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951.
This paper focuses on two common misconceptions of common factors in therapy. The first misconception entails the confusion between common factors and therapeutic factors, and thus the inappropriate and misleading use of the term therapeutic common factors in various situations. The second misconception is the mixing of commonalities of different kinds and levels in proposed lists and studies of common factors. These areas are discussed and clarified, and recommendations designed to facilitate conceptual and methodological improvements relative to each misconception are offered. The selection of best levels and kinds of common factors to be studied are further explored (i.e., the study of client change events and antecedent therapist behaviors across different therapies), and specific proposals for their research are outlined.  相似文献   
952.
953.
We show that appetitive and aversive conditioning can be analyzed at the cellular level in the well-described neural circuitries underlying rhythmic feeding and respiration in the pond snail, Lymnaea stagnalis. To relate electrical changes directly to behavior, the snails were first trained and the neural changes recorded at multiple sites in reduced preparations made from the same animals. Changes in neural activity following conditioning could be recorded at the level of motoneurons, central pattern generator interneurons and modulatory neurons. Of significant interest was recent work showing that neural correlates of long-term memory could be recorded in the feeding network following single-trial appetitive chemical conditioning. Available information on the synaptic connectivity and transmitter content of identified neurons within the Lymnaea circuits will allow further work on the synaptic and molecular mechanisms of learning and memory.  相似文献   
954.
Infection with human immunodeficiency virus type 1 (HIV-1) leads rapidly to infection of the brain and subsequent neuropsychological impairment, including subclinical impairment, minor cognitive-motor disorder, and HIV-1-associated dementia (HAD). This article reviews HAD and the factors involved in its pathogenesis; the effectiveness of antiretroviral therapy; the prevalence of HIV-1 and subtypes; and the role of chemokines and cytokines as the capstones associated with neuropathology due to inflammation.  相似文献   
955.
Psychoneuroimmunology (PNI) is a rapidly evolving multidisciplinary field founded on the premise that psychosocial factors, the central nervous system, and the immune system are intimately linked. Following publication of scientific evidence supporting this link, a number of animal and human studies have been published, both inside and outside the area of human immunodeficiency virus (HIV) infection and acquired immunodeficiency syndrome. These studies support the existence of bidirectional feedback mechanisms operating between the brain and the immune system. To date, however, there is no all-encompassing model that predicts individual differences in the relationship among psychosocial factors, immunologic measures, and clinical disease progression in HIV type 1 (HIV-1) infection. This variability in human response has been explained by a number of cofactors (host as well as environmental) that appear to accelerate the course of the disease. Since psychosocial factors are highly amenable to behavioral interventions, several models for intervention research have been proposed to evaluate whether such interventions can enhance immune functioning, thereby curtailing disease progression. Examination of these interventions in the context of PNI and HIV-1 infection, however, is rather limited. Therefore, researchers and clinicians must not only consider conceptualizations and paradigms in this area of research, but also focus on empirically testable, theory-driven models that allow for the unique characteristics of individual patients.  相似文献   
956.
Combination pharmacotherapy has proven effective in a number of psychiatric disorders, including depression and schizophrenia. However, compared with other affective disorders, few studies have explored the use of combination therapy in alcoholism, and the majority have been limited to animal models. There is evidence to support a role for combination therapy in alcoholism. For example, several neurochemical systems, including the dopaminergic, serotonergic, and opioidergic, appear to affect alcohol intake. Studies in several different types of alcohol-preferring rats have suggested that coadministration of agents to target more than one of these systems simultaneously may produce beneficial effects on alcohol intake, while avoiding problematic effects, such as alterations in food or water intake. Data from preliminary clinical studies have shown trends toward combination therapy reducing alcohol intake in humans. While such findings are encouraging, they must be explored further in larger, randomized, double-blind trials.  相似文献   
957.
Children have been shown to prefer faces rated as highly attractive by adults over faces rated as quite unattractive. We investigated to what extent this agreement holds not only for the general direction of preferences but for preference strengths as well. In a choice experiment, we presented 40 nine-year-old girls and their mothers and 40 twelve-year-old girls and their mothers with pairs of women's and girls' faces and asked the subjects to pick the face that appeared prettier to them. Preference frequencies and simple attractiveness scales derived from these preference frequencies by fitting the Bradley-Terry-Luce rule (Luce, D. R. (1959). Individual choice behavior: a theoretical analysis. New York: Wiley) were compared across subject groups. For the women's faces, we found no difference in preferences between nine-year-olds, twelve-year-olds, and adults, neither in direction nor in strength. For the girls' faces, we also found no major differences in preference direction, however, we did find reliable differences in preference strengths. To a considerable part these differences were due to the fact that the children showed less pronounced preferences between face stimuli than the adults. These results suggest a role of developmental factors in the perception of facial attractiveness.  相似文献   
958.
Response time (RT) distributions from three fixed foreperiod conditions (2, 4, and 8 s) in a warned four-choice RT task were obtained for a group of boys with attention-deficit/hyperactivity disorder, combined type (ADHD; n = 17) and for two groups of normal control boys (age-matched, n = 18, and younger-aged, n = 10). Quantitative measures of distributional shape were derived by fitting the ex-Gaussian distributional model to the individual RT data. Statistical results indicate that the ADHD distributions differ from the age-matched control distributions with respect to the size of the tail (larger for the ADHD boys), but differ from the younger control distributions with respect to the location of the leading edge (slower for the younger control boys). Receiver operating characteristic (ROC) results reveal that the ex-Gaussian exponential component is highly diagnostic of the ADHD boys.  相似文献   
959.
Cook KV 《Adolescence》2000,35(140):717-730
This study was designed to explore Freeman's (1986) finding that the institution that made the greatest contribution to male African-American youths' socioeconomic success was the church. Thirty-two African-American, Haitian-American, and Latino male and female teenagers--16 drawn from inner-city Protestant churches and 16 comparison teenagers from the same communities-were interviewed. The interviews revealed that churched teenagers were less stressed and less likely to have psychological problems than were teenagers in the comparison group. They also appeared more likely to be living with both biological parents, less likely to have a family member on welfare, and more likely to have a job when compared with the other teenagers. They described the church as being central to their lives and as having multiple functions, many of which have been identified in the resilience literature as contributing to positive developmental outcomes. Results are interpreted in light of the transactional model, and recommendations are made, such as expanding the role of the church within these ethnic communities.  相似文献   
960.
Coard SI  Nitz K  Felice ME 《Adolescence》2000,35(137):193-200
First-time adolescent mothers are at high risk for a repeat pregnancy. The present investigation, part of an ongoing longitudinal study, examined sociodemographic, family, and health factors associated with repeat Pregnancy in a clinic sample of urban, first-time adolescent mothers (ages 13 to 17 years). They were predominantly African-American and from low-income households. Repeat pregnancy within one year and between one and two years postpartum was determined from medical records. Summary statistics, point biserial correlations, and chi-square statistics were used to analyze the data. Results indicated that postpartum contraceptive method was associated with repeat pregnancy at Year 1; contraceptive use, maternal age, history of miscarriages, and postpartum contraceptive method were associated with repeat pregnancy at Year 2. It was concluded that efforts to prevent repeat pregnancies among first-time adolescent mothers should include the continuous monitoring of contraceptive use, as well as the promotion of long-acting contraceptives (e.g., medroxyprogesterone or progesterone implants). Further, counseling should be offered to adolescent mothers with a history offered miscarriages.  相似文献   
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