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The aim of this safety study in mice was to determine in vivo toxicity and biodistribution potential of a single and multiple doses of L-glutamic acid-g-p(HEMA) polymeric nanoparticles as a drug delivery system. The single dose did not cause any lethal effect, and its acute oral LD50 was >2.000 mg/kg body weight (bw). Multiple doses (25, 50, or 100 mg/kg bw) given over 28 days resulted in no significant differences in body and relative organ weights compared to control. These results are supported by biochemical and histological findings. Moreover, nanoparticle exposure did not result in statistically significant differences in micronucleus counts in bone marrow cells compared to control. Nanoparticle distribution was time-dependent, and they reached the organs and even bone marrow by hour 6, as established by ex vivo imaging with the IVIS® spectrum imaging system. In conclusion, L-glutamic acid-g-p(HEMA) polymeric nanoparticles appear biocompatible and have a potential use as a drug delivery system.KEY WORDS: biocompatibility, blood biochemistry, genotoxicity, histology, in vivo toxicity, micronucleus test, polymers  相似文献   
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Journal of Public Health - Media as a source of information can shape public opinion regarding the COVID-19 response. Identifying how and where people seek information during the COVID-19 outbreak...  相似文献   
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Clinical Oral Investigations - The objective of this systematic review and meta-analysis (SRM) was to answer the question whether the use of ultrasonic irrigation (UI) results in less postoperative...  相似文献   
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Background and aimsDeterioration of anthropometric and lung function parameters was shown to precede the onset of cystic fibrosis-related diabetes (CFRD) in adults. In children, studies have been conducted in small cohorts with relatively short observation period. Study objectives were to document the longitudinal trends of anthropometric, pulmonary, nutritional and metabolic parameters from cystic fibrosis (CF) diagnosis to the ascertainment of abnormal glucose tolerance and identify parameters associated with the incidence of such abnormalities in a pediatric CF cohort.Methods and resultsRetrospective cohort study of 281 children with CF. Longitudinal trends of anthropometric, lung function, nutritional and metabolic data were generated from CF diagnosis to the ascertainment of abnormal glucose tolerance defined as the presence of either impaired glucose tolerance (IGT), unconfirmed CFRD or CFRD. Cox models and Kaplan–Meier curves were used to identify factors associated with developing abnormal glucose tolerance.Forty-five percent of cohort had normal glucose tolerance (NGT), 27% IGT, 10% unconfirmed CFRD and 18% CFRD. Children who developed CFRD displayed lower height z-scores from a very early age. Conversely, HbA1c levels began to rise closer to CFRD ascertainment. Height z-scores (HR: 0.45; CI 95% [0.29–0.69]) and HbA1c (HR: 2.43; CI 95% [1.86–3.18]) in years preceding ascertainment were associated with the risk of developing CFRD.ConclusionChildren who developed CFRD display distinctive trends for height z-scores from a very early age, whereas HbA1c appears as a marker of established glucose metabolism derangements.  相似文献   
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According to global neuronal workspace (GNW) theory, conscious access relies on long-distance cerebral connectivity to allow a global neuronal ignition coding for conscious content. In patients with schizophrenia and bipolar disorder, both alterations in cerebral connectivity and an increased threshold for conscious perception have been reported. The implications of abnormal structural connectivity for disrupted conscious access and the relationship between these two deficits and psychopathology remain unclear. The aim of this study was to determine the extent to which structural connectivity is correlated with consciousness threshold, particularly in psychosis. We used a visual masking paradigm to measure consciousness threshold, and diffusion MRI tractography to assess structural connectivity in 97 humans of either sex with varying degrees of psychosis: healthy control subjects (n = 46), schizophrenia patients (n = 25), and bipolar disorder patients with (n = 17) and without (n = 9) a history of psychosis. Patients with psychosis (schizophrenia and bipolar disorder with psychotic features) had an elevated masking threshold compared with control subjects and bipolar disorder patients without psychotic features. Masking threshold correlated negatively with the mean general fractional anisotropy of white matter tracts exclusively within the GNW network (inferior frontal-occipital fasciculus, cingulum, and corpus callosum). Mediation analysis demonstrated that alterations in long-distance connectivity were associated with an increased masking threshold, which in turn was linked to psychotic symptoms. Our findings support the hypothesis that long-distance structural connectivity within the GNW plays a crucial role in conscious access, and that conscious access may mediate the association between impaired structural connectivity and psychosis.  相似文献   
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There have been a number of investigations of the efficacy and safety of etanercept. This study was performed to obtain long-term drug survival data (ie, time to drug discontinuation) for etanercept, and the reasons for its discontinuation. The study population consisted of patients with psoriatic arthritis and psoriasis followed up by our clinic, registered in the Turkish Psoriasis Registry (PSR-TR) and treated with etanercept for at least 4 weeks between January 1, 2005, and January 31, 2020. The efficacy of etanercept was evaluated in terms of the Psoriasis Area and Severity Index (PASI) 75, PASI 90 and PASI 100 response rates at 12, 24, 36, and 48 weeks, and annually thereafter. The behaviors of the patients with respect to the use of etanercept, and the outcomes of those who continued to use it during the COVID-19 pandemic, were also investigated.  相似文献   
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