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41.
The use of crown ethers for a phase transfer-catalyzed synthesis of heteroaromatic glycosides of N-acetylglucosamine was studied. The solid-liquid system and the catalysis by 15-crown-5 were found to provide for both a 100% conversion of the alpha-D-glucosaminyl chloride peracetate and a high reaction rate. The interaction of alpha-D-glucosaminyl chloride peracetate and oxadiazole and triazole mercapto derivatives capable of thiol-thione tautomerism carried out at room temperature in acetonitrile in the presence of anhydrous potassium carbonate and crown ethers was shown to lead to both S- and N-glycosides. The structures of the compounds synthesized were confirmed by X-ray analysis and 13C and 1H NMR spectroscopy.  相似文献   
42.
Based on originally designed technique of myoblast cultivation and in accordance with the approved by the Russian Ministry of Health one muscle treatment protocol of myoblast transplantation to the Duchenne muscular dystrophy patients, the first in Russia clinical trial of this gene correction method was carried out. Immunologically related myoblast cultures (30 to 90 million cells per patient) were injected after all preliminary procedures into tibialis anterior muscles of four boys selected from a group of volunteer recipients (Duchenne muscular dystrophy patients) based on the analysis of a number of surface antigens in donor–recipient pairs. The condition of the patients remained satisfactory during the whole period of post-transplantation follow-up (from 6 months to 1.5 years). Six months after myoblast transplantation the presence of donor DNA or dystrophin synthesis was demonstrated in muscle biopsies of three out of four patients. This result confirms efficacy and safety of the procedure used.  相似文献   
43.
Ageev IM  Shishkin GG 《Biofizika》2002,47(5):782-786
The temperature dependence of conductivity of water heated by a biological object, as well as electrical, aqueous and other types of heaters was studied. Substantial differences in the conductivity parameters of water heated by bioobjects and physical sources of heat were found. The effect of "memory" of water in response to the biological influence and differences in the entropy of water upon biological treatment and upon heating by physical sources of heat were revealed.  相似文献   
44.
Extracts of metanephros were studied using two-dimensional electrophoresis in human embryos at the age of 7 to 21 week of intrauterine development. Electrophoregrams show 160 to 190 protein fractions. Fractions have been identified which corresponded to actin, albumin, alpha-chain of tropomyosin, light chains of myosin. The tropomyosin zone fractions were subject to greatest changes during development. Other zones of the embryonic kidney electrophoretogram displayed, predominantly, quantitative changes of polypeptides.  相似文献   
45.
Using SDS electrophoresis and subsequent densitometry, the link proteins (LP) of proteoglycan aggregates of the knee joint hyaline cartilage, rib and/or the iliac crest cartilage were investigated. Both the control and experimental samples (n = 9 and n = 16, respectively) contained three LP with Mr 48.0 (LP-1), 44.0 (LP-2) and 41.5 KD (LP-3); however, their ratio varied within very broad limits. Low molecular weight forms of LP were also observed in the infundibulum-like deformation of the thorax. The considerable decrease of LP-3 and the elevated content of LP-2 were observed in lethal osteochondrodysplasias, which probably reflects the genetically determined disorder of limb morphogenesis, eventually resulting in the maintenance of embryonic ratio of LP. Almost all the preparations contained a protein with Mr 52 KD that was previously unknown for the LP system. The content of this protein was the highest in the exostose cartilage and in newborns. Possible mechanisms of LP heterogeneity and the significance of this parameter for the regulation of chondrogenesis and realization of certain physical properties of cartilages from different parts of the skeleton are discussed.  相似文献   
46.
A comparative analysis of the proteins in prostate tissues of the patients operated for hyperplasia (n = 7) or cancer (n = 5) was performed aiming to search for protein diagnostic markers. Differences in several minor proteins were detected using two-dimensional electrophoresis according to O’Farrel; among them, an additional protein with a molecular weight of 19 kDa and an isoelectric point of 9.0 was observed in four of the cancer cases. Mass spectrometry allowed this protein to be identified as the androgen-induced secreted protein AGR2. The possibility of using AGR2 as a diagnostic marker of prostate cancer is discussed.  相似文献   
47.
Biophysics - This study involves the mitochondrial-reticular network, which is functionally integrated into the processes that provide energy to all systems of an organism as an open, dynamic,...  相似文献   
48.
This review considers the major features of human proteins AGR2 and ERp57/GRP58 and of other members of the protein disulfide isomerase (PDI) family. The ability of both AGR2 and ERp57/GRP58 to catalyze the formation of disulfide bonds in proteins is the parameter most important for assigning them to a PDI family. Moreover, these proteins and also other members of the PDI family have specific structural features (thioredoxin-like domains, special C-terminal motifs characteristic for proteins localized in the endoplasmic reticulum, etc.) that are necessary for their assignment to a PDI family. Data demonstrating the role of these two proteins in carcinogenesis are analyzed. Special attention is given to data indicating the presence of biomarker features in AGR2 and ERp57/GRP58. It is now thought that there is sufficient reason for studies of AGR2 and ERp57/GRP58 for possible use of these proteins in diagnosis of tumors. There are also prospects for studies on AGR2 and ERp57/GRP58 leading to developments in chemotherapy. Thus, we suppose that further studies on different members of the PDI family using modern postgenomic technologies will broaden current concepts about functions of these proteins, and this will be helpful for solution of urgent biomedical problems.  相似文献   
49.
The patterns of spatial differentiation of the Early Mesozoic terrestrial biota in Eastern Europe and Australia-Tasmania demonstrate that the tetrapod faunal recovery following the Permian extinction was characterized by both global and regional heterogeneity. Local distinctions observed in the development of Early Triassic tetrapod assemblages of European Russia allow the recognition of the following realms: (1) the central and northern regions of the East European Platform (Moscow-Mezen Syncline) and the Timan-North Ural Region; (2) the southern Fore-Urals, including the Obshchii Syrt Plateau; and (3) the southern regions of the East European Platform (the slope of the Voronezh Anticline). Climatic conditions at the initial stage of the development of local communities were characterized by an increase in aridity and seasonal contrasts of climate. Therefore, terrestrial assemblages mostly concentrated in the aquatic and coastal biotopes. Accordingly, vertebrate assemblages of the region were dominated everywhere by aquatic amphibians and semiaquatic reptiles, while the accompanying palynomorph assemblages show the predominance of hygrophilous vegetation indicative of swampy mangrove setting. With respect to amphibians, a peak of local biogeographic differentiation falls on the onset of the Early Triassic and, in the case of reptiles, on the end of this time span. This change conforms to the increasing role of reptiles in the overall taxonomic diversity with time. Among the three main biogeographic units of the region, the Southern Fore-Ural Realm is distinguished by the maintenance of distinct faunal links with Gondwanan regions. The Southern Realm shows a connection with the Germanic Basin and more western Euramerican areas, which is documented for the Late Olenekian and occurred under influence of coastal marine conditions.  相似文献   
50.
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