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排序方式: 共有793条查询结果,搜索用时 125 毫秒
1.
ABSTRACTThe average amount of sleep people of all ages get has declined sharply in the past 50 years. The detrimental health effects of sleep deprivation are well documented and substantial. Even though electronic media use often takes place in the hours before sleep, the extent to which media use may interact with sleep is understudied and not well understood. Communication scholars are well positioned to contribute to this area, as a systematic, theoretical understanding of the relationship between media and sleep is still lacking. This primer charts the state of knowledge on electronic media and sleep and explores possible next steps. First, we introduce the problem of sleep deprivation and describe the basic science of sleep with relevant terminology. Then, we review the research on electronic media and sleep and offer an agenda for research. 相似文献
2.
J.G. Liese C. Schoen M. van der Linden L. Lehmann D. Goettler S. Keller A. Maier F. Segerer M.A. Rose A. Streng 《Clinical microbiology and infection》2019,21(7):857-864
ObjectivesParapneumonic pleural effusions/empyema (PPE/PE) are severe complications of community-acquired pneumonia. We investigated the bacterial aetiology and incidence of paediatric PPE/PE in Germany after the introduction of universal pneumococcal conjugate vaccine (PCV) immunization for infants.MethodsChildren <18 years of age hospitalized with pneumonia-associated PPE/PE necessitating pleural drainage or persisting >7 days were reported to the German Surveillance Unit for Rare Diseases in Childhood between October 2010 and June 2017. All bacteria detected in blood or pleural fluid (by culture/PCR) were included, with serotyping for Streptococcus pneumoniae.ResultsThe median age of all 1447 PPE/PE patients was 5 years (interquartile range 3–10). In 488 of the 1447 children with PPE/PE (34%), 541 bacteria (>40 species) were detected. Aerobic gram-positive cocci accounted for 469 of 541 bacteria detected (87%); these were most frequently Streptococcus pneumoniae (41%), Streptococcus pyogenes (19%) and Staphylococcus aureus (6%). Serotype 3 accounted for 45% of 78 serotyped S. pneumoniae strains. Annual PPE/PE incidence varied between 14 (95%CI 12–16) and 18 (95%CI 16–21) PPE/PE per million children. Incidence of S. pneumoniae PPE/PE decreased from 3.5 (95%CI 2.5–4.6) per million children in 2010/11 to 1.5 (95%CI 0.9–2.4) in 2013/14 (p 0.002), followed by a re-increase to 2.2 (95%CI 1.5–3.2) by 2016/17 (p 0.205).ConclusionsIn the era of widespread PCV immunization, cases of paediatric PPE/PE were still caused mainly by S. pneumoniae and, increasingly, by S. pyogenes. The re-increase in the incidence of PPE/PE overall and in S. pneumoniae-associated PPE/PE indicates ongoing changes in the bacterial aetiology and requires further surveillance. 相似文献
3.
Rothner AD 《Headache》2003,43(4):427-428
Curr Pain Headache Rep. 2002;6:233-239.
This article reviews the less frequently encountered varieties of migraine. It is suggested that these disorders be approached by evaluating possible underlying etiologies before positively diagnosing migraine. This decreases the likelihood of "missing" structural or metabolic disorders. The classification, diagnostic evaluation, differential diagnosis, and treatment options of these disorders is reviewed and a selection of references appended for additional information.
Comment: Dr. Rothner is one of the most prominent pediatric neurology headache specialists in the country, and he sees a variety of atypical presentations of migraine. This is an excellent review of such presentations. SJT 相似文献
This article reviews the less frequently encountered varieties of migraine. It is suggested that these disorders be approached by evaluating possible underlying etiologies before positively diagnosing migraine. This decreases the likelihood of "missing" structural or metabolic disorders. The classification, diagnostic evaluation, differential diagnosis, and treatment options of these disorders is reviewed and a selection of references appended for additional information.
Comment: Dr. Rothner is one of the most prominent pediatric neurology headache specialists in the country, and he sees a variety of atypical presentations of migraine. This is an excellent review of such presentations. SJT 相似文献
4.
Scott S. Short Liese C.C. Pruitt Michael D. Rollins 《Journal of pediatric surgery》2018,53(7):1437-1439
Total colonic aganglionosis is a rare phenotype of Hirschsprung disease (HD). While the diagnosis is generally established within the neonatal period there are reports of delayed presentation. In this case, we describe a 9-month old girl with no previous medical or surgical history who presented with a small bowel obstruction. A contrast enema performed as part of the work up demonstrated right sided colonic diverticula with no other anatomical abnormalities. Surgical intervention was required to manage the obstruction and colonic biopsies were consistent with HD. This case highlights the association of the unusual finding of colonic diverticula with total colonic HD in infants. 相似文献
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IJ Webb ; CE Eickhoff ; AD Elias ; LJ Ayash ; CA Wheeler ; GN Schwartz ; GD Demetri ; KC Anderson 《Transfusion》1996,36(2):160-167
BACKGROUND: Peripheral blood progenitor cells (PBPCs) are commonly collected and used to reconstitute hematopoiesis after high-dose chemotherapy. However, strategies for optimal collection and assessment of leukapheresis components are not standardized. STUDY DESIGN and METHODS: Hematopoietic progenitor cell assays were performed on 369 leukapheresis components collected from 95 patients who had received doxorubicin-based chemotherapy and/or granulocyte-colony-stimulating factor (G-CSF). Precollection patient hematologic values, leukapheresis collection values, component hematopoietic progenitor cell assays, and patient outcome measures were summarized. The kinetics of mononuclear cell (MNC) and PBPC mobilization were assessed among four patient groups. RESULTS: Patient group was a significant predictor of the peripheral blood MNC count on the day of collection (p<0.0001), and that value was a significant predictor of granulocyte-macrophage– colony-forming unit (CFU-GM) yield (p<0.0001). This relationship between the peripheral blood MNC count on the day of collection and CFU- GM yield differed according to patient group (p<0.0001). CFU-GM made up a larger fraction of peripheral blood MNCs collected from patients who received chemotherapy plus G-CSF than collected from those who received G-CSF alone. Moreover, the peripheral blood MNC count and the corresponding CFU-GM yield increased significantly on consecutive days of collection in patient groups receiving chemotherapy and G-CSF but were unchanged or decreased in patients receiving G-CSF alone. CONCLUSION: The relationship between peripheral blood MNC count and leukapheresis component CFU-GM yield differed significantly between patients who received chemotherapy and G-CSF and those who received G- CSF alone for the mobilization of PBPCs. Patient peripheral blood MNC count and component CFU-GM yield are useful for both assessing and suggesting revisions to PBPC mobilization and collection strategies. 相似文献
9.
Prenatal identification of potential donors for umbilical cord blood transplantation for Fanconi anemia 总被引:1,自引:0,他引:1
AD Auerbach ; Q Liu ; R Ghosh ; MS Pollack ; GW Douglas ; HE Broxmeyer 《Transfusion》1990,30(8):682-687
Reported here are studies of Fanconi anemia fetal cells that led to the first use of umbilical cord blood for hematopoietic reconstitution in a clinical trial. Prenatal diagnosis and HLA typing were performed in fetuses at risk for Fanconi anemia (FA) to identify, prior to birth, those that were unaffected with the syndrome and were HLA-identical to affected siblings. Umbilical cord blood was harvested at the delivery of these infants; assays of progenitor cells indicated the presence of colony-forming units-granulocyte-macrophage (CFU-GM) in numbers similar to those of bone marrow CFU-GM that are associated with successful engraftment in HLA-matched allogeneic bone marrow transplantation. The possibility that umbilical cord blood from a single individual can be used as an alternative to bone marrow for hematopoietic reconstitution has now been demonstrated by the successful engraftment of two patients with FA. Progenitor cell assays of umbilical cord blood collected at the birth of a child affected with FA, who had been misdiagnosed on the basis of chorionic villus sampling (CVS) studies, indicated a profound deficiency in colony formation, consistent with previously reported abnormalities in the growth of FA cells in vitro. These results suggest that the hematopoietic disorder in FA is related to an underlying problem with cell proliferation. 相似文献
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