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排序方式: 共有1181条查询结果,搜索用时 15 毫秒
41.
42.
Simone CS Wolfkamp Caroline Verseyden Esther WM Vogels Sander Meisner Kirsten Boonstra Charlotte P Peters Pieter CF Stokkers Anje A te Velde 《World journal of gastroenterology : WJG》2014,20(10):2664-2672
AIM:To investigate if the presence of relevant genetic polymorphisms has effect on the effectual clearance of bacteria by monocytes and granulocytes in patients with Crohn’s disease(CD).METHODS:In this study,we assessed the differential responses in phagocytosis by measuring the phagocytic activity and the percentage of active phagocytic monocytes and granulocytes in inflammatory bowel disease patients as well as healthy controls.As both autophagy related like 1(ATG16L1)and immunityrelated guanosine triphosphatase gene are autophagy genes associated with CD and more recently nucleo-tide-binding ligomerization domain-containing protein2(NOD2)has been identified as a potent inducer of autophagy we genotyped the patients for these variants and correlated this to the phagocytic reaction.The genotyping was done with restriction fragment length polymorphisms analysis and the phagocytosis was determined with the pHrodo?Escherichia coli Bioparticles Phagocytosis kit for flowcytometry.RESULTS:In this study,we demonstrate that analysis of the monocyte and granulocyte populations of patients with CD and ulcerative colitis showed a comparable phagocytic activity(ratio of mean fluorescence intensity)between the patient groups and the healthy controls.CD patients show a significantly higher phagocytic capacity(ratio mean percentage of phagocytic cells)compared to healthy controls(51.91%±2.85%vs 37.67%±7.06%,P=0.05).The extend of disease was not of influence.However,variants of ATG16L1(WT:2.03±0.19 vs homozygoot variant:4.38±0.37,P<0.009)as well as NOD2(C-ins)(heterozygous variant:42.08±2.94 vs homozygous variant:75.58±4.34(P=0.05)are associated with the phagocytic activity in patients with CD.CONCLUSION:Monocytes of CD patients show enhanced phagocytosis associated with the presence of ATG16L1 and NOD2 variants.This could be part of the pathophysiological mechanism resulting in the disease. 相似文献
43.
Jay R Shapiro Caressa Lietman Monica Grover James T Lu Sandesh CS Nagamani Brian C Dawson Dustin M Baldridge Matthew N Bainbridge Dan H Cohn Maria Blazo Timothy T Roberts Feng‐Shu Brennen Yimei Wu Richard A Gibbs Pamela Melvin Philippe M Campeau Brendan H Lee 《Journal of bone and mineral research》2013,28(7):1523-1530
44.
Ultrastructural characteristics of human mesenchymal stromal (stem) cells derived from bone marrow and term placenta 总被引:6,自引:0,他引:6
Pasquinelli G Tazzari P Ricci F Vaselli C Buzzi M Conte R Orrico C Foroni L Stella A Alviano F Bagnara GP Lucarelli E 《Ultrastructural pathology》2007,31(1):23-31
Human mesenchymal stromal (stem) cells (hMSCs) isolated from adult bone marrow (BM-hMSCs) as well as amnion (AM-hMSCs) and chorion (CM-hMSCs) term placenta leaves were studied by transmission electron microscopy (TEM) to investigate their ultrastructural basic phenotype. At flow cytometry, the isolated cells showed a homogeneous expression of markers commonly used to identify hMSCs, i.e., CD105, CD44, CD90, CD166, HLA-ABC positivities, and CD45, AC133, and HLA-DR negativities. However, TEM revealed subtle yet significant differences. BM-hMSCs had mesenchymal features with dilated cisternae of rough endoplasmic reticulum (rER) and peripheral collections of multiloculated clear blisters; this latter finding mostly representing complex foldings of the plasma membrane could be revelatory of the in situ cell arrangement in the niche microenvironment. Unlike BM-hMSCs, CM-hMSCs were more primitive and metabolically quiescent, their major features being the presence of rER stacks and large peripheral collections of unbound glycogen. AM-hMSCs showed a hybrid epithelial-mesenchymal ultrastructural phenotype; epithelial characters included non-intestinal-type surface microvilli, intracytoplasmic lumina lined with microvilli, and intercellular junctions; mesenchymal features included rER profiles, lipid droplets, and well-developed foci of contractile filaments with dense bodies. These features are consistent with the view that AM-hMSCs have a pluripotent potential. In conclusion, this study documents that ultrastructural differences exist among phenotypically similar hMSCs derived from human bone marrow and term placenta leaves; such differences could be revelatory of the hMSCs in vitro differentiation potential and may provide useful clues to attempt their in situ identification. 相似文献
45.
46.
Provision of childhood primary care services and differences between types of providers (family practice physicians, pediatricians, nurse practitioners, and physicians' assistants) were explored in this study. A mail survey was conducted in Wyoming using a questionnaire based on the recommendations from the U. S. Preventive Service Task Force. Sixty-one percent of the providers returned questionnaires. While some areas of assessment, screening, and treatment/counseling services were provided at high levels, many were not. Gaps exist particularly in the areas of behavioral and lifestyle assessment and treatment/counseling. Only small differences existed between types of providers. However, nurse practitioners and pediatricians were more likely to report that they followed recommendations, while physicians' assistants were least likely to report that they followed recommendations. 相似文献
47.
48.
Genee Brukwitzki MSN RN Cynthia Holmgren MSN RN OCN Regina Marie Maibusch MS RN CS 《International journal of nursing terminologies and classifications》1996,7(2):63-69
The investigators designed this validation study to determine the defining characteristics of the nursing diagnosis ineffective airway clearance. Using Fehring's Diagnostic Content Validity Model, 546 nurses who care for respiratory clients validated one major and 19 minor defining characteristics. Nine characteristics previously described in the literature were eliminated. Clarification of the defining characteristics of this diagnosis improves communication in practice, education and research. 相似文献
49.
Linda Funk Barloon MS RN CS Psychiatric Clinical Nurse Specialist 《Journal of child and adolescent psychiatric nursing》1997,10(4):43-44
Performance Breakthroughs for Adolescents With Learning Disabilities or ADD. G. Markel & J. Greenbaum. 相似文献
50.
Characterization of the effects of cultured vascular cells on the activation of blood coagulation 总被引:9,自引:0,他引:9
The coagulant properties of intact bovine vascular cells (aortic endothelial and smooth muscle cells) and human vascular cells (cutaneous and foreskin microvascular cells, umbilical venous endothelium) grown in vitro were studied. Compared to nonvascular cells (fibroblasts, corneal endothelial cells, fetal lung or intestinal mucosal cells), vascular cells had little procoagulant activity. Radioimmunologic measurement of thrombin in recalcified plasma demonstrated markedly lower concentrations of thrombin in the presence of vascular endothelial and smooth muscle cells compared to corneal endothelial and fetal lung cells. The low thrombin concentrations were not a consequence of thrombin binding to the vascular cells nor were they due to accelerated thrombin inactivation by antithrombin-III or alpha 2-macroglobulin. Neither vascular cells nor the nonvascular cells promoted contact activation of plasma as measured by a sensitive specific assay for kallikrein. Studies with intact cell monolayers and purified factors VIIa and X indicated that while nonvascular cells express tissue factor activity, vascular cells do not exhibit this property. These data suggest that the nonthrombogenic nature of intact vascular cells is due to their failure to initiate contact activation and to express tissue factor activity. In addition, the primary difference in coagulant potential between vascular cells and nonvascular cells is the lack of tissue factor expression by the vascular cells. 相似文献