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排序方式: 共有1018条查询结果,搜索用时 15 毫秒
1.
Monolayer cultures of normal human bone cells contain multiple subpopulations of alkaline phosphatase positive cells 总被引:5,自引:0,他引:5
Toshikatsu Matsuyama K. -H. William Lau Jon E. Wergedal 《Calcified tissue international》1990,47(5):276-283
Summary Cytochemical staining of normal human bone cells in monolayer cultures for alkaline phosphatase (ALP) indicated that the cultures
contained mixed-cell populations. Time course evaluations of the cytochemical staining revealed, in addition to the ALP-negative
cell population, at least two subpopulations of ALP-positive human bone cells with different levels of ALP. A cytochemical
method has been developed which separates the ALP-positive cells into high and intermediate ALP subpopulations. In this method,
human bone cells were stained for ALP using an azo-dye method and incubating at 4°C for 10 and 30 minutes, respectively. We
defined the cell population that stained positively for ALP at 10 minutes as strong ALP-positive cells, and both strong and
intermediate cells were stained at 30 minutes. The intermediate cells were determined from the difference between the values
at the two time points. The intra- and interassay variations of the assay, with the same investigator in blinded investigations,
were both less than 10% and the interobserver variation was approximately 25%. Analysis of the distribution of ALP levels
in cells with a laser densitometer confirmed the presence of at least three cell subpopulations. 1,25(OH)2D3 treatment increased the proportions of both ALP-positive cell populations, whereas TGF-beta treatment increased only the
intermediate ALP-positive cell population. On the contrary, fluoride increased the proportion of the strong ALP cells, and
IGF-1 had no effect on the proportions of either ALP-positive subpopulation. When the ALP-specific activity was compared with
the percentage of each ALP-positive subpopulations for the cells treated with effectors, the ALP-specific activity correlated
with the total ALP-positive and with the strong ALP-positive populations but not with the intermediate ALP-positive subpopulation.
In summary, this study represents the first evidence that normal human bone cells in monolayer cultures contained at least
two subpopulations of ALP-positive cells, and that bone cell effectors could have differential effects on each cell population. 相似文献
2.
Preliminary evidence for a role of apolipoprotein E alleles in identifying haemodialysis patients at high vascular risk 总被引:1,自引:0,他引:1
Olmer M; Renucci JE; Planells R; Bouchouareb D; Purgus R 《Nephrology, dialysis, transplantation》1997,12(4):691-693
Conventional risk factors have very low predictive power in identifying
haemodialysis patients at high risk of vascular accidents. A role for
apolipoprotein E isotypes was looked for in a small, but rigorously
defined, cohort of longterm haemodialysis patients. In individuals with
high vascular risk, as identified by higher common carotid intima/media
thickness, we found an excess of apolipoprotein E4 alleles. This
preliminary result requires confirmation in large patient cohorts.
相似文献
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Hodgkin disease: CT of the thymus 总被引:2,自引:0,他引:2
The computed tomography (CT) scans in two groups of patients with Hodgkin disease were reviewed to determine the frequency of thymic enlargement. In 50 CT scans from 50 patients with evidence of thoracic disease on CT scans who were examined for primary staging, the thymus was enlarged in 15 of 50 (30%). Fifty CT scans were obtained from 44 patients at the time of 50 separate episodes of known or suspected relapse. Relapse occurred in the mediastinum in 12 episodes, lung parenchyma in five, and both sites in one. Thymic enlargement thought to be due to involvement by disease was present in seven of 18 (38%). Mediastinal disease was associated with thymic enlargement in all but one patient in whom a thymic cyst developed after radiation therapy. Differentiation of thymic enlargement from enlarged superior mediastinal lymph nodes was easily made in all but two patients. Thymic enlargement in the absence of lymph node enlargement may indicate a different disease, since isolated Hodgkin disease of the thymus is uncommon. Primary thymic tumor should be considered initially, whereas after treatment, rebound hyperplasia of the thymus may be the cause of enlargement. 相似文献
6.
Solitary bronchioloalveolar carcinoma: CT criteria 总被引:14,自引:0,他引:14
Kuhlman JE; Fishman EK; Kuhajda FP; Meziane MM; Khouri NF; Zerhouni EA; Siegelman SS 《Radiology》1988,167(2):379-382
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis. 相似文献
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A randomized controlled trial of electromagnetic therapy in the primary care management of venous leg ulceration 总被引:1,自引:1,他引:0
OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care. 相似文献
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