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991.
The effect of L-lysine-alpha-oxidase from a representative of the Trichoderma genus on the humoral immune response to protein antigens was studied. It was shown that repeated fife-fold intravenous administrations of L-lysine-alpha-oxidase in a dose of 35 U/kg had no depressive action on the humoral immunity. The enzyme had no suppressive effect on the delayed type hypersensitivity to xenogenous erythrocytes. The use of L-lysine-alpha-oxidase in a therapeutic dose or in a twice as higher dose had no reliable effect on the leukocyte migration capacity vs. the control.  相似文献   
992.
We studied concentrations of cortisol, its precursors and active form in human blood and relation to the changes in concentration of central and peripheral hormonal regulators (total 36 parameters) in healthy male volunteers aged 18-72 y.o. The study demonstrated a significant decrease in blood concentrations of unutilazed cortisol precursors (pregnenolone and progesterone) with advanced age accompanied by maintenance of total and free cortisol concentrations. We found age-related decrease in ACTH level that is a known hypophysial stimulant of cortisol and cortisol precursor synthesis in adrenal glands. Cortisol and ACTH levels in study population had different correlation behavior in relation to central and peripheral regulators for hormonal axes. CONCLUSION: cortisol level remains stable with advanced age in males despite the decrease in steroidogenic activity and blood ACTH level. This may be due to the imbalance in the regulation of cortisol and ACTH production by central and peripheral regulators especially by hormones of reproductive and somatotrophic axes.  相似文献   
993.
Telomeres are the ends of the chromosomes and represent repeated DNA sequence and protein complex. Telomeres shorten with each cell division, which limits proliferative potential of cells. There is a great progress in clinical application of telomere length now. Additional characteristic of stem cell proliferation activity estimated by telomere length can be an informative indicator of transplant quality. In this work, we analyzed 14 cord blood samples by flow-FISH, ELISA and gematologycal analisator, and also the number of CD34 + CD45dim cells. Average telomere length of leukocytes fraction CB cells was 20.4-4.9 % respectively the control cells 1301 (T-cell lymphoblastic leukemia).  相似文献   
994.
This paper examines the structural and mechanical properties of composite materials based on chitosan and micro- and nanoparticles of Na-montmorillonite and possibility of application for cultivation and targeted delivery of mesenchymal stem cells and regenerative cells. It's have been shown by addition of Na-montmorillonite biomaterial acquires stability of structural and mechanical properties in the sterilization process the handling of liquid media in cell culture. In vitro studies using dermal fibroblasts and adipose tissue mesenchymal stem cells demonstrated that this material has a set of properties to ensure matrix biocompatibility.  相似文献   
995.
A comparative analysis of the genome of V. cholerae O139 strains isolated in Russia's territory from patients with cholera and from the environment showed essential differences in their structures. The genome of clinical strains possessed all tested genes associated with virulence (ctxAB, zot, ace, rstC, rtxA, hap, toxR and toxT) and the at-tRS site for the CTXp phage DNA integration. As for the O139 V. cholerae chromosome strains isolated from water, 70% of the studied genes (ctxAB, zot, ace, rstC, tcpA, and toxT) and the attRS sequence were not detected in them. A lack of the key virulence genes in O139-serogroup "water" vibrios, including genes of toxin-coregulated adhesion pili. (that are receptors for the CTXp phage), and of the attachment site of the above phage are indicative of that the O139 V. cholerae strains isolated from open water sources located in different Russia's regions are epidemically negligible.  相似文献   
996.
The conversion of lignocellulose to valuable products requires I: a fractionation of the major components hemicellulose, cellulose, and lignin, II: an efficient method to process these components to higher valued products. The present work compares liquid hot water (LHW) pretreatment to the soda pulping process and to the ethanol organosolv pretreatment using rye straw as a single lignocellulosic material. The organosolv pretreated rye straw was shown to require the lowest enzyme loading in order to achieve a complete saccharification of cellulose to glucose. At biomass loadings of up to 15% (w/w) cellulose conversion of LHW and organosolv pretreated lignocellulose was found to be almost equal. The soda pulping process shows lower carbohydrate and lignin recoveries compared to the other two processes. In combination with a detailed analysis of the different lignins obtained from the three pretreatment methods, this work gives an overview of the potential products from different pretreatment processes.  相似文献   
997.
A new spectrophotometric procedure was developed for the quantitative determination of fucoidan and alginic acid and used for their analysis in extracts from biomass of 17 species of brown algae collected from coastal waters of the Kamchatka peninsula. In addition, neutral monosaccharides and mannitol were determined in the hydrolysis products of the alga biomass samples. The polysaccharide composition was shown to substantially depend on the algal species. The alginic acid content was maximal in the Alaria marginatablades; all the other representatives of the order Laminariales also are useful sources of this polysaccharide. At the same time, the fucoidan content is rather low in Laminariales. The highest content of fucoidan was found in Saundersella simplex, but Chordaria flagelliformisand Fucus evanescensare more practical fucoidan sources; the available supplies and the sugar composition make the latter alga the most suitable for the complex processing to prepare mannitol, fucoidan, and alginic acid.  相似文献   
998.
A new variant of thermometry is described. The new technique is intended for studying poorly understood thermal states and deciphering the mechanisms of adaptive reactions of healthy humans, as well as correcting of the heat balance of patients in clinical medicine.  相似文献   
999.
1000.
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