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101.
Our objective was to determine the pattern and time course of nerve growth factor expression in an established skin equivalent model that we have used in the past to study wound healing and psoriasis phenotypes. Skin equivalents were constructed in triplicate using normal neonatal foreskin keratinocytes plated on collagen gels containing fibroblast lines. These lines were derived from five specimens of psoriatic lesions, three specimens of normal skin from patients with psoriasis, and three specimens of eyelid skin from normal donors. Immunohistochemistry and a monoclonal nerve growth factor-b antibody were used to determine the pattern of protein staining over 2 weeks. We looked at the wound healing phenotype using the skin equivalent model for 7-14 days. When keratinocytes invaginate into the dermis of skin equivalents (beginning at around 7 days of growth), dark staining of nerve growth factor was seen under the basal membrane zone, suggesting that nerve growth factor serves in the development of the basal membrane zone and the epidermis, and may influence the migration of nerves through the basal membrane zone into the regenerated skin. 相似文献
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AN Kanev MS Vorob''eva NV Shalunova LG Karpovich SV Netesov AZ Maksiutov SV Usova 《Canadian Metallurgical Quarterly》1998,2(3):47-51
The clinico-immunological examination of 57 patients with chronic bacterial prostatitis was carried out. The clinical analysis made it possible to divide the patients into 3 groups characterized by the presence of chronic inflammatory diseases of other organs which had appeared before (group 1) or after (group 2) the manifestation of the symptoms of prostatitis, aw well as by the absence of concomitant inflammatory diseases (group 3). At the same time these patients were found to have changes in their immune status, most pronounced in patients of groups 1 and 2. The clinico-immunological analysis of the patients with chronic bacterial prostatitis revealed the fact that chronic bacterial prostatitis was a chronic inflammatory process linked with changes in the immune system; these changes had the signs of secondary immunodeficiency and required immunocorrective therapy. 相似文献
104.
MV Kovina VA Selivanov NV Kochevova GA Kochetov 《Canadian Metallurgical Quarterly》1998,63(8):988-995
The two-step mechanism of coenzyme (thiamine diphosphate, ThDP) binding with two initially identical active sites of apotransketolase has been examined with a kinetic model. Cooperativity between sites in the primary ThDP binding and in the following conformational transition has been analyzed. The only reliable difference between sites is shown to be the tenfold difference in the backward rate constants of the conformational transition; this means that the cooperative interaction between sites takes place only after termination of both steps of ThDP binding in both sites. 相似文献
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ER Polosukhina SV Kuznetsov NP Logcheva TN Zabotina MR Tenuta AD Shirin GI Kaletin AG Turkina NV Tsvetaeva IuV Shishkin ZG Kadagidze ND Khoroshko MA Volkova AIu Baryshnikov 《Canadian Metallurgical Quarterly》1998,70(7):21-25
AIM: The expression of CD95(Fas/APO-1) antigen was studied on bone marrow cells of 19 MDS patients, peripheral blood blast cells of 15 acute myeloid leukemia (AML) patients, blast cells and granulocytes of 68 patients with chronic myeloid leukemia (CML)--24 in chronic, 9 in accelerated phase and 35 in blastic crisis (BC)--by indirect surface immunofluorescence assay using flow cytometry (FACScan, Becton Dickinson, USA). RESULTS: CD95(Fas/APO-1) antigen was revealed on bone marrow cells of 8 out of 19 (36.8%) MDS patients; the percentage of antigen-positive cells was 38.1 +/- 19.2%; on 45.5 +/- 22.8% of cells in 6(45%) of 15 AML patients. Fas/APO-1 antigen was totally absent in CML chronic stage; its expression was found in 34% (12 of 35) of our patients with CML BC on peripheral blood blasts and in 56% (5 of 9) on peripheral blast cells of CML patients in acceleration phase. CONCLUSION: The data on overall survival of CD95-positive MDS patients suggest that the presence of Fas antigen is a favorable prognostic sign for patients with MDS. The patients from CD95-negative group represent a risk group both for survival and AML transformation. In CML BC group the survival does not depend upon Fas-antigen expression. 相似文献
107.
Mechanisms of formalin--induced luminescence of protein-lipid complexes have been studied. Free radical reactions of lipid oxidation were shown to be necessary for generating luminescence quanta. The luminescence intensity was mostly promoted by fluorescing products formed in the reoxidized system protein-lipid. Formalin-induced flash of luminescence in these systems may evidently serve as an express-method for analysing protein sample contamination with unsaturated lipids. 相似文献
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A. C. Labrujere T. O. Klassen W. Th. Wenckebach C. T. Foxon 《Journal of Infrared, Millimeter and Terahertz Waves》1988,9(12):1057-1066
Far infrared spectroscopy experiments on the shallow donor states of GaAs:Si are presented. Transitions between shallow donor levels are induced by F.I.R. radiation from an optically pumped molecular gas laser. The measurements are performed by measuring the electrical conductivity of the GaAs:Si sample at fixed laser frequencies by sweeping an external applied magnetic field up to 12 T. In total about 30 different transitions are observed using radiation between 60 μm and 1.8 mm. In low magnetic fields and at high frequencies a series of photoconductivity signals are observed, which we ascribe to transitions from the ground state towards bound donor levels with hydrogen quantum numbers n, l=n?1, and m=n?1. 相似文献
110.