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1.
Gathered measures of personal space from 74 children (ages 3, 5, and 7) when they approached boys or girls of their own age. A significant difference was found between the 3-yr-olds (who kept less distance from their age peers) and the 5- or 7-yr-olds. No other differences attributable to age were found. For all Ss, the sex of the interacting child was relevant in that less distance was kept from girls than from boys. Results are discussed in the light of learning and developmental processes. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

2.
By employing dual-digitonin-pulse perfusion technique, the cytosolic fractions were prepared from periportal (PP) and perivenous (PV) hepatocytes of male and female rat livers. Sulfotransferase (ST) activities toward 2-naphthol (2NAP) (at pH 5.5 and 7.4), 4-nitrophenol, dehydroepiandrosterone (DHEA), and cortisol were measured in each fraction. DHEA-ST activity was mainly localized in PP fraction in males, while in females it was slightly higher in PP fraction than in PV samples. In contrast, phenol ST activities were higher in PV fraction in both sexes. With anti-HS-ST and anti-P-ST antisera, the levels of immunoreactive ST polypeptides were compatible with the levels of ST activities except that in female PP fraction the level of immunoreactive P-ST polypeptide was low in spite of comparatively high levels of P-ST activities. Chromatofocusing of PP and PV fractions separated P-ST activities into three major fractions (I-III), which have distinct catalytic and electrochemical properties. Fraction I was localized only in the PP samples in both sexes and revealed ST activities toward 2NAP at pH 5.5 and 7.4, while fraction II was localized in the PP and PV samples in both sexes with 2NAP-ST activity only at pH 7.4. Fraction III which had ST activities at pH 5.5 and 7.4 was present only in the PV samples in female rats, whereas in male rats it was present in both PP and PV samples. With anti-P-ST antiserum, the immunoreactive polypeptide was present in fraction III, but no immunoreactive band was detected in fractions I and II, suggesting the presence of immunochemically and electrochemically different P-ST(s) in these fractions.  相似文献   

3.
Biosynthesis of the neuroactive steroids pregnenolone sulfate (delta5PS) and dehydroepiandrosterone sulfate (DHEAS) is catalyzed by the enzyme hydroxysteroid sulfotransferase (HST), which transfers the sulfonate moiety from 3'-phosphoadenosine 5'-phosphosulfate (PAPS) on the 3-hydroxy site of steroids. Although high concentrations of delta5PS and DHEAS have been detected in the rat brain, the anatomical localization of HST in the CNS has never been determined. Using an antiserum against rat liver HST, we have investigated the distribution of HST-like immunoreactivity in the CNS of the frog Rana ridibunda. Two populations of HST-immunoreactive neurons were observed in the hypothalamus, and several bundles of positive nerve fibers were visualized in the telencephalon and diencephalon. Incubation of frog brain homogenates with [35S]PAPS and [3H]pregnenolone yielded the formation of several 3H,35S-labeled compounds, including delta5PS and testosterone sulfate. When [3H]dehydroepiandrosterone and [35S]PAPS were used as precursors, one of the 3H,35S-labeled metabolites coeluted with DHEAS. Neosynthesis of [3H]delta5PS and [3H]DHEAS was reduced significantly by 2,4-dichloro-6-nitrophenol, a specific inhibitor of sulfotransferases. The present study provides the first immunocytochemical mapping of HST in the brain. Our data also demonstrate for the first time that biosynthesis of the highly potent neuroactive steroids delta5PS and DHEAS occurs in the CNS of nonmammalian vertebrates.  相似文献   

4.
Hand function related to age and sex   总被引:1,自引:0,他引:1  
After adapting Jebssen's Test of Hand Function to Australian conditions, this study investigated his claim of no significant difference in hand performance among participants younger than 60 years, and determined whether age might be a factor when associated with sex. The method was to test 383 subjects of both sexes in 6 age groups. A 2-factor analysis with age and sex as factors yielded significant differences (p less than 0.01) for "grip strength" "manipulating small objects," and "moving large heavy objects," and indications of significance (p less than 0.05) for "card turning" and "moving large light objects." The sex factor showed males to be significantly better "grip strength," in "moving large heavy objects," and "large light objects," except in the 66-99 age interval where females were significantly better on teh last 2 variables. Females performed better on "writing" and were generally better in "manipulating small objects." These results suggest that the one set of norms given by Jebsen for 60 years and less for each sex, should be replaced by 5 or more, even though the differences were quite small when standard deviations were considered.  相似文献   

5.
A population of 194 lemurs (Lemur spp.), 116 males and 78 females, from 1 to 30 years of age, was assessed for lateralized hand use in simple food reaching with a minimum of 100 reaches per animal. A hand preference was present in 80% of the population with a bias for use of the left hand that was most characteristic of male lemurs and young lemurs. The results confirm the presence of lateralization in prosimians, and we interpret the sex and age differences in relation to current theories of neural lateralization. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

6.
A large public service organization was concerned with protection of its customers against hazards associated with furniture tipping in public use concourses. Because no injury experience was available for analysis, hazard patterns for tipping accidents were developed from an observational study of public interaction with the furniture. For each hazard pattern, anthropometric models were used to find the probability of the furniture being safe from tipping, for different age and gender combinations. A safety criterion was developed from this modeling, and used to change the weights of some furniture items to resist tipping. These modifications have now been implemented and are in widespread use. Implications for broader application of these models to the development of valid tipping standards for furniture are discussed.  相似文献   

7.
Exposed 52 female Sprague-Dawley albino rats to an open field for 5 min. daily between the ages of 31-110 days. Ss 40 days old or younger showed day-to-day increments in activity during repeated apparatus exposures, while no group 70 days old or older showed this activity change. In Exp. II groups of 9 Ss, 31 and 110 days old, respectively, were given 60 open-field trials. The juveniles increased their activity and maintained this elevated behavior; adults never did exhibit any significant increase in activity. Results indicate a critical period among rats such that high rates of ambulation are typical of only those animals that are placed in the apparatus prior to Day 70. (22 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

8.
Each of 3 experiments demonstrated that female Sprague-Dawley albino juvenile rats (n = 24) become increasingly active during 10 consecutive trials in the open field; adults (n = 24) did not show this day-to-day change. Age-related activity change was unaffected by food deprivation and is interpreted to be a consequence of the greater curiosity and ease in familiarization with a novel environment among juveniles. The greater intensity of ambulation among immature Ss may provide an explanation for age-related differences in appetitive learning. (24 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

9.
8 male and 8 female Es each tested 8 male and 8 female Ss in a simple sorting task. During an initial 1.5 min. each S's base rate of response was ascertained; following this, the E delivered a supportive statement every 30 sec. for the next 5.5 min. Performance did not increase as a function of the introduction of the supportive statements. Significant differences in base rate and in performance after the base rate period were found as a function of sex of E and of the interaction between sex of E and sex of S. Highly reliable differences appeared in the performance of Ss tested by different Es. The rank-order correlations of men and women tested by men and by women were significant, indicating a similar hierarchy in level of performance of male and female Ss tested by the male Es and a similar hierarchy for Ss tested by female Es. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

10.
11.
Dietary intake of the essential trace element selenium (Se) regulates expression of genes for selenoproteins and certain non-Se-containing proteins. However, these proteins do not account for all of Se's biological effects. The objective of this work was to identify additional genes whose expression is regulated by Se. Identification of these genes may reveal new functions for Se or define mechanisms for its biological effects. Weanling male Sprague-Dawley rats were fed a Torula yeast-based Se-deficient basal diet or the same diet supplemented with 0.5 mg Se/kg diet as sodium selenite for 13 weeks. Total RNA was used as template for RNA fingerprinting. Two differentially expressed cDNA fragments were identified and cloned. The first had 99% nucleotide identity with rat liver estrogen sulfotransferase (EST) isoform-6. The second had 99% nucleotide sequence identity with rat liver alpha 2u-globulin. The mRNA levels for both were markedly reduced in Se deficiency. Laser densitometry showed that EST mRNA in Se deficiency was 7.3% of that in Se-adequate rat liver. The level of alpha 2u-globulin mRNA in Se-deficient rat liver was only 12.6% of that in Se-adequate rat liver. These results indicate that dietary Se may play a role in steroid hormone metabolism in rat liver.  相似文献   

12.
In substantia nigra from patients with Parkinson's disease, there are decreased levels of reduced glutathione (GSH) and diminished activities of mitochondrial complex I and alpha-ketoglutarate dehydrogenase (alpha-KGDH), along with increased activity of superoxide dismutase (SOD). However, the interrelationship among these events is uncertain. We now report the effect of decreased brain GSH levels on SOD and mitochondrial respiratory enzyme activity in rat brain. In addition, we have investigated the ability of thioctic acid, an endogenous antioxidant, to alter these parameters. Unilateral or bilateral intracerebroventricular (ICV) administration of buthionine sulphoximine (BSO; 1 x 3.2 mg or 2 x 1.6 mg) over a 48-hr period reduced cortical GSH by 55-70%. There was no change in the activity of complex I, II/III, or IV or of citrate synthase in cortex. Similarly, there was no alteration of mitochondrial or cytosolic SOD activity. Thioctic acid (50 or 100 mg/kg IP) alone had no effect on cortical GSH levels in control animals and did not reverse the decrease in GSH levels produced by unilateral or bilateral ICV BSO administration. Thioctic acid (50 or 100 mg/kg IP) had no overall effect on complex I, II/III, or IV or on citrate synthase activity in control animals. Thioctic acid also did not alter cortical mitochondrial respiratory enzyme activity in BSO-treated rats. At the lower dose, thioctic acid tended to increase mitochondrial and cytosolic SOD activity in control animals and in BSO-treated rats. However, at the higher dose, thioctic acid tended to decrease mitochondrial SOD activity. Overall, there was no consistent effect of thioctic acid (50 or 100 mg/kg IP) on SOD activity in control or BSO-treated animals. This study shows that BSO-induced glutathione deficiency does not lead to alterations in mitochondrial respiratory enzyme activity or to changes in SOD activity. GSH depletion in Parkinson's disease therefore may not account for the alterations occurring in complex I and mitochondrial SOD in substantia nigra. Thioctic acid did not alter brain GSH levels or mitochondrial function. Interestingly, however, it did produce some alterations in SOD activity, which may reflect either its antioxidant activity or its ability to act as a thiol-disulphide redox couple.  相似文献   

13.
The characteristics of sleep spindles as a function of age were studied with an automated analysis system. Five age groups (group 0, 3-5 years; I, 13 years; II, 25-34 years; III, 42-53 years; and IV, 67-79 years) were analyzed. Significant differences in spindle frequency were found between groups 0-I and II-III-IV. The frequency increased with increasing age. No age differences were found in spindle duration. Spindle amplitude reached a peak in the group I subjects, then decreased with increasing age.  相似文献   

14.
Lifestyle practices and the health promoting environment of hospital nurses This paper examined the lifestyle practices of hospital nurses and the impact of specific interventions in the hospital environment. The perception of nurse as health promoter and as carer of AIDS patients was also examined. A self-administered questionnaire was used to collect data at two different time periods. The sample represented 729 nurses (at pre- and post-time periods), both qualified and student nurses. Qualified nurses reported the highest stress levels while student nurses reported more negative lifestyle practices such as smoking, alcohol consumption and drug use. A greater number of current smokers (29%) consumed alcohol and used drugs than non-smokers. The impact of intervention strategies around compliance with smoking policy and work-site walk routes reduced exposure to passive smoking at work for qualified nurses and increased exercise participation for both groups of nurses. Workplace was identified as the main source of stress which included relationships at work and demands of the job. Hospital nurses experiencing high work stress were more likely to use professional support and personal coping (discuss problems with friends/family, have a good cry and eat more) than others. Nurses believed in the importance of health promotion as part of their work; however, qualified nurses felt more confident and gave more health related information than student nurses. Student nurses perceived a lower risk of contacting AIDS through work and a higher concern/worry in caring for AIDS patients than qualified nurses.  相似文献   

15.
Spatial learning and memory were studied in dogs of varying ages and sources. Compared to young dogs, a significantly higher proportion of aged dogs could not acquire a spatial delayed nonmatching-to-sample task. A regression analysis revealed a significant age effect during acquisition. Spatial memory was studied by comparing performance at delay intervals of 20, 70, and 110 s. At short delays aged and young dogs were similar; at longer delays, errors increased to a greater extent in old than in young dogs; however, this was not statistically significant. It was possible to identify 2 groups of aged animals, age-impaired and age-unimpaired. Several of the dogs were also tested on an object recognition memory task, which was more difficult to learn than the spatial task. The possibility that these findings are confounded by breed differences is considered. Overall, the present results provide further evidence of the value of a canine model of aging. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
Research has shown the importance of employee age relative to coworker age in determining attitudes, performance, and career-related opportunities. The authors used chronological and subjective measures of employee and manager age to determine whether employee age relative to the manager has an impact on these same outcome variables. One hundred eighty-five managers and 290 employees completed surveys. The strongest and most consistent age effects were observed for interactions between employee and manager chronological age. Both the magnitude and pattern of the employee-manager age interactions varied by self- and manager-rated outcome measures of work attitudes, performance and promotability assessments, and developmental experiences. Results are discussed in light of the relational demography and career timetable literatures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
Extending Freud's formulation with regard to the nature of the primary process, it was posited that language should reflect Freud's content that "contraries are not kept apart from each other, but are treated as though they were identical." Hypothesizing that secondary process thinking is a function of development, 3rd graders and 6th graders were compared on the basis of a paper-and-pencil test wherein the task was to select a synonym word from a group containing the synonym, an antonym, and an irrelevant word. Primary process thinking, as measured above, was found to be more characteristic of the younger group. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
4 measures of visual perceptual suggestibility were obtained on a sample of 290 school children in Grades 1-12. Suggestibility was found to decrease with increasing chronological age. The relationship was significant and curvilinear (p = .001). In order of influence on the children the 4 measures of suggestion could be ranked as follows: prestige suggestion with ambiguous stimuli; conformity suggestion with ambiguous stimuli; prestige suggestion with unambiguous stimuli; baseline or selfsuggestion (p = .001). No sex differences were found. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
BACKGROUND: To analyze the response to eradicative therapy and prognostic factors in 52 patients with primary gastrointestinal lymphoma (PGIL) diagnosed at a single institution in a 13 year period. PATIENTS AND METHODS: The main clinical, biological and evolutive data were recorded. Pathologic diagnosis of PGIL was made according to the Working Formulation. Clinical stage was determined by the Ann Arbor system modified by Mushoff. The results of therapy as well as the influence of such characteristics on complete remission (CR), disease-free survival (DFS) and overall survival (OS) were studied. RESULTS: Mean age of the series was 53 years (SD 15). Thirty patients were males. HIV infection preceded PGIL diagnosis in 10 cases. Seventeen had bad performance status (ECOG 2-4) and 30 B symptoms. The PGIL localization was gastric in 31 cases and 29 had a low grade malignant lymphoma. B phenotype was demonstrated in 98% and 22 patients presented advanced stages (IIE2-IV). Treatment was radical surgery followed by intensive chemotherapy in 32 cases, intensive chemotherapy alone in 17, and surgical resection in 3. CR was obtained in 34 patients and 6 of them relapsed. The projected DFS from CR at 9 years was 72% and OS was 26%. CR and survival were not influenced by PGIL localization and treatment type. The main unfavourable prognostic factors were advanced stage (CR and OS), B symptoms (DFS and OS) and advanced ECOG score (CR, DFS and OS). Previous HIV infection had an independent prognostic influence on both CR and OS. CONCLUSIONS: In patients with PGIL, the achievement of CR, DFS and survival have been independent of the type of eradicative treatment used. Performance status, B symptoms and clinical stage have been the main prognostic factors. HIV infection carried an independent prognostic significance.  相似文献   

20.
The assessment of psychopathy was examined as a function of age in 889 male prison inmates between the ages of 16 and 69. Ratings of psychopathy were made with the Psychopathy Checklist (PCL), which measures 2 correlated factors. Factor 1 describes a cluster of affective-interpersonal traits central to psychopathy. Factor 2 describes traits and behaviors associated with an unstable, unsocialized lifestyle, or social deviance. Cross-sectional analyses revealed that mean scores on Factor 1 were stable across the age-span; mean scores on Factor 2 declined with age. The prevalence of antisocial personality disorder, and, to a lesser extent of PCL-defined psychopathy, also declined with age. The results are consistent with a conceptualization of psychopathy as encompassing 2 correlated but distinct constructs. They also suggest that age-related differences in traits related to impulsivity, social deviance, and antisocial behavior are not necessarily paralleled by differences in the egocentric, manipulative, and callous traits fundamental to psychopathy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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