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21.
Most studies on visual perception of human beings have focused on perception of faces. However, bodies are another important visual element, which help us to identify a member of our species in the visual scene. In order to study whether similar configural information processing is used in body and face perception, we recorded high-density even-related potentials (ERPs) to normal and distorted faces and bodies in adults and 3-month-old infants. In adults, the N1 responses evoked by bodies and faces were similar in amplitude but differed slightly in latency. The voltage topography of N1 also differed in concordance with fMRI data showing that two distinct areas are involved in face and body perception. Distortion affected ERPs to faces and bodies similarly from N1 on, although the effect was significant earlier for bodies than for faces. These results suggest that fast processing of configural information is not specific to faces but it also occurs for bodies. In 3-month-old infants, distortion decreased the amplitude of P400 around 450 msec, showing no interaction with image category. This result demonstrates that infants are not only able to recognize the normal configuration of faces, but also that of bodies. This could either be related to an innate knowledge of this particular type of biological object, or to fast learning through intense exposure during the first months of life. 相似文献
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We studied adverse reactions to immunisation in 541 individuals receiving simultaneous pneumococcal and influenza vaccination, and in 320 recipients of pneumococcal vaccine alone. Five days after immunisation, the participants completed a questionnaire covering systemic and local reactions to vaccination. Adverse effects were rated as mild if they did not interfere with the participant's daily activities, and moderate or serious if they moderately or markedly restricted these activities. There were no differences between the groups regarding general malaise, headache, myalgias and elevated body temperature. Redness at the injection site, but not soreness or swelling, occurred more frequently in individuals immunised simultaneously with both vaccines. Except for fever and local swelling, adverse reactions were significantly more frequent in women than in men in study groups. The rate of adverse reactions was higher in individuals less then 65 years of age than in older participants. Local reactions were reported by 358 (41.6%) participants, but they were mild and soon subsided. No serious reactions were reported. pneumococcal and influenza vaccine can be safely administered simultaneously. 相似文献
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The purpose of this study was to learn about the frequency of sexual disorders in young males who later become substance abusers. We interviewed 228 men treated in 10 drug centers for substance abuse. The questionnaire that we used was designed to assess the onset of erectile dysfunction (ED) or of premature ejaculation (PE). Only those subjects who became substance users between the ages of 17 to 29 were taken into consideration. Of the 228 subjects recruited, only 130 met the inclusion criteria (mean age 33). These male patients had a prevalence of ED of 20.3% (cl 99% 12.3-31.2), whereas the prevalence of ED of age-matched males in the general population is 2.1% (cl 99% 0.36-5.46; p < 0.000001). The prevalence of PE in the sample prior to drug use was 37.5%. Sexual desire was in the normal range in nearly all subjects. The prevalence of ED in the men of our sample is higher than in age-matched individuals of the general population. These data suggest a new hypothesis: sexual disorders or the conviction that one has a sexual problem is a possible risk factor among men for drug abuse and addiction. 相似文献
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OBJECTIVE: While it is technically feasible to conduct migraine research on the Internet, can one be sure that the subjects who participate actually have the disorder? We examined this issue in 109 sequential subjects in an Internet study of migraineurs' symptoms. BACKGROUND: The increasing use of the Internet by the US population provides an opportunity for using this medium in clinical research, but, to be useful, the results of such research must be valid and generalizable. METHODS: Using postings to Internet newsgroups of migraineurs, we recruited subjects to a migraine research site. We examined reported symptoms by comparing them with the International Headache Society's criteria for diagnosis of migraine and by subjective review by a neurologist. We also attempted to contact the subject's primary care physicians to confirm their diagnosis. RESULTS: We found considerable evidence for the validity of the participants' self-reported diagnoses. Most subjects with professed migraine reported quality of pain (97%) and associated symptoms (92%) consistent with that diagnosis, and review of their symptoms and questionnaire responses by the neurologist suggested that almost all subjects (97%) had migraine. Personal physicians confirmed a diagnosis of migraine in 90% of consenting subjects (n=49). CONCLUSIONS: The validity of self-reported diagnosis of migraine does not appear to be an obstacle to conducting research in subject populations on the Internet. 相似文献
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Teodora Ribarska Klaus-Marius Bastian Annemarie Koch Wolfgang A Schulz 《Asian journal of andrology》2012,14(3):436-450
Epigenetic dysregulation comprising DNA hypermethylation and hypomethylation, enhancer of zeste homologue 2 (EZH2) overexpression and altered patterns of histone modifications is associated with the progression of prostate cancer. DNA methylation, EZH2 and histone modifications also ensure the parental-specific monoallelic expression of at least 62 imprinted genes. Although it is therefore tempting to speculate that epigenetic dysregulation may extend to imprinted genes, expression changes in cancerous prostates are only well documented for insulin-like growth factor 2 (IGF2). A literature and database survey on imprinted genes in prostate cancer suggests that the expression of most imprinted genes remains unchanged despite global disturbances in epigenetic mechanisms. Instead, selective genetic and epigenetic changes appear to lead to the inactivation of a sub-network of imprinted genes, which might function in the prostate to limit cell growth induced via the PI3K/Akt pathway, modulate androgen responses and regulate differentiation. Whereas dysregulation of IGF2 may constitute an early change in prostate carcinogenesis, inactivation of this imprinted gene network is rather associated with cancer progression. 相似文献