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91.
92.
AV Feofanov VA Ole?nikov AB Tuzikov AI Ianul' EIu Kriukov NV Bovin IR Nabiev 《Canadian Metallurgical Quarterly》1997,23(11):910-918
Neoglycoconjugates based on polyacrylamide and sialic acid with N-acetylneuraminic acid or sialooligosaccharides as side chains were studied by surface-enhanced Raman scattering (SERS) spectroscopy. It had previously been found that these polymers can effectively inhibit influenza virus adhesion. This study revealed the possibility to evaluate, based on the intensity of SERS signals, the overall availability for interaction and the conformational freedom of sialic acid residues in glycoconjugates. The dependence of these two factors on the structure and density of sialylated side chains was studied. The uniformity of distribution of sialylated side chains in conjugates was shown. Comparison of the results of the SERS spectroscopic study of the conjugates and the data on their inhibitory effect on the adhesion of specific strains of influenza virus allowed the identification of the conjugates for which the availability and conformational freedom of sialic acid are the main factors determining their inhibitory properties. A conclusion was also reached about the predominance of one of the mechanisms (competitive inhibition or steric stabilization) in the inhibitory properties of the specific conjugates. 相似文献
93.
Albuquerque Gabriela B. M. L. Silva Valdir P. Rodrigues Joo Paulo C. 《Fire Technology》2022,58(2):737-775
Fire Technology - Reinforced concrete beams lose resistance at high temperatures and so as to guarantee their good performance, it is mandatory to consider this accidental action in design. As an... 相似文献
94.
Karina Cardoso Tramonte João Gustavo Provesi Iolanda Moreira Dutra Albuquerque E Silva Aureanna Nairne Negrão Murakami Marcelo Maraschin Renata Dias De Mello Castanho Amboni Edna Regina Amante 《International Journal of Food Science & Technology》2011,46(9):1871-1877
The heart of palm is a food extracted from several species of palm trees. Only 10–20% of the raw material is transformed into canned hearts of palm, therefore this agro‐industry generates a large quantity of solid residue. The aim of this work was to extract and characterise a juice produced from this solid residue. This extract is compared with the traditional fruit juices (orange and pineapple juices), obtaining higher contents of minerals, such as magnesium (22.80 mg/100 g) and potassium (276.90 mg/100 g), phenolic compounds (gallic, 3,4‐dihydroxybenzoic, chlorogenic, syringic and caffeic acids) and high free radical scavenging capacity (expressed as 2,2‐diphenyl‐1‐picrylhydrazyl), which suggest high antioxidant activity. Additionally, a new soft drink was formulated using this king palm juice as its main ingredient. The soft drink samples formulated with this juice had high sensory acceptability and high intention of consumption, which suggests an important and low‐cost application for this industrial residue. 相似文献
95.
João Fhilype Andrade Souto‐Maior Adriano Valim Reis Liliane Neves Pedreiro Osvaldo Albuquerque Cavalcanti 《Polymer International》2010,59(1):127-135
Pectin was chemically modified with different amounts of trisodium trimetaphosphate (STMP) in aqueous solution (pH = 12), thereby giving a material with reduced water solubility. The physiochemical characterization of this new material was carried out through Fourier transform infrared and thermogravimetric analyses. Phosphated pectin (Pect‐STMP) together with prebiotic (oligosaccharide) were incorporated into an aqueous dispersion of polymethacrylate (Eudragit® RS 30 D) in order to obtain free films using a casting process (50 °C) on a Teflon plate. The free films were evaluated using water vapour transmission, average swelling index in simulated gastric fluid (SGF) and simulated intestinal fluid, scanning electron microscopy and a diffusion study with theophylline in buffer solution with and without pectinolytic enzyme. The results suggest that the new material can be used in the coating process for oral solid‐reservoir systems, to prevent the premature release of drugs in SGF (pH = 1.2). Furthermore, the presence of both Pect‐STMP and oligosaccharide favours the specific degradation of the pellicle by the action of the enzymes produced by colonic microflora. The material obtained in this work has the potential to be applied in devices for drug delivery in the colon, making possible modified release of drugs. Nevertheless, subsequent colon‐specific experiments in vivo need to be carried out in order to confirm the possible application of this new material. Copyright © 2009 Society of Chemical Industry 相似文献
96.
AV Shabunin 《Canadian Metallurgical Quarterly》1997,156(6):77-79
Children during the first few years of their lives, presenting with lymphohypoplastic diathesis were studied for their blood serum content of sodium, potassium, chlorine. Relationship was found of the electrolyte balance to the processes of the lipid peroxidation, activity of the hormonal link of the antioxidant defence system. 相似文献
97.
98.
IuP Slizhenko AV Beliaev AM Zaremba TN Platonova 《Canadian Metallurgical Quarterly》1997,69(5-6):183-190
The fibrinolytic process in the plasma of patients operated for abdominal haemorrhages have been investigated. The results allowed to conclude that the blockade of fibrinolysis did not effect on the course of the disease. The high level of the inhibitors and of the platelets hypoaggregation can be considered as a cause increased of the recurring gastrointestinal haemorrhages. It was demonstrated that the probability of DIC-syndrome development increased at the aggravation of the patient's state after the operation. 相似文献
99.
SKh Degtyarev NA Netesova MA Abdurashitov AV Shevchenko 《Canadian Metallurgical Quarterly》1997,187(2):217-219
1. Ovomucoids were purified from Muscovy duck, domestic duck and domestic goose. 2. Peptide maps of cyanogen bromide-cleaved ovomucoids from Muscovy duck and domestic duck were very similar to one another, but differed from that of goose. 3. Muscovy duck ovomucoid showed the same protease inhibitory pattern as ovomucoid from domestic duck, inhibiting trypsin in the molar ratio of 1:2 and chymotrypsin 1:1. 4. Inhibitory complexes could be detected between chymotrypsin and ovomucoid from both Muscovy and domestic duck, but not from goose, by using non-denaturing gels. 5. No complexes could be detected between DFP-inactivated chymotrypsin and any of the ovomucoids. 6. The results show that of ovomucoid from Muscovy duck more closely resembles that from domestic duck than goose. 相似文献
100.
The complete sequence of ART-CH, a recently found chicken retrotransposon (A. V. Gudkov, E. A. Komarova, M. A. Nikiforov, and T. E. Zaitsevskaya, J. Virol. 66:1726-1736, 1992), was characterized. ART-CH has the structure of a 3,300-bp-long provirus, including two 388-bp long terminal repeats (LTRs) (U3, 245 bp; R region, 17 bp; and U5, 126 bp), a tRNA(Trp)-binding site, and a polypurine tract, similar to avian leukosis viruses. At least some of the approximately 50 genomic copies of ART-CH are transcribed into polyadenylated RNA, which is initiated and terminated at the expected sites within the LTRs. In contrast to the regulatory sequences involved in proviral expression and replication, the internal regions of ART-CH seem to be completely defective. Several short regions of homology with avian leukosis virus genes, most of which encode gag-related sequences, were found among different reading frames of ART-CH, which are not organized like regular retroviral genes. Both sequence analysis and restriction fragment length polymorphism analysis revealed a high degree of sequence (97% homology) and structural similarity among members of the ART-CH family, indicating their common origin and recent penetration into chicken DNA. ART-CH sequences were detected in mouse cells infected with Rous sarcoma virus produced by an ART-CH-expressing Rous sarcoma. These data are consistent with the hypothesis that ART-CH belongs to a class of defective retrotransposons whose replication strategy requires the use of helper viruses. They might originate from an avian leukosis virus-related retrovirus which completely lost its coding capacities as a result of multiple mutations and deletions. These features apparently group ART-CH with the VL30 retrotransposons of rodents. 相似文献