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1.
Daily caloric intake regulation was studied in chronic supracollicular decerebrate rats with a complete transaction of the neural axis at the meso–diencephalic juncture and in intact controls. For 1 wk, each rat received 3 intraorally delivered meals per day. They were challenged to maintain their 3-meal daily intake over 1 wk, in which only 2 meals per day were delivered. Intact rats increased meal size to compensate for the lost opportunity to feed, whereas chronic decerebrate rats did not. Results suggest that, although the caudal brain stem, as previously shown (H. J. Grill and J. M. Kaplan, 1990), is sufficient to modulate ingestive behavior in taste reactivity and single-meal tests, it is not sufficient to regulate daily caloric intake. Although it is possible that chronic decerebrate rats retain a long-term regulatory competence that is somehow masked under the meal omission paradigm, forebrain–hindbrain interactions appear necessary for the coordination of short- and long-term control processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
EJ Masoro 《Canadian Metallurgical Quarterly》1998,1(3):243-257
Reducing the food intake of rodents to well below that of ad libitum fed animals increases the life span. This action, which gerontologists often refer to as the antiaging action of dietary restriction (DR), is due to the slowing of the aging processes. DR also maintains most physiological processes in a youthful state and delays the occurrence and/or slows the progression of age-associated disease processes. This antiaging action of DR results from the reduced intake of calories. Reduction of the body fat content does not play a causal role in the antiaging action of DR, nor does reduction in the metabolic rate. Alterations in the characteristics of carbohydrate metabolism and of oxidative metabolism in response to DR have been found that are of such a nature that they could, at least in part, underlie the antiaging action. Several theories have recently been proposed in regard to the mechanisms responsible for the antiaging action of DR, but none has been tested by rigorously designed studies. Of these theories, the one that seems most promising is based on the fact that DR protects rats and mice of all ages against the damaging actions of acute stressors. This protective action against stressors may play a major role in the antiaging action of DR. 相似文献
3.
Caparos and Linnell (2009, 2010) used a variable-separation flanker paradigm to show that (a) when cognitive load is low, increasing perceptual load causes spatial attention to focus and (b) when perceptual load is high, decreasing cognitive load causes spatial attention to focus. Here, we tested whether the effects of perceptual and cognitive load on spatial focus remain when, respectively, cognitive load is high and perceptual load is low. We found that decreasing cognitive load only causes spatial attention to focus when perceptual load is high and the stimulus encourages this. Moreover, and contrary to the widely held assumption that perceptual load focuses attention automatically (Lavie, Hirst, de Fockert, & Viding, 2004), perceptual load exerts its focusing effect only with the engagement of cognitive resources when cognitive load is low. In sum, perceptual and cognitive mechanisms exert interacting effects and operate in concert to focus spatial attention. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
4.
The daily caloric intake of 53 18–45 yr old Ss was monitored. A caloric intake monitoring (CIM)-no-goal group was compared with CIM–low-goal group, a CIM–moderate-goal group, and a CIM–high-goal group. While CIM combined with goal-setting produced more weight loss than CIM combined with no goal, various levels of goal did not differentially affect weight loss over a 4-wk period. (French abstract) (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
JP Sanderson N Binkley EB Roecker JE Champ TD Pugh L Aspnes R Weindruch 《Canadian Metallurgical Quarterly》1997,52(1):B20-B25
Caloric and fat intake may have important skeletal consequences. To evaluate this possibility, skeletal effects of adult-onset caloric restriction (CR) at differing fat intakes were assessed in male Lobund-Wistar rats. At age 17 months, two groups of animals received an anti-obesity diet, restricted approximately 35% from individual ad libitum baseline calorie consumption, and two groups received a diet approximately 50% restricted. Dietary fat concentrations were 5, 15, 15, and 25% by weight, respectively. At ages 20, 24, 28, 30, and 32 months, ex vivo femoral bone densitometry and serum biochemical analyses were performed. Body weight (BW) decreased with time on CR in each group (p < .005), declining faster at the more severe restriction (p = .001). Femoral bone mineral contents (BMC) were also reduced. After adjusting for bone area and BW differences among groups, the only significant difference was a reduction in distal femur BMC in the 25% fat group subjected to more severe CR (p = .02). No differences were observed in serum parathyroid hormone, calcium, phosphorus, or creatinine. Femoral bone loss occurred with CR. This was entirely accounted for by reduction in BW. Higher dietary fat content did not affect BW in CR animals, but did result in lower distal femur BMC. 相似文献
6.
JL Bernat 《Canadian Metallurgical Quarterly》1997,54(11):1341-1345
As the quality of neurological care becomes a mutual objective of physicians, patients, and health planners, increased demands on cost savings will create conflicts that could threaten the ethical basis of medical practice. Physicians will see increasing ethical conflicts between their fiduciary duties to make treatment decisions in the best interest of their patients and their justice-based duties to conserve societal resources. These conflicts can be best mitigated if physicians maintain their orientation as patient advocates but practice cost-conscious clinical behaviors that consider the cost-effectiveness of tests and treatments and do not squander society's finite resources by ordering medical tests and treatments of zero or marginal utility. Health system planners should resolve their conflicting objectives of quality and cost control by rigorously defining and measuring quality through physician leadership and by implementing cost-control measures that enhance the quality of medical care. Managed care organizations voluntarily should forsake financially successful but blatantly unethical cost-saving schemes, such as gag clauses and end-of-year kickback payments to physicians, because these schemes diminish patients' trust in physicians and degrade the integrity of the patient-physician relationship. State and federal laws should prudently regulate these unethical cost-saving schemes to the same extent as they have for the harmful conflicts in fee-for-service medicine. 相似文献
7.
Suggests that government has contributed to an escalation of health costs that is pushing quality health care out of reach of many Americans. The Health Care Financing Administration is seeking to correct this problem by replacing inappropriate incentives with ones that reward efficiency while assuring access to care. Provisions in the law that change benefits, encourage innovative service delivery, and provide incentives for cost-effective delivery and management are discussed. Coalitions of business, labor, and providers and consumers of health care are becoming more active in reducing health care costs by promoting alternative delivery systems and stimulating more cost-conscious behavior. (0 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Studied the behavioral development of suckling and intake control in 2 experiments with Charles River CD strain rat pups. Ss were observed at the initiation, during the course, and at the termination of suckling from their anesthetized mothers. Diet was delivered intraorally through a fine tongue cannula which enabled control of timing and volume. The control of diet intake and the behavior at termination of suckling showed correlated changes from 5 to 20 days of age. When deprived of suckling (and food and water) for 8 hr, 5- and 10-day-old Ss consumed large volumes of diet (10% of body weight or greater) and terminated suckling only in the presence of extreme gastrointestinal filling. These Ss were immediately lethargic and slept after intake termination. Five-day-old Ss persisted in reattaching to the nipple when manually stimulated; 10-day-old Ss eventually refused to reattach. In contrast, 20-day-old Ss consumed more moderate volumes of diet (5% of body weight). These Ss also remained awake for a period after feeding and engaged in the exploratory and grooming activities characteristic of adult rats at the termination of feeding. These observations demonstrate major changes in suckling behavior during development. They suggest that intake control processes shift from indirect to direct and become more effective and specifically food intake related in older pups. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
The authors propose that automatic social behavior may result from perceivers preparing to interact with primed social group members. In Study 1, participants primed with a disliked outgroup (gay men) showed evidence of interaction preparation (aggression) rather than direct stereotypic trait expression (passivity). In Study 2, participants with implicit positive attitudes toward the elderly walked more slowly after "elderly" priming, but participants with negative attitudes walked more quickly, results consistent with a preparatory account; the reverse was found priming "youth." Study 3 demonstrated that the accessibility of a primed category follows a pattern more consistent with that of goal-related constructs (including post-goal-fulfillment inhibition) than that of semantically primed constructs. Implications for the function of stored knowledge are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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11.
Investigated the influence of the lateral connections of the medial preoptic area (MPOA) on maternal behavior via the substantia nigra (SN). In Exp I, conducted with 45 postpartum lactating Charles River CD rats, the effects of large and small bilateral electrolytic lesions of SN were investigated. Large lesions severely disrupted maternal behavior and caused stereotyped activity in Ss. A 2nd experiment employed an asymmetrical lesion design and 37 Ss. Ss that received a unilateral knife cut severing the lateral connections of the MPOA and a contralateral lesion of the SN showed larger deficits in maternal behavior than either sham Ss or Ss that received a unilateral preoptic cut paired with an ipsilateral SN lesion. Measurements of body weights, body temperatures, and stereotyped behavior indicated that the differences in maternal behavior between the ipsilateral and contralateral groups could not be explained on the basis of nonspecific effects. (57 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
12.
Conducted 2 experiments with 118 adult Sprague-Dawley rats to compare the effects of androgens with those of estrogens and examine the role of target-tissue metabolism in actions of testosterone on body weight. Castration of adult males produced a delayed (by 1 mo), permanent hypophagia and reduction in weight gain. This contrasted with the rapid, transient hyperphagia and increased weight gain caused by ovariectomy in females. Injections of testosterone propionate (TP) stimulated food intake and weight gain in castrated males. Neither 5alpha-reduction nor aromatization of the testosterone molecule played an important role in the stimulation of these measures by TP. The 5alpha-reduced metabolite of TP, 5alpha-dihydrotestosterone propionate (DHTP), was less effective in increasing eating and weight gain than was TP. Very high doses of TP actually reduced weight gain with prolonged treatment (2-6 wks). It is suggested that this reduced weight gain was due to aromatization of TP to an estrogen. The nonaromatizable androgen, DHTP, did not reduce weight gain even in very high doses, and concurrent progesterone injections reversed the weight-reducing actions of high TP doses. (38 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
13.
This study is an investigation of the moderating effect of cognitive schema on the relationship between stress and depression in individuals with multiple sclerosis (MS). In the study, the authors employed a performance-based measure of affective memory bias and a self-report measure of everyday stress to assess both direct and interactive effects of cognitive schema and stress on depression in individuals with MS. The specific hypotheses were that high stress would be more highly associated with depression if an individual also demonstrated a bias for negative information, but that a bias for positive information may buffer against the effects of stress on depression. Results supported the hypotheses, demonstrating a significant effect of the interaction and differential effects of stress based on the direction of memory bias. Implications for understanding depression in MS are discussed, as well as dominant theories of adult depression in the general population. The results are also discussed as a potential contradiction to A. T. Beck's (1967, 1976) developmental hypothesis of cognitive schemas. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
14.
Recent research (T. H. Macan, 1994) questioned the importance of time management in predicting performance. The authors tested the hypothesis that time management behaviors interact with achievement striving to predict car sales performance. On the basis of data from 102 salespeople, moderated regression analyses supported that hypothesis. There was a significant interaction between short-range planning and achievement striving. Results show how time management is related to job performance under conditions of high motivation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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16.
Reilly-Harrington Noreen A.; Alloy Lauren B.; Fresco David M.; Whitehouse Wayne G. 《Canadian Metallurgical Quarterly》1999,108(4):567
This study examined the interaction of cognitive style (as assessed self-report and information-processing battery) and stressful life events in predicting the clinician-rated depressive and manic symptomatology of participants with Research Diagnostic Criteria lifetime diagnoses of bipolar disorder (n?=?49), unipolar depression (n?=?97), or no lifetime diagnosis (n?=?23). Bipolar and unipolar participants' attributional styles, dysfunctional attitudes, and negative self-referent information processing as assessed at Time 1 interacted significantly with the number of negative life events that occurred between Times 1 and 2 to predict increases in depressive symptoms from Time 1 to Time 2. Within the bipolar group, participants' Time 1 attributional styles and dysfunctional attitudes interacted significantly, and their self-referent information processing interacted marginally, with intervening life events to predict increases in manic symptoms from Time 1 to Time 2. These findings provide support for the applicability of cognitive vulnerability–stress theories of depression to bipolar spectrum disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
17.
M Mayer 《Canadian Metallurgical Quarterly》1998,270(1):55-64
Event-related potentials (ERPs) evoked by light flashes and auditory tones in a standard odd-ball procedure were recorded from Fz, Cz and Pz scalp sites. Tonic pain was evoked by immersion of the hand in cold water (5 degrees C). Significant effects of pain were found in responses to target stimuli but not in responses to non-target stimuli. P300 wave was affected more than the earlier P200 component. The reduction of P300 amplitude was the strongest effect, both in auditory and visual tests. P300 latency was not significantly affected. Difference curves (target minus non-target ERPs) showed the additional effects: latency of P200 component was elongated and its amplitude enlarged but only in auditory experiments. In control experiments with warm water stimulation no significant alterations of P300 or P200 components were found. The results show that the effect of tonic pain is specific: it predominantly affects the processes that manifest themselves as amplitude changes of P300 components in responses to target stimuli. 相似文献
18.
The conditions under which laboratory animals are maintained can powerfully influence the results of toxicological studies utilized for risk assessment. Nutrition is of importance in toxicological bioassays and research, because diet composition and the conditions under which it is fed can affect the metabolism and activity of xenobiotic test substances and alter the results and reproducibility of long-term studies. It is known that ad libitum (AL) overfed sedentary laboratory rodents suffer from an early onset of degenerative disease and diet-related tumors that lead to poor survival in chronic bioassays. AL-fed animals are not well-controlled subjects for any experimental studies. Examination of study-to-study variability in food consumption, body weight, and survival in carcinogenicity studies for the same strain or stock of rodents shows tremendous laboratory-to-laboratory variability. However, a significant correlation between average food (calorie) consumption, adult body weight, and survival has been clearly established. The use of moderate dietary restriction (DR) results in a better controlled rodent model with a lower incidence or delayed onset of spontaneous diseases and tumors. Operationally simple, moderate DR significantly improves survival, controls adult body weight and obesity, reduces age-related renal, endocrine, and cardiac diseases, increases exposure time, and increases the statistical sensitivity of these expensive, chronic bioassays to detect a true treatment effect. A moderate DR regimen of 70-75% of the maximum unrestricted AL food intake is recommended as a nutritionally intelligent, well-established method in conducting well-controlled toxicology and carcinogenicity studies. 相似文献
19.
Executive processes necessary for flexible switching between different tasks were studied using a set switching paradigm that requires Ss to rapidly switch between different tasks across consecutive trials. Switch cost reflects poorer performance for task-switch trials than for consecutive same-task trials. 34 Ss (aged 18–48 yrs) participated in the study. Significant switch cost was observed even with considerable preparation time before a task-switch, an effect known as residual switch cost. The study tested the hypothesis that one process underlying residual switch cost is inhibition of the previous task-set. The authors used semantic categorization tasks to compare switch cost between alternating task series (ABA) and nonalternating series (ABC) in order to test the generality of a task-set inhibition effect previously observed with perceptual judgment tasks. The results yielded significant switch cost only for alternating tasks, in both response times and errors resulting from performance of the wrong task. Thus, resolving inhibition associated with previously abandoned task-sets may be the main process underlying residual switch costs, suggesting that task-set inhibition is an important executive control process. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
20.
Investigated whether the interaction between endogenous cueing and stimulus/response (S/R) would be obtained if attention was controlled exogenously, using 16 Ss. Central and peripheral cues were used to endogenously or exogenously direct the S's attention to the location at which an increase or decrease in the size of a peripheral object was most likely to occur. For each S, one size change was more likely to occur than the other, and the task was choice reaction time (RT; expansion/contraction). S/R probability (particular size change) interacted with cue condition (valid, neutral, and invalid) when the cues were central (endogenous), but the 2 variables were additive when the cues were peripheral (exogenous). Data suggest that controlled allocation of attention in response to a peripheral cue involves qualitatively different mechanisms from those associated with endogenous generation of an expectancy. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献