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101.
Effect of corrections for blood glucose and body size on [18F]FDG PET standardised uptake values in lung cancer 总被引:4,自引:0,他引:4
Hallett WA Marsden PK Cronin BF O'Doherty MJ 《European journal of nuclear medicine》2001,28(7):919-922
Standardised uptake values (SUVs) are commonly used as a semi-quantitative index of 2-[18F]fluoro-2-deoxy-D-glucose (FDG) tracer uptake in positron emission tomography (PET). Studies have shown that SUVs may depend on body size and blood glucose concentration and corrections for these effects have been proposed in the literature. This retrospective study investigated the effect of the proposed corrections on SUVs from a group of 154 patients with lung cancer who had scans on a dedicated PET scanner. A total of 252 SUVs were requested as an aid to staging during consideration for surgical resection. SUVs were calculated normalised to body weight (SUVw), lean body mass (SUV(LBM)) and body surface area (SUV(BSA)). The following correlations were examined: SUV with height, weight and body surface area for the different body size normalisations; SUVw and SUVw x blood glucose (SUV(BG)) with blood glucose; SUVw with scan time post injection; and SUVw with apparent lesion diameter. Significant correlations were only observed between: SUV(LBM) and height (P=0.007); SUVw and scan time (P=0.007); SUVw and lesion diameter (P=0.0005); and SUV(BG) and blood glucose (P<0.00001). The correlation between SUV(LBM) and height suggests that lean body mass as a function of height alone should not be used to normalise SUVs; however, the lean body mass calculated from a height and weight nomogram did not show this effect. The strong correlation between SUV(BG) and blood glucose concentration suggests that for non-diabetic fasted patients, lung tumour SUVs should not be adjusted for blood glucose. 相似文献
102.
103.
Human myeloid alpha 3-fucosyltransferase is involved in the expression of the sialyl-Lewis(x) determinant, a ligand for E- and P-selectin 总被引:1,自引:0,他引:1
Easton EW; Schiphorst WE; van Drunen E; van der Schoot CE; van den Eijnden DH 《Blood》1993,81(11):2978-2986
The sialyl-Lex determinant (NeuAc alpha 2-->3Gal beta 1-->4[Fuc alpha- 1-->3]GlcNAc) has been identified as a major ligand in the selectin- mediated adhesion of neutrophils and monocytes to activated endothelium or platelets. This carbohydrate epitope is formed by the sequential action of alpha 3-sialyltransferase and alpha 3-fucosyltransferase on N- acetyllactosamine (Gal beta 1-->4GlcNAc) disaccharide termini of glycoconjugates. We have addressed the role of the human myeloid alpha 3-fucosyltransferase in the expression of this epitope at the leucocyte surface by determining its activity in human-mouse leukemic cell hybrids (WEGLI), normal human granulocytes and chronic myeloid leukemia (CML) cells using sialylated and desialylated glycoproteins and oligosaccharides as acceptor substrates. In contrast to what has been reported for the myeloid-type enzyme, we found that the alpha 3- fucosyltransferase of the cells studied can use sialylated acceptors be it that the activity is several times lower than with asialo- substrates. Characterization of the product obtained with a sialylated oligosaccharide indicated that the enzyme can catalyze the formation of the sialyl-Le(x) structure. Flow cytometry of the WEGLI cells using a sialyl-Le(x)-specific monoclonal antibody (MoAb) showed that these cells indeed express sialyl-Lex at their surface, provided that they contain human chromosome 11. Earlier the presence of this chromosome had been correlated with the expression of alpha 3-fucosyltransferase activity. In addition to sialyl-Le(x), WEGLI cells containing chromosome 11 showed high-expression levels of related structures recognized by antibodies VIM-2 and VIM-8, suggesting that fucose addition can occur at both distal and proximal GlcNAc residues in poly- N-acetyl-lactosaminoglycan sequences. Based on the human chromosome contents it could be ruled out that the alpha 3-fucosyltransferase of WEGLI cells is a Lewis-type alpha 3/4- or plasma-type alpha 3- fucosyltransferase, the genes of which have been mapped to chromosome 19. It is concluded that the enzyme studied is of the myeloid-type and indeed is involved in the synthesis of sialyl-Le(x) (and also VIM-2 and VIM-8 structures) in leukocytes provided that its expression is at a sufficiently high level. 相似文献
104.
Alvaro Pascual Eric M. Wassermann Norihiro Sadato Mark Hallett 《Annals of neurology》1995,38(6):910-915
We studied the cortical motor output maps of the first dorsal interosseous (FDI) of both hands and the abductor digitiminimi of the reading hand in 6 blind proficient Braille readers. The maps were generated using transcranial magnetic stimulation. We compared the maps obtained on a day in which they worked as Braille proofreaders (reading Braille for approximately 6 hours) with the maps obtained on a day they took off from work. On the work day, the maps for the FDI of the reading hand were significantly larger after the working shift than in the morning after having been off work for 2 days. These changes were not seen for the same muscle on the day off work or on any of the 2 days in the other two muscles studied. These results illustrate the rapid modulation in motor cortical outputs in relation to preceding activity and emphasize the importance of precise timing in studies of the neurophysiological correlates of skill acquisition. 相似文献
105.
P V Tishler B Woodward J O'Connor D A Holbrook L J Seidman M Hallett D J Knighton 《The American journal of psychiatry》1985,142(12):1430-1436
The authors screened 3,867 psychiatric inpatients for intermittent acute porphyria by use of a spot test to detect diminished activity of the erythrocyte enzyme porphobilinogen (PBG) deaminase. Eighteen individuals so identified also had persistently diminished quantitative activity of PBG deaminase. Eight of these appeared to have intermittent acute porphyria by the added criteria of increased urinary delta-aminolevulinic acid or PBG or a family history of intermittent acute porphyria. The overall prevalence of intermittent acute porphyria was 0.21%, a considerably higher rate than that in the general population. Most of the subjects with the disorder had periods of agitated psychosis and apathetic or depressed withdrawal, with signs of neuropsychological impairment. Neurologic abnormalities were not prevalent. 相似文献
106.
107.
108.
Intervention against smoking and its relationship to general practitioners' smoking habits 总被引:1,自引:1,他引:0
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R. Hallett 《The British journal of general practice》1983,33(254):565-567
A postal survey was carried out in June and July 1980 to find out if there was any relationship between smoking habits of general practitioners and their reported intervention against smoking among their patients. Responses from 342 general practitioners in London and Kent indicated that there was a relationship: general practitioners who smoked cigarettes (13 per cent of the sample) were less likely to advise or help their patients to stop smoking than general practitioners who smoked a pipe or cigars or who did not smoke at all. The survey also yielded an estimate of smoking prevalence among general practitioners which indicated that prevalence has continued to decline, and that fewer general practitioners are being recruited to smoking. 相似文献
109.
110.
Virginia M. Sanders Anne N. Tucker Kimber L. White Bernadine M. Kauffmann Patricia Hallett Richard A. Carchman Joseph F. Borzelleca Albert E. Munson 《Toxicology and applied pharmacology》1982,62(3):358-368
A 14-day study using male CD-1 mice exposed to trichloroethylene (TCE) by daily po gavage suggested inhibition of cell-mediated immunity. Therefore, an evaluation of the immune status was undertaken after exposure of male and female mice to TCE in the drinking water for either 4 or 6 months. The immunological parameters assessed were humoral immunity, cell-mediated immunity, lymphocyte responsiveness, bone marrow function, and macrophage function. Females were more affected than males by TCE, particularly after a 4-month exposure. In the female, humoral immunity was inhibited only at the highest concentrations of TCE (2.5 and 5 mg/ml), whereas cell-mediated immunity and bone marrow stem cell colonization were inhibited at all four concentrations of TCE (0.1, 1.0, 2,5, and 5 mg/ml). The males were relatively unaffected after both 4 and 6 months compared to effects observed in the 14-day study. 相似文献