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991.
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With increasing scrutiny of prostate cancer (PCa) diagnosis and treatment, much attention has been given to the morbidity caused by radical prostatectomy (RP) and/or radiotherapy (RT). One of the most common side-effects of either treatment is erectile dysfunction (ED).1 Approximately, 40% of patients will experience ED after RT for PCa. The post-RT ED causes significant patient dissatisfaction with cancer treatment as well as decrease in patient and partner psychosocial function,z To address this issue in patients undergoing RT, Pisansky et al.3 conducted a prospective, randomized, double-blinded, placebo-controlled trial to assess the efficacy of a phosphodiesterase enzyme-5 inhibitor (PDE5i), tadalafil, as a preventive measure for patients undergoing RT for PCa and found no difference in erectile function between the control and treatment groups.  相似文献   
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Background

The efficacy and safety profile of retrograde chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has received limited study. We sought to perform a weighted meta-analysis of the success and complication rates of retrograde CTO PCI.

Methods

We conducted a meta-analysis of 26 studies published between 2006 and April 2013 reporting in-hospital outcomes of retrograde CTO PCI. Data on procedural success, frequency of death, emergent coronary artery bypass graft surgery (CABG), stroke, myocardial infarction (MI), perforation, tamponade, stent thrombosis, major vascular or bleeding events, contrast nephropathy, and radiation skin injury were collected.

Results

A total of 26 studies with 3482 patients and 3493 target CTO lesions were included. Primary retrograde CTO PCI was attempted in 52.4%. Pooled estimates of outcomes were as follows: procedural success 83.3% [95% confidence interval (CI): 79.0% to 87.7%]; death 0.7% (95% CI: 0.5% to 1.2%); urgent CABG 0.7% (95% CI: 0.4% to 1.2%); tamponade 1.4% (95% CI: 1.0% to 2.2%); collateral perforation 6.9% (95% CI: 4.6% to 10.4%); coronary perforation 4.3% (95% CI: 1.2% to 15.4%); donor vessel dissection 2% (95% CI: 0.9% to 4.5%); stroke 0.5% (95% CI: 0.2% to 1.0%); MI 3.1% (95% CI: 0.2% to 5.0%); Q wave MI 0.6% (95% CI: 0.4% to 1.1%); vascular access complications 2% (95% CI: 0.9% to 4.5%); contrast nephropathy 1.8% (95% CI: 0.8% to 3.7%); and wire fracture and equipment entrapment 1.2% (95% CI: 0.6% to 2.5%).

Conclusions

Retrograde CTO PCI is associated with high procedural success rate and acceptable risk for procedural complications.  相似文献   
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Background

Hepatocellular carcinoma (HCC) is a leading cancer-related cause of death worldwide. There are widespread global differences in HCC risk. Although the impact of geographic prevalence of specific causes of chronic liver disease on HCC is recognized, the contribution of the underlying genetic architecture to the risk of HCC remains undefined. Our aim was to characterize evolutionary trends in genetic susceptibility to HCC.

Methods

We examined the genetic risk associated with HCC risk alleles identified from genome-wide association studies and correlated these with geographic location and temporal and spatial patterns of human migration.

Results

A moderate increase in differentiation was noted for rs2596542 (F st = 0.106) and rs17401966 (F st = 0.116), single nucleotide polymorphisms (SNPs) associated with an increased risk of HCC in patients with chronic HCV and HBV, respectively. Both of these SNPs show a recent increase in allelic frequency with the most recent human migrations into East Asia, Oceania and the Americas. In contrast another SNP associated with an increased risk of HCC, rs9275572, showed a lack of differentiation (F st = 0.09) with stable allelic expression across populations. The genetic risk score for HCC, based on the allelic frequency and risk odds ratio of five SNPs associated with increased risk of HCC, was greatest in populations from Africa and decreased with subsequent migration into Europe and Asia. However, a major increase was noted with the most recent migrations into Oceania and the Americas.

Conclusions

There are differences in directional differentiation of HCC risk alleles across human populations that can contribute to population-based differences in HCC prevalence.  相似文献   
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