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101.
The distribution of modular nanotransporters (MNTs) that are used to deliver drugs into melanoma cell nuclei after their intravenous administration into mice with Cloudman S91 melanoma was studied. The modification of MNTs with polyethylene glycol (PEG) of different length and their administration during the treatment with docetaxel, nitroglycerin, and excess of nonspecific MNTs leads to an improved accumulation of MNTs in the tummor. Among the variants studied, the MNT with attached PEG with Mr 40 kDa exhibited the best properties.  相似文献   
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The current trend of combining state of the art technologies with quondam treatments in order to overcome existing gaps in the clinical area determined an increased interest into polyphenols, common dietary phytochemicals, for the prevention and treatment of chronic diseases, especially cancer. The reemergence of polyphenols in the cancer field is sustained by advanced-omics technologies able to identify coding and non-coding genes and their related signaling pathways modulated by natural compounds. Identification of the structural correspondence between interacting molecules will allow the development of more targeted and informed therapeutic strategies for cancer management.  相似文献   
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Aspects of the biology and ecology of Apanteles evonymellae (Bouché), a parasitoid of the poplar clearwing moth, Paranthrene tabaniformis (Rott.), were studied during the period 1987–96. One-year-old poplar ( Populus spp.) shoots infested with P. tabaniformis larvae were collected during the winter months at 11 localities in Bulgaria and examined in the field and laboratory. Apanteles evonymellae was recorded in all areas studied in Bulgaria. The mortality of P. tabaniformis caused by this parasitoid in various regions of Bulgaria varied from 2.4 to 35.4%; the average for the country was 17.3%. Laboratory observations showed that A. evonymellae is a solitary endoparasitoid of the poplar clearwing moth. It develops in early-stage (first- to fourth-instar) host larvae and overwinters as a larva in the host. Apanteles evonymellae is bivoltine, but only the second generation is associated with P. tabaniformis . In the field, adult parasitoids of first generation appear in April about 1 month before the emergence of P. tabaniformis . The longevity of A. evonymellae adults is a maximum of 6 days. Therefore, in the spring, A. evonymellae cannot attack neonate P. tabaniformis larvae and must develop in alternative hosts. Prior to their death the parasitized P. tabaniformis larvae construct conical structures, 'refuges' of frass and silk threads over the external openings of the larval galleries. Apanteles evonymellae pupates in these refuges after the host's death. This modified behaviour of the parasitized host larvae probably protects the pupae of A. evonymellae from hyperparasites and predators.  相似文献   
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Hydrodynamic shearing of chromatin in the presence of Mg2+ ions produces two discrete types of particles: (1) molecules of completely free DNA which comprise 20–23% of the total DNA and (2) histone-covered DNA molecules which contain all five histone fractions. The average length of free DNA molecules depends on the intensity of shearing and can be as high as 1000 base pairs or more. Shearing of chromatin in the absence of Mg2+ produces a heterogeneous population of DNP particles; no free DNA is liberated. However, the addition of Mg2+ to this preparation results in appearance of free DNA molecules and in a complete restoration of the above bimodal distribution.These findings support a previously proposed asymmetric hairpin model of DNA packing in the chromatin [1–3].  相似文献   
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