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OBJECTIVES: To determine whether six days recombinant human growth hormone (rhGH) in an abstinent anabolic-androgenic steroid (AAS) group had any cardiovascular and biochemical effects compared with a control group. METHODS: Male subjects (n=48) were randomly divided, using a single blind procedure into two groups: (1) control group (C) n=24, mean+/-SD, age 32+/-11 years; height 1.8+/-0.06m; (2) rhGH using group (0.058IUkg(-1)day(-1)) (GH) n=24, mean+/-SD, age 32+/-9 years; height 1.8+/-0.07m. Physiological responses, anthropometry, arterial pulse wave velocity (APWV), blood pressure (BP), heart rate (HR), peak oxygen uptake (VO(2) peak) and biochemical indices were investigated. RESULTS: Body mass index, fat-free mass index and VO(2) peak significantly increased while body fat significantly decreased within GH (all P<0.017). Insulin like growth factor-I significantly increased within GH (P<0.017) and compared with C (P<0.05). Serum sodium significantly increased (P<0.017) and serum homocysteine, high sensitivity C-reactive protein, thyroid stimulating hormone and tetra-iodothyronine (T(4)), significantly decreased within GH (all P<0.017). T(4) significantly decreased compared with C (P<0.05). Arterial pulse wave velocity, peak and recovery systolic and diastolic BP, significantly decreased compared with C (P<0.05). Resting HR and rate pressure product (RPP) significantly increased compared with C (P<0.05). CONCLUSION: The findings of this study suggest that short term use of rhGH may have beneficial effects on endothelial function and specific inflammatory markers of cardiovascular disease in abstinent AAS users, but may have an adverse effect on the cardiovascular system, as evidenced by the increase in resting RPP.  相似文献   
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AIMS: Syncope in Wolff-Parkinson-White (WPW) syndrome may reveal an arrhythmic event or is not WPW syndrome related. The aim of the study is to evaluate the results of electrophysiological study in WPW syndrome according to the presence or not of syncope and the possible causes of syncope. METHODS AND RESULTS: Among 518 consecutive patients with diagnosis of WPW syndrome, 71 patients, mean age 34.5 +/- 17, presented syncope. Transoesophageal electrophysiological study in control state and after isoproterenol infusion was performed in the out-patient clinic. Atrioventricular re-entrant tachycardia (AVRT) was more frequently induced than in asymptomatic patients (n = 38, 53.5%, P < 0.01), less frequently than in those with tachycardia; atrial fibrillation (AF) and/or antidromic tachycardia (ATD) was induced in 28 patients (39%) more frequently (P < 0.05) than in asymptomatic patients or those with tachycardia. The incidence of high-risk form [rapid conduction over accessory pathway (AP) and AF or ATD induction] was higher in syncope group (n = 18, 25%, P < 0.001) than in asymptomatic subjects (8%) or those with tachycardias (7.5%). Maximal rate conducted over AP was similar in patients with and without syncope, and higher in patients with spontaneous AF, but without syncope. Results were not age-related. CONCLUSION: Tachycardia inducibility was higher in patients with syncope than in the asymptomatic group. The incidence of malignant WPW syndrome was higher in patients with syncope than in asymptomatic or symptomatic population, but the maximal rate conducted over AP was not higher and another mechanism could be also implicated in the mechanism of syncope.  相似文献   
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Meiotic divisions during oogenesis in higher eukaryotes are extremely asymmetric giving rise to one gamete, the oocyte, and two polar bodies. In most species, this asymmetric partitioning relies on the eccentric positioning of meiotic spindles. Recent work performed in mouse and frog oocytes has suggested the involvement of small GTPases, such as Cdc42, Rac and Ran both in the control of spindle organization and positioning. The present review summarizes these findings that shed light on the molecular mechanisms by which small GTPases control asymmetric cell divisions in vertebrate oocytes.  相似文献   
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To meet challenges in terms of throughput and turnaround time, many diagnostic laboratories are shifting from Sanger sequencing to higher throughput next-generation sequencing (NGS) platforms. Bearing in mind that the performance and quality criteria expected from NGS in diagnostic or research settings are strikingly different, we have developed an Ion Torrent''s PGM-based routine diagnostic procedure for BRCA1/2 sequencing. The procedure was first tested on a training set of 62 control samples, and then blindly validated on 77 samples in parallel with our routine technique. The training set was composed of difficult cases, for example, insertions and/or deletions of various sizes, large-scale rearrangements and, obviously, mutations occurring in homopolymer regions. We also compared two bioinformatic solutions in this diagnostic context, an in-house academic pipeline and the commercially available NextGene software (Softgenetics). NextGene analysis provided higher sensitivity, as four previously undetected single-nucleotide variations were found. Regarding specificity, an average of 1.5 confirmatory Sanger sequencings per patient was needed for complete BRCA1/2 screening. Large-scale rearrangements were identified by two distinct analyses, that is, bioinformatics and fragment analysis with electrophoresis profile comparison. Turnaround time was enhanced, as a series of 30 patients were sequenced by one technician, making the results available for the clinician in 10 working days following blood sampling. BRCA1/2 genes are a good model, representative of the difficulties commonly encountered in diagnostic settings, which is why we believe our findings are of interest for the whole community, and the pipeline described can be adapted by any user of PGM for diagnostic purposes.  相似文献   
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