combined application of these methods with microradioscopy employed in the forefield diagnostics of demineralizing skeleton diseases is possible only with proviso. 相似文献
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Joseph Levine Mirtha Gonsalves Izak Babur Shaul Stier Avner Elizur Ora Kofman R. H. Belmaker 《Human psychopharmacology》1993,8(1):49-53
Inositol is an important precursor for second messenger synthesis and has been reported to be reduced by lithium treatment in rat brain and in human CSF in depression. An open trial of 6 g/day in 11 depressed patients resistant to previous treatment led to major improvement in nine patients. The enzyme synthesizing inositol has been reported to be elevated in schizophrenia, suggesting an attempted compensation for possible inositol deficiency. A controlled double-blind crossover trial in 10 chronic schizophrenic patients of 6 g/day of inositol for 30 days did not reveal any benefit. 相似文献
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Novel proteins with binding specificity for DNA CTG repeats and RNA CUG repeats: implications for myotonic dystrophy 总被引:7,自引:6,他引:7
While an unstable CTG triplet repeat expansion is responsible for myotonic
dystrophy, the mechanism whereby this genetic defect induces the disease
remains unknown. To detect proteins binding to CTG triplet repeats, we
performed bandshift analysis using as probes double- stranded DNA fragments
having CTG repeats [ds(CTG)6-10] and single- stranded oligonucleotides
having CTG repeats ss(CTG)8 or RNA CUG triplet repeats (CUG)8. The source
of protein was nuclear and cytoplasmic extracts of HeLa cells, fibroblasts
and myotubes. Proteins binding to the double-stranded DNA repeat
[ds(CTG)6-10], were inhibited by nonlabeled ds(CTG)6-10, but not by a
non-specific DNA fragment (USF/AD-ML). Another protein binding to ssCTG
probe and RNA CUG probe was inhibited by nonlabeled (CTG)8 and (CUG)8.
Nonlabeled oligos with different triplet repeat sequences, ss(CAG)8 or
ss(CGG)8, did not inhibit binding to the ss(CTG)8 probe. However, when
labeled as probes, the (CAG)8 and (CGG)8 bound to proteins distinct from
the CTG proteins and binding was inhibited by nonlabeled (CAG)8 or (CGG)8
respectively. The protein binding only to the RNA repeat (CUG)8 was
inhibited by nonlabeled (CUG)8 but not by nonlabeled single- or
double-stranded CTG repeats. Furthermore, the CUG-BP exhibited no binding
to an RNA oligonucleotide of triplet repeats of the same length but having
a different sequence, CGG. The CUG binding protein was localized to the
cytoplasm, whereas dsDNA binding proteins were localized to the nuclear
extract. Thus, several trinucleotide binding proteins exist and their
specificity is determined by the triplet sequence. The novel protein,
CUG-BP, is particularly interesting since it binds to triplet repeats known
to be present in myotonin protein kinase mRNA which is responsible for
myotonic dystrophy.
相似文献
10.
Outbreak of carbapenem-resistant Acinetobacter baumannii producing the OXA-23 enzyme in Curitiba,Brazil 总被引:19,自引:0,他引:19
Dalla-Costa LM Coelho JM Souza HA Castro ME Stier CJ Bragagnolo KL Rea-Neto A Penteado-Filho SR Livermore DM Woodford N 《Journal of clinical microbiology》2003,41(7):3403-3406
Carbapenem-resistant Acinetobacter baumannii isolates were obtained from eight patients in two hospitals in Curitiba, Brazil. The isolates were multiresistant, belonged to a single strain, and produced the OXA-23 carbapenemase. Treatment options were limited, although the isolates were susceptible to polymyxin B in vitro. The strain contributed to the deaths of five patients. 相似文献