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891.
Wang YJ Lu J Wu DM Zheng ZH Zheng YL Wang XH Ruan J Sun X Shan Q Zhang ZF 《Neurobiology of learning and memory》2011,96(2):156-165
Evidence indicates that systemic administration of lipopolysaccharide (LPS) induces brain inflammation, ultimately resulting in cognitive deficits. Ursolic acid (UA), a plant-derived pentacyclic triterpenoid, is well known to possess multiple biological functions, including antioxidant, anti-tumor and anti-inflammatory activities. In the present study, we assessed the protective effect of UA against the LPS-induced cognitive deficits in mice. We found that UA significantly improved cognitive deficits of LPS-treated mice in open field, step-through passive avoidance and Morris water maze tasks. One potential mechanism of this action was attributed to the decreased production of pro-inflammatory markers including COX-2, iNOS, TNF-α, IL-1β, IL-2 and IL-6 in LPS-treated mouse brain. Mechanistically, UA markedly inhibited LPS-induced IκBα phosphorylation and degradation, NF-κB p65 nuclear translocation and p38 activation in mouse brain, but did not affect the activation of TLR4, MyD88, ERK, JNK and Akt. Taken together, these results suggest that UA may be useful for mitigating inflammation-associated brain disorders by inhibiting pro-inflammatory factors production, at least in part, through blocking the p38/NF-κB signaling pathways. 相似文献
892.
Conde-Guzón PA Bartolomé-Albistegui MT Quirós P Cabestrero R 《The Spanish journal of psychology》2011,14(2):600-607
This paper examines the association of cardiovascular reactivity with thermal thresholds (detection and unpleasantness). Heart period (HP), systolic (SBP) and diastolic (DBP) blood pressure of 42 health young males were recorded during a cardiovascular reactivity task (a videogame based upon Sidman's avoidance paradigm). Thermal sensitivity, assessing detection and unpleasantness thresholds with radiant heat in the forearm was also estimated for participants. Participants with differential scores in the cardiovascular variables from base line to task > or = P65 were considered as reactors and those how have differential scores < or = P35 were considered as non-reactors. Significant differences were observed between groups in the unpleasantness thresholds in blood pressure (BP) but not in HP. Reactors exhibited significant higher unpleasantness thresholds than non-reactors. No significant differences were obtained in detection thresholds between groups. 相似文献
893.
Torres B Alonso-Arbiol I Cantero MJ Abubakar A 《The Spanish journal of psychology》2011,14(2):630-638
The quality of infant-mother attachment has been linked to competence in different domains of child development. Research indicates that early intervention can enhance the quality of infant-mother attachment, though its efficacy in a group format has yet to be evaluated. The current study is aimed at examining the usefulness of a group intervention in enhancing infant-mother attachment. An intervention aimed at addressing aspects such as maternal responsivity, sensitivity and childrearing behaviour was developed by the researchers and experienced psychologists. The intervention spanned a period of 14 months starting from the third quarter of pregnancy. The intervention was evaluated among 24 mothers from the Basque region of Spain. The sample consisted of children of both genders in a similar proportion: 45.8% were boys and 54.2% were girls. The children in this sample were full-term born and did not present symptoms of any serious pre- or postnatal complications. The intervention had a statistically non-significant medium effect. Infants whose mothers had received the intervention showed higher rates of secure attachment compared to children from the control group, as assessed by the Strange Situation observation procedure. A potentially significant confounding variable, maternal attachment, was balanced across the intervention and comparison groups. We can tentatively point out that a group intervention may enhance the quality of infant-mother attachment. Nevertheless, because the study design was not randomized, the results of this study remain preliminary and need replication in a full randomized controlled trial designed study. 相似文献
894.
The reading achievement of children and adolescents with Attention Deficit Hyperactivity Disorder (ADHD) has scarcely been explored in research conducted in the Spanish language and when it has, the results have been contradictory. The focus of the present research is to analyze participants' reading competency and metacognitive strategies as they carry out reading comprehension tasks. The sample was comprised of 187 Argentine schoolchildren aged 9 to 13 years old. 94 constituted the control group and the clinical group consisted of 93 schoolchildren diagnosed with ADHD. The metacognitive assessment was made up of two metacognitive tests, the Reading Awareness Scale (ESCOLA; acronym in Spanish) and a Spanish adaptation of Metacognitive Awareness of Reading Strategies Inventory (MARSI), and one test of reading comprehension, the Evaluation of Reading Processes for Secondary Education Students (PROLEC-SE; acronym in Spanish). Students with ADHD had lower achievement on tests o reading comprehension compared to the control group. Nevertheless, our results suggest their difficulties did not stem from readin comprehension problems, but rather from alterations in their Executive Functions, because when subjects' reading comprehensio was equalized, students with ADHD still exhibited a lower level of Metacognition, particularly when it came to planning. 相似文献
895.
896.
Menopause is associated with a considerable variety of physical, psychological and social symptoms that can be treated using cognitive-behavioral techniques. In the present study, 21 women took part in an eight-week group intervention consisting of weekly two-hour sessions to address their slight symptoms related to the climacteric stage of life. The intervention included: psycho education on menopause, relaxation techniques, nutrition and fitness exercises, Kegel exercises, and problem-solving techniques. A control group was included that did not receive treatment and consisted of 28 women. The results revealed a significant reduction in most symptoms (including depression and anxiety) after intervention as compared to the baseline period. No changes appeared in the control group. The relevance of this work lies in the potential element of prevention this therapeutic package could offer to relieve various symptoms, slight and incipient, during the perimenopausal stage. 相似文献
897.
Ruiz Hernández JA Torrente Hernández G Rodríguez González A Ramírez de la Fe Mdel C 《The Spanish journal of psychology》2011,14(1):227-236
The aim of this paper was to develop an instrument to assess levels of stress experienced by Latin-American immigrants in their acculturative process in Spain. A sample of 692 immigrants from Latin America, aged 20 to 63 years, took part on this study (54.9% males and 45.1% females). A 24-item questionnaire with high reliability (.92) was elaborated. Six factors related to acculturative stress were found: 1) discrimination and rejection; 2) differences with the out-group (native Spaniards); 3) citizenship problems and legality; 4) problems concerning social relationships with other immigrants; 5) nostalgia and longing; and 6) family break-up. Our findings show that participants have a high level of stress related to nostalgia and longing, family break-up, and the perception of discrimination and rejection by natives. The usefulness of the instrument and its applications and restrictions are discussed. 相似文献
898.
The purpose of this paper is to analyse the Spanish mobile phone industry to determine how mobile phone companies and certain
institutions can improve protection for children who use mobile phones. We carried out a multivariate statistical analysis
using anonymous primary data from mobile phone companies, and institutions and associations that protect children, to compare
these stakeholders’ opinions and to put forward solutions. We proved that, even though some European countries have made an
effort to provide safer ICT services, all stakeholders still need to cooperate and agree on solutions to the commercial problems
associated with children using mobile phones. This can be done by signing codes of conduct. We found that even though some
companies implement measures to protect children from accessing harmful content via their mobile phones, they do so for reasons
of legal and not social responsibility. 相似文献
899.
Great apes can use multiple tools to extract food embedded in substrates and can invent new ways to exploit those resources.
We tested five bonobos, five chimpanzees, and six orangutans in a task in which they had to use (and modify) a tool as a straw
to drink the juice located inside a container. Experiment 1 showed that four orangutans and one chimpanzee invented the use
of a piece of electric cable to get the juice. Experiment 2 investigated whether subjects could transform a non-functional
hose into a functional one by removing blockages that impeded the free flow of juice. Orangutans outperformed chimpanzees
and bonobos by differentially removing those blockages that prevented the flow of juice, often doing so before attempting
to extract the juice. In Experiment 3, we presented chimpanzees and orangutans with four 3-tool sets (each tool set contained
a single straw-like tool) and allowed them to select one tool. Unlike chimpanzees, orangutans succeeded in selecting the straw-like
tool above chance levels without having to physically manipulate it. We suggest that orangutans’ superior performance is related
to their greater reliance on mouth actions during foraging. Experiment 4 investigated whether orangutans were also capable
of selecting the suitable tool not by its appearance, but by the effects that it produced. After witnessing the experimenter
blow bubbles or absorb liquid with a functional tool but fail to accomplish the same thing with the non-functional tool, orangutans
failed to select the functional tool above chance levels. 相似文献
900.
Wild capuchin monkeys select stone tools to crack open nuts on the basis of their weight and friability, two non-visual functional
properties. Here, we investigated whether they would select new stick-like tools on the basis of their rigidity. In Experiment
1, subjects faced an out-of-reach reward and a choice of three unfamiliar tools differing in color, diameter, material, and
rigidity. In order to retrieve the reward, capuchins needed to select the rigid tool exemplar. Capuchins gathered information
regarding tools’ pliability either by (1) manipulating the tools themselves (manipulation condition), (2) observing a human
demonstrator repeatedly bending the tools (observation condition), or (3) seeing the tools placed on a platform without any
manipulation taking place (visual static condition). Subjects selected the rigid tool above chance levels in both the manipulation
and observation conditions, but not in the visual static condition. In Experiment 2, subjects needed to select and use a flexible
tool to access a liquid reward (as opposed to the rigid tool, as in previous experiment). Again, capuchins selected above
chance levels the appropriate tool (i.e., flexible), thus demonstrating a good appreciation of the relation between the tool
properties and the task requirements. 相似文献