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21.
M R Giovagnoli P Di Fraia A Manna V Marafini C Valli P Marchei A Vecchione 《The International journal of biological markers》1989,4(1):13-17
We tested the presence of tumour polypeptide antigen (TPA) in lower urinary tract cells from 59 workers exposed to known bladder carcinogens and from 30 control subjects. We then correlated immunocytological expression and serum TPA levels. Lower urinary tract cells from 31 subjects gave either moderately or strongly positive immunocytological stains. Five also had high serum TPA. The detection of TPA by cytology and in serum differed significantly in workers exposed to cancer agents and the control group. 相似文献
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We have previously reported that in vitro HCV infection of cells of hepatocyte origin attenuates complement system at multiple steps, and attenuation also occurs in chronically HCV infected liver, irrespective of the disease stage. However, none of these regulations alone completely impaired complement pathways. Modulation of the upstream proteins involved in proteolytic processing of the complement cascade prior to convertase formation is critical in promoting the function of the complement system in response to infection. Here, we examined the regulation of C2 complement expression in hepatoma cells infected in vitro with cell culture grown virus, and validated our observations using randomly selected chronically HCV infected patient liver biopsy specimens. C2 mRNA expression was significantly inhibited, and classical C3 convertase (C4b2a) decreased. In separate experiments for C3 convertase function, C3b deposition onto bacterial membrane was reduced using HCV infected patient sera as compared to uninfected control, suggesting impaired C3 convertase. Further, iC3b level, a proteolytically inactive form of C3b, was lower in HCV infected patient sera, reflecting impairment of both C3 convertase and Factor I activity. The expression level of Factor I was significantly reduced in HCV infected liver biopsy specimens, while Factor H level remained unchanged or enhanced. Together, these results suggested that inhibition of C3 convertase activity is an additional cumulative effect for attenuation of complement system adopted by HCV for weakening innate immune response. 相似文献
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25.
T. Zaccheo D. Giudici E. Di Salle 《The Journal of steroid biochemistry and molecular biology》1993,44(4-6):677-680
The antitumor effect of exemestane (FCE 24304), an irreversible aromatase inhibitor, given alone or in combination with tamoxifen, was investigated in rats with 7, 12-dimethylbenzanthracene (DMBA)-induced mammary tumors. The compounds were given once daily, 6 days a week for 4 weeks. Exemestane, given at the dose of 20 mg/kg/day s.c., induced 26% complete (CR) and 18% partial (PR) tumor regressions, compared to 0% CR and 6% PR observed in controls. Tamoxifen, given at 1 mg/kg/day p.o., induced 16% CR and 13% PR. The combined treatment caused 41% CR and 16% PR, thus resulting in a higher antitumor effect than either single treatment. The apperance of new tumors was reduced by each single treatment and almost totally prevented by the combined treatment. Serum prolactin (PRL) levels, assayed 4 h after the last dose, were unchanged in the group treated with the combination, whereas tamoxifen alone caused a slight increase of serum PRL. These results indicate that estrogen deprivation through aromatase inhibition and estrogen receptor antagonism causes a better inhibition of DMBA-induced mammary tumors than either treatment modality alone. 相似文献
26.
D Di Lorenzo G Ruggeri C Iacobello S Belloli M Gion D T Zava S Ghielmi A Albertini 《The International journal of biological markers》1991,6(3):151-158
A radioreceptor assay (RRA) for the determination of total estrogen activity, was set up and used to assess the possible presence of exogenous molecules with estrogen activity in serum; a comparison was made with the specific radioimmunoassay (RIA) for the endogenous estrogen 17-B estradiol (17-B-E2). The assay was first performed on sera from healthy people taking estrogens in the form of oral contraceptives or lotions for local application whose total estrogenic activity in the blood was assumed to be abnormal. The assay was then performed on serum from 98 patients with early breast cancer and 20 patients with metastasis, not undergoing hormone therapy. A higher estrogen activity was found in 2.5% of sera compared to the activity found using the RIA method which is specific for endogenous estrogen 17-B-E2, the RRA/17-B-E2 ratio being higher than 3. Increased estrogen activity was found in 10% serum samples from digoxin treated cardiopathic patients, with an RRA/17-B-E2 ratio ranging from 4.4 to 20. The RRA assay could prove useful for showing up exogenous estrogen activity from various sources (drugs, food) in sera of people in whom estrogen stimulation could be potentially dangerous (i.e. in patients with hormone-sensitive tumors). This exogenous activity could support a certain degree of neoplastic stimulation and, therefore, unfavourably condition the patients' therapeutic response. 相似文献
27.
A retrovirus carrying the polyomavirus middle T gene induces acute thrombocythemic myeloproliferative disease in mice. 总被引:2,自引:0,他引:2
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A Fusco G Portella M Grieco G Tajana G Di Minno N Polli A Pinto 《Journal of virology》1988,62(1):361-365
Mice inoculated with an artificially constructed retrovirus carrying the middle T gene of polyomavirus develop acute myeloproliferative disease with severe thrombotic and hemorrhagic disorder and impaired platelet function. The megakaryocytic lineage appears to be a target for polyoma-murine leukemia virus infection and middle T gene expression. This newly described disease represents a unique model system for studying disorders of the megakaryocytic lineage. 相似文献
28.
29.
Hubert Schwabl Eberhard Gwinner Silvano Benvenuti Paolo Ioal 《Ethology : formerly Zeitschrift fur Tierpsychologie》1991,88(1):35-45
We caught dunnocks at a wintering site near Pisa/Italy prior to their departure for breeding territories and held them indoors north of this site (Andechs/Germany) on a simulated photoperiod of 52.5 °N. After birds had gone through a reproductive cycle and postnuptial moult they developed migratory restlessness in autumn. At this time one group was transferred back to the previous wintering site (Pisa) where birds were held in individual activity cages in an outdoor aviary, allowing them to perceive as much environmental information as possible. A second group was transferred to a control site near Tour du Valat/France of approximately the same latitude and climate, but different longitude and held in an identical aviary. The diurnal activity pattern changed after transfer back to the previous wintering site, but not after transfer to the control site. Specifically, the amount of morning activity was reduced while afternoon activity was increased. This effect was restricted to those individuals that had been developing nocturnal migratory restlessness the previous spring. It was absent in individuals without migratory restlessness in spring, indicating that the different patterns were not due to unspecific effects from the testing sites. These results are consistent with the hypothesis that birds were able to derive information about their locality and to recognize their previous wintering site, resulting in suppression of migratory state by experience. The results are not definitely conclusive, however, because of several difficulties in the interpretation of perch-hopping activity, which are discussed in detail. 相似文献
30.
One antigen, one gold? A quantitative analysis of immunogold labeling of plasma membrane 5'-nucleotidase in frozen thin sections 总被引:3,自引:0,他引:3
K E Howell U Reuter-Carlson E Devaney J P Luzio S D Fuller 《European journal of cell biology》1987,44(2):318-327
We present an evaluation of the efficiency of immunogold labeling for a low abundance plasma membrane protein. Several independent methods were used to determine the density of 5'-nucleotidase on the plasma membrane of the Fao cell. These methods include morphometry in combination with either enzymology or cell surface radiometric assay. Immunocytochemistry of frozen thin sections with either single or double layers of antibody and visualized with protein A complexed with 5 nm colloidal gold was used to estimate the same density. The application of a balance sheet to immunogold labeling demonstrates that the labeling is never quantitative. For example, labeling of the cell surface is always greater than labeling on the section. We show that departures from the "one antigen, one gold" ideal are systematic, so that an efficiency can be calculated and quantitative results can be obtained. The ability to obtain reliable quantitative results from immunogold labeling extends the utility of this already powerful technique. 相似文献