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21.
Claudia A. Zacharias Gabriel Manrique Sebastián A. Minoli 《Medical and veterinary entomology》2023,37(1):76-85
Triatomines display most of their activities during the night. Before sunrise, they search, select and occupy adequate shelters to stay during the photophase, avoiding exposure to diurnal predators. In this work, we first explored the interactions between individuals of the same or different species in the shelter selection process of Triatoma infestans (Klug 1834) and Rhodnius prolixus (Stål 1859). When two groups of insects (either of different nutritional status, nymphal instar or species) were released together over an experimental arena containing two identical shelters, all nymphs were distributed randomly, suggesting the absence of intra- and inters-pecific interactions. Secondly, we analysed their preferences for particular features of shelters by releasing one group of insects (either T. infestans or R. prolixus) over an arena containing two different refuges. Nymphs exhibited preferences for darker shelters with a vertical orientation of its substrate and elevated from the ground, highlighting the importance of such features in a shelter selection context. We conclude that these species disregard the presence of other individuals but evaluate certain characteristics of the shelters to choose them. This information may contribute to understanding the colonization/recolonization dynamic processes of these Chagas disease vectors. 相似文献
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Claudia Crestini Alessandro D'Annibale Giovanni Giovannozzi-Sermanni 《Biotechnology Techniques》1996,10(4):243-248
Summary Total and specific activities of extra-cellular laccases from Lentinus edodes were enhanced by adding corn straw and chestnut juice to the liquid growth medium. The aqueous extracts were chemically characterized and revealed the presence of several phenolic and non-phenolic compounds. Extensive extraction of these components from the tested extracts completely annulled their stimulating properties on laccase production, suggesting that these compounds can act at micromole levels. 相似文献
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This article presents for the first time a modified protocol for RNase protection analysis that allows the substitution of32P with33P without loss of the high sensitivity of this method achieved with32P. With this protocol, we were able to detect at least 1 pg of specific mRNA. In the RNase protection analysis33P labeled riboprobes are more advantageous with regard to an easier handling and better resolution. 相似文献
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Maurizio Meta Marco Ponte Marina Guastella Claudia Semino Gabriella Pietra Giovanni Battista Ratto Giovanni Melioli 《Cancer immunology, immunotherapy : CII》1995,40(4):235-240
Despite the combined use of surgery and chemoradiotherapy, the poor prognosis of advanced non-smallcell lung cancer (NSCLC) requires the definition of new therapeutic approaches. The presence of T lymphocytes, with peculiar phenotypic, functional and molecular characteristics within the tumour, suggested the possible use of these cells, expanded in vitro, in protocols of adoptive immunotherapy. We have described how a population of oligoclonal T lymphocytes, derived from advanced NSCLC, can be expanded in vitro and has the capability of lysing autologous cancer cells. What is more important, we observed that patients with advanced NSCLC, treated with TIL expanded in vitro and recombinant interleukin-2, seemed to have a disease-free period longer than that of patients treated with conventional chemoradiotherapy. in an attempt to find new sources of specific lymphocytes for immunotherapy, we describe the analysis of the phenotypic, functional and molecular characteristics of T lymphocytes, derived from lymph nodes draining advanced NSCLC. In this paper we show that these cells, have restriction patterns of T cell receptor chain similar to those detectable in the population of infiltrating T lymphocytes. This finding suggests that T cells derived from draining lymph nodes of advanced NSCLC have peculiar characteristics and can be a suitable source of effector cells for protocols of adoptive immunotherapy in lung cancer treatment. 相似文献
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