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991.
Inflammation and coagulation cannot be considered as two separate processes, since there are several connecting points making them part of unique, defensive host response. The endothelium can be considered as the first link between inflammation and coagulation, since damaged endothelium during inflammation represents a surface where proteins involved in both coagulation and the development of inflammation are expressed. During inflammation, cytokines modulate the coagulation system by downregulating the expression of thrombomodulin and the activation of protein C pattern but, at the same time, they induce the expression of tissue factor, modifying, in this way, the balance between procoagulant and anticoagulant activities. At the same time, at the site of tissue injury, platelets become activated and release several mediators that modify tissue integrity. Thrombin, formed following activation of the coagulation cascade, is essential to promote haemostasis but also stimulates several cell functions, including chemotaxis and mitogenesis, which are responsible for the spreading of the lesion and the tissue repair process. Therefore, in the study of inflammation the involvement of the coagulation pathway has to be taken into account, since the interaction between coagulation and inflammation pathways is a critical issue. 相似文献
992.
993.
K Jin-no M Tanimizu I Hyodo Y Nishikawa Y Hosokawa H Endo T Doi K Mandai H Ishitsuka 《Canadian Metallurgical Quarterly》1998,82(7):1260-1267
BACKGROUND: Platelet-derived endothelial cell growth factor (PD-ECGF) is an angiogenic factor that is expressed in various cancer tissues. Little is known regarding plasma PD-ECGF levels in patients with chronic liver disease such as chronic hepatitis (CH), cirrhosis, and hepatocellular carcinoma (HCC) with cirrhosis. The expression of PD-ECGF in HCC tissues also remains to be clarified. METHODS: Plasma PD-ECGF levels in patients with chronic liver disease were determined with an enzyme-linked immunoadsorbent assay system using the mouse monoclonal antibodies specific to PD-ECGF. These were cross-sectionally compared among groups of normal persons, CH, cirrhosis, and HCC patients. The HCC patients were classified into two groups based on TNM stage: early and advanced stage disease groups. PD-ECGF expressions in HCC tissues were immunohistologically examined. RESULTS: The plasma PD-ECGF levels from the normal individuals and those with CH, cirrhosis, and HCC specimens were 4.2+/-0.5, 4.3+/-0.6, 4.6+/-1.1, and 6.0 +/-2.5 U/mL, respectively. The plasma PD-ECGF concentration was highest in HCC (P < 0.05). No significant difference was found among the normal subjects, CH, and cirrhosis specimens. Plasma PD-ECGF concentrations were significantly higher in the advanced stage disease HCC group compared with the early stage disease group (6.75+/-2.62 U/mL vs. 4.19+/-0.34 U/mL) (P < 0.05). Immunohistochemical expression of PD-ECGF in HCC cells increased significantly compared with normal liver cells (P < 0.05). CONCLUSIONS: Circulating PD-ECGF plasma level might be a new tumor marker for progression in patients with HCC. Immunohistological findings correspond to elevation of the plasma PD-ECGF in HCC patients. It is possible that increased production of PD-ECGF in HCC cells causes abundant neovascularization. 相似文献
994.
C Sergi K Jundt S Seipp T Goeser L Theilmann G Otto HF Otto WJ Hofmann 《Canadian Metallurgical Quarterly》1998,29(6):861-871
BACKGROUND/AIMS: The aim of the study was to assess the impact factor of HCV and HGV in fulminant hepatic failure. METHODS: The 5'-untranslated regions of HCV RNA and HGV RNA and a segment of the core antigen sequence of HBV were amplified after extracting the nucleic acids from snap-frozen tissue aliquots from explanted livers of 26 consecutive patients undergoing orthotopic liver transplantation for fulminant hepatic failure preoperatively diagnosed as either autoimmune (n=2), HAV/HBV (n=8), toxic (n=4) or aetiologically unknown (n=12). RESULTS: HCV RNA was detected in five of 26 (19.2%) livers with fulminant hepatic failure. All five HCV RNA-positive livers belonged to the group of non-toxic, non-autoimmune liver failure (n=20), three of them were found in the group of liver failure with unknown aetiology (n=12) and two in the group of HBV-associated liver failure (n=7), making an HCV incidence of 25%, 25% and 28.6%, in the different groups, respectively. HGV RNA was detected in 10 of 17 (58.8%) explants and in all four groups of fulminant hepatic failure as defined preoperatively. HBV DNA was identified in six livers of 26 patients (23.1%) with fulminant hepatic failure. Neither HCV RNA nor HBV DNA was detected in the livers of patients with toxic or autoimmune fulminant hepatic failure. CONCLUSIONS: These results indicate that HBV and HCV, but not HGV, play an aetiologic role in fulminant hepatic failure. HCV-positive cases were concentrated either in the group of otherwise unexplained fulminant hepatic failure or in the group of HBV fulminant hepatic failure. HGV-positive cases, on the other hand, were found within all four preoperatively defined groups, indicating a role as cofactor rather than as single aetiologic agent. 相似文献
995.
Determination of cytochrome P450 2E1 activity was carried out via hydroxylation of the synthetic substrate p-nitrophenol to p-nitrocatechol. Crude microsomal preparation isolated from rat liver served as source for cytochrome P450 2E1. Under assay conditions guaranteeing a linear course of the reaction the cytochrome P450 2E1 was stimulated in the presence of a 10(-6) dilution of As2O3 corresponding to 0.915 microM final concentration compared with control. All other concentrations of As2O3 used inhibited the enzyme activity more or less drastically. Furthermore, we used this enzyme system to study the influence of arsenicum album (As2O3) and potassium cyanatum (KCN) in homeopathically prepared (i.e., by consecutive 1:10 steps) and conventional dilutions. We found significant differences between the effects caused by homeopathic potencies (D) and equally concentrated dilutions on catalytic activity of cytochrome P450 2E1. Such differing effects were observed in the case of arsenicum album (As2O3) between D4/10(-4) and D6/10(-6) and in the case of potassium cyanatum (KCN) between D6/10(-6) and D12/10(-12). When we used glutathione-S-transferases and uricase we also found different effects mediated by potencies and conventional dilutions. The results obtained suggest that these three enzyme systems are appropriate detection systems to hunt out differing effects of differently prepared dilutions of specific test substances. 相似文献
996.
The a.c. conductivity of the proteins lysozyme and subtilisin, both in their active and inactive or inhibited forms were determined theoretically. For this, quantum mechanical calculations and a random walk theory were used. The conclusions are that these enzymatic proteins can easily transport electrons which is most probably important in their role as catalysators of biochemical reactions. The electron transport is sensitive to three-dimensional changes of the active sites of these enzymes which have more flexibility than the whole molecule. Therefore, the flexibility of the active sites of enzyme catalysts is not only important for the conformational fitting with the reactants, but also strongly influences the transport in biochemical reactions. 相似文献
997.
W Eggert-Kruse G Rohr H Kerbel B Schwalbach T Demirakca K Klinga W Tilgen B Runnebaum 《Canadian Metallurgical Quarterly》1996,11(4):784-789
To determine the clinical usefulness of Acridine Orange (AO) staining of spermatozoa as a screening test for the evaluation of semen quality during basic infertility investigation, semen smears from 103 randomly chosen males of subfertile couples were examined. The median duration of infertility was 4.5 years (range 1-15) and the median age was 33 years (range 21-43). The outcome of AO staining ranged from 5 to 81%, with a median of 24%, green fluorescent spermatozoa. Results were not significantly related to the parameters of semen analysis (sperm count, motility, standard morphology, viability, pH and volume, as well as fructose concentration and number of found cells) or to local sperm antibody testing and semen cultures. Fluorescence after AO staining was also not related to sperm functional capacity (evaluated using sperm-mucus interaction tests in vitro and in vivo), or the medical history of the patient. No significant differences in the AO test outcome were seen in patients with explained and unexplained infertility, or with regard to subsequent fertility [with a median value of 21% (range 5-46) green fluorescence in the fertile group, compared with a median value of 28% (range 9-81) green fluorescence in the other men]. The results of this prospective study indicate that under the usual conditions of conception, the AO test is not clinically useful as a screening procedure to determine semen quality during basic infertility investigation. 相似文献
998.
Problems of gluing parts made of silicon nitride are considered. The quality of glued joints is estimated. The effects of the composition (the types of binder and filler), the technological parameters (thickness of the joint, roughness of the glued surfaces, porosity of the parts), and the test conditions are considered. The technology for gluing parts made of RBSN and HP parts made of Si3N4 and results of tests of glued joints are described.Translated from Ogneupory, No. 4, pp. 18 – 20, April, 1996. 相似文献
999.
V. E. Gul O. A. Sdobnikova A. L. Peshehonova L. G. Samoilova O. A. Khanchech A. I. Suvorova 《Polymer Engineering and Science》1993,33(22):1489-1493
Reported is an attempt to attain orientation of macromolecules during extrusion of films of cellulose derivatives that led to the liquid-crystalline state of a polymer and resulted in enhanced film strength. 相似文献
1000.
V. F. Shevchenko A. A. Petrov V. G. Petrov 《Journal of Infrared, Millimeter and Terahertz Waves》1993,14(9):1755-1768
A basic principle of pulse radar reflectometry is considered in this paper. A numerical analysis is performed in order to study errors appearing due to the expansion of a microwave pulse reflected from the plasma. A block diagram of the basic pulse radar scheme and its overall performance is presented. The first experimental results obtained on T11-M tokamak are discussed. An improved pulse radar scheme with cross-detection is considered. The results of bench test experiments and future applications of this scheme are discussed. 相似文献