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61.
Radiosensitivity and genetic complexity 总被引:2,自引:0,他引:2
M Terzi 《Journal of theoretical biology》1965,8(2):233-243
62.
Akif Evren Parlak Haluk Cakmak Suleyman Sandal Bayram Ylmaz Memet Sekerci Zuhal Karagz Genc Mehmet Tuzcu Mustafa Karatepe 《Journal of biochemical and molecular toxicology》2019,33(2)
In this study, the effects of the two Schiff base derivatives and their metal complexes were tested for MDA concentration, which is an indicator of lipid peroxidation, antioxidant vitamin A, vitamin E, and vitamin C levels in cell culture. A comparison was performed among the groups and it was observed that MDA, vitamin A, vitamin E, and vitamin C concentrations were statistically changed. According to the results, all compounds caused a significant oxidative stress without Zn complexes. Moreover, Mn(II), Cu(II), Zn(II), and Ni(II) complexes of Schiff bases derived from a condensation of 1,2‐bis (p‐aminophenoxy) ethane with naphthaldehydes and 4‐methoxy benzaldehyde were examined in terms of antitumor activity against MCF‐7 human breast cancer and L1210 murine leukemia cells. Furthermore, the derivatives were tested for antioxidative and prooxidative effects on MCF‐7 breast cancer cells. The compounds which were tested revealed that there was an antitumor activity for MCF‐7 and L 1210 cancer cells. Also, some of the compounds induced oxidative harmful. 相似文献
63.
Azeloglu EU Yun YH Saltman AE Krukenkamp IB Chiang FP Chen W Gaudette GR 《Journal of biomechanics》2006,39(4):717-725
The necessity to quantify the mechanical function with high spatial resolution stemmed from the advancement of myocardial salvaging techniques. Since these therapies are localized interventions, a whole field technique with high spatial resolution was needed to differentiate the normal, diseased, and treated myocardium. We developed a phase correlation algorithm for measuring myocardial displacement at high spatial resolution and to determine the regional mechanical function in the intact heart. Porcine hearts were exposed and high contrast microparticles were placed on the myocardium. A pressure transducer, inserted into the left ventricle, synchronized the pressure (LVP) with image acquisition using a charge-coupled device camera. The deformation of the myocardium was measured with a resolution of 0.58+/-0.04 mm. Within the region of interest (ROI), regional stroke work (RSW), defined as the integral of LVP with respect to regional area, was determined on average at 21 locations with a resolution of 27.1+/-2.7 mm2. To alter regional mechanical function, the heart was paced at three different locations around the ROI. Independent of the pacemaker location, RSW decreased in the ROI. In addition, a gradient of increasing RSW in the outward direction radiating from the pacemaker was observed in all pacing protocols. These data demonstrated the ability to determine regional whole field mechanical function with high spatial resolution, and the significant alterations induced by electrical pacing. 相似文献
64.
65.
This study investigated the effects of sociocultural contexts on health and the psychological well-being of immigrant adolescents, aged 15 to 18 years, originally from Bosnia and Herzegovina and now living as displaced persons either in Bosnia, or immigrants in Croatia and Austria. The study addresses the social determinants of health with a specific focus on five factors in the social environment that might have an influence on health status: gender, socio-economic status (SES), perceived discrimination and exposure to violence, social support and religious commitment. Dependent variables included self-rated health, a count of self-reported objective health problems and a range of indices of psychological well-being (somatic stress, anxiety, depression and self-esteem). The purpose of the study was to examine whether social risk factors have an effect on health, which factors mediate these effects on self-rated health and to assess whether these effects differ by gender Results indicate that perceived discrimination and violence are related to poor health through psychological stress as a major mechanism with stronger effects for girls in the study. Differences across the three socio-cultural contexts reveal the complexity and specificity of the relationships between analyzed factors as the association between discrimination and health was attenuated for some groups due to the protective resources of immigrants. 相似文献
66.
Photochemical efficiency of PSII of Ctenanthe setosa was investigated to understand the photosynthetic adaptation mechanism under drought stress causing leaf rolling. Stomatal
conductance (g
s), the levels of photosynthetic pigments and chlorophyll (Chl) fluorescence parameters were determined in leaves that had
four different visual leaf rolling scores from 1 to 4, opened after re-watering and mechanically opened at score 4. g
s value gradually decreased in adaxial and abaxial surfaces in relation to scores of leaf rolling. Pigment contents decreased
until score 3 but approached score 1 level at score 4. No significant variations in effective quantum yield of PSII (ΦPSII), and photochemical quenching (qp) were found until score 3, while they significantly decreased at score 4. Non-photochemical quenching (NPQ) increased at
score 2 but then decreased. After re-watering, the Chl fluorescence and other physiological parameters reached to approximately
score 1 value, again. As for mechanically opened leaves, g
s decreased during drought period. The decrease in adaxial surface was higher than that of the rolled leaves. NPQ was higher
than that of the rolled leaves. ΦPSII and qp significantly declined and the decreases were more than those of the rolled leaves. In conclusion, the results indicate that
leaf rolling protects PSII functionality from damage induced by drought stress. 相似文献
67.
Faik Ahmet Karavelioğulları Atilla Ocak Murat Ekici Evren Cabi 《Nordic Journal of Botany》2009,27(3):222-227
Verbascum eskisehirensis Karavel., Ocak & Ekici sp. nov. (sect. Bothrosperma Murb.) is described and illustrated from Turkey. This new species is confined to B3 Eskisehir in central Anatolia. A morphological comparison is made with the closely related species; V. oreophilum K. Koch and V. pyramidatum M. Bieb. In addition, a cluster analysis was conducted and a distribution map of the new species and the related species is also given. 相似文献
68.
Gill, trunk kidney, spleen, and liver of rainbow trout (Oncorhynchus mykiss) were examined after exposure to different sublethal concentrations of carbosulfan (25, 50 and 200 μg L−1), propineb (3, 6 and 24 mg L−1), and benomyl (2, 5 and 20 mg L−1) for 14 days. Lesions were observed in gill, trunk kidney, spleen, and liver of rainbow trout exposed to either concentration of pesticides. The most important lesions were determined in the highest concentrations of pesticides. Lamellar fusion, lamellar hyperplasia, epithelial lifting, vacuolization of epithelial tissue, epithelial necrosis, hypertrophy and sloughing of epithelium were observed on fish exposed to carbosulfan, propineb and benomyl. Fish had cell necrosis, degeneration and oedemas in liver, trunk kidney and spleen. None of these lesions were seen in control fish. 相似文献
69.
70.
Caglayan E Romeo GR Kappert K Odenthal M Südkamp M Body SC Shernan SK Hackbusch D Vantler M Kazlauskas A Rosenkranz S 《PloS one》2010,5(10):e13608