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51.
Accuracy of eosinophils and eosinophil cationic protein to predict steroid improvement in asthma 总被引:1,自引:0,他引:1
R. J. Meijer D. S. Postma H. F. Kauffman L. R. Arends G. H. Koëter H. A. M. Kerstjens 《Clinical and experimental allergy》2002,32(7):1096-1103
BACKGROUND: There is a large variability in clinical response to corticosteroid treatment in patients with asthma. Several markers of inflammation like eosinophils and eosinophil cationic protein (ECP), as well as exhaled nitric oxide (NO), are good candidates to predict clinical response. AIM: We wanted to determine whether we could actually predict a favourable response to inhaled corticosteroids in individual patients. METHODS: One hundred and twenty patients with unstable asthma were treated with either prednisolone 30 mg/day, fluticasone propionate 1000 microg/day b.i.d. or fluticasone propionate 250 microg/day b.i.d., both via Diskhaler. They were treated during 2 weeks, in a double-blind, parallel group, double dummy design. We measured eosinophils and ECP in blood and sputum, and exhaled nitric oxide as inflammatory parameters before and after 2 weeks in order to predict the changes in forced expiratory volume in 1 s (FEV1), provocative concentration of methacholine causing a 20% fall in FEV1 (PC20 Mch), and asthma quality of life (QOL). Secondly, to test whether these results were applicable in clinical practice we determined the individual prediction of corticosteroid response. RESULTS: We found that changes in FEV1, PC20 Mch and QOL with corticosteroids were predominantly predicted by their respective baseline value and to a smaller extent by eosinophils in blood or sputum. ECP, measured in blood or sputum, was certainly not better than eosinophils in predicting clinical response to corticosteroids. Smoking status was an additional predictor for change in FEV1, but not for change in PC20 Mch or QOL. Prediction of a good clinical response was poor. For instance, high sputum eosinophils (> or = 3%) correctly predicted an improvement in PC20 Mch in only 65% of the patients. CONCLUSION: Our findings show that baseline values of the clinical parameters used as outcome parameters are the major predictors of clinical response to corticosteroids. Eosinophil percentage in blood or sputum adds to this, whereas ECP provides no additional information. Correct prediction of clinical response in an individual patient, however, remains poor with our currently used clinical and inflammatory parameters. 相似文献
52.
C. Fellbaum J. Sträter M. -L. Hansmann 《Virchows Archiv : an international journal of pathology》1993,423(5):335-341
Extranodal lymphomas of the thyroid (n=19), kidney (n=15) and testis (n=30) were investigated histologically and immunohistochemically for follicular dendritic cell pattern using the monoclonal antibody Ki-FDC1P. This recognizes follicular dendritic cells in paraffin sections. Follicular dendritic cells were most predominant in lymphomas of the thyroid. These thyroid lymphomas showed the morphological features of mucosa-associated lymphoid tissue (MALT) type lymphomas in 18 of 19 cases and were classified as high-grade malignant lymphoma of MALT type with evidence of a low-grade malignant component (n=18). Ten of these cases contained destroyed reactive follicles of follicular dendritic cells. In 6 of these 10 cases follicular dendritic cells occurred in a pattern of tumour-associated abortive follicle type. The remaining lymphoma of the thyroid was an immunoblastic lymphoma of B-cell type showing no detectable follicular dendritic cells. In extranodal lymphomas of non-MALT type follicular dendritic cells occurred in only two cases where immunocytoma involved the kidney. Malignant lymphomas of the kidney (chronic lymphocytic leukaemia,n=2; immunocytoma,n=4; centroblastic lymphoma,n=9) and of the testis (immunocytoma,n=2; centroblastic lymphoma,n=27; immunoblastic lymphoma of B-cell type,n=1) revealed no characteristics of MALT type lymphoma, cytologically or with respect to follicular dendritic cells. Classical lymphoepithelial lesions formed by centrocyte-like cells, a hallmark of MALT, occurred exclusively in thyroid lymphomas of MALT type. Although occurrence of classical lymphoepithelial lesions formed by centrocyte-like cells was limited to thyroid lymphomas of MALT type, a growth pattern of lymphoid blasts, with formation of lesions mimicking lymphoepithelial lesions superficially, was found in 6 of 27 testicular centroblastic lymphomas. Follicular dendritic cells in non-Hodgkin's lymphomas of MALT type show distinct follicular patterns not found in other extranodal lymphomas such as those found in the kidney and testis. 相似文献
53.
54.
High intensity focused ultrasound--a surgical technique for the treatment of discrete liver tumours 总被引:10,自引:0,他引:10
The treatment of discrete liver tumours is often a difficult clinical problem. High intensity, focused ultrasound may provide one form of therapy for such disease. The ability to focus ultrasound precisely on a predetermined volume allows the possibility of selective tissue destruction at this position without damage to intervening tissues. We have investigated this both in vivo and in excised liver samples in vitro. Quantitative and qualitative studies have been carried out on the relationship between the ultrasonic exposure and the lesion shape, position and volume. In addition, the highly echogenic nature of the ultrasonic lesion has been studied, in an attempt to determine whether 'real time' observation of the extent of tissue damage is feasible. 相似文献
55.
Detection of leptospiral DNA by nucleic acid hybridisation with 32P- and biotin-labelled probes 总被引:12,自引:0,他引:12
Dot hybridisation with 32P- and biotin-labelled probes prepared from leptospiral DNA was performed to develop a sensitive and specific diagnostic method for early infection with leptospires. The smallest amounts of leptospiral DNA that could be detected with 32P- and biotin-labelled probes was 1.5 pg and 5 pg, respectively, corresponding to about 750 and 2500 leptospires. Dot hybridisation with a 32P-labelled probe detected leptospiral DNA in sera from all of 14 experimentally infected golden hamsters. The smallest amount of leptospiral DNA detected in these experiments corresponded to about 2500 leptospires. In the test conditions described in this study, the sensitivity of dot hybridisation with a biotin-labelled probe was lower. Little cross-hybridisation was observed with unrelated DNAs which indicates that dot hybridisation could be a useful diagnostic method. 相似文献
56.
R. Kleta J. Hirsch S. Heindenreich H. Schlüter W. Zidek E. Schlatter 《Pflügers Archiv : European journal of physiology》1995,430(5):713-720
Diadenosine polyphosphates have been shown to influence renal perfusion pressure. As mesangial cells may contribute to these effects we investigated the effects of diadenosine triphosphate (Ap3A), diadenosine tetraphosphate (Ap4A), diadenosine pentaphosphate (Ap5A) and diadenosine hexaphosphate (Ap6A) on membrane voltage (V
m) and membrane conductance (g
m) in mesangial cells (MC) of normotensive Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats in primary and long-term culture. We applied the patch-clamp technique in the fast-whole-cell configuration to measure V
m and g
m. To compare the effects of diadenosine polyphosphates with hitherto known agonists we also tested adenosine 5-triphosphate (ATP) and angiotensin II (Ang II). As there was no significant difference in the V
m values in MC of WKY (–42±1 mV, n=70) and SHR rats (–45±2 mV, n=99) as well as in the agonist-induced changes of V
m, all data were pooled. The V
m of all the cells was –44±1 mV (n=169) and g
m was 15.9±1.8 nS (n=141). Ion-exchange experiments showed the presence of a K+ and a non-selective cation conductance in resting MC whereas a Cl– conductance or a Na+selective conductance could not be observed. Ap3A, Ap4A, Ap5A, AP6A and ATP each at a concentration of 5 mol/l, led to a significant depolarization of V
m by 5±2 mV (n=14), 7±1 mV (n=25), 3±1 mV (n=23), 2±1 mV (n=16), and 14±2 mV (n=23), respectively. For Ap4A, the most potent diadenosine polyphosphate, we determined the half-maximally effective concentration (EC
50) as 6 mol/l (n=5–25), for ATP as 2 mol/l (n=9–37), and for Ang II as 8 nmol/l (n=6–18). Ap4A 100 mol/l increased g
m significantly by 55±20% (n=16), 100 mol/l ATP by 135±60% (n=18). The diadenosine polyphosphates examined were able to depolarize V
m (Ang II >ATP> Ap4A>Ap3A>Ap5A>Ap6A) by activation of a Cl– conductance and a non-selective cation conductance, as do ATP or Ang II. 相似文献
57.
Gyrgy Bertalan Istvn Rusznk gnes Ercsnyi Pter Anna 《Macromolecular chemistry and physics.》1980,181(9):1807-1814
The polymerization of octanelactame ( 1 ) initiated by HCl takes place according to the characteristic kinetic curves. Both characteristics, i.e., the fast initial and the extremely slow further stages, and the kinetic anomaly (in certain cases under otherwise identical conditions less polymer is formed at higher than at lower temperatures) can be interpreted easily on the basis of a mechanism already suggested by the authors. The two relevant chain growth reactions, i.e., lactam addition on \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm R}\mathop {\rm N}\limits^ \oplus {\rm H}_{\rm 3} $\end{document}-groups and the reaction between \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm R}\mathop {\rm N}\limits^ \oplus {\rm H}_{\rm 3} $\end{document} and N-acylamide groups, proceed through a tetrahedral intermediate in two directions, one of them being the known chain growth, the other one an amidine (or acylamidine) formation, in which the active groups, ensuring chain growth, desactivate. Both kinetic characteristics could be interpreted on the basis of the suggested mechanism, by measuring the amounts of amino and amidine groups with the progress of polymerization. 相似文献
58.
Zrubka Zsombor Vékás Péter Németh Péter Dobos Ágota Hajdu Ottó Kovács Levente Gulácsi László Hibbard Judith Péntek Márta 《The European journal of health economics》2022,23(8):1341-1355
The European Journal of Health Economics - Patient activation comprises the skills, knowledge and motivation necessary for patients’ effective contribution to their care. We adapted and... 相似文献
59.