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101.
The management of intraductal papillary mucinous neoplasms(IPMN) is presently evolving as a result of the improved understanding of the natural history and biological behavior of the different pancreatic cystic neoplasms; and better preoperative diagnosis of these neoplasms due to advancement in preoperative diagnostic tools. International consensus guidelines for the management of IPMN were first formulated in 2006 and subsequently revised in 2012. Both these guidelines were constructed based on expert opinion and not on robust clinical data. The main limitation of the original Sendai guidelines was that it had a low positive predictive value resulting in many benign neoplasms being resected. Hence,these guidelines were revised in 2012. However,although the updated guidelines resulted in an improvement in the positive predictive value over the Sendai Guidelines,the results of several studies validating these guidelines demonstrated that its positive predictive value remained low. Furthermore,although both guidelines were associated with high negative predictive values,several investigators have demonstrated that some malignant IPMNs may be missed. Finally,it is imperative to emphasize that major considerations when managing a patient with IPMN including the patient's surgical risk,life-expectancy and even cost of investigations are not taken into account in current guidelines. The management of a patient with IPMN should be individualized and tailored according to a patient's risk benefit profile for resection vs surveillance.  相似文献   
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The kinetics of serum hepatitis B surface antigen (HBsAg) during the natural history of hepatitis B virus (HBV) infection has been studied, but the factors affecting them remain unclear. We aimed to investigate the factors affecting HBsAg titres, using data from multicentre, large‐sized clinical trials in China. The baseline data of 1795 patients in 3 multicentre trials were studied, and the patients were classified into 3 groups: hepatitis B early antigen (HBeAg)‐positive chronic HBV infection (n = 588), HBeAg‐positive chronic hepatitis B (n = 596), and HBeAg‐negative chronic hepatitis B (n = 611). HBsAg titres in the different phases were compared, and multiple linear progression analyses were performed to investigate the implicated factors. HBsAg titres varied significantly in different phases (= .000), with the highest (4.60 log10 IU/mL [10%‐90% confidence interval: 3.52 log10 IU/mL‐4.99 log10 IU/mL]) in patients with HBeAg‐positive chronic HBV infection. In all phases, age and HBV DNA were correlated with serum HBsAg level. In HBeAg‐positive chronic hepatitis B patients, a negative correlation between HBsAg titres and fibrosis stage was observed. Alanine amonitransferase or necroinflammatory activity was also correlated with HBsAg titres in HBeAg‐negative chronic hepatitis B patients. In conclusion, decreased HBsAg titres may be associated with advancing fibrosis in HBeAg‐positive chronic hepatitis B patients or increased necroinflammation in those with HBeAg‐negative chronic hepatitis B. Our findings may help clinicians better understand the kinetics of HBsAg and provide useful insights into the management of this disease.  相似文献   
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Functional network activity alterations are one of the earliest hallmarks of Alzheimer’s disease (AD), detected prior to amyloidosis and tauopathy. Better understanding the neuronal underpinnings of such network alterations could offer mechanistic insight into AD progression. Here, we examined a mouse model (3xTgAD mice) recapitulating this early AD stage. We found resting functional connectivity loss within ventral networks, including the entorhinal cortex, aligning with the spatial distribution of tauopathy reported in humans. Unexpectedly, in contrast to decreased connectivity at rest, 3xTgAD mice show enhanced fMRI signal within several projection areas following optogenetic activation of the entorhinal cortex. We corroborate this finding by demonstrating neuronal facilitation within ventral networks and synaptic hyperexcitability in projection targets. 3xTgAD mice, thus, reveal a dichotomic hypo-connected:resting versus hyper-responsive:active phenotype. This strong homotopy between the areas affected supports the translatability of this pathophysiological model to tau-related, early-AD deficits in humans.  相似文献   
105.
Monatsschrift Kinderheilkunde - Fehlstellungen der Hüfte sind bei Kindern und Jugendlichen gut an einem hinkenden Gang, an der Rumpfasymmetrie im Stand sowie an einem seitendifferenten aktiven...  相似文献   
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The shoulder: adaptive motion correction of MR images   总被引:2,自引:0,他引:2  
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108.
Jaffe  MH; White  SJ; Silver  TM; Heidelberger  KP 《Radiology》1981,140(1):147-152
The gray-scale ultrasonic features of Wilms tumor are reported with pathologic comparison. The most consistent ultrasonic features are large size, sharp margination, and echogenic heterogeneity. The frequently observed anechoic areas correlated with hemorrhage and necrosis. A rare case of mesoblastic nephroma is included for comparison. Pitfalls in diagnosis are discussed.  相似文献   
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