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Clinical Rheumatology - Prof. Ari Polachek on of the author of the published version of this article missed to add his second affiliation which is the Department of Rheumatology, Tel Aviv Sourasky...  相似文献   
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Cultured porcine thyroid cells did not reassociate into functional follicles in the presence of TSH unless the initial seeding density was adequate. At 0.2 X 10(6) cells/35 mm diameter culture dish the cells rapidly formed a monolayer even in the presence of TSH (128 microunits./ml), and radioiodide uptake was not significantly increased compared with that in control cells. Seeding densities of 1-3 X 10(6) cells/dish resulted in cultures which responded to TSH with follicular development and increased radioiodide uptake. A cell-free membrane fraction of thyroid homogenate restored the ability of cultures seeded at low densities to respond to TSH with development of follicular morphology and increased radioiodide uptake. Delaying the addition of TSH by 48 h markedly reduced the stimulation of follicular development and radioiodide uptake of cultures. Addition of membrane fractions, or an alkali-soluble fraction of membranes, at zero time improved the responses to TSH added after a 48-h delay. It was concluded that maintenance of differentiation and of TSH-responsiveness in cultured thyroid cells was influenced by cell-cell contact.  相似文献   
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Previously we have shown that expression of the insulin-like growth factor II (IGF-II) gene in 36 normal smooth muscle tissues (myometria) and 26 benign smooth muscle tumors (leiomyomas) was detectable by Northern blot analysis but that the RNA levels were low. In 9 of 20 malignant smooth muscle tumors (leiomyosarcomas) IGF-II gene expression was also low or absent, while in 11 of 20 the IGF-II gene was abundantly expressed. In 32 of these tissues we have now studied the DNA methylation state of the IGF-II gene. For the analysis of overall methylation of the gene the restriction endonucleases HpaII and MspI were used. In normal smooth muscle and in leiomyomas the IGF-II gene appeared to be methylated. In leiomyosarcomas with low IGF-II gene expression the DNA was partly demethylated. In leiomyosarcomas with abundant IGF-II gene expression overall methylation of the DNA tended to be low. In addition, we have studied the methylation state of one particular CpG site in the IGF-II gene with the restriction endonuclease AvaII. The results of the latter analysis confirm the analysis with HpaII and MspI. In conclusion, in malignant smooth muscle tumors the data indicate an inverse correlation between CpG methylation and expression of the IGF-II gene.  相似文献   
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We measured CBF and the CMRglc in normal controls and in patients with severe liver disease and evidence for minimal hepatic encephalopathy using positron emission tomography. Regions were defined in frontal, temporal, parietal, and visual cortex; the thalamus; the caudate; the cerebellum; and the white matter along with a whole-slice value obtained at the level of the thalamus. There was no difference in whole-slice CBF and CMRglc values. Individual regional values were normalized to the whole-slice value and subjected to a two-way repeated measures analysis of variance. When normalized CBF and CMRglc values for regions were compared between groups, significant differences were demonstrated (F = 5.650, p = 0.00014 and F = 4.58, p = 0.0073, respectively). These pattern differences were due to higher CBF and CMRglc in the cerebellum, thalamus, and caudate in patients and lower values in the cortex. Standardized coefficients extracted from a discriminant function analysis permitted correct group assignment for 95.5% of the CBF studies and for 92.9% of the CMRglc studies. The similarity of the altered pattern of cerebral metabolism and flow in our patients to that seen in rats subjected to portacaval shunts or ammonia infusions suggests that this toxin may alter flow and metabolism and that this, in turn, causes the clinical expression of encephalopathy.  相似文献   
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The effects of introduction of a low steroid regime and pre-transplant blood transfusion were evaluated. The kidney and patient survival rates for the period before such a policy was adopted were compared with the period after this policy. There has been a highly significant rise in patient survival rates to the present level of 95 per cent at three years. There was a similar rise in three year graft survival rates from less than 40 per cent to 66 per cent.  相似文献   
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