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101.
The use of protective facemasks (PFMs) negatively impacts respiratory and dermal mechanisms of human thermoregulation through impairment of convection, evaporation, and radiation processes. The relatively minor reported increases in core temperature directly attributable to the wearing of PFMs suggest that associated perceptions of increased body temperature may have a significant psychological component or that regional or global brain temperature changes are involved. Modifications in PFM structure, components, and materials might allow for improved heat dissipation and enhanced compliance with use. 相似文献
102.
Mark A. Perazella Steven G. Coca Mehmet Kanbay Ursula C. Brewster Chirag R. Parikh 《Clinical journal of the American Society of Nephrology》2008,3(6):1615-1619
Background and objectives: Urine microscopy is the oldest and one of the most commonly used tests for differential diagnosis of acute kidney injury (AKI), but its performance has not been adequately studied in the setting of AKI.Design, setting, participants, & measurements: Fresh urine samples were obtained from 267 consecutive patients with AKI, and urinary sediment was examined. The cause of AKI was assessed at two time points: (1) Before urine microscopy diagnosis and (2) after patient discharge or death (final diagnosis). A urinary scoring system also was created on the basis of casts and renal tubular epithelial cells (RTEC) to differentiate acute tubular necrosis (ATN) from prerenal AKI.Results: The urinary sediment scoring system was highly predictive of the final diagnosis of ATN. In patients with a high pretest probability of ATN (initial diagnosis of ATN), any casts or RTEC (score ≥2) resulted in very high positive predictive value and low negative predictive value for a final diagnosis of ATN. In patients with a low pretest probability of ATN (initial diagnosis of prerenal AKI), lack of casts or RTEC on urinary sediment examination had a sensitivity of 0.73 and specificity of 0.75 for a final diagnosis of prerenal AKI. The negative predictive value of lack of casts or RTEC in patients with low pretest probability of disease was 91%.Conclusions: Urine sediment examination is a valuable diagnostic tool for confirming the diagnosis of ATN. A score of ≥2 on an ATN urinary sediment scoring system is an extremely strong predictor of ATN.Urine microscopy is the oldest and one of the most commonly used tests for differential diagnosis of acute kidney injury (AKI). The diagnosis of AKI is currently and primarily based on measurement of serum creatinine, blood urea nitrogen, and urine output. In addition to these parameters, urine biochemistry and microscopy provide the vital information in the differentiation of AKI into traditional categories of prerenal azotemia and acute tubular necrosis (ATN) (1–5). Therapies and prognosis for prerenal AKI and ATN differ substantially; therefore, early clinical differentiation is important. Although urine microscopy with sediment examination is commonly suggested for patients with AKI in the literature, its precise diagnostic value is not clearly known. Furthermore, there has been a gradual trend away from routine urine microscopy in the clinical evaluation of AKI.Urinary microscopy in patients with ATN classically is described as containing renal tubular epithelial cells (RTEC), RTEC casts, granular casts, and muddy brown or mixed cellular casts, whereas sediment in patients with prerenal AKI usually demonstrates occasional hyaline or fine granular casts (6–10). Because urine microscopy is readily available, rapid, and inexpensive, valuable information that will improve the differential diagnosis of AKI might be quickly obtained from this test. The aims of this study were to describe the urinary sediment findings in a cohort of patients with AKI and to determine the performance of urinary sediment examination for differentiation between ATN and prerenal AKI, the most common causes of AKI in the hospital. 相似文献
103.
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
104.
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
105.
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109.
CH Reynolds BBSc DP Crewther PhD SG Crewther PhD SJ West BSc 《Clinical & experimental ophthalmology》1998,26(S1):S117-S119
110.
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