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71.
72.
The medial preoptic area (MPOA) is an integral site for male sexual behavior. Dopamine is released in the MPOA before and during copulation and facilitates male rat sexual behavior. Repeated sexual experience and noncopulatory exposures to an estrous female facilitate subsequent copulation. However, the neurobiological mechanisms that mediate such enhancement remain unclear. Here, we examined the role of dopamine D? receptors in the MPOA in experience-induced enhancement of male sexual behavior in rats. In experiment 1, microinjections of the D? antagonist SCH-23390 into the MPOA before each of seven daily 30-min noncopulatory exposures to a receptive female impaired copulation on a drug-free test on Day 8, compared to vehicle-treated female-exposed animals. Copulatory performance in drug-treated animals was similar to that of vehicle-treated males that had not been preexposed to females. This effect was site specific. There were no group differences in locomotor activity in an open field on the copulation test day. In experiment 2, a separate cohort of animals was used to examine phosphorylation of dopamine- and cAMP-regulated phosphoprotein (DARPP-32) in the MPOA of animals with acute and/or chronic sexual experience. DARPP-32 is a downstream marker of D? receptor signaling and substrate of cAMP-dependent protein kinase (PKA). Western immunoblot analysis revealed that p-DARPP-32 expression was greatest in the MPOA of males that received both acute and chronic sexual experience, compared to all other mated conditions and na?ve controls. These data suggest that D? receptors in the MPOA contribute to experience-induced enhancement of male sexual behavior, perhaps through a PKA regulated mechanism. 相似文献
73.
Fernandez-Luque L Karlsen R Melton GB 《Journal of medical Internet research》2012,14(1):e22-Feb;14(1):e22
Background
Social media are becoming mainstream in the health domain. Despite the large volume of accurate and trustworthy health information available on social media platforms, finding good-quality health information can be difficult. Misleading health information can often be popular (eg, antivaccination videos) and therefore highly rated by general search engines. We believe that community wisdom about the quality of health information can be harnessed to help create tools for retrieving good-quality social media content.Objectives
To explore approaches for extracting metrics about authoritativeness in online health communities and how these metrics positively correlate with the quality of the content.Methods
We designed a metric, called HealthTrust, that estimates the trustworthiness of social media content (eg, blog posts or videos) in a health community. The HealthTrust metric calculates reputation in an online health community based on link analysis. We used the metric to retrieve YouTube videos and channels about diabetes. In two different experiments, health consumers provided 427 ratings of 17 videos and professionals gave 162 ratings of 23 videos. In addition, two professionals reviewed 30 diabetes channels.Results
HealthTrust may be used for retrieving online videos on diabetes, since it performed better than YouTube Search in most cases. Overall, of 20 potential channels, HealthTrust’s filtering allowed only 3 bad channels (15%) versus 8 (40%) on the YouTube list. Misleading and graphic videos (eg, featuring amputations) were more commonly found by YouTube Search than by searches based on HealthTrust. However, some videos from trusted sources had low HealthTrust scores, mostly from general health content providers, and therefore not highly connected in the diabetes community. When comparing video ratings from our reviewers, we found that HealthTrust achieved a positive and statistically significant correlation with professionals (Pearson r 10 = .65, P = .02) and a trend toward significance with health consumers (r 7 = .65, P = .06) with videos on hemoglobinA1 c, but it did not perform as well with diabetic foot videos.Conclusions
The trust-based metric HealthTrust showed promising results when used to retrieve diabetes content from YouTube. Our research indicates that social network analysis may be used to identify trustworthy social media in health communities. 相似文献74.
Damond F Benard A Balotta C Böni J Cotten M Duque V Ferns B Garson J Gomes P Gonçalves F Gottlieb G Kupfer B Ruelle J Rodes B Soriano V Wainberg M Taieb A Matheron S Chene G Brun-Vezinet F;ACHI 《Journal of clinical microbiology》2011,49(10):3491-3497
Accurate HIV-2 plasma viral load quantification is crucial for adequate HIV-2 patient management and for the proper conduct of clinical trials and international cohort collaborations. This study compared the homogeneity of HIV-2 RNA quantification when using HIV-2 assays from ACHI(E)V(2E) study sites and either in-house PCR calibration standards or common viral load standards supplied to all collaborators. Each of the 12 participating laboratories quantified blinded HIV-2 samples, using its own HIV-2 viral load assay and standard as well as centrally validated and distributed common HIV-2 group A and B standards (http://www.hiv.lanl.gov/content/sequence/HelpDocs/subtypes-more.html). Aliquots of HIV-2 group A and B strains, each at 2 theoretical concentrations (2.7 and 3.7 log(10) copies/ml), were tested. Intralaboratory, interlaboratory, and overall variances of quantification results obtained with both standards were compared using F tests. For HIV-2 group A quantifications, overall and interlaboratory and/or intralaboratory variances were significantly lower when using the common standard than when using in-house standards at the concentration levels of 2.7 log(10) copies/ml and 3.7 log(10) copies/ml, respectively. For HIV-2 group B, a high heterogeneity was observed and the variances did not differ according to the type of standard used. In this international collaboration, the use of a common standard improved the homogeneity of HIV-2 group A RNA quantification only. The diversity of HIV-2 group B, particularly in PCR primer-binding regions, may explain the heterogeneity in quantification of this strain. Development of a validated HIV-2 viral load assay that accurately quantifies distinct circulating strains is needed. 相似文献
75.
76.
Van Bever HP Llanora G 《Asian Pacific journal of allergy and immunology / launched by the Allergy and Immunology Society of Thailand》2011,29(1):15-24
Eczema or atopic dermatitis (AD) is the most common skin disease in children, and recent data derived from several studies showed that the prevalence of AD is still increasing in most Asian countries. The role of allergic reactions in AD is still a matter of debate. In some children allergy is not involved, while in others allergic reactions can trigger and maintain the skin lesions. Therefore, AD is now considered as a group of skin diseases with as a common feature the existence of a chronic skin inflammation. The underlying mechanisms of AD are not uniform, but differ from patient to patient, and also differ in one patient in time, suggesting the existence of different subtypes of AD, in a complex interplay. From different studies it is now suggested that at least 4 different players are involved in AD. These 4 players are: congenital skin barrier defects, allergy, autoimmunity (i.e. the production of autoantibodies against skin cells), and microbial agent colonization, especially colonization with bacteria, mainly Staphylococcus aureus. Much more needs to be discovered on the mechanisms of AD and other "players" might be discovered soon, as the current "4-player-model" cannot explain all features of AD. Treatment of AD might change in the near future. Today's cornerstones of treatment are still moisturizers (from a young age to prevent further skin barrier dysfunctions and allergic sensitization), local corticosteroids, and antiseptics, but new future therapeutic approaches become very likely. 相似文献
77.
Genevieve K. Lennox Mitchell Clark Tiffany Zigras Marjan Rouzbahman Guangming Han Marcus Q. Bernardini Lilian T. Gien 《Journal d'obstetrique et gynecologie du Canada》2021,43(5):564-570
ObjectiveCompare recurrence-free survival (RFS) and morbidity between radical hysterectomy (RH) and simple hysterectomy (SH) for clinically diagnosed stage II endometrial cancer.MethodsA multicentre, retrospective study, from 2000 to 2015, involving patients with endometrial cancer with cervical involvement preoperatively and stromal invasion on final pathology. Wilcoxon rank-sum test, Fisher exact test, Kaplan-Meier survival functions, and Cox proportional hazards models were used for analysis.ResultsNinety of 1613 patients had clinical stage II endometrial cancer; 57 underwent RH and 33 underwent SH, with no difference in adjuvant treatment or morbidity. About half of patients (51%) had pathologic stage III–IV disease. Mean follow-up was 3.3 and 3.8 years for SH and RH, respectively. Thirty-three percent of patients with RH and SH experienced a recurrence. Most recurrences were distant: 90% with SH and 79% with RH. There was no difference in RFS between groups (2-year: SH 65% vs. RH 75%; 5-year: SH 54% vs. RH 63%; P = 0.72). Controlling for stage, adjuvant treatment, and margin status, RH was not associated with RFS (HR 0.62; 95% CI 0.28–1.35). Among 44 patients with pathologic stage II disease, 7 had a recurrence (4 SH and 3 RH); 6 of 7 had distant recurrences.ConclusionsFifty-one percent of patients with clinical stage II endometrial cancer had advanced disease on final pathology, highlighting the importance of surgical staging. RH was not associated with RFS or reduced morbidity. Most recurrences were distant. Although RH could be performed to achieve negative surgical margins, SH may be sufficient for central, small tumours given the high risk of advanced disease and distant recurrence. Research efforts should further elucidate the ideal management of these patients. 相似文献
78.
Neuropsychological research and practice rely on cognitive task performance measures as indicators of brain functioning. The neural activity underlying stimulus‐response processes can be assessed with ERPs, but the relations between these cognitive processes and the brain's intrinsic resting state EEG activity are less understood. This study focused on the neurocognitive functioning of 20 healthy young adults in an equiprobable go/no‐go task to map the ERP correlates of behavioral responses and examine contributions of the resting state intrinsic EEG to task‐related outcomes. Continuous EEG was recorded during pretask eyes‐closed (EC) and eyes‐open (EO) conditions, and in the subsequent task. Delta, theta, alpha, and beta band amplitudes were assessed for the EC state and also for the reactive change to EO. Go/no‐go ERPs were submitted to temporal principal components analysis, where the P2, N2, P3, and slow wave components of interest were extracted. The performance measure of reaction time (RT) variability was positively correlated with no‐go and go errors, and also with go P2 amplitude, linking these to stimulus discrimination efforts involved in appropriate response selection. An N2c‐P3b pairing was enhanced for shorter mean RTs, supporting their involvement in the decision to execute a response. A stepwise regression model identified EC midline delta as a predictor of P3b positivity, highlighting the relevance of delta in the neural mechanisms of attentional processes. These findings clarify the electrophysiology underlying decision‐making processes in executive function, and provide a platform for further research assessing performance outcomes in larger samples and in developmental/clinical contexts. 相似文献
79.
Genevieve Z. Steiner Robert J. BarryCraig J. Gonsalvez 《International journal of psychophysiology》2013
It has been suggested that the P300 component of the ERP is an electrophysiological index of memory-updating processes associated with task-relevant stimuli. Component magnitude varies with the time separating target stimuli (target-to-target interval: TTI), with longer TTIs eliciting larger P300 amplitudes. According to the template-update perspective, TTI effects observable in the P300 reflect the updating of stimulus-templates in working memory (WM). The current study explored whether young adults' memory-task ability could predict TTI effects in P300. EEG activity was recorded from 50 university students (aged 18–25 years) while they completed an auditory equiprobable Go/NoGo task with manipulations of TTIs. Participants also completed a CogState® battery and were sorted according to their WM score. ERPs were analysed using a temporal PCA. Two P300 components, P3b and the Slow Wave, were found to linearly increase in amplitude to longer TTIs. This TTI effect differed between groups only for the P3b component: The high WM group showed a steeper increase in P3b amplitude with TTI than the low WM group. These results suggest that TTI effects in P300 are directly related to WM processes. 相似文献
80.
E. Ying Chun Lucette Belair Genevieve Jolivet Hélène Jammes 《Growth factors (Chur, Switzerland)》2013,31(1):55-66
We have investigated the localization and regulation of growth hormone (GH) receptor-related proteins in the ovine mammary gland. Using a new rabbit polyclonal antibody (7122A) directed against the recombinant extracellular domain of GH receptor (GHR-ECD) for western blot assays, we found two bands with apparent molecular weights of 70,000 and 50–60,000?Da in ovine mammary gland solubilized proteins. The 70,000-protein was consistent with a membrane GH receptor form deprived of post-translational modifications such as phosphorylation, glycosylation or ubiquitin binding. The 50–60,000?Da was consistent with soluble GH binding protein, generated by the cleavage of membrane GH receptor. The intensity of related GHR proteins increased slightly throughout mammary gland development and was correlated with the amount of GHR immunoreactivity observed in the mammary gland sections. Moreover, a temporal and spatial regulation of GHR immunoreactivity was found in alveolar epithelial cells. Clearly, marked GHR immunoreactivity was associated with the apical membranes of alveolar epithelial cells at lactation. The up-regulation of related GHR proteins during the differentiation of mammary tissue supports the hypothesis that GH may act specifically via its own receptors. In ovine mammary cells, GH was able to promote a time-dependent activation of MAP kinases such as prolactin (Prl) and placental lactogen (PL). GH was also able to promote slight and transient Stat5 DNA-binding activity. Differences in the time dependence of Stat5 DNA-binding activation by the three different ligands, GH, Prl and PL, were found. All these results emphasize the direct action of GH on ovine mammary cells and highlight the specificity of action of this ligand. 相似文献