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BackgroundReactive oxygen species (ROS) play a fundamental role in angiogenesis, and in turn, angiogenic growth factors also affect ROS. Angiogenesis and ROS are intricately involved in vascular deterioration. Since black populations are known to have elevated oxidative stress and hypertension, we determined whether relationships exist between angiogenic growth factors and serum peroxides in Africans and Caucasians and evaluated the relationships with cardiovascular measurements.MethodsWe measured vascular endothelial growth factor-A (VEGF), angiopoietin 2 (Ang-2), and serum peroxides in Africans (N = 262) and Caucasians (N = 364) aged 20 to 70 years.ResultsAfricans displayed higher blood pressure, serum peroxide levels, VEGF, and Ang-2 (all P ≤ .002) than similarly aged Caucasians (P = .44). In multivariable adjusted analyses, Ang-2 was independently associated with serum peroxides in African men (R2 = 0.31; β = 0.21; P = .014) and women (R2 = 0.09; β = 0.22; P = .025); and VEGF with serum peroxides in African men (R2 = 0.12; β = 0.24; P = .014), with no statistically significant associations in Caucasians. Cardiovascular measurements did not associate with serum peroxides or angiogenic factors in any subgroup.ConclusionsSignificant independent relationships exist between angiogenic growth factors and serum peroxides only in Africans who also displayed an unfavorable cardiovascular profile when compared with Caucasians. These results suggest that interplay between ROS and angiogenesis occur in African individuals that may form part of the mechanisms involved in vascular deterioration.  相似文献   
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Gastroesophageal reflux disease(GERD) is a frequently encountered disorder. Obesity is an important risk factor for GERD, and there are several pathophysiologic mechanisms linking the two conditions. For obese patients with GERD, much of the treatment effort is focused on weight loss and its consistent benefit to symptoms, while there is a relative lack of evidence regarding outcomes after novel or even standard medical therapy is offered to this population. Physicians are hesitant to recommend operative anti-reflux therapy to obese patients due to the potentially higher risks and decreased efficacy, and these patients instead are often considered for bariatric surgery. Bariatric surgical approaches are broadening, and each technique has emerging evidence regarding its effect on both the risk and outcome of GERD. Furthermore, combined antireflux and bariatric options are now being offered to obese patients with GERD. However, currently Rouxen-Y gastric bypass remains the most effective surgical treatment option in this population, due to its consistent benefits in both weight loss and GERD itself. This article aims to review the impact of both conservative and aggressive approaches of obesity treatment on GERD.  相似文献   
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Pepducins containing a fatty acid linked to an amino acid sequence derived from cytosolic parts of a G-protein-coupled receptor (GPCR) constitute a new group of lipopeptide tools in GPCR studies. Pepducins corresponding to the third intracellular loop of formyl peptide receptor 2 (FPR2) activate human neutrophils, and we show here that, in addition, these allosteric modulators of receptor activity also kill bacteria. The functional dualism of FPR2 pepducins could potentially be explored as a novel class of antibacterial drugs with immunomodulatory properties.  相似文献   
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Introduction  

Preconception diagnosis requires first polar body biopsy. When the hole in the zona pellucida is made with a laser beam, heat propagation could, like the biopsy itself, be deleterious. Our aim was to evaluate the effect of this technique on human in vitro matured oocyte and embryo development.  相似文献   
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OBJECTIVE: Existing literature indicates that the mortality rate with each variceal bleeding episode is 30-50%. Over the past 2 decades, there have been significant developments in the management of variceal bleeding. The effect of these developments on the natural history of variceal bleeding is unclear. Therefore, a retrospective, multicenter study was conducted to define the outcomes of variceal bleeding and to describe the patterns of current practice in the management of variceal bleeding. METHODS: All patients with documented variceal bleeding hospitalized at four large county hospitals from January 1, 1997, to June 30, 2000, were included. Study outcomes were in-hospital, 6-wk, and overall mortality, rate of rebleeding, transfusion requirement, and length of stay. After discharge, patients were followed until death or study closure date, on June 30, 2000. RESULTS: A total of 231 subjects were included, and their in-hospital, 6-wk, and overall mortality rates were 14.2%, 17.5%, and 33.5%, respectively. The frequency of rebleeding during follow-up was 29%. Median length of total hospital stay was 8 days (0-34 days). Median number of packed red cell units transfused was 4 U (0-60 U). Upper endoscopy was performed in 95% of patients within 24 h, and endoscopic therapy was done in all but eight patients (ligation 64%, sclerotherapy 33%). Octreotide was administered in 74% of the patients. Portasystemic shunts were performed in 7.5% of the patients for controlling acute variceal bleeding. CONCLUSIONS: The mortality rate after variceal bleeding in this study was substantially lower than previously reported. This suggests that advances made in the management of variceal bleeding have improved outcomes after variceal bleeding.  相似文献   
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The aim of this work was to specify the timecourse of response to interferon (IFN) of hepatitis Gvirus (HGV) and hepatitis C virus (HCV) in coinfectedindividuals. A group of 33 patients, undergoing 12 months of IFN therapy for chronic hepatitis C,was screened for the presence of both HGV and HCV RNAsto select seven coinfected patients. Spontaneousrecovery from HGV infection was excluded through the detection of antibodies to the envelope-2protein of HGV and HCV isolates were genotyped. Withinthree months of treatment, we found that HGV RNA wastransiently cleared in 6/7 patients, but the rate of long-term favorable response was very low(1/7). In addition, considering the same individualsseparately, it was shown that HGV and HCV responded toIFN with different kinetics in 5/7 patients. Takentogether, these results underscore the importance of thevirological basis of the resistance to IFNtreatment.  相似文献   
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