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991.
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993.
T. Žuna Pfeiffer S. Petrošanec I. Štolfa Čamagajevac F. Stević 《Plant biosystems》2018,152(5):1059-1066
Habitat fragmentation and modification have been recognized as the most serious threats to biodiversity. In Croatia, the intensive human activities resulted in the landscape transformation, reduction of grassland areas and loss of species number. Increasingly threatened are the wild edible and medicinal plants which contribute remarkably to the biodiversity of different grassland types. In northeastern Croatia, one of the last remnants of the steppe-like grassland remained preserved in a very complex anthropogenic landscape. We examined the diversity of vascular plants occurring on this small habitat patch. Among the relatively high number of plant taxa (in a total of 177) found during the two years of investigations, most could be used both for human nutrition (28 taxa), and for the treatment of a wide range of diseases (60 taxa), while some taxa have nutritional value for livestock (17 taxa). All 23 recorded taxa with edible and medicinal properties are threatened in Croatia, 21 are threatened across Europe, and two are Red Listed taxa. Our results showed that small and isolated steppe-like grassland represents an important refuge for variety of valuable plant species in intensively used landscapes. Accordingly, such small habitats should be, at least locally, effectively protected. 相似文献
994.
Stanislav Filip Jaroslav Mokrý Jiřina Vávrová Zuzana Šinkorová Stanislav Mičuda Pavel Šponer Alžběta Filipová Hana Hrebíková Govindan Dayanithi 《Journal of cellular and molecular medicine》2014,18(5):832-843
Bone marrow–derived cells represent a heterogeneous cell population containing haematopoietic stem and progenitor cells. These cells have been identified as potential candidates for use in cell therapy for the regeneration of damaged tissues caused by trauma, degenerative diseases, ischaemia and inflammation or cancer treatment. In our study, we examined a model using whole-body irradiation and the transplantation of bone marrow (BM) or haematopoietic stem cells (HSCs) to study the repair of haematopoiesis, extramedullary haematopoiesis and the migration of green fluorescent protein (GFP+) transplanted cells into non-haematopoietic tissues. We investigated the repair of damage to the BM, peripheral blood, spleen and thymus and assessed the ability of this treatment to induce the entry of BM cells or GFP+lin−Sca-1+ cells into non-haematopoietic tissues. The transplantation of BM cells or GFP+lin−Sca-1+ cells from GFP transgenic mice successfully repopulated haematopoiesis and the haematopoietic niche in haematopoietic tissues, specifically the BM, spleen and thymus. The transplanted GFP+ cells also entered the gastrointestinal tract (GIT) following whole-body irradiation. Our results demonstrate that whole-body irradiation does not significantly alter the integrity of tissues such as those in the small intestine and liver. Whole-body irradiation also induced myeloablation and chimerism in tissues, and induced the entry of transplanted cells into the small intestine and liver. This result demonstrates that grafted BM cells or GFP+lin−Sca-1+ cells are not transient in the GIT. Thus, these transplanted cells could be used for the long-term treatment of various pathologies or as a one-time treatment option if myeloablation-induced chimerism alone is not sufficient to induce the entry of transplanted cells into non-haematopoietic tissues. 相似文献
995.
P. Pazdiora I. Morávková T. Bergerová V. Štruncová P. Křížová M. Musílek Č. Beneš 《Folia microbiologica》2013,58(2):123-126
From 1993 to 2009, there was only one cluster of invasive meningococcal disease (IMD) reported in a community of children in the Czech Republic. This exceptional cluster that occurred in a preschool facility is the focus of this report. In response to the announcement of the disease, anti-epidemic precautions were put in place. Neisseria meningitidis isolates were delivered from local laboratories to the National Reference Laboratory for Meningococcal Infections in Prague. Phenotyping was performed there along with multilocus sequence typing. Related factors and microbiological results were analyzed retrospectively. In October 2009, three girls contracted IMD within a period of 1 week in a 42-member group in a preschool facility attached to the elementary school in Starý Plzenec-Sedlec. In relation to three cases of the disease, another 66 people were registered of which 58 underwent a microbiological examination. N. meningitidis was detected in a total of five (8.6 %) people. The National Reference Laboratory for Meningococcal Infections defined the type of the strain to be C: P1.18-1,34-2,38: F1-7: ST-467 (cc269) and penA27. Tests showed the precise identity of all strains obtained from the three sick children and of two strains contracted through contact with the preschool facility. Despite the complete recovery of all patients with no permanent damage, the need for rapid cooperation between clinical sites, diagnostic laboratories, and epidemiologists was confirmed. 相似文献
996.
997.
Dušan Ušjak Miroslav Dinić Katarina Novović Branka Ivković Nenad Filipović Magdalena Stevanović Marina T. Milenković 《化学与生物多样性》2021,18(1):e2000786
An increasing lack of available therapeutic options against Acinetobacter baumannii urged researchers to seek alternative ways to fight this extremely resistant nosocomial pathogen. Targeting its virulence appears to be a promising strategy, as it offers considerably reduced selection of resistant mutants. In this study, we tested antibiofilm potential of four synthetic chalcone derivatives against A. baumannii. Compound that showed the greatest activity was selected for further evaluation of its antivirulence properties. Real-time PCR was used to evaluate mRNA expression of biofilm-associated virulence factor genes (ompA, bap, abaI) in treated A. baumannii strains. Also, we examined virulence properties related to the expression of these genes, such as fibronectin- and collagen-mediated adhesion, surface motility, and quorum-sensing activity. The results revealed that the expression of all tested genes is downregulated together with the reduction of adhesion and motility. The conclusion is that 2′-hydroxy-2-methoxychalcone exhibits antivirulence activity against A. baumannii by inhibiting the expression of ompA and bap genes, which is reflected in reduced biofilm formation, adhesion, and surface motility. 相似文献
998.
Anže Žerdoner Čalasan Juliane Kretschmann Marc Gottschling 《Organisms Diversity & Evolution》2018,18(1):29-38
Tertiary endosymbiosis is proven through dinophytes, some of which (i.e. Kryptoperidiniaceae) have engulfed diatom algae containing a secondary plastid. Chloroplasts are usually inherited together permanently with the host cell, leading to co-phylogeny. We compiled a diatom sequence data matrix of two nuclear and two chloroplast loci. Almost all endosymbionts of Kryptoperidiniaceae found their closest relatives in free-living diatoms and not in other harboured algae, rejecting co-phylogeny and indicating that resident diatoms were taken up by dinophytes multiple times independently. Almost intact ultrastructure and insignificant genome reduction are supportive for young, if not recent events of diatom capture. With their selective specificity on the one hand and extraordinary degree of endosymbiotic flexibility on the other hand, dinophytes hosting diatoms share more traits with lichens or facultatively phototrophic ciliates than with green algae and land plants. Time estimates indicate the dinophyte lineages as consistently older than the hosted diatom lineages, thus also favouring a repeated uptake of endosymbionts. The complex ecological role of dinophytes employing a variety of organismic interactions may explain their high potential and plasticity in acquiring a great diversity of plastids. 相似文献
999.
Kovačević Milijana Jovanović Živko Andrejić Gordana Dželetović Željko Rakić Tamara 《Plant and Soil》2020,453(1-2):297-312
Plant and Soil - Phragmites australis grows as a pioneer plant species in several mine and flotation tailings ponds distinguished by extremely high concentrations of metals. The main goals of this... 相似文献
1000.
L. v. Vukotinović 《Plant Systematics and Evolution》1888,38(3):82-83
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