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A new series of N-(substituted)benzyl-1,8-naphthalimides 4, structurally related to the previously reported thymidylate synthase (TS) inhibitor naphthaleins 3, were synthesized and compounds tested for their inhibition of several species of TS. Moreover, their in vitro cytotoxicity together with antimycotic and antibacterial properties were assayed. While no activity was detected in the antibacterial tests, the m-nitro (4ae) and the p-nitro (4af) derivatives were found able to partially inhibit TS at low micromolar concentrations. Introduction of nitro or (substituted)-amino groups in position 4 of the naphthalic ring always led to less active compounds.  相似文献   
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59 angiomyolipomas were studied: immunohistochemistry (IHC) was used in 24 cases, electron microscopy (EM) in 6 cases. 57 tumors had a typical structure, 2 did not contain fat component. Premelanosomes were found by EM in one tumor. Smooth muscle actin was found in all tumor cells. Involvement of lymph nodes was observed in 2 patients. Histogenesis of this tumor is discussed.  相似文献   
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The aim of this work, that was carried out using Wistar rats, was to characterize the response of neurons of different morphofunctional types to amphetamine administration and to study the possibility of correction of these changes by delta-sleep inducing peptide (DSIP). Single intraperitoneal injection of 60 microg/kg of DSIP following a long term amphetamine administration (2.5 mg/kg for 3 weeks) was shown to result in normalization of brain metabolism, that was disturbed by the drug. The correcting DSIP effect was found in rat brain structures judging by the parameters of the state of proteins in neurons of sensomotor cortex and caudate nucleus and by the activity of enzymes of neurotransmitter metabolism, such as type A and B monoamine oxidases and acetylcholine esterase, that was determined in subfractions of the same brain structures. DSIP modulating effect in phenamine stereotypy supports its role as an adaptogen of intercenter relations in CNS pathology.  相似文献   
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Morphology of microparticles of the microencapsulated measles vaccine was studied by cryofractography, transmission electronic microscopy and by atomic force microscopy; co-polymers of polyacrylic acid and of sodium-alginate (spermidine) complexes were used as the matrix. The different-composition microcapsules had clear-cut borders and a certain range of sizes; but they were different in morphology, and their structures and densities varied identically with regard for a medium acidity, which is apparently preconditioned by some conformation-type alterations of matrix molecules. The studied preparations can, probably, protect the viral material in the stomach aggressive medium and release the material to ensure its contact with the intestine lymph tissue; thereof, they can be referred to as promising for further study of mucosal vaccines.  相似文献   
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The laboratory verified cases of Crimean-Congo hemorrhagic fever (CCHF) in the piedmont steppes of the North Caucasus (Malgobeksky District, Republic of Ingushetia) are first described. The source of the first infection was Ixodidae ticks; three subsequent sources were contacts with the bloody discharges from patients. CCHF virus genome was detected in the blood of the cattle from an epidemic focus and in the pools of the Ixodes ticks Haemaphysalis parva Neum., 1897 and Boophilus annulatus Say, 1821, taken from cattle. The problem of including the piedmont steppes of the North Caucasus into the CCHF nosological area is discussed.  相似文献   
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