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1.
The social environment affects both behavioral and physiological responses to separation from the mother. Less information is available on the impact of the social environment on the response to separation in peer-reared infant monkeys. This study reports the responses of peer-reared pigtail macaque infants to repeated separations, and the impact of social versus isolation housing during the separation. The responses of two pairs of monkeys were studied during four three-day separations. One of each pair was housed in isolation during the separation, and the other was with another pair of peers, with whom they had been living for one month prior to the separation. The isolation-housed peer responded to the separation with behavioral agitation, but no depression. The socially-housed peer's behavior did not differ from baseline during the separation. During successive reunions, all the separated monkeys, regardless of housing condition, exhibited declining levels of behaviors related to maintaining proximity to their attachment figure. Although the number of subjects is small, the results suggest that the presence of social support, in the form of a familiar peer, can ameliorate the response to separation, and that with repeated separations the responses of the monkeys changes significantly.  相似文献   
2.
3.
Molecular Biology Reports - Serotoninergic system is one of the most important neurotransmission systems investigated in the field of psychiatry. Extensive evidence reveals how alterations of this...  相似文献   
4.

Pearl millet downy mildew (DM) incidence, severity and yield losses of two pearl millet varieties (local and improved) due to the disease were determined in the field. Significant differences in the disease incidence and severity were recorded in the plots sown with metalaxyl-treated seeds and those sown with non-treated seeds, indicating the efficacy of the fungicide on the fungus. Yield losses due to non-treatment of seeds with metalaxyl was 40.88 and 45.39% in a local variety and 43.00 and 18.60% in an improved variety in the 2000 and 2001 cropping seasons respectively. Significant differences between plots sown with metalaxyl-treated and those sown with non-treated seeds were obtained for other yield components such as 1000-grains weight, panicle length and weight.  相似文献   
5.

Background  

Organisms are capable of developing different phenotypes by altering the genes they express. This phenotypic plasticity provides a means for species to respond effectively to environmental conditions. One of the most dramatic examples of phenotypic plasticity occurs in the highly social hymenopteran insects (ants, social bees, and social wasps), where distinct castes and sexes all arise from the same genes. To elucidate how variation in patterns of gene expression affects phenotypic variation, we conducted a study to simultaneously address the influence of developmental stage, sex, and caste on patterns of gene expression in Vespula wasps. Furthermore, we compared the patterns found in this species to those found in other taxa in order to investigate how variation in gene expression leads to phenotypic evolution.  相似文献   
6.
Many studies would appear to support an important relationship between behavior and the regulation of the immune response, at the core of the developing field of psychoneuroimmunology (PNI). However, wide variations are noted in the strength of this relationship, even for the same species under very similar circumstances. The present paper reviews work from our laboratory in both young and adult pigtail and bonnet macaques describing the ranges of variability in both behavioral and immunological responses to social separation and social conflict. It is shown that the magnitude of immune changes that follow a social stressor often covary with the magnitude of the behavioral changes that are observed. Second, there is support for the observation that there are specific behaviors such as social affiliation that may mitigate untoward behavioral and immunological consequences of social stressors. Finally, studies are reviewed which suggest that assessment of autonomic reactivity as reflected in cardiovascular regulation might provide an important clue to the relative risk for immune modulation under challenge. © 1996 Wiley-Liss, Inc.  相似文献   
7.
Vascular endothelial growth factor (VEGF), an angiogenic factor produced in response to ischemic injury, promotes vascular permeability (VP). Evidence is provided that Src kinase regulates VEGF-mediated VP in the brain following stroke and that suppression of Src activity decreases VP thereby minimizing brain injury. Mice lacking pp60c-src are resistant to VEGF-induced VP and show decreased infarct volumes after stroke whereas mice deficient in pp59c-fyn, another Src family member, have normal VEGF-mediated VP and infarct size. Systemic application of a Src-inhibitor given up to six hours following stroke suppressed VP protecting wild-type mice from ischemia-induced brain damage without influencing VEGF expression. This was associated with reduced edema, improved cerebral perfusion and decreased infarct volume 24 hours after injury as measured by magnetic resonance imaging and histological analysis. Thus, Src represents a key intermediate and novel therapeutic target in the pathophysiology of cerebral ischemia where it appears to regulate neuronal damage by influencing VEGF-mediated VP.  相似文献   
8.

Objective

To evaluate the safety and efficacy as a tool of smoking cessation of electronic cigarettes (e-cigarettes), directly comparing users of e-cigarettes only, smokers of tobacco cigarettes only, and smokers of both.

Design

Prospective cohort study. Final results are expected in 2019, but given the urgency of data to support policies on electronic smoking, we report the results of the 12-month follow-up.

Data Sources

Direct contact and structured questionnaires by phone or via internet.

Methods

Adults (30–75 years) were included if they were smokers of ≥1 tobacco cigarette/day (tobacco smokers), users of any type of e-cigarettes, inhaling ≥50 puffs weekly (e-smokers), or smokers of both tobacco and e-cigarettes (dual smokers). Carbon monoxide levels were tested in a sample of those declaring tobacco smoking abstinence.

Main Outcome Measures

Sustained smoking abstinence from tobacco smoking at 12 months, reduction in the number of tobacco cigarettes smoked daily.

Data Synthesis

We used linear and logistic regression, with region as cluster unit.

Results

Follow-up data were available for 236 e-smokers, 491 tobacco smokers, and 232 dual smokers (overall response rate 70.8%). All e-smokers were tobacco ex-smokers. At 12 months, 61.9% of the e-smokers were still abstinent from tobacco smoking; 20.6% of the tobacco smokers and 22.0% of the dual smokers achieved tobacco abstinence. Adjusting for potential confounders, tobacco smoking abstinence or cessation remained significantly more likely among e-smokers (adjusted OR 5.19; 95% CI: 3.35–8.02), whereas adding e-cigarettes to tobacco smoking did not enhance the likelihood of quitting tobacco and did not reduce tobacco cigarette consumption. E-smokers showed a minimal but significantly higher increase in self-rated health than other smokers. Non significant differences were found in self-reported serious adverse events (eleven overall).

Conclusions

Adding e-cigarettes to tobacco smoking did not facilitate smoking cessation or reduction. If e-cigarette safety will be confirmed, however, the use of e-cigarettes alone may facilitate quitters remaining so.

Registration Number

NCT01785537.  相似文献   
9.
Postnatal development changes in mechanisms of synaptosomal amino acid transport have been studied in rat cerebral cortex. Specific uptake of radiolabeled l-serine was examined and compared with that of radiolabeled GABA using synaptosomes-enriched fractions freshly prepared from cerebral cortex at different postnatal days from the birth to young adulthood. The preparations were incubated with 10 nM of [3H]l-serine and 10 nM of [3H]-GABA in either the presence or absence of NaCl, KCl or choline chloride, at 2 and 30 °C, for different periods up to 30 min. The uptake of [3H]l-serine was temperature dependent in synaptosomal fractions prepared from cerebral cortex of rats in postnatal days 5, 7, 13 and 21, but stronger dependence was observed in adult brain, irrespective of the presence of Na+, K+ or choline ions. At all postnatal ages studied, [3H]-GABA uptake showed a high activity in the presence of Na+ ions and at 30 °C. The values of Km were 90–489 μM in l-serine uptake. However, in the uptake of GABA the values of Km were 80–150 μM. The highest values of Vmax were obtained at 5 and 21 postnatal days for both transport systems. These results indicate that the uptake of l-serine and GABA are regulated differentially during postnatal development.  相似文献   
10.
Resource availability or distribution may affect interindividual competition in species such as primates, which forage in social groups, and several field studies suggest that dominance status predicts access to restricted food sources. Increased competition due to restricted resources may result in the intensification of aggressive behaviors. The study reported here examines the impact of manipulation of the distribution of food resources in a laboratory-housed group of bonnet macaques to assess the impact of distribution on aggressive behaviors. Food was restricted to a space which allowed access to only one or two individuals at a time or was dispersed throughout the living enclosure to allow universal access in alternating periods. During periods of clumped distribution, the monkeys obtained access to the food in order of their dominance status in the group. In addition, overall levels of aggressive behaviors increased, submissive behavior increased, and play decreased during periods of clumped distribution of food. These results confirm the findings from field studies indicating increases in agonism with restriction of food resources. These findings also have implications for primate colony management, in terms of developing strategies for minimizing intragroup aggression in captive groups.  相似文献   
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