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131.
Interventions to assist reproductive health decision-making in populations affected by sickle cell disease (SCD) or trait (SCT) lack proven efficacy over time. Our aim was to compare effects of CHOICES, a Web-based multimedia education program on implementing informed reproductive plans, and usual care education (e-Book) on reproductive knowledge, intention, and behavior over 24 months. We randomized 234 participants with SCD (n?=?138) or SCT (n?=?96) (age 18–35 years, 35 % male, 94 % African American) to CHOICES and e-Book groups. Participants completed a sickle cell-specific reproductive measure before and four times after the intervention (6, 12, 18 and 24 months). Compared to the e-Book group the CHOICES group had significantly more improvement in knowledge over time (p?=?.004) but not intention (p?=?.18) or behavior (p?=?.69). At baseline, 114 (48.7 %) participants reported having partners who would not put the couple at risk for their children inheriting SCD. Of the 116 (49.6 %) at-risk participants, a higher poroportion of those who were in the CHOICES group chose partners that reduced their risk by the last visit than the e-Book group (p?=?.04). Study findings provide important insights for designing a national trial of the CHOICES intervention focusing on subjects whose partner status puts them at risk for having a child with SCD.  相似文献   
132.
The effects of brief mother–infant psychotherapies (maximum of 10 sessions) were examined in cases of functional and behavioral disturbances in children less than 30 months old. Seventy-five mother-infant dyads were assessed prior to treatment, at 1 week, and 6 months after therapy ended. The outcome measures were changes in the infant's symptoms, the behavioral interactions between mother and infant, and maternal representations. The effect of two forms of intervention—Psychodynamic Therapy and Interaction Guidance Therapy—were compared. Results indicated a significant symptom reduction; dyadic interactions became more harmonious (mothers became less intrusive and infants more cooperative). Maternal self-esteem grew significantly and negative affects decreased. Improvements lasted as least several months, with some positive improvement detected at the 6-month follow-up. No major difference in outcome was found between the effects of the two forms of intervention. Within the limitations of research in a clinical context, this study suggests that brief mother–infant psychotherapies are a cost-effective method of early intervention.  相似文献   
133.
This study investigates the comprehension of a dosage according to the desired aim before reading. The results of the two experiments carried out indicate that only the cognitive activities underlying the performance of the instructions (versus comprehension/memorisation) require the transformation of the declarative representation into a procedural one. The inferences generated attest a result/procedure relation and a hierarchical organisation of the planification of actions brought into play. Moreover, information which is directly goal‐related receives more extensive treatment than other information.  相似文献   
134.
The return rate of lost postcards was hypothesized to depend upon the precision of the image that the finder can form of the relationship sender-recipient, Signature and length of the message were taken as indices and confirmed this role in two studies using a representative design.  相似文献   
135.
Analyses from an a priori full cross-fostering study (Capron & Duyme, 1989, 1991), investigating the IQs of 38 children whose average age was 168 (SE = 3.28) months, indicated a link between the socioeconomic status (SES) of both biological and adoptive parents and Full, Verbal, and Performance IQs of the WISC-R scale. Here detailed analyses of the WISC-R scale are presented. These show that these two factors affect Block Design and Information subtests, and other subtests are affected either by one or the other factor. Two subtests—Picture Arrangement and Picture Completion—are not affected by either factor. There is no evidence for an interaction between these factors on adopted children's subtest scores. As the sample size is small for a test of nonadditivity, the analysis is extended to the power of interaction test.  相似文献   
136.
This study assessed levels of psychopathology, as measured by the Symptom Checklist-90-Revised, of drug users not in treatment. These levels were then compared with levels of psychopathology reported previously in the literature of drug users in treatment, the general population, psychiatric inpatients, and psychiatric outpatients. Results suggest that drug users not in treatment endorse significantly lower levels of psychopathology than drug users in treatment, psychiatric inpatients, and psychiatric outpatients. However, they endorse significantly higher levels of pathology than adult nonpatients and they appear most similar to adolescent nonpatients. Implications for clinical work (prevention and intervention) as well as for future research are discussed. The study also established preliminary cultural validity of SCL-90-R with Alaska Natives.  相似文献   
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138.
Segmentation of target odorants from background odorants is a fundamental computational requirement for the olfactory system and is thought to be behaviorally mediated by olfactory habituation memory. Data from our laboratory have shown that odor-specific adaptation in piriform neurons, mediated at least partially by synaptic adaptation between the olfactory bulb outputs and piriform cortex pyramidal cells, is highly odor specific, while that observed at the synaptic level is specific only to certain odor features. Behavioral data show that odor habituation memory at short time constants corresponding to synaptic adaptation is also highly odor specific and is blocked by the same pharmacological agents as synaptic adaptation. Using previously developed computational models of the olfactory system we show here how synaptic adaptation and potentiation interact to create the observed specificity of response adaptation. The model analyzes the mechanisms underlying the odor specificity of habituation, the dependence on functioning cholinergic modulation, and makes predictions about connectivity to and within the piriform neural network. Predictions made by the model for the role of cholinergic modulation are supported by behavioral results.Filtering sensory input is critical for information processing tasks such as background segmentation, and shifting processing power away from redundant, stable, or repetitive stimuli toward dynamic, novel stimuli. A critical aspect of this filtering however, is stimulus specificity. Under most circumstances it may be most beneficial to selectively filter the redundant stimulus, while maintaining responsiveness to different, though perhaps highly similar stimuli.In the olfactory system, short-term habituation to stable or repeated odorants involves a metabotropic glutamate receptor (mGluR)-dependent depression of afferent synapses to the piriform cortex (Best and Wilson 2004). Blockade of group III mGluR receptors prevents cortical adaptation odors (Best and Wilson 2004), and reduces short-term habituation of odor-evoked reflexes (Best et al. 2005) and odor investigation (Yadon and Wilson 2005; Bell et al. 2008; McNamara et al. 2008). This short-term habituation is highly odor specific, with minimal cross-adaptation of piriform cortical single-unit responses or cross-habituation of behavioral responses to similar odors, including between mixtures and their components (Wilson 2000; Cleland et al. 2002). Interestingly, there is an experience-dependent component to short-term habituation odor specificity. The odor specificity is most pronounced for familiar odors, with very brief (<20 sec) exposure to odors producing more generalization, and longer exposures (>50 sec) sufficient to permit strong odor specificity in cortex adaptation (Wilson 2003).The homosynaptic nature of afferent synaptic depression underlying cortical adaptation (Wilson 1998; Best and Wilson 2004) may contribute to this odor specificity. However, the experience dependence suggests that there may be an additional process involved. In fact, theoretical views of piriform cortical function suggest that the cortex learns previous patterns of input via potentiation of intracortical association fiber synapses (Hasselmo et al. 1990; Barkai et al. 1994; Haberly 2001; Linster et al. 2003). This autoassociative process essentially creates a template of previous network activity, against which new input patterns can be compared, allowing enhanced discrimination between similar patterns, as well as completion of degraded patterns (Barkai et al. 1994; Barnes et al. 2008). In support of this hypothesis, previous work has demonstrated that disruption of normal synaptic potentiation in association fiber synapses through blockade of cholinergic muscarinic receptors (Patil et al. 1998; Linster et al. 2003), reduces odor specificity of cortical adaptation (Wilson 2001b), prevents the effects of odor experience on subsequent behavioral cross-habituation (Fletcher and Wilson 2002), and disrupts odor discrimination (Linster et al. 2001).The present series of studies further explored the role of combined afferent synaptic depression and intracortical association fiber synaptic potentiation on the specificity of cortical adaptation and odor habituation. Using a computational model of the olfactory system (Linster et al. 2007), the results suggest that activity-dependent association fiber plasticity is necessary to account for the specificity of odor habituation. Furthermore, in behavioral experiments blockade of cholinergic muscarinic receptors during habituation enhances generalization of odor habituation, consistent with the modeling and with previous electrophysiological results.  相似文献   
139.
Memory extinction, defined as a decrease of a conditioned response as a function of a non-reinforced conditioned stimulus presentation, has high biological and clinical relevance. Extinction is not a passive reversing or erasing of the plasticity associated with acquisition, but a novel, active learning process. Nifedipine blocks L-type voltage gated calcium channels (LVGCC) and has been shown previously to selectively interfere with the extinction, but not the acquisition, of fear memory. We studied here the effect of retrograde and anterograde shifts of nifedipine application, with respect to an extinction training, on the extinction of fear conditioning. Subcutaneous injection of 30 mg/kg nifedipine, at least up to 4 h before the extinction session, significantly impaired extinction, as did intraperitoneal injection of 15 mg/kg nifedipine, at least up to 2 h before extinction training. However, the injection of nifedipine also induced a strong and protracted stress response. The pharmacokinetics of nifedipine suggest that it was mainly this stress response that triggered the specific inhibition of extinction, not the blockade of LVGCC in the brain. Our results support recent findings that stress selectively interferes with the extinction, but not the acquisition, of fear memory. They also indicate that a pharmacological approach is not sufficient to study the role of brain LVGCC in learning and memory. Further research using specific genetically modified animals is necessary to delineate the role of LVGCC in fear memory extinction.  相似文献   
140.
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