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981.
A 1999 study of United Kingdom servicemembers by Unwin, et al. recently found significant relationships between anthrax and other vaccinations, reactions to those vaccines, and later health problems for male current or former active military Gulf War veterans. Likewise, in 2000 Steele and in 1998 Gilroy found possible adverse effects of vaccinations on Gulf War veterans. However, the role of such vaccinations remains controversial; more recent government reports continue to dispute the existence of any data that might reflect adversely on the role of vaccinations on the health of Gulf War veterans. To address this controversy, the current study assessed similar relationships for over 900 Reserve Component Gulf War Era veterans from Ohio and nearby states. Gulf War veterans were more likely to report poorer health than non-Gulf veterans. Female veterans were more likely to report mild or severe reactions to vaccines than male veterans. Those veterans who received anthrax vaccine reported more reactions to vaccines than those who did not receive anthrax vaccine. Declines in long-term subjective health were associated with receipt of anthrax vaccine by Gulf War veterans but not for those who did not deploy to the Gulf, although few of the latter received anthrax vaccine. Regardless of deployment status, veterans who reported more severe reactions to vaccines were more likely to report declines in subjective health. Female veterans reported poorer health during the Gulf War than did male veterans, but sex was not related to veterans' reports of subjective health at subsequent times. It is recommended that servicemembers who experience severe reactions to anthrax vaccine be medically reevaluated before receiving further anthrax vaccine and that careful follow-ups be conducted of those receiving the vaccine currently, in accordance with Nass's 1999 recommendations. We also recommend that safer alternatives to thimerosal (a mercury sodium salt, 50% mercury) be used to preserve all vaccines.  相似文献   
982.
Four experiments examined whether the psychological refractory period (PRP) effect can be eliminated with ideomotor compatible (IM) but not stimulus-response compatible (SR) tasks, as reported by A. G. Greenwald and H. G. Shulman (1973). Their tasks were used: a left or right movement to a left- or right-pointing arrow (IM) or to the word left or right (SR) for Task 1; saying "A" or "B" (IM) or "1" or "2" (SR) to an auditory A or B for Task 2. The stimulus onset asynchronies were 0, 100, 200, 300, 500, and 1,000 ms in Experiment 1, and only 0, 100, 200, and 1,000 ms in Experiments 2-4. The arrow was in the center of the screen in Experiments 1-3 and to the left or right in Experiment 4. As in Greenwald and Shulman's Experiment 2, the instructions stated that most often the 2 stimuli would be presented simultaneously. A PRP effect was obtained in all conditions, most likely because response-selection decisions are required even for IM tasks.  相似文献   
983.
Four–month–old infants were exposed to sequences in which a 2–s light stimulus alternated with dark interstimulus periods whose length was manipulated to be 3 or 5 s. A predictable on–off pattern occurred for eight trials, but the light stimulus was omitted on the ninth trial. Infants showed heart rate responses on the omission trial that were closely synchronized with the expected recurrence of the stimulus. In addition, these heart rate patterns were observed predominantly in infants who had previously shown high levels of sustained attention in pretests with visual stimuli. These findings indicate remarkable precision in infants' estimation of time intervals, and suggest that the link between time estimation and attentional processes is present in early infancy.  相似文献   
984.
This article describes a large sex difference on a new, group-administered visuospatial task, the Judgment of Line Angle and Position (JLAP) test, and investigates the role of attentional factors in the difference. On the JLAP, adapted from a neuropsychological task (Benton et al., 1983), participants evaluate spatial attributes of lines. Study 1: College males (N = 48) outperformed females (N = 80), resulting in a large effect for sex (d = 0.85). Errors were more common on oblique (vs horizontal or vertical) lines, especially for females. Study 2: Task attributes were manipulated (N = 33 males and 36 females) to study the role of attentional factors. Findings suggest that males are more likely than females to normally attend to and be aided by geometrical reference cues.  相似文献   
985.
Text comprehension processes were investigated in children with hydrocephalus, a neurodevelopmental disorder associated with good word decoding, but deficient reading comprehension. In Experiment 1, hydrocephalus and control groups were similar in processes related to activating word meanings and using context to enhance meaning. The hydrocephalus group was poorer at suppressing contextually irrelevant meanings. In Experiment 2, the hydrocephalus group had difficulty integrating information from an earlier read sentence to understand a new sentence as textual distance between the two propositions increased, suggesting difficulty in reactivation processes related to comprehension. Results are discussed in relation to cognitive and neurocognitive models of comprehension.  相似文献   
986.
The associations among suicidal behavior, negative affect, and delinquency were assessed via an anonymous self-report survey administered to male and female college students ( N = 383). Contrary to our hypothesized results, there were no gender differences in rates of suicidal ideation and attempts. Confirming our hypotheses about gender differences, college men did report significantly more delinquent behavior than college women. College men also scored higher on the suicide-proneness scale, which contained a mixture of death-related, risk-related, and negative self- and health-related items. Furthermore, as predicted, college students with a history of depression, suicide ideation, and/or suicide attempts all reported significantly more delinquent behavior. Self-reported delinquency and current levels of depressive symptomology emerged as significant predictors of suicide-prone behavior for both college men and women, explaining 34% of the variance for women and 17% for men. Levels of engagement in suicide-prone behavior and feelings of depression were elevated in college students with any type of juvenile arrest history. Students with an arrest history were also more likely to have had a diagnosis of depression and to have engaged in suicide ideation in their past. These findings suggest there are complex links between depression, delinquency, and suicidal behavior in college men and women.  相似文献   
987.
Prior experiments, as well as computational models, have implicated the hippocampal region in mediating the influence of nonreinforced stimulus preexposure on subsequent learning. Learned irrelevance (LIRR) is a preexposure task in which uncorrelated preexposures to the conditioned stimulus (CS) and the unconditioned stimulus (US) produce a retardation of subsequent CS-US conditioning. In the work presented here, we report the results of tests of LIRR in eyeblink conditioning in rabbits with sham lesions, nonselective cortical-hippocampal region lesions, selective hippocampal lesions, and selective entorhinal lesions. Sham-lesioned rabbits that had been preexposed to the CS and the US exhibited slower acquisition of conditioned response, as compared with context-preexposed controls. Nonselective cotical-hippocampal region lesions disrupted LIRR, whereas selective hippocampal lesions had no detrimental effect on LIRR. Selective entorhinal lesions disrupted LIRR. These findings fit other recent empirical findings and theoretical predictions that some classical conditioning tasks previously thought to depend on the hippocampus depend, rather, on the entorhinal cortex.  相似文献   
988.
Psychology as a profession has entered the arena of palliative and hospice care later in the process than other health care professions. Through the use of Familial Advance Planning Evaluations (FAPEs), however, psychologists can assist individuals and families in facing end-of-life transitions in important ways. Hospice and palliative care philosophy treats the patient and family as the unit of care. End-of-life decision-making is therefore a family matter as well as a normative developmental transition. Yet, little is known about the decision-making process. This paper reviews the literature regarding informed consent, advance care planning, and proxy decision-making and outlines a theoretical model for familial decision-making. Previous models of end-of-life capacity evaluations and family assessments are presented and serve as the basis for a comprehensive assessment of familial decision-making at the end of life. Functional capacity evaluations of individuals at the end of life regarding decisions about life-sustaining medical treatments enable both the individual patient and one identified proxy from his or her family to discuss important issues families may face during medical crises at the end of life. The information gleaned from such evaluations has the potential to assist psychologists and other professionals in designing family-specific interventions to reduce caregiving distress, improve quality of life for dying patients, and ease the transition to bereavement for caregivers.  相似文献   
989.
The focus of neonatal intensive care has been on very low birthweight infants, who comprise only 1.4% of neonates. Too little attention is paid to moderately preterm infants that we call macropremies or moderately low birthweight infants (MLBW, with birthweights 1500-2500 grams). Admitting over half MLBW infants to normal nurseries presumes that they have few needs and an excellent prognosis similar to fullterm newborns. It does not take into account the macropremie's vulnerability to complications of prematurity due to immature organ systems. Obstetricians are increasingly willing to deliver these infants prematurely for signs of fetal distress. As many as 25% of children with cerebral palsy referred to a disability clinic in Paris were MLBW, with hypoxic-ischemic-inflammatory associated disorders in one-third. The majority of MLBW infants who required neonatal intensive care at a tertiary care center in Baltimore had complications of prematurity: 47% had respiratory problems, 20% had feeding intolerance and 9% had hypoglycemia. MLBW infants comprise 5-7% of the neonatal population but account for 14% of neonatal deaths, 18-37% of children with cerebral palsy and 7-12% of children with mental retardation. Increasing the level of neonatal care for the macropremie's transition to extrauterine life would be economically feasible if it prevented as few as 30% of cases of major disability. A change in attitude towards this low risk (but not risk free) group of MLBW infants will both reduce morbidity and improve their health and neurodevelopmental outcome. It includes: 1) Providing an intermediate level of neonatal care for a short duration, with close monitoring and prompt intervention as needed, and 2) Neonatal neurodevelopmental screening to allow focused neurodevelopmental followup of MLBW infants with abnormalities.  相似文献   
990.
Thirty-nine patients, mostly schizophrenics, on a token-economy ward were available to attend up to 30 occupational therapy (OT) sessions divided into 5 reinforcement conditions: free, patients paid, free, patients were paid, free. Four groups of patients were identified according to the condition and session in which they first responded. Group 1 patients began to attend without reinforcement by the third free session. Group 2 patients who began to attend by the second session in the second free condition were less sensitive to rewards than Group 1 members but possibly modeled their behavior after Group 1. The Group 3 members began to attend when given token reinforcers. Group 4 members never emitted the required response. Inadequacies of the grouped-data statistics used by previous researchers in evaluating token economy programs are discussed and it is suggested that in evaluation procedures patients should be separated into groups and the responses from each group be presented in cumulative curves.  相似文献   
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