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631.
632.
Wilms tumor in children: abdominal CT and US evaluation   总被引:1,自引:0,他引:1  
Reiman  TA; Siegel  MJ; Shackelford  GD 《Radiology》1986,160(2):501-505
Computed tomographic (CT) scans and sonograms of 13 children with Wilms tumor were reviewed to determine the ability of each imaging test to characterize the tumor and determine its extent. The findings of this review were correlated with diagnoses based on surgical and pathologic evidence. Tumor necrosis and a pseudocapsule were detected more often using CT scans than sonograms. CT scanning also was more sensitive in assessing perinephric extension, lymph node involvement, and bilateral tumors. Overall, CT scans allowed better determination of the extent of a suspected tumor, enabling correct diagnosis in 77% of patients, while US study was correct in only 23%.  相似文献   
633.
The abnormal prostate: MR imaging at 1.5 T with histopathologic correlation   总被引:4,自引:0,他引:4  
Carrol  CL; Sommer  FG; McNeal  JE; Stamey  TA 《Radiology》1987,163(2):521-525
Thirteen patients with biopsy-proved adenocarcinoma were prospectively examined with magnetic resonance (MR) imaging with use of a 1.5-T superconducting magnet. All patients subsequently underwent radical prostatectomy and careful, axial, histologic mapping of prostatic disease. Histologic findings were recorded on serial, axial diagrams to ensure precise pathologic correlation with the MR images. MR permitted identification of eight of 12 (67%) adenocarcinomas as hypointense foci (relative to the surrounding, higher intensity, peripheral zone); but tumor volume was under-estimated with MR imaging in five of eight cases (63%). Nodules of prostatic hyperplasia were identified correctly in only one of nine patients (11%). These findings suggest that, despite that fact that high field strength MR imaging currently does not depict all pathologic foci within the prostate, it may be of predictive value in the differential diagnosis of prostatic abnormalities when their locations are demonstrable.  相似文献   
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Clinical safety of gadopentetate dimeglumine   总被引:3,自引:1,他引:2  
  相似文献   
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TA Lane 《Transfusion》1989,29(5):418-420
Malignancy in a potential autologous blood donor is considered by some as a relative contraindication for the collection of autologous blood. There is, however little experimental information regarding the safety of transfusion of autologous blood that may contain viable tumor cells. The purpose of this study was to determine if tumor cells seeded into autologous blood retain their metastatic potential and, if so, for how long. A well-established model of the pulmonary metastasis of B16/F10 (F10) melanoma in C57BL/6 mice was used. Equal numbers of F10 cells were seeded into CPDA-1 blood from the mice or into saline, and the number of lung tumors was evaluated 14 days after infusion of blood or saline. The CPDA-1 blood seeded with F10 cells was stored for up to 21 days in transfer packs at 4 to 6 degrees C, and the metastatic potential of F10 cells in the stored blood was ascertained as above. F10 cells seeded into autologous blood that was then transfused without storage gave rise to the same number of metastatic foci (404 +/- 32 metastases) as did those cells transfused in saline (374 +/- 38, p = 0.5). In contrast, the number of metastatic foci resulting from the transfusion of blood containing F10 cells decreased progressively after storage of the blood (7 days = 124 +/- 14 metastases; 14 days = 7 +/- 1; 21 days = 2 +/- 1; all p values less than 0.001 vs fresh blood). Also, the predilection of F10 cells to metastasize to the lung was unchanged by storage in blood.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
639.
1. Normal subjects (n = 5; age 20-42 years; mean resting blood pressure (± 1 s.d.) 116±21/61±11 mmHg) underwent cardiovascular reflex testing five times each. On every occasion systolic blood pressure (SBP) responses to sustained handgrip (GRIP) and cold pressure (COLD) tests were measured and continuous non-invasive SBP and heart period (RRINT) data were analysed in the frequency domain using fast Fourier transforms. Power spectral (PS) density estimates of high frequency/total power (HF%; a measure of vagal activity), low frequency/HF ratio (LF/HF; a measure mainly of cardiovascular sympathetic activity for heart period) and low frequency/total power (LF%; a proposed measure of sympathetic activity for SBP) at rest, during and 2min after the end of stimuli were calculated. 2. The data from the rest and recovery periods did not differ and showed that cardiovascular recovery to baseline measures following sympathetic stimulation occurred within 2 min. 3. There was a significant rise in SBP with GRIP and COLD. The LF/HF(RRINT) rose significantly with GRIP, but not with COLD. The LF%(SBP) did not change significantly with GRIP or COLD. 4. The SBP and PS analyses showed low intra-individual reproducibility of responses to reflex tests, with coefficients of variation for PS measures at rest of 25-41% and on sympathetic stimulation of up to 80%. 5. The high variability of these observations indicates that PS methods may not be suitable for the analysis of transient cardiovascular reflexes.  相似文献   
640.
Megalocephaly and hypodense extracerebral fluid collections   总被引:1,自引:0,他引:1  
  相似文献   
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