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K T Smith S L Wagner M J Bottema 《Proceedings of the National Academy of Sciences of the United States of America》1984,81(16):5237-5241
This article describes a method for clarifying and sharpening radiographs. The method uses convolution with a computed tomography reconstruction kernel and a noise elimination procedure to control the noise amplification of the convolution. The effect is to flatten global variations and to sharpen and magnify local variations. Examples from industry and medicine are included. 相似文献
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BACKGROUND: Chronic Obstructive Pulmonary Disease (COPD) forms an increasing health problem. Despite smoking cessation improving the prognosis of the disease, many patients persist smoking. The present study presents the results of a smoking cessation counseling protocol in general practice (Smoking Cessation in patients with COPD in general practice (SMOCC)). METHODS: A randomized controlled trial of patients with COPD compared smoking cessation counseling according to an intensified minimal intervention strategy with usual care. In total 43 general practices with 392 patients participated in Nijmegen, The Netherlands, in 2001-2002. RESULTS: Significantly more smokers in the experimental group made a quit attempt (44.9% versus 36.5%) and actually quit smoking than in the control group (16.0% versus 8.8%). The motivation to stop smoking at baseline was not associated with smoking cessation. CONCLUSION: The SMOCC strategy doubled the self-reported quit rates and was complied well by the general practitioners. Implementation in general practice is recommended. 相似文献
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Coulthard MG Lickliter JD Subanesan N Chen K Webb GC Lowry AJ Koblar S Bottema CD Boyd AW 《Growth factors (Chur, Switzerland)》2001,18(4):303-317
The Eph family of receptor tyrosine kinases plays a crucial role during development and is implicated in oncogenesis. Using a partial cDNA clone of an Eph-related kinase (Esk) we isolated the complete coding region of a gene which we show to be murine EphA1 by both structural and functional criteria. The chromosomal localization is shown to be syntenic to hEphA1 and the genomic organization also shows distinct features found in the hEphA1 gene. Functionally, in keeping with findings for the human homologue, both soluble recombinant and "native" mEphA1 show preferential binding to ephrin A1. However, we also observed significant binding to other A-type ligands as has been observed for other Eph receptors. We analysed the expression of mEphA1 mRNA by in situ hybridization on tissue sections. mEphA1 was expressed in epithelial elements of skin, adult thymus, kidney and adrenal cortex. Taken together with previous Northern blotting data these results suggest that mEphA1 is expressed widely in differentiated epithelial cells. 相似文献
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LINDA STRAND ANDREW JENKINS NILS GRUDE ANNE‐GRY ALLUM HILDE‐CHRISTINE MYKLAND FOUROUGH L. NOWROUZIAN BJøRN‐ERIK KRISTIANSEN 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2010,118(8):571-577
Strand L, Jenkins A, Grude N, Allum A‐G, Mykland H‐C, Nowrouzian FL, Kristiansen B‐E. Emergence of fluoroquinolone‐resistant clonal group A: clonal analysis of Norwegian and Russian E. coli isolates. APMIS 2010; 118: 571–77. We describe a study of urinary tract and intestinal isolates of Escherichia coli from Norway and Russia using automated ribotyping, single nucleotide polymorphism analysis for clonal group A (CgA) supplemented with phylogrouping, virulence gene profiling and resistance profiling. CgA comprised 19% of the Norwegian UTI isolates from 2001. Two highly multiresistant fluoroquinolone‐resistant CgA isolates were found. Ribotypes clustered into four major and six minor groups (ribogroups). Fluoroquinolone‐resistant isolates and phylogroups A and B1 were associated with ribogroup RA. Ribogroup RB predominated among Russian UTI isolates and was predominantly phylogroup A and depleted in P‐fimbriae. Ribogroup RC predominated among Norwegian UTI isolates and was rich in virulence factors (S‐fimbriae, haemagglutinin and haemolysin) and predominantly phylogroup B2 and D. Ribogroup RG was associated with CgA and predominantly phylogroup D. Ribogroups RD, RE and RF had too few members for statistical analysis. The correlation between ribotype and phylogenetic group was not as strong as reported in other studies. 相似文献
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George Groeneweg Frank JPM Huygen Sjoerd P Niehof Feikje Wesseldijk Johannes BJ Bussmann Fabienne C Schasfoort Dirk L Stronks Freek J Zijlstra 《BMC musculoskeletal disorders》2008,9(1):143
Background
This double-blind, randomized, controlled trial investigated the effect of the phosphodiesterase-5 inhibitor tadalafil on the microcirculation in patients with cold Complex Regional Pain Syndrome (CRPS) in one lower extremity. 相似文献49.
Magnetic resonance (MR) imaging was performed on 14 patients with histologically proved osteosarcoma (mean age, 14.4 years). There was excellent correlation of intramedullary tumor extent as determined with MR imaging and pathologic examination (r = 99%). This was facilitated by the presence of a chemical shift artifact at the tumor-marrow interface on the T1-weighted images. The correlation between CT and pathologic findings was not as good (r = 84%). In a single patient, however, a 10-cm length of sclerotic bone was incorrectly interpreted as being tumor. If this case is excluded, the correlation between CT and pathologic findings improves significantly (r = 96%). T2-weighted images were optimal in demonstrating soft-tissue bulk and breach of the epiphysis or cortex. Vascular involvement was also readily defined. The T2 value of the tumor soft-tissue component decreased in patients who were deemed to have responded well to therapy. Two patients with very high T2 values after chemotherapy developed wide-spread metastatic disease and died. Phosphorus-31 MR spectroscopy of five patients with osteosarcoma showed elevated levels of phosphomonoesters (PMEs), inorganic phosphate (Pi), and phosphodiesters (PDEs). PME and PDE peak areas decreased in three patients after chemotherapy, while Pi peak areas increased. 相似文献
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