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OBJECTIVE: Although various brain regions have been shown to respond to the presentation of visual sexual stimuli (VSS), whether these regions are specifically mediating sexual arousal or whether they mediate general emotional or motivational arousal is unknown. To clarify this issue, our purpose was to map the regions where the response to VSS was related to plasma testosterone. Specific objectives were (i) to identify regions that respond differentially to VSS in untreated hypogonadal patients compared with healthy controls and (ii) to identify in hypogonadal patients the regions that respond differentially to VSS as a function of therapeutically induced increased testosterone levels. METHOD: In nine male hypogonadal patients, in the same patients under treatment, and in eight healthy males, we used Positron Emission Tomography to investigate responses of regional cerebral blood flow to VSS. Statistical Parametric Mapping was used to locate regions that demonstrated a differential response. RESULTS: Regions responding differentially both in untreated patients compared with controls and in untreated patients compared with themselves under treatment were the right orbitofrontal cortex, insula and claustrum, where the activation was higher in controls than in untreated patients and where activation increased under treatment, and the left inferior frontal gyrus, that demonstrated a deactivation only in controls and in patients under treatment. That these responses appear to depend on testosterone indicates that these regions mediate sexual arousal and not only a process of general emotional or motivational arousal.  相似文献   
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L. Costes  M. Ducreux  V. Boige 《Oncologie》2008,10(3):191-196
Systemic cytotoxic treatments provide marginal benefit in unresectable or metastatic HCC. With the arrival of molecularly targeted agents, there has been renewed interest in developing novel systemic treatments for HCC. For the first time, results of a phase III randomized, placebo-controlled trial were recently presented in which sorafenib demonstrated improved survival in patients with advanced HCC. Therefore, sorafenib is now the new standard for the first-line treatment of advanced HCC. The identification of predictive factors and the search for new molecules remain major challenges for this poor prognostic disease.  相似文献   
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Task-independent semantic activation for numbers and animals   总被引:1,自引:0,他引:1  
Semantic processing of numbers and animals was contrasted with PET in two different tasks (comparison and classification) to test the hypothesis that knowledge about numbers is associated with increased activation in the parietal cortices, regardless of the semantic task (i.e. Classification: is seven odd? Comparison: is seven larger than 5?). By contrast, processing animal names was expected to produce activation in inferior temporal areas. Task-independent activation was observed in the left and right intraparietal sulci for number names, whereas task-independent activation of the left inferior temporal gyrus was found for animal names. No significant interaction between the category (numbers or animals) and the semantic task (comparison or classification) was observed. Accordingly, the IPS activation classically observed during numerical processing appears to be related to category-specific semantic knowledge about numbers. Likewise, the activation of the inferior temporal gyrus associated with the processing of animal names is probably related to category-specific knowledge about animals. The results strongly support the hypothesis that different brain regions are important for storing conceptual knowledge about different semantic categories.  相似文献   
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Abstract Aims Autonomic nervous system activity decreases continuously with age and appears to be a powerful predictor of disease and death. Attempts are thus made to reactivate autonomic drive with the intent of improving health. Methods We assessed maximal oxygen consumption (VO2max), auto- nomic nervous system activity by heart rate variability (HRV) analysis and spontaneous cardiac baroreflex activity (SBR) in eleven elderly men (73.5±4.2 years) before and after a 14-week program of intensive cycloergometer interval training. The standard HRV indices were calculated using time domain (mean RR, PNN50, RMSSD, SDNN, SDANN and SDNNIDX), and Fourier transform (total power, ULF,VLF, LF, LFnu, HF, HFnu and LF/HF) analyses of 24-hour, daytime and nighttime Holter recordings. The SBR was calculated from 15-minute recordings of spontaneous blood pressure and RR interval variations using the sequence (slope, slSBR) and cross-spectral (SBRHF and SBRLF) methods. Results After the training period,VO2max increased by 18.6 % (26.8±4.4 to 31.8±5.2 ml · kg–1 · min–1, p<0.01). The nocturnal parasympathetic indices of HRV increased (PNN50: 3.05±2.21 to 5.00±2.87%, RMSSD: 29.1±7.6 to 38.8±10.9 ms, HF: 117±54 to 194±116 ms2/Hz, all p<0.05) as did the SBR indices (slSBR: 7.0±1.8 to 9.8±2.1 ms·mmHg–1, p<0.01; SBRHF: 6.9±2.2 to 10.5±3.7 ms ·mmHg–1, p<0.05; SBRLF: 5.3±2.3 to 6.9±3.1 ms ·mmHg–1, p=0.22). Conclusion Intensive endurance training in elderly men enhanced parasympathetic parameters of HRV and, interestingly, of SBR. Physiological mechanisms and long-term clinical effects on health status should be further investigated.  相似文献   
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PURPOSE: Monitoring physical performance is of major importance in competitive sports. Indices commonly used, like resting heart rate, VO2max, and hormones, cannot be easily used because of difficulties in routine use, of variations too small to be reliable, or of technical challenges in acquiring the data. METHODS: We chose to assess autonomic nervous system activity using heart rate variability in seven middle-distance runners, aged 24.6 +/- 4.8 yr, during their usual training cycle composed of 3 wk of heavy training periods, followed by a relative resting week. The electrocardiogram was recorded overnight twice a week and temporal and frequency indices of heart rate variability, using Fourier and Wavelet transforms, were calculated. Daily training loads and fatigue sensations were estimated with a questionnaire. Similar recordings were performed in a sedentary control group. RESULTS: The results demonstrated a significant and progressive decrease in parasympathetic indices of up to -41% (P < 0.05) during the 3 wk of heavy training, followed by a significant increase during the relative resting week of up to +46% (P < 0.05). The indices of sympathetic activity followed the opposite trend, first up to +31% and then -24% (P < 0.05), respectively. The percentage increasing mean nocturnal heart rate variation remained below 12% (P < 0.05). There was no significant variation in the control group. CONCLUSION: This study confirmed that heavy training shifted the cardiac autonomic balance toward a predominance of the sympathetic over the parasympathetic drive. When recorded during the night, heart rate variability appeared to be a better tool than resting heart rate to evaluate cumulated physical fatigue, as it magnified the induced changes in autonomic nervous system activity. These results could be of interest for optimizing individual training profiles.  相似文献   
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