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21.

Aim

Extended liver resection has increased during the last decades. However, hepatic hemodynamic changes after resection and the consequent complications like post hepatectomy liver failure are still a challenging issue. The aim of this study was to systematically evaluate the role of stepwise liver resection on hepatic hemodynamic changes.

Methods

To evaluate this effect we performed 25, 50, and 75 % sequential liver resections in 10 pigs. Before and after each resection, the hepatic artery flow and portal vein flow in relation to the remnant liver volume (RLV) as well as hepatic vascular pressures were measured and compared between the groups.

Results

Following sequential liver resection, the hepatic artery flow /100 g decreases and the portal vein flow increases up to 17 and 167 % following extended liver resection (75 %), respectively. Also, during stepwise liver resection, the portal vein pressure increases gradually up to 33 % following extended hepatectomy (75 %).

Conclusion

Sequential decrease in the RLV decreases the hepatic artery flow /100 g and increases the portal vein flow /100 g and portal vein pressure. As the consequence, the liver goes under more poor-oxygenated blood supply and higher pressure. This may be one of the most important mechanisms of the post hepatectomy liver failure in case of extended liver resection.
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Social vigilance is a behavioral strategy commonly used in adverse or changing social environments. In animals, a combination of avoidance and vigilance allows an individual to evade potentially dangerous confrontations while monitoring the social environment to identify favorable changes. However, prolonged use of this behavioral strategy in humans is associated with increased risk of anxiety disorders, a major burden for human health. Elucidating the mechanisms of social vigilance in animals could provide important clues for new treatment strategies for social anxiety. Importantly, during adolescence the prevalence of social anxiety increases significantly. We hypothesize that many of the actions typically characterized as anxiety behaviors begin to emerge during this time as strategies for navigating more complex social structures. Here, we consider how the social environment and the pubertal transition shape neural circuits that modulate social vigilance, focusing on the bed nucleus of the stria terminalis and prefrontal cortex. The emergence of gonadal hormone secretion during adolescence has important effects on the function and structure of these circuits, and may play a role in the emergence of a notable sex difference in anxiety rates across adolescence. However, the significance of these changes in the context of anxiety is still uncertain, as not enough studies are sufficiently powered to evaluate sex as a biological variable. We conclude that greater integration between human and animal models will aid the development of more effective strategies for treating social anxiety.  相似文献   
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Capsule endoscopy (CE) revolutionized the small bowel examination. We emphasize the role of CE in suspected Crohn's disease, studying 24 investigations performed in the Institute of Gastroenterology and Hepatology. The global diagnostic yield was 54%, the specific diagnostic yield for Crohn's disease was 37.5%, the specificity was 100% and the retention rate was 4.1%. For maximum accuracy and efficiency, unitary administration and diagnostic criteria are needed, and for minimising the risk of complications, specific prior investigations would be suitable.  相似文献   
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Background: Ropivacaine may be useful for intravenous regional anesthesia, but its anesthetic effectiveness and toxicity have not been evaluated.

Methods: Two doses of ropivacaine (1.2 and 1.8 mg/kg) and one dose of lidocaine (3 mg/kg) were compared for intravenous regional anesthesia in 15 volunteers. An arm tourniquet was inflated for 30 min after injection and then deflated in two cycles. Sensory block was measured by response to touch, cold, pinprick, and transcutaneous electric stimulation, and motor function was measured by hand grip strength and muscle power. Median, ulnar, radial, and musculocutaneous nerve functions were tested before local anesthetic injection and then at 5-min intervals until blocks resolved. The plasma ropivacaine and lidocaine concentrations were determined from arterial and venous blood samples drawn from the unanesthetized arm.

Results: Sensory and motor blocks were complete within 25 min and 30 min, respectively, in all three treatment groups. However, recovery of sensory and motor block after tourniquet release was slowest in the high-dose ropivacaine group. Anesthesia to pinprick and transcutaneous electric stimulation was sustained in all the volunteers in the high-dose ropivacaine group for 55 min and 85 min, respectively, whereas complete recovery was observed in the lidocaine group (P = 0.008) and partial recovery in the low-dose ropivacaine group (P < 0.05) during the same period. Motor block also was sustained in the high-dose ropivacaine group for 70 min, which was significantly longer than in the lidocaine group (P < 0.05). All volunteers (five of five) given lidocaine and one volunteer given high-dose ropivacaine reported light-headedness and hearing disturbance during tourniquet release when the arterial plasma lidocaine and ropivacaine concentrations were 4.7 +/- 2.1 [micro sign]g/ml (mean) and 2.7 [micro sign]/ml, respectively.  相似文献   

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THE AIM OF THIS STUDY: Is to identify two severe complications after catheterism of nasolacrimal duct. A boy, 9 months old, was treated in Clinica I Oftalmologie la?i for presptal cellulitis after catheterism of nasolacrimal duct which was performed in other Eye clinic, without general anesthesia. Also, this child presented the rupture of punctal and inferior canalicular duct. CONCLUSION: Catheterism of nasolacrimal duct must be performed by ophthalmopediatric doctors with experience, under general anesthesia, to prevent complications.  相似文献   
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We have investigated the cellular and serum CK18 in 26 non-treated primary ductal invasive breast carcinomas. The soluble CK18 (TPS) was detected by chemiluminescent assay, and the cellular CK18 and PCNA expression by immunocytochemistry. Flow-cytometry was used to estimate the amount of DNA in malignant cells. There was a significant correlation between soluble CK18 and the pre-menopausal status (p < 0.05), characterized in our group by a PCNA estimated low proliferation index. We have also found a significant correlation between soluble CK18 and the DNA index (p < 0.01). The intracellular CK18 has correlated with the PCNA expression (p < 0.05), while no correlation could be found between cellular and serum CK18. The values of soluble CK18 may offer information about the treatment-induced cell death, if monitored, while isolated measurements should be interpreted cautiously. Elevated levels of serum CK18 in non-treated carcinomas may rather reflect a high tumor turn-over or perhaps a more intensive tumor cell killing.  相似文献   
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