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991.
Clinical and Experimental Medicine - Cirrhotic patients with chronic hepatitis C should be monitored for the evaluation of liver function and screening of hepatocellular carcinoma even after...  相似文献   
992.
IntroductionThe molecular mechanisms underlying alcoholic liver fibrosis and cirrhosis are not completely understood. Hepatic fibrosis involves the interplay of diverse cells and factors, including hepatic stellate cells (HSCs), Kupffer, NK cells, and T-lymphocyte subsets. Killer-cell immunoglobulin-like receptors (KIR) are membrane receptors involved in mediation between NK and activated HSCs, regulating NK cell function through their interaction with HLA-I molecules. The aim of this study was to analyse the genetic association between KIR genes and the susceptibility to or protection from alcoholic cirrhosis (AC) in a cohort of male AC patients undergoing liver transplantation (LT) with and without concomitant viral infections.Material and methodsKIR genotyping was performed in nuclear DNA extracted from 281 AC patients and compared with 319 male controls.ResultsSignificant differences between total AC patients and healthy controls were only found in the case of KIR2DL2 and KIR2DS5. KIR2DL2 was significantly underrepresented in non-viral AC patients (52.6% vs. 63.3%; p = 0.015), while patients heterozygous for KIR2DL2 were also underrepresented in the non-viral AC group compared with controls (p = 0.034). KIR2DS5 was overrepresented in this group compared with healthy controls (p = 0.002). All these observations were only evident in AC patients older than 54 years old.ConclusionsOur data suggest a contrary effect of KIR2DL2 and KIR2DS5 in AC patients older than 54 years, in whom the presence of KIR2DL2 appears to be protective against AC, whereas the presence of KIR2DS5 seems to promote the fibrotic process, particularly in patients with no associated viral infection.  相似文献   
993.
994.
Natural use of language involves at least two individuals. Some studies have focused on the interaction between senders in communicative situations and how the knowledge about the speaker can bias language comprehension. However, the mere effect of a face as a social context on language processing remains unknown. In the present study, we used event-related potentials to investigate the semantic and morphosyntactic processing of speech in the presence of a photographic portrait of the speaker. In Experiment 1, we show that the N400, a component related to semantic comprehension, increased its amplitude when processed within this minimal social context compared to a scrambled face control condition. Hence, the semantic neural processing of speech is sensitive to the concomitant perception of a picture of the speaker’s face, even if irrelevant to the content of the sentences. Moreover, a late posterior negativity effect was found to the presentation of the speaker’s face compared to control stimuli. In contrast, in Experiment 2, we found that morphosyntactic processing, as reflected in left anterior negativity and P600 effects, is not notably affected by the presence of the speaker’s portrait. Overall, the present findings suggest that the mere presence of the speaker’s image seems to trigger a minimal communicative context, increasing processing resources for language comprehension at the semantic level.  相似文献   
995.

Advancements in novel neurotechnologies, such as brain computer interfaces (BCI) and neuromodulatory devices such as deep brain stimulators (DBS), will have profound implications for society and human rights. While these technologies are improving the diagnosis and treatment of mental and neurological diseases, they can also alter individual agency and estrange those using neurotechnologies from their sense of self, challenging basic notions of what it means to be human. As an international coalition of interdisciplinary scholars and practitioners, we examine these challenges and make recommendations to mitigate negative consequences that could arise from the unregulated development or application of novel neurotechnologies. We explore potential ethical challenges in four key areas: identity and agency, privacy, bias, and enhancement. To address them, we propose (1) democratic and inclusive summits to establish globally-coordinated ethical and societal guidelines for neurotechnology development and application, (2) new measures, including “Neurorights,” for data privacy, security, and consent to empower neurotechnology users’ control over their data, (3) new methods of identifying and preventing bias, and (4) the adoption of public guidelines for safe and equitable distribution of neurotechnological devices.

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996.
Background: Facing the coronavirus disease 2019 (COVID-19) challenge on a global level, dental care professionals are encouraged to optimize universal precautions and adopt measures that ensure protection against infection by contaminated aerosols and droplets. Although aerosol transmission is possible, direct contact through large droplets is probably responsible for the vast majority of transmissions. Methods: This paper is the second of a series of 3 on the management of COVID-19 in clinical dental care settings and aims to describe the selection and use of personal protection equipment (PPE) by dental care professionals (DCP), with consideration of the level of risk associated with the planned procedures. PPE selection depends directly on the local epidemiological setting, the patient's characteristics, and the level of risk of the planned procedures. The procedures performed in the office environment are classified as low-, moderate-, or high-risk. Moderate risk includes 2 further sublevels associated with the cleaning, disinfection, and sterilization of materials for clinical procedures that do not generate aerosols. The training of DCP on how to properly don (put on) and doff (remove) PPE is as important as choosing the appropriate PPE because it can be associated with a risk of infection. Discussion: When there is limited availability of PPE, measures should be adjusted to the risk associated with the intervention. Assuming that an effective COVID-19 vaccine will be developed, once it becomes widely available for DCP, PPE requirements will likely be different. Conclusion: The proper use of PPE, together with the adoption of other operational procedures, can provide effective protection against microorganisms being transmitted via body fluids or in the air.  相似文献   
997.
998.
IntroductionThis study investigated the effects of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) on serum inflammatory mediators of rats with pulp exposure–induced apical periodontitis.MethodsForty male Wistar rats were divided into the following groups: control, untreated rats (C); control rats treated with ω-3 PUFAs (C-O); rats with pulp exposure–induced apical periodontitis (AP); and rats with pulp exposure–induced apical periodontitis treated with ω-3 PUFAs (AP-O). ω-3 PUFAs were administered orally once a day for 15 days before pulp exposure and continued for 30 days after pulp exposure. The rats were sacrificed, and then blood and jaw samples were collected. Blood analysis was conducted to determine the total number of leukocytes including neutrophils, monocytes, and lymphocytes. Proinflammatory cytokines tumor necrosis factor alpha, interleukin (IL) 6, and IL-17 were quantified by enzyme-linked immunosorbent assay. Histologic analysis was performed to confirm the development of apical periodontitis. The data were statistically evaluated using analysis of variance and the Tukey posttest. The significance level was set at 5%.ResultsThe development of apical periodontitis was confirmed in all infected groups. Bone destruction was larger in the AP group compared with the AP-O group (P < .05). Blood analysis showed that the AP and AP-O groups showed higher numbers of lymphocytes, leukocytes, monocytes, eosinophils, and expressions of tumor necrosis factor alpha and IL-6 compared with the C and C-O groups (P < .05). In contrast, the presence of leukocytes, lymphocytes, and the expression of IL-6 decreased in the AP-O group compared with the AP group (P < .05).Conclusionsω-3 PUFA supplementation influences the systemic effects caused by apical periodontitis, decreasing the number of leukocytes, lymphocytes, and IL-6 in rat blood.  相似文献   
999.
This article shows the follow-up of several cases of maxillary sinusitis of dental (usually endodontic) origin, with different manifestations, diagnostic challenges, and outcomes.Cases from 14 patients from 3 countries and treated by 7 different endodontists are presented, all of them with inflammatory sinus changes represented by mucositis, osteoperiostitis, and/or partial/full obstruction. All cases showed dental and/or sinus signs/symptoms that resolved after dental management. In 13 cases, the sinus condition had an endodontic origin, 4 of them concurrently with periodontal involvement. In 1 case, sinusitis was caused by trauma to the face. All cases but 1 had a satisfactory response of the periradicular tissues and maxillary sinus to treatment that consisted of root canal therapy, root amputation, extraction, or trauma management.The successful management of most cases reported in this article emphasizes the importance of endodontics as a specialty engaged in saving teeth and promoting health not only in the oral cavity but also in other areas that may be affected by infections of endodontic origin, including the maxillary sinus.  相似文献   
1000.
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