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The availability of a new specific anti 5HT-2 compound, ritanserin (RTS), led us to further investigate the role of serotonin in controlling PRL secretion. The drug was administered to normoprolactinaemic subjects and to patients with differing hyperprolactinaemic conditions. While RTS failed to modify PRL levels in normoprolactinaemic subjects and in patients with PRL-secreting pituitary adenomas, a marked decrease in the hormone was obtained in patients with functional and puerperal hyperprolactinaemia. The lack of effect of RTS in PRL-secreting pituitary adenomas suggests that the reported suppression of PRL by other antiserotoninergic drugs, such as metergoline, is probably due to their concomitant dopaminergic activity.  相似文献   
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Heterotopic pregnancy is the combination of intrauterine and ectopic pregnancy. This potentially fatal condition rarely occurs in spontaneous conception cycles and consequently its diagnosis requires a high index of suspicion. We report a case of heterotopic pregnancy in a 30-year old primipara with no known risk factors who presented with acute abdominal pain due to a spontaneous heterotopic pregnancy. The ectopic pregnancy was resected via laparoscopy. After surgery, the intrauterine pregnancy was uneventful.  相似文献   
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In depressed patients as well as healthy controls, a positive relationship between hippocampal volume and trait anxiety has been reported. This study sought to explore the possible inter-relation between hippocampal volume and trait anxiety further. Magnetic resonance imaging at 7 T was used to measure hippocampal volumes in a rat model of extremes in trait anxiety (experiment 1) and in a Wistar population with normal anxiety-related behavior (experiment 2). In addition to anxiety-related behavior, potentially confounding factors (depression-like, exploratory, and locomotor behavior) were assessed. Experiment 1 globally supported the hypothesis of a positive relationship between hippocampus volume and trait anxiety but did not allow for ruling out possible confounds arising from cosegregation of other behavioral traits. Experiment 2 yielded strong evidence for a negative relationship which was specific for trait anxiety. Thus, the relationship between hippocampal volume and anxiety may be more complex than expected. Interestingly, anxiety-related behavior in experiment 2 had a stronger influence on hippocampal volume than depression-like behavior. In the light of hippocampal volume loss in anxiety disorder and frequent comorbidity of anxiety and depression, this finding suggests that further research into the relationship between anxiety and hippocampal volume may be critical for understanding hippocampal contributions to normal and pathological behavior.  相似文献   
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Our objective was to evaluate the frequency of neoplastic and preneoplastic skin lesions in Parkinson's disease (PD) patients when compared with an aged-matched population. We performed a cross-sectional survey in PD patients and in an age-matched control group. Patients and controls were examined by a movement disorder specialist and a dermatologist. 150 PD patients and 146 controls were included. Thirty-five PD patients (23.3%) presented skin lesions that could be classified as neoplastic or preneoplastic vs. 20 subjects in the control group (13.7%) (OR 95%, CI 1.92 [1.05, 3.51]). However, this difference lost statistical significance when adjusted for gender (recruitment of controls was matched just for age with an over representation of males in the PD group). Twenty-nine PD patients (19%) presented actinic keratosis and basal cell carcinoma was diagnosed in 4 patients (3%). Although nonconclusive, our results are in agreement with previous studies suggesting an increased risk of skin cancer in PD patients. The frequency of actinic keratosis in PD patients and the associated risk to develop melanoma recommends its screening in future epidemiological studies.  相似文献   
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OBJECTIVE: Although an increased distractibility is one of the behavioral criteria of Attention Deficit Hyperactivity Disorder (ADHD), there is little empirical evidence that children with ADHD are in fact more distractible than their normal peers. METHODS: We recorded event-related potentials (ERPs) to distracting novel sounds (novels) and standard sounds, (standards) while children performed a visual two-choice reaction time task. Twenty-five children with ADHD were compared with eighteen normal controls (aged 8-12 years). RESULTS: Children with ADHD showed a larger early P3a (150-250 ms), both in response to the standard and in response to the novel. The late phase of the P3a had a larger amplitude in the ADHD group in the 250-300 ms window compared to the control group, which was only present in response to the novel. Interestingly, the novel reduced the errors of omission in the ADHD group to a greater extent than in the normal control group. CONCLUSIONS: Although children with ADHD show an increased orienting response to novels, this distracting information can enhance their performance temporarily, possibly by increasing their arousal to an optimal level, as indicated by the reduced omission rate. SIGNIFICANCE: These data indicate that distraction is not always distracting in children with ADHD and that distraction can also have beneficial effects.  相似文献   
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