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141.
D G Sawutz S S Singh L Tiberio E Koszewski C G Johnson C L Johnson 《Immunopharmacology》1992,24(1):1-10
In this study, we examined the effect of TNFa on bradykinin (BK) B2 receptor binding and function in human A431 epidermoid carcinoma cells. [3H]BK binds to a single class of receptors on A431 cells in a saturable and reversible manner. A binding affinity (KD) of 3.0 +/- 0.3 nM (n = 4) and a Bmax of 151 +/- 14 fmols/10(6) cells, representing approximately 90,000 BK receptors per cell, was observed. The rank order of potency for BK agonist peptides indicates that the A431 BK receptor appears to be of the B2 subtype. When A431 cells were incubated with TNFa (10 ng/ml) for 48 h prior to BK binding, a significant decrease in the number of BK receptors compared to control was observed. TNFa did not influence the affinity of BK binding to A431 cells and direct addition of TNFa to the binding assay did not effect BK binding. BK-stimulated IP1 formation appeared to be increased in TNFa treated cells compared to control whereas histamine-stimulated IP1 formation was not influenced. Both control and TNFa treated cells were greater than 95% viable. However, TNFa treated cells were blocked in the G1 phase of the cell cycle resulting in a decrease in DNA synthesis. This may be one mechanism for the TNFa-induced decrease in BK receptors in A431 cells. 相似文献
142.
This study describes the effects of Norplant on haemostatic function after 5 years of use in 97 women. There was a decrease in vitamin-K dependent Factors II, V, VII and reduction in fibrinolytic activity at 2 and 4 years of use. Increased platelet numbers and accelerated platelet aggregation were found throughout the 5 years of Norplant use, whilst raised alpha 2-Macroglobulin (a2-M) and antithrombin III (ATIII) antigen level were observed for up to 4 years of use. Prolonged Norplant use does not appear to activate the coagulation system and does not enhance a state of hypercoagulation. 相似文献
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A. Sethi I. Singh A. K. Agarwal D. Sareen 《Indian journal of otolaryngology and head and neck surgery》2005,57(4):283-286
The prognostic significance of the size of mastoid air cell system in the results of myringoplasty has been a matter of debate. Fifty ears with dry central perforation following C.S.O.M. were investigated. The size of mastoid air cell system was determined with planimetry of the X-ray picture and eustachian tube function was assessed using flourescein dye and nasal endoscopy. Myringoplasty was performed in all the 50 ears and postoperative results in terms of graft take up and hearing gain were assessed. The correlation between the size of mastoid air cell system, results of myringoplasty and tubal function has been discussed. The results show no correlation between the size of mastoid air cell system, postoperative results of myringoplasty and eustachian tube function. 相似文献
145.
H M Cheng O S Singh K K Kwong J Xiong B T Woods T J Brady 《Optometry and vision science》1992,69(9):698-701
We have obtained multislice magnetic resonance (MR) images of the eye and calculated ocular dimensions along the three cardinal axes: antero-posterior (A-P), equatorial, and vertical. We found no difference in the shape of hyperopic (average refractive error: +3.72 D) and emmetropic eyes, both of which had an equatorial diameter longer than the A-P and vertical diameters. Myopic eyes (average refractive error: -6.54 D) were larger than hyperopic eyes, and most had the same spheroelliptical shape as that of the emmetropic and hyperopic eyes. The results suggest that during myopic progression an overall enlargement or a radial volume expansion has occurred. 相似文献
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M P Verenkar V A Naik S Rodrigues I Singh 《Indian journal of pathology & microbiology》1992,35(2):75-80
During the period 1982-86, a total of 657 Salmonella strains were isolated from various clinical samples processed in the Microbiology laboratory of Goa Medical College, Bambolim, Goa. The strains were distributed amongst 23 different Salmonella serotypes. The commonest serotypes encountered were S.typhimurium (66%) and S.typhi (24%), the other serotypes were S.bareilly (5.4%), S.paratyphi B (1.2%), S.newport (1.2%) and S.chester (0.8%). Stool samples yielded the maximum Salmonella isolates of which the S.typhimurium was the highest followed by S.bareilly. 相似文献
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