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61.
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Epidermal studies in fifteen Indian cultivars of Bougainvilleas are described. The epidermal cells are polygonal isodiametric, or elongated with thick straight arched or slightly sinuous walls. Parallel culticular striations are radiating from guard cells. The mature stomata are anomocytic, paracytic and with a single subsidiary cell. The abnormal types noticed are: single guard cells with or without pores, arrested development, variously oriented contiguous stomata, cytoplasmic connections between nearby stomata and epidermal or subsidiary cells, and persistent stomatal cells. The development of anomocytic stomata is perigenous while that of the other types is mesogenous. Fifteen cultivars of Bougainvilleas are separated on the basis of bract colour, stomatal frequency and index per unit area.  相似文献   
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Gold nanoparticles (GNPs) are claimed as outstanding biomedical tools for cancer diagnostics and photo-thermal therapy, but without enough evidence on their potentially adverse immunological effects. Using a model of human dendritic cells (DCs), we showed that 10 nm- and 50 nm-sized GNPs (GNP10 and GNP50, respectively) were internalized predominantly via dynamin-dependent mechanisms, and they both impaired LPS-induced maturation and allostimulatory capacity of DCs, although the effect of GNP10 was more prominent. However, GNP10 inhibited LPS-induced production of IL-12p70 by DCs, and potentiated their Th2 polarization capacity, while GNP50 promoted Th17 polarization. Such effects of GNP10 correlated with a stronger inhibition of LPS-induced changes in Ca2+ oscillations, their higher number per DC, and more frequent extra-endosomal localization, as judged by live-cell imaging, proton, and electron microscopy, respectively. Even when released from heat-killed necrotic HEp-2 cells, GNP10 inhibited the necrotic tumor cell-induced maturation and functions of DCs, potentiated their Th2/Th17 polarization capacity, and thus, impaired the DCs'' capacity to induce T cell-mediated anti-tumor cytotoxicity in vitro. Therefore, GNP10 could potentially induce more adverse DC-mediated immunological effects, compared to GNP50.  相似文献   
65.
Industrial wastewaters polluted with toxic heavy metals are serious ecological and environmental problem. Therefore, in this study multi-heavy metals (Fe2+, Cu2+, Ni2+ and Zn2+) removal process with mixed microbial culture was examined in the horizontal rotating tubular bioreactor (HRTB) by different combinations of process parameters. Hydrodynamic conditions and biomass sorption capacity have main impact on the removal efficiency of heavy metals: Fe2+ 95.5–79.0%, Ni2+ 92.7–54.8%, Cu2+ 87.7–54.9% and Zn2+ 81.8–38.1%, respectively. On the basis of experimental results, integral mathematical model of removal heavy metals in the HRTB was established. It combines hydrodynamics (mixing), mass transfer and kinetics to define bioprocess conduction in the HRTB. Mixing in the HRTB was described by structured cascade model and metal ion removal by two combined diffusion–adsorption models, respectively. For Langmuir model, average variances between experimental and simulated concentrations of metal ions were in the range of 1.22–10.99 × 10−3 and for the Freundlich model 0.12–3.98 × 10−3, respectively. On the basis of previous facts, it is clear that developed integral bioprocess model with Freundlich model is more efficient in the prediction of concentration of metal ions in the HRTB. Furthermore, the results obtained also pointed out that the established model is at the same time accurate and robust and therefore it has great potential for use in the scale-up procedure.  相似文献   
66.
The case reports come from the files of the State Department of Public Health which, together with the California Medical Association, now sponsors the statewide studies of all maternal mortalities. Selected Cases are to be presented here from time to time as a matter of interest and illumination to all physicians concerned with the practice of obstetrics. It is hoped that a review of such significant cases will help to improve the welfare of future California mothers.  相似文献   
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70.
Sensitivity and correlations among three endpoints were evaluated to assess the genotoxic potential of organic complex mixtures in vitro. This study was focused on DNA adduct formation, DNA single strand break induction and tumour suppressor p53 protein up-regulation produced by extractable organic matter (EOM) absorbed on respirable particulate matter PM10 (particulate matter < 10 μm) collected in three European cities (Prague, Sofia, Košice) during winter and summer period. To compare the sensitivity of particular endpoints for in vitro measurement of complex mixture genotoxicity, the metabolically competent human hepatoma cell line Hep G2 was treated with equivalent EOM concentration of 50 μg/ml. Cell exposure to EOMs resulted in significant DNA adduct formation and DNA strand break induction, however, a lack of protein p53 up-regulation over the steady-state level was found. While the maximum of DNA strand breaks was determined after 2 h cell exposure to EOMs, 24 h treatment interval was optimal for DNA adduct determination.

No substantial location- and season-related differences in EOM genotoxicity were detected using DNA strand break assessment. In agreement with these results no significant variation in DNA adduct levels were found in relation to the locality and season except for the monitoring site in Prague. The Prague EOM sample collected during summer period produced nearly three-fold lower DNA adduct level in comparison to the winter EOM sample.

Comparable results were obtained when the ambient air genotoxicity, based on the concentration of carcinogenic PAHs in cubic meter of air (ng c-PAHs/m3), was elicited using either DNA adduct or strand break determination. In general, at least six-fold higher genotoxicity of the winter air in comparison to the summer air was estimated by each particular endpoint. Moreover, the genotoxic potential of winter air revealed by DNA adduct assessment and DNA strand break measurement increased in the same order: Košice  Prague < Sofia.

Based on these data we suppose that two endpoints DNA breakage and DNA adduction are sensitive in vitro biomarkers for estimation of genotoxic activity of organic complex mixture associated with airborne particles. On the other hand, the measurement of protein p53 up-regulation manifested some limitations; therefore it cannot be used as a reliable endpoint for in vitro genotoxicity assessment.  相似文献   

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