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In this paper we analyze a fibrosis scoring method based on measurement of the fibrillar collagen area from second harmonic generation (SHG) microscopy images of unstained histological slices from human liver biopsies. The study is conducted on a cohort of one hundred chronic hepatitis C patients with intermediate to strong Metavir and Ishak stages of liver fibrosis. We highlight a key parameter of our scoring method to discriminate between high and low fibrosis stages. Moreover, according to the intensity histograms of the SHG images and simple mathematical arguments, we show that our area-based method is equivalent to an intensity-based method, despite saturation of the images. Finally we propose an improvement of our scoring method using very simple image processing tools.OCIS codes: (180.4315) Nonlinear microscopy, (170.1610) Clinical applications, (170.3880) Medical and biological imaging, (170.4580) Optical diagnostics for medicine, (110.2960) Image analysis  相似文献   
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Percutaneous transseptal left atrial (LA) access is increasingly becoming a routine procedure in the electrophysiology and cardiac catheterisation laboratories. Our aim was to review an unselected large series of this procedure performed over a period of five years. We clinically characterised difficult cases and presented a method of safe and expeditious LA access. Overall, 543 transseptal punctures were performed. Of those, 10 were classified as difficult, with failure to access the LA in three or more attempts. In all 10 cases, surgical electrocautery was successfully used to facilitate needle puncture of the septum. All patients subsequently underwent an uncomplicated procedure. In conclusion, we describe a method to trouble-shoot the difficult transseptal access procedure, outlining the clinical characteristics, echocardiographic features and special precautions that need to be considered when utilising this method.  相似文献   
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Objective: There is a promising perspective regarding the potential effect of resveratrol in preventing and treating metabolic disturbances similar to that of calorie restriction. The aim of this study was to evaluate the effects of calorie-restricted (CR) diet on metabolic parameters and then to investigate whether resveratrol supplementation has beneficial effects similar to CR diet in patients with nonalcoholic fatty liver disease (NAFLD).

Methods: This randomized controlled clinical trial was conducted in 90 patients with NAFLD (males and females) aged 20 to 60 years with body mass index (BMI) ranging from 25 to 35 kg/m2. Participants were assigned to one of three intervention groups as follows: The CR diet group (n = 30) received a prescribed low-calorie diet, the resveratrol group (n = 30) received 600 mg pure trans-resveratrol (2 × 300 mg) daily, and the placebo group (n = 30) received placebo capsules (2 × 300 mg) daily for 12 weeks. Fasting blood samples, anthropometric measurements, and dietary intake and physical activity data were collected for all participants at baseline and at the end of the trial.

Results: CR diet significantly reduced weight (by 4.5%); BMI; waist circumference; waist-to-hip ratio; and serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lipid profiles in participants compared to resveratrol and placebo (all p < 0.05). Significant reductions in weight (by 1.1%) and BMI were found in the resveratrol group compared to the placebo group (p < 0.05). ALT, AST, and lipid profiles did not change significantly in the resveratrol group (all p > 0.05). No significant changes were seen in hepatic steatosis grade, serum glycemic parameters, and high-density lipoprotein cholesterol and sirtuin-1 levels in any group (all p > 0.05).

Conclusions: CR diet with moderate weight loss has favorable effects on NAFLD, and resveratrol supplementation induced weight loss but failed to mimic other aspects of CR diet. Future studies are warranted to evaluate the long-term and dose-dependent effects of resveratrol on metabolic diseases.  相似文献   

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Lasers in Medical Science - The combination of multiple therapeutic and diagnostic functions is fast becoming a key feature in the area of clinical oncology. The advent of nanotechnology promises...  相似文献   
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Background

Successful reperfusion after acute ST-elevation myocardial infarction improves prognosis. Among the different electrocardiographic markers of reperfusion, sum ST resolution is considered the hallmark of reperfusion, but is cumbersome to use.

Methods

To assess the usefulness of a single lead ST resolution at 90 minutes after fibrinolysis compared with the sum ST resolution in predicting Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow, we used prospectively collected data from the Limitation of Myocardial Injury Following Thrombolysis in Acute Myocardial Infarction (LIMIT-AMI) study. All patients had electrocardiograms recorded at presentation and 90 minutes and a coronary angiogram 90 minutes after fibrinolysis.

Results

Infarction artery patency was assessed in 238 patients with 4 different ST resolution criteria: single lead ST resolution ≥50% and ≥70% and sum ST resolution ≥50% and ≥70%. The most sensitive criteria for TIMI grade 3 flow was single lead ST resolution ≥50% (sensitivity rate, 70%; specificity rate, 54%), whereas sum ST resolution ≥70% was most the specific criteria (sensitivity rate, 45%; specificity rate, 79%). The proportion of patients with TIMI grade 3 flow was similar in all 4 ST resolution groups (P = .84). Pre-discharge infarction size and ejection fraction were also similar. No single lead or sum lead measure of ST resolution was significantly associated with an increased risk of death, heart failure, or reinfarction.

Conclusion

We propose that single lead ST-resolution ≥50% as an optimal electrocardiographic indicator for successful reperfusion 90 minutes after fibrinolysis. This simple electrocardiographic measure should be combined with bedside clinical and hemodynamic assessment to optimize decision making after fibrinolysis.  相似文献   
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