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941.
The results of a bioindication study based on the diversity of epiphytic lichens in a semi-arid area of South Italy are presented.
The area features the presence of an industrial zone located in a rural context. The survey was performed in 20 sampling sites.
The lichen diversity values (LDV) were determined by the frequencies of all lichen species within a sampling grid placed on
tree trunks. Lichens demonstrated a condition of environmental alteration extending to the industrial zone, and tending towards
a recovery in the rural surroundings. The survey also showed evidence of eutrophication all over the study area. 相似文献
942.
A M Da-Cruz D V Filgueiras Z Coutinho W Mayrink G Grimaldi P M De Luca S C Mendonca S G Coutinho 《Memórias do Instituto Oswaldo Cruz》1999,94(4):537-542
An atypical case of acquired immunodeficiency syndrome-associated mucocutaneous lesions due to Leishmania braziliensis is described. Many vacuolated macrophages laden with amastigote forms of the parasite were found in the lesions. Leishmanin skin test and serology for leishmaniasis were both negative. The patient was resistant to therapy with conventional drugs (antimonial and amphotericin B). Interestingly, remission of lesions was achieved after an alternative combined therapy of antimonial associated with immunotherapy (whole promastigote antigens). Peripheral blood mononuclear cells were separated and stimulated in vitro with Leishmania antigens to test the lymphoproliferative responses (LPR). Before the combined immunochemotherapy, the LPR to leishmanial antigens was negligible (stimulation index - SI=1.4). After the first course of combined therapy it became positive (SI=4.17). The antigen responding cells were predominantly T-cells (47.5%) most of them with CD8+ phenotype (33%). Very low CD4+ cells (2.2%) percentages were detected. The increased T-cell responsiveness to leishmanial antigens after combined therapy was accompanied by interferon-g (IFN-g) production as observed in the cell culture supernatants. In this patient, healing of the leishmaniasis lesions was associated with the induction of a specific T-cell immune response, characterized by the production of IFN-g and the predominance of the CD8+ phenotype among the Leishmania-reactive T-cells. 相似文献
943.
Giacomucci Antonio Baldo Gian Luca 《The International Journal of Life Cycle Assessment》1999,4(3):165-166
The International Journal of Life Cycle Assessment - 相似文献
944.
Ahmed Kassab Luca Sabatini Gidon Lieberman Amanda Tozer Ariel Zosmer Colin Davis Talha Al-Shawaf 《Reproductive biology and endocrinology : RB&E》2007,5(1):32-6
Background
The aim was to examine the correlation of early follicular serum lutinising hormone (LH) and the clinical outcome of assisted reproduction technique (ART). 相似文献945.
Chromosomal aberrations and micronuclei induced in rat and mouse bone marrow cells by sodium nitrate 总被引:1,自引:0,他引:1
The genotoxicity of several anthraquinone compounds metabolically related to aflatoxin B1 was examined by means of the hepatocyte primary culture (HPC)/DNA repair test and the Salmonella microsome mutagenesis test, and compared to versicolorins A and B which are potent mutagenic and genotoxic intermediates of the aflatoxin biosynthetic pathway. 6,8-O-Dimethyl-versicolorins A, B and 6-deoxyversicolorin A were found to be strongly mutagenic and genotoxic. Genotoxicity of versicolorin A and 6,8-O-dimethylversicolorin A was stronger than that of versicolorin B and 6,8-O-dimethylversicolorin B, respectively, in the HPC/DNA repair test. Nidurufin and norsolorinic acid, which do not possess a bisfuran ring, exhibited questionable activities for mutagenicity and no genotoxicity. It is suspected that 6,8-O-dimethylversicolorins A, B and 6-deoxyversicolorin A as well as versicolorins A and B are genotoxic carcinogens. 相似文献
946.
The Senescence Process in Oat Leaves and its Regulation by Oxygen Concentration and Light Irradiance
The regulation of senescence by oxygen-concentration, lightirradiance and H2O2 has been studied in leaf segments of Avenasativa L. cv. Suregrain. The development of the components of the senescence process,for example chlorophyll breakdown, proteolysis (as soluble aminoacids), hydroperoxides (as malondi-aldehyde) and permeability(as conductivity) is accelerated in light as the O2-tensionincreases. In darkness, 0.3% O2 accelerates increases in hydroperoxides,permeability and proteolysis and delays the chlorophyll break-down,but 0.0005% O2 delays all the components studied. In every casethe hydroperoxide content, permeability and proteolysis areclosely related. Any treatment inducing an increase in membranepermeability causes chlorophyll bleaching (photo-oxidation)if leaf segments are then treated with light in an atmospherecontaining oxygen. Light has a modulating effect on the senescenceprocess. An irradiance lower or higher than 40 W m2 hasan accelerating effect on the senescence process. (Received September 7, 1985; Accepted July 30, 1985) 相似文献
947.
948.
Raffaella Belvedere Valentina Bizzarro Luca Parente Francesco Petrella 《Cell Adhesion & Migration》2018,12(2):168-183
Prisma® Skin is a new pharmaceutical device developed by Mediolanum Farmaceutici S.p.a. It includes alginates, hyaluronic acid and mainly mesoglycan. The latter is a natural glycosaminoglycan preparation containing chondroitin sulfate, dermatan sulfate, heparan sulfate and heparin and it is used in the treatment of vascular disease. Glycosaminoglycans may contribute to the re-epithelialization in the skin wound healing, as components of the extracellular matrix. Here we describe, for the first time, the effects of Prisma® Skin in in vitro cultures of adult epidermal keratinocytes and dermal fibroblasts. Once confirmed the lack of cytotoxicity by mesoglycan and Prisma® Skin, we have shown the increase of S and G2 phases of fibroblasts cell cycle distribution. We further report the strong induction of cell migration rate and invasion capability on both cell lines, two key processes of wound repair. In support of these results, we found significant cytoskeletal reorganization, following the treatments with mesoglycan and Prisma® Skin, as confirmed by the formation of F-actin stress fibers. Additionally, together with a significant reduction of E-cadherin, keratinocytes showed an increase of CD44 expression and the translocation of ezrin to the plasma membrane, suggesting the involvement of CD44/ERM (ezrin-radixin-moesin) pathway in the induction of the analyzed processes. Furthermore, as showed by immunofluorescence assay, fibroblasts treated with mesoglycan and Prisma® Skin exhibited the increase of Fibroblast Activated Protein α and a remarkable change in shape and orientation, two common features of reactive stromal fibroblasts. In all experiments Prisma® Skin was slightly more potent than mesoglycan. In conclusion, based on these findings we suggest that Prisma® Skin may be able to accelerate the healing process in venous skin ulcers, principally enhancing re-epithelialization and granulation processes. 相似文献
949.
Targeting the phosphatidylinositol 3‐kinase/Akt/mechanistic target of rapamycin signaling pathway in B‐lineage acute lymphoblastic leukemia: An update 下载免费PDF全文
950.
Decellularized colorectal cancer matrix as bioactive microenvironment for in vitro 3D cancer research 下载免费PDF全文