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排序方式: 共有114条查询结果,搜索用时 15 毫秒
41.
Abstract This paper presents data on indoor air quality in schools as perceived by those working in them and relates these data to exposure measurements. Data on subjective air quality, domestic exposures and health aspects were gathered by means of a questionnaire which was sent to all personnel in 38 schools; it was completed by 1410 persons (85’4 of the total). Data on exposure were gathered by exposure measurements in classrooms. The results indicate that 53% of the personnel perceived the indoor air quality as bad or very bad. It was perceived as worse by those who were younger, those who were dissatisfied with their psychosocial work climate and those who were not exposed to tobacco smoke at home. In older school buildings and buildings with displacement ventilation there was less dissatisfaction with the air quality. There were no significant relations between complaints and air exchange rate or concentration of carbon dioxide. The air quality was perceived as worse at higher levels of exposure to a number of airborne compounds including volatile organic compounds, moulds, bacteria and respirable dust. It was concluded that exposure to indoor pollutants affects perception even at the low concentrations normally found indoors in nonindustrial buildings. 相似文献
42.
Pistolozzi M Varchi G Degli Esposti A Guerrini A Sotgiu G Ballestri M Ferroni C Venturini A Bertucci C 《ChemMedChem》2011,6(9):1706-1714
Adverse effects have limited the clinical potential of 20‐(S)‐camptothecin (CPT) and led to a growing interest in the development of CPT analogues that exhibit less severe drawbacks, while maintaining their therapeutic activity. Recently, a thiopyridone isostere of CPT, 20‐(S)‐thiocamptothecin (TCPT), was developed that resulted more potent than the parent compound in H460, HT29 and IGROV‐1 cell lines. The improved activity of TCPT over CPT might be due to the greater stability of the lactone ring. Here, reversible hydrolysis to the ring‐open carboxylate forms of CPT and TCPT was studied by HPLC, both in the presence and absence of human serum albumin (HSA). The amount of TCPT that exists in the lactone form at equilibrium in buffer solution (24 h) was found to be significantly higher than CPT, and the same trend was observed in the presence of HSA. Specifically, HSA caused a shift in the hydrolysis equilibrium of TCPT towards the carboxylate form, but the proportion of lactone form remained higher than that observed for CPT under the same conditions, and also in the presence of a higher excess of the protein. The role of the sulfur atom in the stability of the open and closed lactone derivatives was investigated by theoretical calculations using stabilization energies and comparison between experimental and calculated absorption spectra. Our results suggest that, in aqueous solution, more ionic species (anionic and enolic forms) are present for TCPT. This study provides further insights into the effects of oxygen/sulfur replacement in the CPT pyridone ring. 相似文献
43.
ZQ Hu JL Liu HP Li S Xing S Xue JB Zhang JH Wang G Nölke YC Liao 《International journal of molecular sciences》2012,13(6):7038-7056
Fusarium verticillioides is the primary causal agent of Fusarium ear and kernel rot in maize, producing fumonisin mycotoxins that are toxic to humans and domestic animals. Rapid detection and monitoring of fumonisin-producing fungi are pivotally important for the prevention of mycotoxins from entering into food/feed products. Chicken-derived single-chain variable fragments (scFvs) against cell wall-bound proteins from F. verticillioides were isolated from an immunocompetent phage display library. Comparative phage enzyme-linked immunosorbant assays (ELISAs) and sequencing analyses identified four different scFv antibodies with high sensitivity. Soluble antibody ELISAs identified two highly sensitive scFv antibodies, FvCA3 and FvCA4, with the latter being slightly more sensitive. Three-dimensional modeling revealed that the FvCA4 may hold a better overall structure with CDRH3, CDRL1 and CDRL3 centered in the core region of antibody surface compared with that of other scFvs. Immunofluorescence labeling revealed that the binding of FvCA4 antibody was localized to the cell walls of conidiospores and hyphae of F. verticillioides, confirming the specificity of this antibody for a surface target. This scFv antibody was able to detect the fungal mycelium as low as 10(-2) μg/mL and contaminating mycelium at a quantity of 10(-2) mg/g maize. This is the first report that scFv antibodies derived from phage display have a wide application for rapid and accurate detection and monitoring of fumonisin-producing pathogens in agricultural samples. 相似文献
44.
Albina Fejza Maurizio Polano Lucrezia Camicia Evelina Poletto Greta Carobolante Giuseppe Toffoli Maurizio Mongiat Eva Andreuzzi 《International journal of molecular sciences》2021,22(14)
The use of immune checkpoint inhibitors has revolutionized the treatment of melanoma patients, leading to remarkable improvements in the cure. However, to ensure a safe and effective treatment, there is the need to develop markers to identify the patients that would most likely respond to the therapies. The microenvironment is gaining attention in this context, since it can regulate both the immunotherapy efficacyand angiogenesis, which is known to be affected by treatment. Here, we investigated the putative role of the ECM molecule EMILIN-2, a tumor suppressive and pro-angiogenic molecule. We verified that the EMILIN2 expression is variable among melanoma patients and is associated with the response to PD-L1 inhibitors. Consistently, in preclinical settings, the absence of EMILIN-2 is associated with higher PD-L1 expression and increased immunotherapy efficacy. We verified that EMILIN-2 modulates PD-L1 expression in melanoma cells through indirect immune-dependent mechanisms. Notably, upon PD-L1 blockage, Emilin2−/− mice displayed improved intra-tumoral vessel normalization and decreased tumor hypoxia. Finally, we provide evidence indicating that the inclusion of EMILIN2 in a number of gene expression signatures improves their predictive potential, a further indication that the analysis of this molecule may be key for the development of new markers to predict immunotherapy efficacy. 相似文献
45.
Greta Forlani Mariam Shallak Roberto Sergio Accolla Maria Grazia Romanelli 《International journal of molecular sciences》2021,22(15)
Since the discovery of the human T-cell leukemia virus-1 (HTLV-1), cellular and animal models have provided invaluable contributions in the knowledge of viral infection, transmission and progression of HTLV-associated diseases. HTLV-1 is the causative agent of the aggressive adult T-cell leukemia/lymphoma and inflammatory diseases such as the HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). Cell models contribute to defining the role of HTLV proteins, as well as the mechanisms of cell-to-cell transmission of the virus. Otherwise, selected and engineered animal models are currently applied to recapitulate in vivo the HTLV-1 associated pathogenesis and to verify the effectiveness of viral therapy and host immune response. Here we review the current cell models for studying virus–host interaction, cellular restriction factors and cell pathway deregulation mediated by HTLV products. We recapitulate the most effective animal models applied to investigate the pathogenesis of HTLV-1-associated diseases such as transgenic and humanized mice, rabbit and monkey models. Finally, we summarize the studies on STLV and BLV, two closely related HTLV-1 viruses in animals. The most recent anticancer and HAM/TSP therapies are also discussed in view of the most reliable experimental models that may accelerate the translation from the experimental findings to effective therapies in infected patients. 相似文献
46.
47.
Greta Schuler 《Urban Forum》2017,28(1):27-42
Existing evidence indicates that cross-border migrant women sex workers in South Africa are often marginalized by state and non-state actors professing to assist them. Trafficking discourses frequently conflate migrant sex workers with trafficking victims, denying them agency and silencing the women under discussion. This paper emphasizes the voices of the women themselves, drawing from the first academic research employing creative writing workshops as a methodology with migrant women sex workers in Johannesburg, South Africa. This work responds to calls for more innovative methodologies to reach marginalized or “invisible” groups and adds to the “voices” of urban poor migrants to provide more information about the lived experiences of migrant sex workers in Johannesburg. Narratives from five Zimbabwean sex workers in Johannesburg reveal representations of sex work that are paradoxically both “good” and “bad”—ambiguous in a way the polarized discussions around sex work rarely reflect and in a way that might be best expressed through creative writing. In a country increasingly concerned with issues of (anti-)immigration and (anti-)trafficking, these women are often positioned as vulnerable and misidentified as trafficked; however, their self-representations portrayed complex women calculating and making decisions, especially related to their health and safely. This paper concentrates on letters the participants wrote to young sex workers, which highlight the participatory aspect of this method and show the complexities an arts-based method can reveal. 相似文献
48.
Greta Motiekaityte Aukse Navaruckiene Vita Raudoniene Danguole Bridziuviene Justinas Jaras Kristina Kantminiene Jolita Ostrauskaite 《应用聚合物科学杂志》2023,140(2):e53289
Considering the current efforts for to develop new antimicrobial polymers from renewable resources suitable for application in environmentally friendly light-based technologies, novel dual-cured photopolymers of vanillin alcohol diglycidyl ether and glycerol dimethacrylate are developed. The kinetics of the sequential and simultaneous dual-curing processes, combining free radical and cationic photopolymerizations, is investigated by real-time photorheometry. Comparison of dual-curing systems with different ratios of biobased epoxy and acrylate monomers revealed that the increase in the acrylate content increases the photocuring rate and improves the mechanical performance (Young's modulus increases from 76.64 to 190.71 MPa) and thermal stability (the 10% weight loss increases from 227 to 274°C) of the polymers, while the increase in the vanillin epoxy content results in better antimicrobial activity. Developed photopolymers create unfavorable conditions for the growth of microorganisms and reduce their population by up to 0% in 24 h. The excellent antibacterial and antifungal activity of new photopolymers allows them to be considered as biobased alternatives to petroleum-based antimicrobial coatings, films, or optical 3D printed objects. 相似文献
49.
Increasingly, researchers are becoming sensitive to the conceptual and methodological problems that arise when data are stripped from their historical and interpersonal contexts. Careful attention to the importance of grounding theory in participants' experiences can enhance all research, regardless of its underlying paradigm. This comment examines P. Suedfeld and S. Bluck's (see record 1993-21556-001) study on integrative complexity as a case in point to highlight the importance of taking context and phenomenological experience into account. In particular, 2 methodological considerations central to personal document analysis are discussed: (a) the role that intentions, relationships, and sociohistorical context play in shaping the content of personal documents and (b) the problems of classifying diverse human experiences without regard to their meaning for the people who lived through them. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
Scholnick Ellin K.; Fein Greta G.; Campbell Patricia F. 《Canadian Metallurgical Quarterly》1990,26(2):188
Differential predictors of route map use in wayfinding by 48 48–63-month-olds vs 46 64–79-month-olds were tested. Predictors of map use should shift from landmark to array encoding, from mental rotation of 1 element to array rotation, and from direct perception of an array to recall. Landmark and array encoding and array rotation were measured by duplication of placements on an array when 2 arrays were aligned or 1 was rotated 180°. Matching a rotated letterlike form to a standard gauged single-element rotation; recall of landmark locations after their removal from an array indexed memory. Each rotation task and landmark placements predicted the younger children's map scores; array encoding, single-element rotation, and recall predicted older children's map errors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献