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41.
Sakae DY Pereira LO da Cunha IC de Lima TC Paschoalini MA Faria MS 《Neurobiology of learning and memory》2008,90(2):455-459
The aim of the present study was to evaluate the occurrence of fear sensitization in rats previously treated with an inhibitor of the NO syntheses and submitted to Trial1/Trial2 plus-maze (PM) procedure. Male Wistar rats received a systemic treatment with N(omega)-nitro-L-Arginine-methyl ester (L-NAME; 5, 10 or 50 mg kg(-1)) and were submitted to PM Trial1. In the following day the animals were re-exposed to the PM with no drug administration (Trial2). Some standards spatial-temporal measures, such as the percentage of entries (% Open arm entries) and time spent (% Open arm time) in the open arms and risk assessment frequency were recorded and used to estimate the animal level of fear sensitization in PM Trial2. The results showed that animals receiving L-NAME (50 mg kg(-1)) displayed increased % Open arm entries and % Open arm time in Trial2 in relation to the group receiving 0.9% saline, which is compatible with impaired fear/anxiety acquisition during Trial1/Trial2 PM procedure. In addition, rats treated with L-NAME (50 mg kg(-1)) exhibited low level of risk assessment in Trial2 in relation to the group treated with 0.9% saline, which indicates low level of fear/anxiety during PM re-exposure. The number of entries into the enclosed arms was not changed by any L-NAME treatment, which suggests no bias of the drug treatments on animal locomotor activity. The data suggest that NO synthesis may mediate the fear sensitization process in the PM. 相似文献
42.
Stephanie P da Silva Megan E Maxwell Kennon A Lattal 《Journal of the experimental analysis of behavior》2008,90(3):313-331
The contribution of past experiences to concurrent resurgence was investigated in three experiments. In Experiment 1, resurgence was related to the length of reinforcement history as well as the reinforcement schedule that previously maintained responding. Specifically, more resurgence occurred when key pecks had been reinforced on a variable-interval 1-min schedule than a variable-interval 6-min schedule, but this effect may have been due either to the differential reinforcement rates or differential response rates under the two schedules. When reinforcement rates were similar (Experiment 2), there was more resurgence of high-rate than low-rate responding. When response rates were similar (Experiment 3), resurgence was not related systematically to prior reinforcement rates. Taken together, these three experimental tests of concurrent resurgence illustrate that prior response rates are better predictors of resurgence than are prior reinforcement rates. 相似文献
43.
Ebenézer A. de Oliveira Fernando C. Barros Luciana D. da Silva Anselmi Cesar A. Piccinini 《Journal of child and family studies》2006,15(5):631-642
Based on Bronfenbrenner's (1999) ecological perspective, a longitudinal, prospective model of individual differences in the quality of home environment (Home Observation for Measurement of the Environment—HOME) was tested in a sample of 179 Brazilian children and their families. Perinatal measures of family socioeconomic status (SES) and child birth weight had direct effects on HOME at preschool age. As either family SES or child birth weight increased, HOME also increased through diminished emotional distress in the mother a month following childbirth. SES had a negative effect on number of children in the household, which in turn had a long-term negative impact on HOME. Compared to mothers who had reported not to plan their pregnancy, those who did were more likely to have fewer children, to report more spouse support during childbearing, and to show less emotional distress a month after childbirth, all of which also influenced HOME at preschool age. These findings are discussed in light of the broader socio-ecological Brazilian context, with direct implications to clinical practice aimed at improving the quality of home environment. 相似文献
44.
Palmero EI Ashton-Prolla P da Rocha JC Vargas FR Kalakun L Blom MB Azevedo SJ Caleffi M Giugliani R Schüler-Faccini L 《Journal of genetic counseling》2007,16(3):363-371
Hereditary breast cancer (HBC) accounts for 5–10% of breast cancer cases and it significantly increases the lifetime risk
of cancer. Our objective was to evaluate the sociodemographic variables, family history of cancer, breast cancer (BC) screening
practices and the risk profile of cancer affected or asymptomatic at-risk women that undergo genetic counseling for hereditary
breast cancer in public Brazilian cancer genetics services. Estimated lifetime risk of BC was calculated for asymptomatic
women using the Gail and Claus models. The majority of women showed a moderate lifetime risk of developing BC, with an average
risk of 19.7% and 19.9% by the Gail and Claus models, respectively. The average prior probability of carrying a BRCA1/2 gene mutation was 16.7% and overall only 32% fulfilled criteria for a hereditary breast cancer syndrome as assessed by family
history. We conclude that a significant number of individuals at high-risk for HBC syndromes may not have access to the benefits
of cancer genetic counseling in these centers. Contributing factors may include insufficient training of healthcare professionals,
disinformation of cancer patients; difficult access to genetic testing and/or resistance in seeking such services. The identification
and understanding of these barriers is essential to develop specific strategies to effectively achieve cancer risk reduction
in this and other countries were clinical cancer genetics is not yet fully established. 相似文献
45.
46.
We present some recent technical results of us on the incompleteness of classical analysis and then discuss our work on the Arnol'd decision problems for the stability of fixed points of dynamical systems.Partially supported by FAPESP and CNPq (Brazil, Philosophy Section). 相似文献
47.
Marin BV Marin G Padilla AM De La Rocha C Fay J 《Hispanic journal of behavioral sciences》1982,3(3):257-273
An archival study was done of 500 medical records from a community clinic serving a low income predominantly Hispanic area of Los Angeles. The data collected included demographic characteristics and presented symptoms or reasons for visit, as well as diagnosis and treatment. The greatest number of patient visits were made for family planning services. A large porportion of the patients who received initial family planning services failed to return to the clinic for follow ups or additional supplies. A total of 208 pregnancy tests were performed in 151 of the 500 cases sampled. Of these, 152 were positive. The most frequently stated reason for requesting pediatric services was for physical exams, accounting for 30% of the visits. It should be noted that the discontinuity of care and insufficient utilization of preventive care seen in these results deserve serious attention by medical clinic administrators. The rate of patients who do not return for family planning after the initial visit is worrisome. A greater effort to attract women to family planning services at the time they request pregnancy verification could reduce the need for abortion of unwanted pregnancy. The data also indicate that changes in the wording of certain questions commonly asked of clients may be needed. This study allowed service providers to obtain important information about their performance, their needs, and the future direction that their services might take. This type of analysis is relatively low in cost and can yield important benefits, espicially if done on a periodical base in a search for policy implications. 相似文献
48.
Studies in East European Thought - That which connects ethics and epistemology is the concept of truth. The threads concerned with the ethical and epistemological understanding of truth are... 相似文献
49.
Benetti F da Silveira CK da Silva WC Cammarota M Izquierdo I 《Neurobiology of learning and memory》2012,97(1):54-58
Early partial maternal deprivation causes long-lasting neurochemical, behavioral and brain structural effects. In rats, it causes a deficit in memory consolidation visible in adult life. Some of these deficits can be reversed by donepezil and galantamine, which suggests that they may result from an impairment of brain cholinergic transmission. One such deficit, representative of all others, is an impairment of memory consolidation, clearly observable in a one-trial inhibitory avoidance task. Recent data suggest a role of brain histaminergic systems in the regulation of behavior, particularly inhibitory avoidance learning. Here we investigate whether histamine itself, its analog SKF-91844, or various receptor-selective histamine agonists and antagonists given into the CA1 region of the hippocampus immediately post-training can affect retention of one-trial inhibitory avoidance in rats submitted to early postnatal maternal deprivation. We found that histamine, SKF-91844 and the H2 receptor agonist, dimaprit enhance consolidation on their own and reverse the consolidation deficit induced by maternal deprivation. The enhancing effect of histamine was blocked by the H2 receptor antagonist, ranitidine, but not by the H1 receptor antagonist pyrilamine or by the H3 antagonist thioperamide given into CA1 at doses known to have other behavioral actions, without altering locomotor and exploratory activity or the anxiety state of the animals. The present results suggest that the memory deficit induced by early postnatal maternal deprivation in rats may in part be due to an impairment of histamine mediated mechanisms in the CA1 region of the rat hippocampus. 相似文献
50.