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11.
BRCA1 and BRCA2 are major breast cancer susceptibility genes. Nineteen single nucleotide polymorphisms (SNPs) at 18 loci have been associated with breast cancer. We aimed to determine whether these predict breast cancer incidence in women with BRCA1/BRCA2 mutations. BRCA1/2 mutation carriers identified through the Manchester genetics centre between 1996 and 2011 were included. Using published odds ratios (OR) and risk allele frequencies, we calculated an overall breast cancer risk SNP score (OBRS) for each woman. The relationship between OBRS and age at breast cancer onset was investigated using the Cox proportional hazards model, and predictive ability assessed using Harrell's C concordance statistic. In BRCA1 mutation carriers we found no association between OBRS and age at breast cancer onset: OR for the lowest risk quintile compared to the highest was 1.20 (95% CI 0.82–1.75, Harrell's C = 0.54), but in BRCA2 mutation carriers the association was significant (OR for the lowest risk quintile relative to the highest was 0.47 (95% CI 0.33–0.69, Harrell's C = 0.59). The 18 validated breast cancer SNPs differentiate breast cancer risks between women with BRCA2 mutations, but not BRCA1. It may now be appropriate to use these SNPs to help women with BRCA2 mutations make maximally informed decisions about management options.  相似文献   
12.
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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14.
Magnetic resonance installation: siting and economic considerations   总被引:1,自引:0,他引:1  
Bradley  WG; Opel  W; Kassabian  JP 《Radiology》1984,151(3):719
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16.
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   
17.
Wilson  AJ; Totty  WG; Murphy  WA; Hardy  DC 《Radiology》1989,173(2):329-333
One hundred two computed tomographic (CT) arthrograms of the shoulder were retrospectively reviewed and compared with conventional double-contrast arthrograms from 101 patients (24 females and 77 males aged 9-70 years). One- to 4-year follow-up was obtained in 84 patients, 40 of whom underwent open-shoulder surgery or arthroscopy. Morphology of the normal portions of each labrum was categorized according to length, width, and tip shape. Correlation between morphology and age was weak, but abnormal labra were more common in younger patients. Conventional radiography was more accurate for detecting bony glenoid margin fractures, but CT was more accurate for detecting Hill-Sach fractures. CT was also more reliable than conventional arthrography in the detection of rotator cuff tears. Hence, few if any conventional radiographs are necessary between contrast material injection and CT imaging. A reduction in the number of images obtained will result in decreased radiation dose, less cost, and shorter examination time without loss of diagnostic accuracy.  相似文献   
18.
Schertz  LD; Lee  JK; Heiken  JP; Molina  PL; Totty  WG 《Radiology》1989,173(2):401-405
The contribution of proton spectroscopic (PS) imaging to magnetic resonance (MR) imaging of the liver was assessed at 0.5 T in 55 patients with known or suspected hepatic malignancy. PS images were compared subjectively with T1- and T2-weighted spin-echo (SE) images for hepatic lesion detection and conspicuity. For hepatic metastases (n = 27), PS images were equal to T1-weighted images in lesion detection in 17 patients but showed fewer lesions in five patients and false-negative results in two. When compared with T2-weighted images, PS images depicted more lesions in six patients, an equal number of lesions in 18, and fewer lesions in two. Hepatomas (n = 8) were detected with each sequence in all patients. Hepatomas were often more conspicuous on PS images than on T2-weighted images; they were of equal conspicuity on PS and T1-weighted images in most cases. Whereas fatty infiltration (n = 16) appeared on PS images as areas of low signal intensity similar to that of paraspinal muscle, it produced no detectable abnormality on either T1- or T2-weighted images. PS imaging is inferior to T1-weighted SE imaging in the detection of hepatic metastases. The major role of PS imaging at intermediate field strength is to differentiate focal fatty infiltration from hepatic metastases.  相似文献   
19.

Objectives

To investigate established prognostic factors and relatively new histopathological tumor characteristics including metric substage and lamina propria invasion patterns in a large series of T1 high‐grade non‐muscle‐invasive bladder cancer.

Methods

Between 1989 and 2012, 322 patients with initial stage T1 high‐grade bladder cancer underwent transurethral resection, followed by re‐transurethral resection and a conservative approach with follow‐up regime alone or instillation treatment. Transurethral resection specimens were reassessed by two experienced urological pathologists for tumor grade according to the World Health Organization 1973 classification, metric T1 substage, lamina propria invasion pattern and associated carcinoma in situ. The median follow‐up period was 42 months (interquartile range 25–72 months). In addition to Kaplan–Meier analyses, uni‐ and multivariable Cox regression analyses were used to compare progression‐free survival, cancer‐specific survival and overall survival for the studied parameters comparing two subcohorts.

Results

While in patients after instillation treatment no examined feature was shown as an independent predictor for prognosis, there were predictive histopathological features in multivariable Cox regression analyses in instillation treatment‐naïve patients: associated carcinoma in situ (hazard ratio 2.278, 95% confidence interval 1.119–4.634, P = 0.023) and World Health Organization 1973 grade 3 (hazard ratio 2.950, 95% confidence interval 1.021–8.536, P = 0.046) for worse progression‐free survival, infiltrative lamina propria tumor pattern for worse cancer‐specific survival (hazard ratio 2.369, 95% confidence interval 1.034–5.429, P = 0.042) and overall survival (hazard ratio 1.049, 95% confidence interval 1.024–1.075, P = 0.001).

Conclusions

The results of the present T1 high‐grade bladder cancer series suggest that lamina propria invasion pattern is a promising parameter to predict the prognosis of T1 high‐grade bladder cancer in an instillation treatment‐naïve subcohort. Prospective multicenter evaluations are warranted. The need for instillation treatment in T1 high‐grade bladder cancer is clearly demanded.  相似文献   
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