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排序方式: 共有870条查询结果,搜索用时 265 毫秒
1.
Margaret Comerford Freda 《Journal of pediatric health care》2005,19(3):151-156
INTRODUCTION: The purpose of this study was to evaluate the readability of American Academy of Pediatrics (AAP) patient education brochures. METHOD: Seventy-four brochures were analyzed using two readability formulas. RESULTS: Mean readability for all 74 brochures was grade 7.94 using the Flesch-Kincaid formula, and grade 10.1 with SMOG formula (P = .001). Using the SMOG formula, no brochures were of acceptably low (< or =8th grade) readability levels (range 8.3 to 12.7). Using the Flesch-Kincaid formula, 41 of the 74 had acceptable readability levels (< or =8th grade). The SMOG formula routinely assessed brochures 2 to 3 grade levels higher than did the Flesch-Kincaid formula. DISCUSSION: Some AAP patient education brochures have acceptably low levels of readability, but at least half are written at higher than acceptable readability levels for the general public. This study also demonstrated statistically significant variability between the two different readability formulas; had only the SMOG formula been used, all of the brochures would have had unacceptably high readability levels. Readability is an essential concept for patient education materials. Professional associations that develop and market patient education materials should test for readability and publish those readability levels on each piece of patient education so health care providers will know if the materials are appropriate for their patients. 相似文献
2.
I A Cotgreave P Moldéus R Brattsand A Hallberg C M Andersson L Engman 《Biochemical pharmacology》1992,43(4):793-802
Here we describe a new class of organoselenium compounds possessing glutathione peroxidase-like activity. The parent compound, alpha-(phenylselenenyl)acetophenone (PSAP), increased the rate of reaction of glutathione with H2O2, tert-butylhydroperoxide, cumene hydroperoxide, linoleic acid hydroperoxide and dilinoleyl lecithin hydroperoxide by 7.0, 25.1, 34.1, 19.1 and 8.4-fold, respectively, as assessed by the oxidized glutathione (GSSG) reductase enzyme assay. Direct assay of the removal of hydrogen peroxide and glutathione from reaction mixtures confirmed the peroxidase-like activities of these selenoorganic compounds, but indicate that the conventional coupled GSSG reductase assay may be unsuitable for the assessment of the catalytic capacity of PSAP and Ebselen. One possible mechanism of catalysis by PSAP involves an initial oxidation at selenium. Thiol may then react with the selenoxide to yield a selenium (II) compound, H2O and a disulfide. Compounds derived from PSAP may provide potential selenium-based anti-inflammatory agents. 相似文献
3.
P Nicotera M Rundgren D J Porubek I Cotgreave P Moldéus S Orrenius S D Nelson 《Chemical research in toxicology》1989,2(1):46-50
The cytotoxicity of acetaminophen (paracetamol) has been shown to be associated with a disruption of intracellular Ca2+ homeostasis caused by the interaction of its metabolite N-acetyl-p-benzoquinone imine (NAPQI) with hepatocyte thiols [Moore, M., et al. (1985) J. Biol. Chem. 260, 13035-13040]. Inasmuch as NAPQI can both covalently bind to thiols and oxidize thiols, we investigated the effects of two dimethylated analogues of NAPQI, one of which (2,6-dimethyl-NAPQI) primarily binds to thiols and the other of which (3,5-dimethyl-NAPQI) primarily oxidizes thiols. Of the three compounds, 2,6-dimethyl-NAPQI decreased protein thiols to the greatest extent and also inhibited hepatocyte plasma membrane Ca(2+)-ATPase to the greatest extent. The 3,5-dimethylated analogue decreased protein thiols to the least extent and inhibited the plasma membrane Ca(2+)-ATPase to a lesser extent. The cytotoxicity of all three compounds was preceded by a sustained elevation in cytosolic Ca2+ as compared to the transient rise caused by the alpha-agonist phenylephrine. Again, the 2,6-dimethyl analogue was the most potent of the three compounds. The thiol reagent dithiothreitol (DTT), which reversed the inhibition of the Ca(2+)-ATPase and the rise in cytosolic Ca2+, also protected against cytotoxicity. Agents that are known to inhibit either Ca(2+)-dependent proteases or phospholipases significantly delayed the onset of cytotoxicity caused by NAPQI and its analogues. Our results suggest that both arylation and oxidation of protein thiols may result in the elevation of cytosolic Ca2+ and in cytotoxicity and that arylation of critical thiol groups appears to be the more lethal reaction. 相似文献
4.
Margaret Comerford Freda RN EdD FAAN Mary Lou Moore RN PhD FAAN 《Journal of nursing scholarship》1995,27(1):61-64
Interdisciplinary collaboration between nursing and medicine is a valued goal, but one which is difficult to achieve. Two nurses who are faculty members in medical schools reflect on their unique roles and how these encompass interdisciplinary research, teaching, and practice. 相似文献
5.
Autoimmune hepatitis type 1 and primary biliary cirrhosis have distinct bone marrow cytokine production 总被引:3,自引:0,他引:3
Zachou K Rigopoulou EI Tsikrikoni A Alexandrakis MG Passam F Kyriakou DS Stathakis NE Dalekos GN 《Journal of autoimmunity》2005,25(4):389-288
We have recently reported differences in the hematopoiesis between autoimmune hepatitis type 1 (AIH-1) and primary biliary cirrhosis (PBC). In view of the notion that cytokines are regulators of hematopoiesis, we investigated in our tertiary center the cytokine production in the bone marrow (BM) of the same consecutive cohort of patients (13 AIH-1, 13 PBC, 10 healthy and 7 patients with cirrhosis due to chronic hepatitis B). Interferon-gamma (IFN-gamma), interleukin-4 (IL-4), interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta (TGF-beta) were determined in the supernatants of long-term BM cultures by ELISAs. IL-4, TNF-alpha and TGF-beta were found significantly increased in the BM of PBC patients compared to AIH-1 and both control groups. AIH-1 patients had significantly higher BM IL-10 compared to PBC patients and higher IL-10, IL-4 and TNF-alpha compared to controls. BM IFN-gamma was significantly higher in PBC and AIH-1 patients compared to controls. In AIH-1 patients, IL-10 was positively correlated with CD34+, CD34+/CD38- and CD34+/CD38+ cell proportions. In conclusion, the BM cytokine microenvironment of PBC and AIH-1 patients differs significantly compared to that of healthy individuals and cirrhotic patients of non-autoimmune etiology. Differences were also found between patients with PBC and AH-1. The implication of BM in the pathogenesis of autoimmune liver diseases is possible and needs further investigation. 相似文献
6.
Complement activation by apoptotic endothelial cells following hypoxia/reoxygenation 总被引:5,自引:0,他引:5
Reperfusion of ischaemic tissue initiates an inflammatory reaction that increases tissue injury. Complement activation at the endothelium contributes to this inflammation. This study investigated the mechanism of complement activation following reoxygenation of hypoxic human umbilical vein endothelial cells (HUVEC) as a model for complement activation observed on endothelium in reperfused ischaemic tissue. HUVEC cultured in 1% oxygen followed by reoxygenation activated the classical complement pathway resulting in C3 deposition. There was an increase in apoptotic cells in these cultures that was demonstrated by binding of fluorescein isothiocyanate-Annexin V and staining for hypodiploid nuclei. To determine if apoptotic HUVEC activate complement, uniformly apoptotic cells were produced by serum and growth factor deprivation. These cells, but not the control HUVEC, activated the classical complement pathway in the absence of antibody or other serum factors. To determine if apoptotic cells in the reoxygenated cultures were activating complement, fluorescent analysis was done. Annexin V binding and C3d deposition on cells from reoxygenated cultures showed complete concordance on the subpopulation of apoptotic cells. In addition, complement activation following reoxygenation of HUVEC was eliminated by treatment of the cultures with a caspase inhibitor during reoxygenation. These results suggest that oxidative damage to endothelial cells during reoxygenation initiates apoptosis with exposure of phosphatidylserine. Apoptotic cells directly activate the classical pathway of complement by binding C1. Activation of complement at the endothelium may contribute to the inflammatory response as well as clearance and repair. 相似文献
7.
DNA vaccines induce CTL attack on target tumor epitopes, but tumor elimination in vivo also requires sufficient effector CTL to enter the site, guided by inflammatory chemokines. Many herpesviruses contain genes for chemokine and chemokine receptor-like proteins to protect infected cells from immune attack. To assess if this evasion strategy could protect tumor cells, we used a model where CTL specific for a single epitope were the only effectors. Following DNA vaccination, CTL eliminated tumor cells from a subcutaneous site. However, introducing a viral gene encoding a secreted broad-spectrum chemokine-binding protein (M3) into tumor cells completely blocked CTL attack. Transduced tumor cells also protected neighboring non-transduced tumor. These findings confirm the importance of chemokines for migration of CTL to a non-lymphoid site. They may have relevance for escape of human virus-associated malignancies, and raise the question of whether analogous molecules might contribute to the failure of CTL to eliminate tumors. 相似文献
8.
9.
Dai Y Zhang S Yamamoto J Ao M Belin TR Cheung F Hifumi SS 《Community mental health journal》1999,35(6):537-542
There is a high prevalence of suicide amongelderly Chinese, and particularly among elderly Chinesewomen in Mainland China with a prevalence of 19.6 perhundred thousand. Since Chinese individuals may much more highly value education, acognitive-behavioral package originated by RicardoMunoz, Ph.D. was adapted for Chinese American subjects.The material was videotaped in eight sessions,approximately 25 minutes in length, to be shown to communitysubjects who were at least 40 years and over. Inaddition, a videotape of muscular relaxation techniqueswas made. A manual written in Chinese about the content of each class, was given to each subject whenhe/she attended. The experimental group showedsignificant improvement in the scores in the HamiltonDepression Scale, including the Somatic Subscale in the Hamilton Anxiety Scale. There was nosignificant improvement in the control group on any ofthe measures. Thus the study suggests the efficacy ofpsychoeducational classes in reducing symptoms ofdepression in non-patient community elderly. Other studiesare being conducted among Korean Americans and JapaneseAmericans in the United States, and also in the Orientamong Japanese elderly. 相似文献
10.
Regulation of complement activation by C-reactive protein. 总被引:22,自引:0,他引:22
C-reactive protein (CRP) is an acute-phase serum protein and a mediator of innate immunity. CRP binds to microbial polysaccharides and to ligands exposed on damaged cells. Binding of CRP to these substrates activates the classical complement pathway leading to their uptake by phagocytic cells. Complement activation by CRP is restricted to C1, C4, C2 and C3 with little consumption of C5-9. Surface bound CRP reduces deposition of and generation of C5b-9 by the alternative pathway and deposition of C3b and lysis by the lectin pathway. These activities of CRP are the result of recruitment of factor H resulting in regulation of C3b on bacteria or erythrocytes. Evidence is presented for direct binding of H to CRP. H binding to CRP or C3b immobilized on microtiter wells was demonstrated by ELISA. Attachment of CRP to a surface was required for H binding. H binding to CRP was not inhibited by EDTA or phosphocholine, which inhibit ligand binding, but was inhibited by a 13 amino acid CRP peptide. The peptide sequence was identical to the region of CRP that showed the best alignment to H binding peptides from Streptococcus pyogenes (M6) and Neisseria gonorrhoeae (Por1A). The results suggest that CRP bound to a surface provides secondary binding sites for H resulting in greater regulation of alternative pathway amplification and C5 convertases. Complement activation by CRP may help limit the inflammatory response by providing opsonization with minimal generation of C5a and C5b-9. 相似文献