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排序方式: 共有3219条查询结果,搜索用时 15 毫秒
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22.
Nikolaos Athanasiou Katerina Baou Eleni Papandreou Georgia Varsou Anastasia Amfilochiou Elisavet Kontou Athanasia Pataka Konstantinos Porpodis Ioanna Tsiouprou Evangelos Kaimakamis Serafeim-Chrysovalantis Kotoulas Evgenia Katsibourlia Christina Alexopoulou Izolde Bouloukaki Meropi Panagiotarakou Aspasia Dermitzaki Nikolaos Charokopos Kyriakh Pagdatoglou Kallirroi Lamprou Sofia Pouriki Foteini Chatzivasiloglou Zoi Nouvaki Alexandra Tsirogianni Ioannis Kalomenidis Paraskevi Katsaounou Emmanouil Vagiakis 《Journal of sleep research》2023,32(1):e13656
Growing evidence suggests that sleep could affect the immunological response after vaccination. The aim of this prospective study was to investigate possible associations between regular sleep disruption and immunity response after vaccination against coronavirus disease 2019 (COVID-19). In total, 592 healthcare workers, with no previous history of COVID-19, from eight major Greek hospitals were enrolled in this study. All subjects underwent two Pfizer–BioNTech messenger ribonucleic acid (mRNA) COVID-19 vaccine BNT162b2 inoculations with an interval of 21 days between the doses. Furthermore, a questionnaire was completed 2 days after each vaccination and clinical characteristics, demographics, sleep duration, and habits were recorded. Blood samples were collected and anti-spike immunoglobulin G antibodies were measured at 20 ± 1 days after the first dose and 21 ± 2 days after the second dose. A total of 544 subjects (30% males), with median (interquartile range [IQR]) age of 46 (38–54) years and body mass index of 24·84 (22.6–28.51) kg/m2 were eligible for the study. The median (IQR) habitual duration of sleep was 6 (6–7) h/night. In all, 283 participants (52%) had a short daytime nap. In 214 (39.3%) participants the Pittsburgh Sleep Quality Index score was >5, with a higher percentage in women (74·3%, p < 0.05). Antibody levels were associated with age (r = −0.178, p < 0.001), poor sleep quality (r = −0.094, p < 0.05), insomnia (r = −0.098, p < 0.05), and nap frequency per week (r = −0.098, p < 0.05), but after adjusting for confounders, only insomnia, gender, and age were independent determinants of antibody levels. It is important to emphasise that insomnia is associated with lower antibody levels against COVID-19 after vaccination. 相似文献
23.
Certain parental cognitions about child sleep and bedtime behaviours used with their child have been linked to poorer child sleep. However, previous research has focused on mothers and explored only a limited range of sleep-related cognitions and practices. The present study investigated whether parental cognitions and sleep-related practices (both in connection with their own sleep and their child's sleep), alongside the bedtime behaviours used with their child were associated with and/or were predictive of their child's sleep. Mothers and fathers from 44 families (with a child aged 12–24 months) separately completed questionnaires reporting (i) their cognitions (about their own sleep and their child's sleep), (ii) sleep-related practices (used in connection with their own and their child's sleep) and (iii) bedtime behaviours used with their child. Child sleep was assessed through parental report and actigraphy. Both parents’ cognitions about their own sleep predicted cognitions about their child's sleep. Mothers’ own sleep-related practices predicted the types of practices they used with their child. Different patterns of maternal and paternal variables influenced parental perceptions of their child having a sleep problem. The present findings highlight the importance of including mothers and fathers in child sleep research. Parents’ dysfunctional cognitions (their own sleep) and broader sleep-related practices (their own and child sleep) should be considered when exploring influences on child sleep. Results have possible implications for targets of interventions for child sleep problems and also potential implications for theoretical models of child sleep. 相似文献
24.
Judith I. Garrison Michael E. Berens Joan Rankin Shapiro Sherri Treasurywala Georgia Floyd-Smith 《Journal of neuro-oncology》1996,30(3):213-223
Summary The growth inhibitory effect of IFN- was evaluated in 5 human glioma cell lines (AO2V4, GJC, GJR, NN and NNR) and in normal astrocyte cultures (SC and TM). All 5 glioma cell lines showed an anti-proliferative response to IFN- whereas normal glial cells were non-responsive. IFN- at 10, 100 and 500 U/ml lead to a 30%,70% and 80% relative decrease in cell number after 12 days, respectively in AO2V4 cells. GJC and GJR cell lines also responded significantly to the lowest concentration of IFN- tested and at 500 U/ml the relative cell number decreased 55%. The NN and NNR cells were the least responsive to IFN- with maximum growth inhibition of 30% at 500 U IFN-/ml. Following treatment with IFN-, AO2V4, GJC, GJR and normal astrocytes all expressed mRNA encoding the anti-viral protein, 2-5A synthetase demonstrating that IFN- bound to receptors on all four cell lines and activated signal transduction pathways required for induction of an anti-viral protein. A determination of the relative number of viable cells showed that none of these cells exhibited a significant decrease in cell viability. Since the antiproliferative response to IFN- was not primarily due to cell death, the effect of IFN- on cell cycle progression was evaluated by flow cytometry. All treated glioma cell lines showed a relative increase in proportion of cells in S phase. AO2V4 cells had a 50%–80% increase in the percentage of cells in S phase, whereas GJC, GJR and NNR had percentage increases of 20%–40%. IFN- treatment of normal astrocytes did not significantly alter their cell cycle profile. These data suggest that IFN- exerts its antiproliferative effect on glioma cells by arresting the ordered progression through S phase or decreasing entry into G2/M phase of the cell cycle. 相似文献
25.
Unusual Hepatic Tumor with Features of Mesenchymal Hamartoma and Congenital Solitary Nonparasitic Cyst 总被引:2,自引:0,他引:2
We report a hepatic tumor in an adolescent that does not fit into any of the described categories of liver tumors. The patient presented with hepatomegaly, abdominal pain, and normal liver function test; the tumor was cystic in imaging studies. The resected specimen, result of a partial hepatectomy, measured 21 cm and was multicystic with solid areas. Microscopically, the cysts were lined by a mucous-producing or intestinal-type epithelium, associated with smooth muscle and small mucous-producing glands. The solid component contained fibrous and adipose tissue, smooth muscle and thick-walled vessels. Aneuploidy was demonstrated by flow cytometry. We interpreted the tumor as having features of a mesenchymal hamartoma and congenital solitary nonparasitic cyst. It is conceivable that the lesions originated with small peribiliary glands with dilatation and intestinal metaplasia. 相似文献
26.
Panas M Karadima G Kalfakis N Psarrou O Floroskoufi P Kladi A Petersen MB Vassilopoulos D 《Journal of neurology》2000,247(12):940-942
The mechanisms underlying motor neuron degeneration in amyotrophic lateral sclerosis are not fully understood. Recent studies
suggest that apoptosis is involved in the abnormal neural death that occurs in this devastating disease. Presenilin-1, a transmembrane
protein, seems to be implicated in apoptosis. To determine whether presenilin-1 intron 8 polymorphism has an influence in
the course of amyotrophic lateral sclerosis, we examined this polymorphism genotypes in a large group of patients (n=72) with amyotrophic lateral sclerosis and in a random sample of 213 healthy individuals. The results showed a significant
difference in genotype (P < 0.04) and allele (P < 0.03) distribution between patients and controls. These results suggest a possible intervention of presenilin-1 in the
pathogenesis of amyotrophic lateral sclerosis.
Received: 14 February 2000 / Received in revised form: 20 April 2000 / Accepted: 4 June 2000 相似文献
27.
Downregulation of human kallikrein 10 (KLK10/NES1) by CpG island hypermethylation in breast, ovarian and prostate cancers. 总被引:7,自引:0,他引:7
Michael Sidiropoulos Georgios Pampalakis Georgia Sotiropoulou Dionyssios Katsaros Eleftherios P Diamandis 《Tumour biology》2005,26(6):324-336
OBJECTIVE: The human kallikrein 10 (KLK10)/normal epithelial cell-specific-1 (NES1) gene is highly expressed in normal mammary, ovary and prostate cells, but its expression is dramatically decreased in cancer cell lines. Recently, it has been shown that CpG island hypermethylation of the KLK10 gene is responsible for the tumor-specific loss of KLK10 gene expression in certain breast cancer cell lines. METHOD: We examined the role of CpG island hypermethylation in the tumor-specific loss of KLK10 expression in breast, ovarian and prostate cancers. We treated cells with the demethylating agent 5-aza-2'-deoxycytidine (dC) and monitored changes in KLK10 mRNA by RT-PCR and secreted hK10 protein expression by ELISA. The following cell lines were used: MDA-MB-231, MDA-MB-468, MCF-7, ZR-75-1, T-47D and BT-474 (breast); BG-1, MDAH-2774, HTB-75, HTB-161, PA-1 and ES-2 (ovary), and LNCaP and PC-3 (prostate). RESULTS: Upregulation of KLK10 mRNA levels, which was accompanied by an increase in secreted hK10 protein concentration, was observed for a subset of breast, ovarian, and prostate tumor cell lines after 5-aza-2'-dC. Genomic sequencing of sodium-bisulfite-treated DNA demonstrated that CpG sites within the KLK10 gene exon 3 were highly methylated. Hypermethylation of exon 3 CpG regions was also detected in primary ovarian cancers. CONCLUSION: These data suggest that CpG island hypermethylation plays an important role in the downregulation of kallikrein 10 mRNA and protein expression, but it cannot explain the pattern of expression of this gene in all cell lines or tissue tested. 相似文献
28.
Aggeliki Poulou Evgenia Grivakou Georgia Vrioni Vassiliki Koumaki Theodoros Pittaras Spyros Pournaras Athanassios Tsakris 《Journal of clinical microbiology》2014,52(5):1483-1489
The worldwide dissemination of Enterobacteriaceae producing AmpC β-lactamases and carbapenemases makes difficult the phenotypic detection of extended-spectrum β-lactamases (ESBLs), as they may be masked by these additional enzymes. A modification of the CLSI ESBL confirmatory test was developed and evaluated in a comparative study for its ability to successfully detect ESBLs among Enterobacteriaceae producing various carbapenemases (Klebsiella pneumoniae carbapenemase [KPC], VIM, NDM, and OXA-48) and plasmidic or derepressed AmpCs. The modified CLSI ESBL confirmatory test was performed with cefotaxime and ceftazidime disks with and without clavulanate, on which both boronic acid (BA) and EDTA were dispensed. A total of 162 genotypically confirmed ESBL-positive Enterobacteriaceae isolates (83 carbapenemase/ESBL producers, 25 AmpC/ESBL producers, and 54 ESBL-only producers) were examined. For comparison, 139 genotypically confirmed ESBL-negative Enterobacteriaceae isolates (94 of them possessed carbapenemases and 20 possessed AmpCs) were also tested. The standard CLSI ESBL confirmatory test was positive for 106 of the 162 ESBL producers (sensitivity, 65.4%) and showed false-positive results for 4 of the 139 non-ESBL producers (specificity, 97.1%). The modified CLSI ESBL confirmatory test detected 158 of 162 ESBL producers (sensitivity, 97.5%) and showed no false-positive results for non-ESBL producers (specificity, 100%). The findings of the study demonstrate that the modified CLSI ESBL confirmatory test using antibiotic disks containing both BA and EDTA accurately detects ESBLs in Enterobacteriaceae regardless of the coexistence of additional β-lactam resistance mechanisms. 相似文献
29.
30.
Concomitant MDS with isolated 5q deletion and MGUS: case report and review of molecular aspects 下载免费PDF全文
Florian Nolte Maximilian Mossner Johann‐Christoph Jann Daniel Nowak Tobias Boch Nadine Zoe Müller Wolf‐Karsten Hofmann Georgia Metzgeroth 《European journal of haematology》2017,98(3):302-310
Patients with monoclonal gammopathy of undetermined significance (MGUS) have a higher risk for the development of concomitant primary cancers such as multiple myeloma (MM) and myelodysplastic syndrome (MDS). We report the case of patient initially suffering from MGUS of the IgG lambda subtype for more than 10 yr, which evolved to MM and MDS with deletion (5q) with severe pancytopenia. Due to pancytopenia, he received dose‐reduced treatment with lenalidomide and dexamethasone. He achieved an ongoing transfusion independency after about 1 month of treatment. Bone marrow taken 14 months after start of treatment showed a complete cytogenetic response of the del(5q) clone and a plasma cell infiltration below 5%. In contrast to the development of MM in MGUS patients, the subsequent occurrence of MDS after diagnosis of MGUS is infrequent. Moreover, the biological association of MDS with MGUS is not sufficiently understood, but the non‐treatment‐related occurrence supports the pathogenetic role of pre‐existing alterations of stem cells. Here, we summarize data on concomitant MDS and MGUS/MM with particular emphasis on molecular aspects. 相似文献