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81.
Pancreas divisum: thin-section CT   总被引:1,自引:0,他引:1  
Twelve patients with known pancreas divisum underwent thin-section computed tomography (CT) to determine the capability of CT to depict this pancreatic anomaly. Focal pancreatic enlargement was present in five patients. Two distinct pancreatic moieties separated by a fat cleft were noted in three patients; a fourth patient had focal atrophy in the distribution of the dorsal pancreas. The two pancreatic moieties were identified at the same craniocaudal level in all four of these patients. The dorsal duct was depicted in all 12 patients, while the short ventral duct was seen in only five of the 12 patients. Failure of the ventral and dorsal pancreatic ducts to fuse was identified in all five patients in whom both ducts were seen. CT may not enable specific diagnosis of pancreas divisum in the majority of patients. If, however, distinct pancreatic moieties or unfused ductal systems are evident, the diagnosis may be confidently suggested.  相似文献   
82.
Ligation of the hepatic artery has been successfully used in the management of massive bleeding, secondary to hepatic trauma, and in the treatment of metastatic neoplastic disease. The indications for a concomitant cholecystectomy are less well defined. It is generally accepted that cholecystectomy should be performed when ligation is used to control bleeding. In our study, ligation of the hepatic artery was performed, leaving the gallbladder in situ. At autopsy, no pathologic process could be detected in the gallbladder. Microscopic analysis showed fibrosis in the mucosal surface, mild chronic inflammation and nonspecific mononuclear infiltration. We conclude that the changes are insufficient to warrant the removal of a normal gallbladder when ligation of the hepatic artery is performed as treatment for neoplastic disease.  相似文献   
83.
Caroline  DF; Pollack  HM; Banner  MP; Schneck  C 《Radiology》1985,155(2):311-313
Patients being evaluated as potential renal transplant recipients routinely undergo voiding cystourethrography. Eight patients were encountered in whom extraperitoneal extravasation was noted from the region of the ureterovesical junction during voiding (seven patients) or during filling (one patient). Extravasation was bilateral in six patients and unilateral in two. The patients neither experienced symptoms related to the extravasation, required treatment, nor had sequelae. Five of the eight patients have subsequently received renal transplants and their bladders were observed to be normal at surgery. Cystoscopy was also performed in two of these five patients and was unremarkable. After transplantation, these patients' bladders functioned normally and gave rise to no symptoms.  相似文献   
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Multiple studies demonstrate the efficacy of colorectal cancer (CRC) screening in patients over 50 years of age. However, there is a lack of consensus regarding which screening method to use, and compliance has been poor. The objective of this study was to identify the CRC screening practices at two institutions and determine the relationship between screening and pathologic stage for patients presenting with a colorectal neoplasm. This study, conducted at the University of Virginia (UVA) Health System and the Salem Veterans Affairs Medical Center (VAMC) between October 30, 2000, and September 1, 2004, included 198 patients > or = 50 years who presented for resection of a primary colorectal neoplasm. Pathologic stage and prior screening were identified retrospectively through chart review and patient response to an anonymous survey. Prior screening was demonstrated in 71 per cent of patients. Colonoscopy was the most commonly used modality. There was a higher percentage of CRC screening at VAMC compared with UVA (80% vs 62%, P < 0.0008). Patients at UVA were more likely screened with colonoscopy, whereas fecal occult blood testing (FOBT) was most common at VAMC (P < 0.0001). Prior CRC screening and cancer stage were inversely related. Ninety-one per cent of patients with benign polyps had been screened prior to diagnosis, compared with 72 per cent of patients with stage I and II cancer and 54 per cent of patients with stage III and IV cancer (P < 0.05). Of patients presenting for surgery, 71 per cent underwent CRC screening. Variability exists in the methods employed for CRC screening. CRC screening facilitates diagnosis at an early stage.  相似文献   
86.
The role of the radiologist in coronary angiography   总被引:1,自引:0,他引:1  
Levin  DC; Adams  DF; Abrams  HL 《Radiology》1977,125(2):313
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The water channel aquaporin-1 (AQP1) is the molecular counterpart of the ultrasmall pore that mediates free water transport during peritoneal dialysis (PD). Proof-of-principle studies performed in rats have shown that treatment with corticosteroids upregulates the expression of AQP1 in the peritoneal capillaries, causing a significant increase in free water transport. Whether such a beneficial effect could be observed in end-stage renal disease patients treated by PD remains unknown. Peritoneal transport parameters were evaluated in three patients on PD, shortly before and after living-donor renal transplantation and treatment with high-dose methylprednisolone (1.0-1.2 g/m(2)). As compared with pre-transplantation values, the post-transplantation test revealed an ~2-fold increase in the sodium sieving and ultrasmall pore ultrafiltration volume, suggesting an effect on AQP1 water channels. In contrast, there was no change in the parameters of small solute transport. The direct involvement of AQP1 in these changes is suggested by the expression of glucocorticoid receptors in the human peritoneum and the presence of conserved glucocorticoid response elements in the promoter of the human AQP1 gene.  相似文献   
90.
Imaging the left ventricular mechanical and hemodynamic response to the stress of exercise may offer early prognosis in select patients with cardiac disease. Here, we demonstrate the feasibility of obtaining simultaneous measurements of longitudinal strain and transvalvular blood velocity during supine bicycle exercise stress in a wide bore magnetic resonance scanner. Combining information from the two datasets, we observe that although the time to peak strain (33.28 ± 1.86 versus 25.7 ± 2.12 as % of R–R interval) and time to peak mitral inflow velocity (44.37 ± 5.21 versus 35.5 ± 4.19 as % of R–R interval) from R‐wave of the QRS complex occurred earlier during stress, the time from peak strain to peak mitral inflow velocity was not statistically different (16.5 ± 3.23 versus 13.4 ± 3.06). Further, the percentage of longitudinal relaxation at peak mitral inflow velocity was higher during stress (63.5 ± 7.72 versus 84.32 ± 6.24). These results suggest that although diastole is shortened, early diastolic filling efficiency is augmented during exercise stress in normal volunteers in an effort to maintain stroke volume. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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