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991.
Early-onset colorectal cancer (EOCRC) has seen an alarming rise worldwide over the past two decades. The reason for this global trend is poorly understood. EOCRC appears to have its own unique clinical and molecular features when compared with late-onset colorectal cancer. Younger patients appear to have more distal or rectal disease, a more advanced stage of disease at presentation, and more unfavorable histological features. Identifying risk factors for EOCRC is the first step in mitigating the rising burden of this disease. Here we summarize several noteworthy biological factors and environmental exposures that are postulated to be responsible culprits. This can hopefully translate in clinical practice to the development of better risk stratification tool for identifying high-risk individuals for early colorectal cancer screening, and identifying areas needed for further research to curb this rising trend. 相似文献
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Daniel Ebrahimi‐Fakhari Sascha Meyer Thomas Vogt Claudia Pföhler Cornelia Sigrid Lissi Müller 《Journal der Deutschen Dermatologischen Gesellschaft》2017,15(7):695-700
Tuberous sclerosis complex (TSC) is a genetic multisystem disorder with prominent skin involvement that frequently occurs in early childhood. Dermatologic manifestations include facial angiofibromas, hypomelanotic macules, fibrous cephalic plaques, shagreen patches, and ungual fibromas. The International TSC Consensus Conference in 2012 provided guidelines for standardized baseline evaluation and follow‐up. Detailed clinical dermatological evaluation at the time of diagnosis and annual skin examination is recommended for both pediatric and adult populations. The onset of dermatological manifestations is clearly age‐related. However, dermatologists also have to assess for clinical manifestations beyond their own specialty. With advances in genetics and the advent of mTORC1 inhibitors, new specific therapeutic options have become available for TSC patients with skin manifestations. Early intervention is commonly recommended for symptomatic, rapidly evolving, disfiguring, or debilitating lesions. The consensus guidelines recommend “treatment as appropriate for the lesion and clinical context” and suggest the use of surgical excision, laser therapy, or topical mTORC1 inhibitors. Topical mTORC1 inhibitors present a useful option for TSC‐associated skin lesions, particularly in medically complex patients. They may prevent or reduce the risks of subsequent surgeries and permanent scarring. 相似文献
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Effects of TIPS on liver perfusion measured by dynamic CT 总被引:18,自引:0,他引:18
Weidekamm C Cejna M Kramer L Peck-Radosavljevic M Bader TR 《AJR. American journal of roentgenology》2005,184(2):505-510
OBJECTIVE: Our aim was to measure the arterial, portal venous, and total perfusion of the liver parenchyma with dynamic, single-section CT in patients with liver cirrhosis before and after transjugular intrahepatic portosystemic shunt (TIPS) placement and to compare the results with normal values. SUBJECTS AND METHODS: Perfusion of the liver parenchyma was measured in 24 healthy volunteers and 41 patients with liver cirrhosis using dynamic single-section CT. Seventeen patients underwent TIPS placement, and CT measurements were repeated within 7 days. CT scans were obtained at a single level comprising the liver, spleen, aorta, and portal vein. Scans were obtained over a period of 88 sec (one baseline scan followed by 16 scans every 2 sec and eight scans every 7 sec) beginning with the injection of a contrast agent bolus (40 mL at 10 mL/sec). Parenchymal and vascular contrast enhancement was measured with regions of interest, and time-density curves were obtained. These data were processed with a pharmaco-dynamic fitting program (TopFit), and the arterial and portal venous component and the total perfusion of the hepatic parenchyma were calculated (milliliters of perfusion per minute per 100 mL of tissue). RESULTS: Mean normal values for hepatic arterial, portal venous, and total perfusion were 20, 102, and 122 mL/min per 100 mL, respectively. In patients with cirrhosis before TIPS, mean hepatic arterial, portal venous, and total perfusion was 28, 63, and 91 mL/min per 100 mL, respectively, which was statistically significant for all values (p <0.05). After TIPS, hepatic perfusion increased to a mean value of 48, 65, 113 mL/min per 100 mL for arterial (p <0.01), portal venous, and total (p=0.011) perfusion, respectively. CONCLUSION: In patients with cirrhosis, the hepatic arterial perfusion increased, whereas portal venous and total perfusion decreased compared with that of healthy volunteers. TIPS placement caused a statistically significant increase of the hepatic arterial and total hepatic perfusion. The portal venous parenchymal perfusion remained unchanged. 相似文献