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611.
ABSTRACT.

Objectives: Vaginoplasty presents the main problem in male to female surgery. There are many operative techniques that can be used, but none is ideal. We present our one stage vaginoplasty in male to female sex reassignment surgery.

Patients and Methods: The principle of our technique is based on penile disassembly and usage of all penile entities for vaginoplasty except corpora cavernosa. We developed our disassembly technique on a very large number of severe hypospadias reconstruction and adrenogenital “conversions.” Penile skin flaps and urethral work are used in each of these. Our new vagina consists of two parts: a long vascularized urethral flap and a pedicled island tube skin flap created from the penile skin. The urethral flap is embedded into the skin tube. The tube, consisting of skin and urethral flap, is inverted, thus forming the new vagina. The new vagina is inserted into the previously prepared perineal cavity between the urethra, bladder, and rectum. The new vagina is fixed to the sacrospinous ligament. The labia minora and majora are formed from the remaining penile and scrotal skin.

Results: The follow-up ranged from 3 months to 6 years (mean 4.6 years). Good cosmetic and functional results were obtained in 77 out of 89 patients (87%).

Conclusions: The technique provides results that have the most normal anatomical and physiological characteristics, in comparison to other methods, since all penile entities are used (except corpora cavernosa) to form almost normal external female genitalia. Vaginoplasty using pedicled penile skin with a urethral flap could be a very good alternative to other methods of vaginoplasty.  相似文献   
612.
613.
闫国利  刘敏  孟珠  张莉  李赛男 《心理科学》2019,(5):1113-1119
字形信息在汉语阅读中具有重要作用。小学二年级是儿童阅读流畅性发展的重要时期,而对注视点右侧字词的预加工及所获得的预视效应是影响流畅阅读的重要因素。本研究考察了字形信息在二年级学生预加工中的作用。实验1采用副中央凹启动范式发现,在词汇识别任务中,二年级学生在100ms副中央凹启动时间下,表现出字形预视效应。实验2采用边界范式发现,在句子默读任务中,二年级学生能够获取副中央凹处的字形信息。结果表明,二年级学生在阅读中能够使用副中央凹处的字形信息,促进随后中央凹处的词汇加工。  相似文献   
614.
Under normal circumstances, perception runs very fast and seemingly automatic. In just a few ms, we go from sensory features to perceiving objects. This fast time course does not only apply to general perceptual aspects but also to what we call higher-level judgements. Inspired by the study on ‘very first impressions’ by Bar, Neta, and Linz (2006, Emotion, 6 , 269) the current research examined the speed and time course of three aspects of the aesthetic experience, namely beauty, specialness, and impressiveness. Participants were presented with 54 reproductions of paintings that covered a wide variety of artistic styles and contents. Presentation times were 10, 50, 100 and 500 ms in Experiment 1 and 20, 30 and 40 ms in Experiment 2. Our results not only show that consistent aesthetic judgements can be formed based on very brief glances of information, but that this speed of aesthetic impression formation also differs between different aesthetic judgements. Apparently, impressiveness judgements require longer exposure times than impressions of beauty or specialness. The results provide important evidence for our understanding of the time course of aesthetic experiences.  相似文献   
615.
People acquire new beliefs in various ways. One of the most important of these is that new beliefs are acquired as a response to experiencing events that one did not expect. This involves a form of inference distinct from both deductive and inductive inference: abductive inference. The concept of abduction is due to the American pragmatist philosopher C. S. Peirce. Davies and Coltheart (in press) elucidated what Peirce meant by abduction, and identified two problems in his otherwise promising account requiring solution if that account were to become fully workable. Here we propose solutions to these problems and offer an explicit cognitive model of how people derive new beliefs from observations of unexpected events, based on Peirce’s work and Sokolov’s ideas about prediction error triggering new beliefs. We consider that this model casts light not only upon normal processes of belief formation but also upon the formation of delusional beliefs.  相似文献   
616.
Two studies examined whether morality-related information has a greater impact than sociability- or competence-related information upon the spontaneous mimicry of an interaction partner. Participants were video recorded during an interaction with a confederate previously presented as moral versus lacking morality, or sociable versus lacking sociability (Study 1), or competent versus lacking competence (Study 2). Two coders rated the extent to which participants imitated the gestures of the confederate, participants’ postural openness, and the general smoothness of the interaction. When the confederate lacked moral qualities, mimicry and postural openness were lower, and the interaction was less smooth than when the confederate was highly moral, unsociable, or incompetent. Moreover, our findings showed that global impression is the key mediating mechanism driving such an effect. Indeed, knowing that another person behaved immorally resulted in a negative impression, which in turn hindered behavioral mimicry.  相似文献   
617.
Pigeons were exposed to multiple and concurrent second-order schedules of token reinforcement, with stimulus lights serving as token reinforcers. Tokens were produced and exchanged for food according to various fixed-ratio schedules, yielding equal and unequal unit prices (responses per unit food delivery). On one schedule (termed the standard schedule), the unit price was held constant across conditions. On a second schedule (the alternative schedule), the unit price was either the same or different from the standard. Under conditions with unequal unit prices, near-exclusive preference for the lower unit price was obtained. Under conditions with equal unit prices, the direction and degree of preference depended on ratio size (number of responses per exchange period). When this ratio differed, strong preferences for the smaller ratio were observed. When this ratio was equal, preferences were nearer indifference. Response rates on the multiple schedule were generally consistent with the preference data in showing sensitivity to ratio size. Results are discussed in terms of a unit-price model that includes handling and reinforcer immediacy as additional costs. On the whole, results show that preferences were determined primarily by delay to the exchange period.  相似文献   
618.
Phasic and tonic measures of electrodermal activity were examined in a simple habituation paradigm, using innocuous visual stimuli. Separate groups were used to investigate the effects of stimulus significance, as manipulated by instructions. One group had no stimulus-related task (indifferent group), while the other was asked to silently count the stimuli to report to the experimenter later (significant group). Prestimulus skin conductance levels were considered as measures of the arousal level at each stimulus presentation, and the subsequent electrodermal responses were taken as the phasic orienting reflex (OR) elicited by each stimulus. Changes in prestimulus arousal were taken as measures of the tonic OR to the experimental series. Marked group differences were found in both phasic and tonic components of the OR. Some, but not all, of the significance effects in the phasic OR were attributable to differences in arousal. The results are discussed in the context of theoretical accounts of the OR.  相似文献   
619.
The present study investigated the influence of sex, handedness, level in second langua ge (L2) and Faculty choice on the performance of phonological, syntactical and semantic tasks in L2. Level in L2 and sex were the most affecting factors. Subjects who achieved higher scores on L2 tasks had strong second language aptitude skills since they were those who had obtained a professional degree in the second language. Females performed better than males in syntax and semantics which is explained by the general female superiority on verbal tasks based on differences in hemispheric specialization for language functions between the sexes. Handedness and Faculty choice on the part of the participants had an impact on our results but only when combined with other factors.  相似文献   
620.
Consider the process of raising and lowering the arm in the sagittal plane. Different parts of different muscles operate over different sectors of the angular range. How and why does the nervous system implement this differential muscle activation according to joint angle? We contend that such control depends on the adaptive formation of motor maps. These solve the problem of redundancy in the musculoskeletal system by connecting a relatively small number of cortical columns in the motor cortex to a large number of alpha motor neuron pools. We argue that motor maps are formed such that each functional muscle is activated in proportion to its moment arm about the movement. Because of this the required agonist and antagonist turning forces are generated with a minimum demand for metabolic energy. We know from biomechanical principles that, at any given posture, those muscle fibres that change length most in response to a small joint-angle change are those with the greatest moment arm. Likewise those that change least have the smallest. By establishing a model of the polynomial relationships between the lengths of functional muscles l and the corresponding changes in joint angles theta, the nervous system can generate signals partial differentiallj/ partial differentialthetai (where lj is the length of the jth functional muscle and thetai is the magnitude of the ith elemental movement). These signals create motor maps by modulating the gains of descending motor pathways. As a result, functional muscles are activated in proportion to their moment arms. This reduces the demand for metabolic energy to a minimum. Since moment arms change with joint angle, it also accounts for the experimental observations above. Such motor mapping effectively provides a minimum energy "wired-in" synergy. Established in utero, motor maps are the first stage of synergy formation and provide the basis for the development of subsequent task-dependent synergies.  相似文献   
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