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排序方式: 共有720条查询结果,搜索用时 15 毫秒
71.
Hemodynamic effects on atherosclerosis and thrombosis 总被引:1,自引:0,他引:1
72.
Effect of flow on polymorphonuclear leukocyte/endothelial cell adhesion 总被引:24,自引:6,他引:24
The effect of flow on the adhesion of polymorphonuclear leukocytes (PMNL) to vascular endothelium was investigated using a parallel plate chamber with a well-defined flow field. Washed PMNL were perfused over a monolayer of primary human umbilical vein endothelial cells (HUVEC) pretreated with formyl-methionyl-leucyl-phenylalanine (FMLP, 1 X 10(-7) mol/L) for five minutes. In other experiments HUVEC were pretreated with interleukin 1 (IL1,2 U/mL) for four hours. PMNL adhesion to stimulated and control HUVEC was measured over a physiologic range of wall shear stresses. PMNL adhesion to nylon-coated surface was also studied. At a wall shear stress of 0.98 dynes/cm2,283 +/- 37.3 PMNL/mm2 (mean +/- SEM) adhered to FMLP-treated HUVEC while 195 +/- 20.3 PMNL/mm2 adhered to control HUVEC. At 1.96 dynes/cm2, 68 +/- 14.1 PMNL/mm2 adhered to FMLP-treated HUVEC and 42 +/- 6.0 PMNL/mm2 adhered to control HUVEC. At 3.92 dynes/cm2, virtually no PMNL adherence was noted on either control or FMLP-treated HUVEC. On IL 1-treated HUVEC at 1.96 dynes/cm2, 371 +/- 25.8 PMNL/mm2 adhered while 28 +/- 2.9 PMNL/mm2 adhered to control HUVEC. PMNL adhesion to IL 1-treated and control HUVEC dropped to 10.2 +/- 3.8 and 6.8 +/- 3.5 PMNL/mm2, respectively, at 3.01 dynes/cm2. The effect of flow on PMNL adhesion appears to be an important factor in determining the outcome of the PMNL/HUVEC adhesive interaction under these experimental conditions. 相似文献
73.
To explore the biochemical and physiologic basis of the overlapping effects of interleukin-1 alpha (IL-1 alpha) and tumor necrosis factor alpha (TNF-alpha) on myeloid cytokine production, we have studied the dynamics of granulocyte colony-stimulating factor (G-CSF) and granulocyte-monocyte colony-stimulating factor (GM-CSF) production as well as IL-1 receptor and TNF receptor expression in a clonally derived bone marrow stromal cell strain (CDCL). IL-1 alpha and TNF alpha act in a synergistic manner to stimulate G-CSF and GM-CSF production by CDCL, resulting in an increase in CSF secretion that is 250-fold greater than that observed with either cytokine alone. This synergism in protein secretion is paralleled by synergistic increases the steady-state level of GM- and G-CSF mRNA, with supra-additive levels achieved by 24 hours. Coincident with this synergistic induction of myeloid CSFs, treatment of CDCL cells with IL-1 alpha induces a 300% increase in the expression of TNF receptors. IL-1 alpha induction of TNF receptors reaches a peak after 6 hours and gradually returns to baseline level by 24 hours. IL-1 alpha does not affect TNF receptor ligand binding affinity. A kinetic study comparing IL-1/TNF synergistic induction of growth factor secretion with IL-1 alpha induction of TNF receptors shows that these events occur in parallel. In contrast with the induction of TNF receptors by IL-1 alpha, treatment with TNF alpha has no effect on either the number of IL-1 receptors expressed by CDCL cells or IL-1 receptor ligand binding affinity. Brief treatment of IL-1 alpha/TNF alpha-stimulated CDCL cells with cycloheximide before receptor induction reduces the synergistic increase in growth factor mRNA by 40% to 60% compared with cells not treated with CHX. Taken together, these results raise the possibility that IL-1 alpha cross-induction of TNF receptors may contribute to the biochemical mechanisms underlying the synergistic stimulation of G-CSF and GM-CSF production by IL-1 alpha and TNF alpha. 相似文献
74.
75.
P Möllborg G Wennergren SG Norvenius B Alm 《Acta paediatrica (Oslo, Norway : 1992)》2011,100(2):226-230
Aim: In spite of several reports of an increased risk of sudden infant death syndrome (SIDS) in connection with bed‐sharing, it is not an uncommon practice. The aim of this study was to examine bed‐sharing at 6 months of age and the factors that are associated with bed‐sharing. Methods: Our cohort comprised 8176 randomly chosen families. At 6 month of age, the families received an invitation to the study, with a questionnaire, which was completed by 5605 families (response rate 68.5%). Results: Of the families, 19.8% bed‐shared. In the multivariate analysis, we found a correlation between breast‐feeding and bed‐sharing (breast‐feeding at 6 months: OR 1.94; 95% CI 1.56, 2.41). Moreover, we found an association with 3+ nightly awakenings at 6 months (2.70; 2.20, 3.32). It was more common to share a bed if the parent was single (2.04; 1.19, 3.51) and less common if the infant was bottle‐fed in the first week (0.70; 0.54, 0.90). Never using a pacifier was associated with a higher frequency of bed‐sharing. Conclusion: We found a correlation between breast‐feeding and bed‐sharing as well as between sleeping problems and a single parent. A lower percentage of infants sleeping in the parental bed were seen in association with formula feeding in the first week after birth. 相似文献
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78.
CH Reynolds BBSc DP Crewther PhD SG Crewther PhD SJ West BSc 《Clinical & experimental ophthalmology》1998,26(S1):S117-S119
79.
SG Gotha 《MedR Medizinrecht》2006,24(8):497-502
Abstrakt 1. Für die Berechtigung der Krankenkasse zum Einbehalt der Anschubfinanzierung kommt es auf bereits geschlossene IV-Vertr?ge
an.
2. Apotheken geh?ren nicht zu den nach § 140b SGB V zum Vertragsabschluss berechtigten Leistungserbringern.
3. Zum Sinn und Zweck einer Integrierten Versorgung. (Leits?tze des Bearbeiters) 相似文献
80.