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91.
Boris A. Dmitriev Michail V. Ovchinnikov Elena B. Lapina Galina N. Pluzhnikova Igor V. Lopyrev Anatoly Ya. Chernyak 《Glycoconjugate journal》1992,9(4):168-173
Synthetic lipopeptideN-palmitoyltyrosyl-seryl-seryl-asparaginyl-alanine, an analogue of B-mitogenic tripalmitoyl-pentapeptide fromEscherichia coli lipoprotein, was coupled with an oligosaccharide hapten fromNeisseria meningitidis lipooligosaccharide to give a glycopeptidolipid conjugate — the artificial antigen of a new type possessing the type-specific microbial determinant.Abbreviations iBu
isobutyl
- But
t-butyl
- Boc
t-butoxycarbonyl
- DCC
N,N-dicyclohexylcarbodiimide
- DMF
N,N-dimethylformamide
- DMSO
dimethylsulfoxide
- ONB
N-hydroxy-5-norbornen-2,3-dicarboximide ester
- ONp
4-nitrophenyl ester
- Pal
palmitoyl
- TEMED
N,N,N,N-tetramethylethylenediamine
- Z
benzyloxycarbonyl
- KDO
2-keto-3-deoxyoctonic acid
- Hep
L-glycero-d-manno-heptose
- TPP
S-[2,3-bis(palmitoyloxy)-(2RS)propyl]-N-palmitoylcysteinyl-seryl-asparaginyl-alanine. 相似文献
92.
A new expression vector (pBB1) has been constructed for the regulated expression of genes in Escherichia coli. Based on the pUC plasmids, the pBB 1 carries lacIts allele of the lac repressor gene. This makes it possible to control expression of cloned genes by shifting the temperature from 30°C to 42°C. Thus the vector combines advantages of the pUC plasmids with convenient regulation by temperature. Expression of a fragment of HIV-1 env gene was achieved with the help of this vector and shown by enzyme-linked immunosorbent assay and Western-blot analysis. 相似文献
93.
Davidoff MS Middendorff R Enikolopov G Riethmacher D Holstein AF Müller D 《The Journal of cell biology》2004,167(5):935-944
The cells responsible for production of the male sex hormone testosterone, the Leydig cells of the testis, are post-mitotic cells with neuroendocrine characteristics. Their origin during ontogeny and regeneration processes is still a matter of debate. Here, we show that cells of testicular blood vessels, namely vascular smooth muscle cells and pericytes, are the progenitors of Leydig cells. Resembling stem cells of the nervous system, the Leydig cell progenitors are characterized by the expression of nestin. Using an in vivo model to induce and monitor the synchronized generation of a completely new Leydig cell population in adult rats, we demonstrate specific proliferation of vascular progenitors and their subsequent transdifferentiation into steroidogenic Leydig cells which, in addition, rapidly acquire neuronal and glial properties. These findings, shown to be representative also for ontogenetic Leydig cell formation and for the human testis, provide further evidence that cellular components of blood vessels can act as progenitor cells for organogenesis and repair. 相似文献
94.
Khanova HA Markossian KA Kurganov BI Samoilov AM Kleimenov SY Levitsky DI Yudin IK Timofeeva AC Muranov KO Ostrovsky MA 《Biochemistry》2005,44(47):15480-15487
Thermal denaturation and aggregation of beta(L)-crystallin from bovine lens have been studied using differential scanning calorimetry (DSC) and dynamic light scattering (DLS). According to the DLS data, the distribution of the beta(L)-crystallin aggregates by their hydrodynamic radius (R(h)) remains monomodal to the point of precipitating aggregates (sodium phosphate, pH 6.8; 100 mM NaCl; 60 degrees C). The size of the start aggregates (R(h,0)) and duration of the latent stage (t(0)) leading to the formation of the start aggregates have been determined from the light scattering intensity versus the hydrodynamic radius plots and the dependences of R(h) on time. The R(h,0) value remains constant at variation of the beta(L)-crystallin concentration, whereas the t(0) value increases with diminishing beta(L)-crystallin concentration. The suppression of beta(L)-crystallin aggregation by alpha-crystallin is connected with the decrease in the R(h,0) value and increase in the t(0) value. In the presence of alpha-crystallin the aggregate population is split into two components. The first component is represented by stable aggregates whose size remains constant in time. The aggregates of the other kind grow until they reach the size characteristic of aggregates prone to precipitation. The DSC data show that alpha-crystallin has no appreciable influence on thermal denaturation of beta(L)-crystallin. 相似文献
95.
96.
Infections of Jute, Maize and Rice ot Revealed by the Standard Blotter Method of Seed Health Testing
In the standard blotter seed health testing of jute, maize and rice some ungerminated seeds, and seedlings with or without symptoms were eventually found to be infected by pathogenic fungi on prolonged incubation any by trans-planting seedlings from blotters to autoclaved soil in pots. 相似文献
97.
Fenoprofen, an anti-inflammatory agent, is a potent inhibitor of prostaglandin synthesis at physiological substrate concentration. I50's of 1 μM to 100 μM were obtained when the concentration of arachidonate was increased from 1 μM to 82 μM. In contrast, a small change in I50 was observed with indomethacin. Kinetic studies indicated that inhibition by fenoprofen was competitive while that of indomethacin was non-competitive. 相似文献
98.
George Notas Michail Bariotakis Vaios Kalogrias Maria Andrianaki Kalliopi Azariadis Errika Kampouri Katerina Theodoropoulou Katerina Lavrentaki Stelios Kastrinakis Marilena Kampa Panagiotis Agouridakis Stergios Pirintsos Elias Castanas 《PloS one》2015,10(3)
Severe allergic reactions of unknown etiology,necessitating a hospital visit, have an important impact in the life of affected individuals and impose a major economic burden to societies. The prediction of clinically severe allergic reactions would be of great importance, but current attempts have been limited by the lack of a well-founded applicable methodology and the wide spatiotemporal distribution of allergic reactions. The valid prediction of severe allergies (and especially those needing hospital treatment) in a region, could alert health authorities and implicated individuals to take appropriate preemptive measures. In the present report we have collecterd visits for serious allergic reactions of unknown etiology from two major hospitals in the island of Crete, for two distinct time periods (validation and test sets). We have used the Normalized Difference Vegetation Index (NDVI), a satellite-based, freely available measurement, which is an indicator of live green vegetation at a given geographic area, and a set of meteorological data to develop a model capable of describing and predicting severe allergic reaction frequency. Our analysis has retained NDVI and temperature as accurate identifiers and predictors of increased hospital severe allergic reactions visits. Our approach may contribute towards the development of satellite-based modules, for the prediction of severe allergic reactions in specific, well-defined geographical areas. It could also probably be used for the prediction of other environment related diseases and conditions. 相似文献
99.
Anatoli Tchigvintsev Hai Tran Ana Popovic Filip Kovacic Greg Brown Robert Flick Mahbod Hajighasemi Olga Egorova Joseph C. Somody Dmitri Tchigvintsev Anna Khusnutdinova Tatyana N. Chernikova Olga V. Golyshina Michail M. Yakimov Alexei Savchenko Peter N. Golyshin Karl-Erich Jaeger Alexander F. Yakunin 《Applied microbiology and biotechnology》2015,99(5):2165-2178
100.
Simone Cappello Giuseppe Mancini Alessandro Pistone Maurizio Azzaro Francesco Bottino Lucrezia Genovese Daniela Iannazzo Antonella Luciano Antonino Mamo Giovanni Neri Signorino Galvagno Santina Santisi Annamaria Visco Michail M. Yakimov 《Reviews in Environmental Science and Biotechnology》2014,13(4):369-375
Throughout the last century the increasing human activities in Antarctic region, particularly research expeditions, fishing, and tourism amplified the risk of oils spills at these high latitudes of the meridional hemisphere. A number of studies have been focused on chronic hydrocarbon contamination near Antarctic research stations revealing the presence and persistence of these human-derived contaminants. Marine ship-source oil spills in Antarctic region can have significant impacts on the marine environment. The key factors to effectively fight oil spills are a careful selection and proper use of the equipment and materials best suited to the critical local conditions. Despite the significant advances in the field of environmental recovery after an “oil spill” episode, research has recently shown that the usual techniques are often less effective than expected. This issue become much more relevant in the Antarctic case, not only for the incomparable environmental value of the Antarctic region but also for the extreme environmental conditions and the great distances from properly equipped centers, that make unfeasible sending naval vessels. Scope of the STRANgE Project is the preliminary design of a prototype floating platform, parachutable by plane, able to intervene as quickly as possible for the containment, removal and treatment/storage of the oil slick. New sorbent nanostructured materials and specialized Antarctic bacteria applications constitute the main innovations of this Project. 相似文献