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141.
142.
T Stokke H Holte L Smedshammer EB Smeland O Kaalhus HB Steen 《Canadian Metallurgical Quarterly》1998,77(11):1832-1838
We have examined apoptosis and proliferation in lymph node cell suspensions from patients with B-cell non-Hodgkin's lymphoma using flow cytometry. A method was developed which allowed estimation of the fractions of apoptotic cells and cells in the S-phase of the cell cycle simultaneously with tumour-characteristic light chain expression. Analysis of the tumour S-phase fraction and the tumour apoptotic fraction in lymph node cell suspensions from 95 B-cell non-Hodgkin's lymphoma (NHL) patients revealed a non-normal distribution for both parameters. The median fraction of apoptotic tumour cells was 1.1% (25 percentiles 0.5%, 2.7%). In the same samples, the median fraction of apoptotic normal cells was higher than for the tumour cells (1.9%; 25 percentiles 0.7%, 4.0%; P = 0.03). The median fraction of tumour cells in S-phase was 1.4% (25 percentiles 0.8%, 4.8%), the median fraction of normal cells in S-phase was significantly lower than for the tumour cells (1.0%; 25 percentiles 0.6%, 1.9%; P = 0.004). When the number of cases was plotted against the logarithm of the S-phase fraction of the tumour cells, a distribution with two Gaussian peaks was needed to fit the data. One peak was centred around an S-phase fraction of 0.9%; the other was centred around 7%. These peaks were separated by a valley at approximately 3%, indicating that the S-phase fraction in NHL can be classified as 'low' (< 3%) or 'high' (> 3%), independent of the median S-phase fraction. The apoptotic fractions were log-normally distributed. The median apoptotic fraction was higher (1.5%) in the 'high' S-phase group than in the 'low' S-phase group (0.8%; P = 0.02). However, there was no significant correlation between the two parameters (P > 0.05). 相似文献
143.
MG Beconi-Barker RD Roof L Millerioux FM Kausche TH Vidmar EB Smith JK Callahan VL Hubbard GA Smith TJ Gilbertson 《Canadian Metallurgical Quarterly》1995,673(2):231-244
2- and 4-Nitrophenyl beta-D-xylopyranosides (4 and 5) were transformed, via dibutyltin oxidemediated acylation, into the corresponding 2,3-di-O-benzoyl derivatives 11 and 15. Xylobiose and xylotriose were easily isolated by charcoal column chromatography from a commercially available material and converted into the di- and trisaccharide methyl 1-thio-beta-glycosides 36 and 37. The 2-and 4-nitrophenyl beta-glycosides of the beta-(1-->4)-D-xylo-oligosaccharides of dp 2-4 were synthesized by N-iodosuccinimide-silver triflate-promoted condensation using 11 and 15 as the glycosyl acceptors and ethyl 1-thio-beta-D-xylopyranoside triacetate 16, 36, and 37 as the glycosyl donors. Also described are an improved preparation of 4 and 5, and the synthesis of 1-naphthyl beta-D-xylopyranoside, as well as an alternative approach to the 2- and 4-nitrophenyl beta-xylobiosides. 相似文献
144.
RD Boggs WD McCumbee SL Cobbs DG Todd EB Kahle NL Stewart M Bailey VE Reichenbecher 《Canadian Metallurgical Quarterly》1998,6(5):361-367
OBJECTIVES: The objectives of this study were to determine whether there are differences in the electrophoretic profiles of plasma proteins from lean and obese rats and to identify a protein that was found to be more abundant in the plasma of obese rats. RESEARCH METHODS AND PROCEDURES: Plasma proteins from lean and obese Zucker fa and LA/N fa(f) rats were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The identity of a band that was differentially expressed was determined by amino acid sequencing and Western blot analysis. RESULTS: A band migrating approximately the same distance as the 116 kDa molecular weight marker was more prominent in plasma from obese rats than in plasma of lean rats. Partial sequencing of the peptide revealed that 17 of the first 18 amino acids at the amino terminus were identical with the corresponding residues in the alpha-chain of complement component C3. Western blot analysis confirmed the identity of the peptide as complement component C3. Complement C3 activity was measured using a hemolytic assay to determine whether there was a corresponding increase in the biological activity of this component in the serum of obese rats. Serum from obese rats was found to have 1.8 times as much complement component C3 activity as serum from lean rats. DISCUSSION: Elevated levels of complement C3 in genetically obese rats may be relevant because increased amounts of C3 could serve as a reservoir from which increased amounts of acylation stimulating protein, a cleavage product of complement C3, could be produced. 相似文献
145.
146.
Yu. I. Didik G. S. Korzunin V. E. Loskutov Yu. L. Gobov A. N. Sokolova I. I. Toropova 《Russian Journal of Nondestructive Testing》2007,43(9):576-583
Some general features of metrological supplementation for techniques and means of nondestructive testing of materials and articles are discussed. In particular, the CO MAГEOC calibration block for magnetic properties of a pipeline with local inhomogeneities that was developed and certified at CПEKTP, in cooperation with the Ural Research Institute of Metrology (ФГУП УНИИМ), is considered. 相似文献
147.
148.
Participants from the DSM-IV field trial for OCD (N = 381) were divided into two groups based on the SCID interview: those who met current criteria for obsessive-compulsive disorder (OCD) but not generalized anxiety disorder (GAD) and those who met current diagnostic criteria for both. The groups were compared on their severity of obsessive and compulsive symptoms, as well as on the percent of individuals who reported excessive worry concerning everyday issues (e.g. health, finances). The comorbidity rate was 20%. While the presence of GAD did not elevate OCD symptoms per se, it was associated with more pathological responsibility and indecisiveness. Excessive worries were significantly more common in those with comorbid OCD and GAD. The relationship between obsessions and worries is discussed. 相似文献
149.
The purpose of this study was to determine whether short-term tolerance develops to GABA-agonist-induced changes in saccadic eye movements (SEMs), and whether the time course for GABA-agonist induced onset and offset of impairment is similar for SEMs and for psychomotor function. An additional goal was to determine whether there are differences in sensitivity between SEMs and psychomotor function. Six healthy volunteers participated in this balanced double-blind, three-way crossover, single-dose study of placebo and two different dosage forms of the GABA-agonist alprazolam: a rapidly absorbed oral 1.5-mg compressed tablet (CT) and a 3.0-mg sustained release (SR) tablet. Treatments were separated by a 7-day washout period. Peak concentrations did not differ between CT and SR treatments, although area under the concentration-time curve (AUC) of alprazolam was greater after administration of SR than after CT, because plateau concentrations were attained after SR. Both SEM and psychomotor tests showed time-dependent responses consistent with the development of tolerance. SEMs discriminated the differences in rate of drug input of the CT and SR formulations, with impairment evident at low concentrations during absorption. SEM impairment also persisted longer than did psychomotor impairment. Peak saccade velocity is a more sensitive indicator of pharmacologic effects mediated by the GABA-benzodiazepine receptor complex than are psychomotor responses. This is probably the result of the very high GABA dependency of SEMs, along with their limited sensitivity to motivation. 相似文献
150.
Nonabsorbable barriers are considered the material by which all other barriers are judged. They have a well-established record of safety and efficacy. They are not a panacea, however. Practitioners must take special care when selecting both patients and surgical sites for GTR. Extensive experience, superior surgical ability, and meticulous attention to detail are also required if one is to achieve predictably favorable results. 相似文献