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991.
Single visit endodontics offers many advantages over multi visit treatment. Therefore, it is of interest to assess the preference of single visit over multiple visit root canals. We used 86,000 patient records and selected 9017 records matching the inclusion criteria for the analysis using statistical tools (Chi square test at p value <0.05). Data shows that people between 26 to 45 years are often affected with dental caries. Available data is biased towards multi visits rather than single visit regardless number of canals. 相似文献
992.
Peter Mueller Hai T. Do Christian Smit Christoph Reisdorff Kai Jensen Stefanie Nolte 《Oikos》2021,130(3):431-439
Tidal wetlands worldwide are undergoing rapid invasions by tall-growing clonal grasses. Prominent examples are invasions by species of the genera Spartina, Phragmites and Elymus. The responsible physiological and ecological drivers of these invasions are poorly understood. Physiological integration (PI) is a key trait of clonal plants, which enables the exchange of resources among ramets. We investigated PI in Elymus athericus, which has been rapidly spreading from high-marsh into low-marsh environments of European salt marshes during the last decades. We applied a nitrogen stable-isotope approach to trace nutrient translocation between ramets in a factorial mesocosm experiment. The experiment was set up to mimic an invasion pattern commonly found in tidal wetlands, i.e. from high-elevated and rarely flooded into low-elevated and frequently flooded microenvironments. We tested for intraspecific variability in PI by including two genotypes of Elymus that naturally occur at different elevations within the tidal frame, a high-marsh (HM) and a low-marsh (LM) genotype. PI strongly increased offspring ramet aboveground and belowground biomass by 62 and 81%, respectively. Offspring ramets under drained conditions had 95% greater belowground biomass than those under flooded conditions. LM genotype offspring ramets produced 27% more aboveground biomass than HM genotypes. Offspring ramets were clearly more enriched in 15N under flooded versus drained conditions; however, this positive effect of flooding on δ15N was only significant in the LM genotype. Our findings demonstrate the importance of PI for the growth of Elymus offspring ramets and thereby for the species' capacity for fast vegetative spread. We show that offspring ramets under stressful flooded conditions are more dependent on nutrient supply from parent ramets than those under drained conditions. Our data furthermore suggest a higher degree of adaptation to flooding via PI in the LM versus HM genotype. In conclusion, we highlight the importance of assessing PI and intraspecific trait variability to understand invasion processes within ecosystems. 相似文献
993.
Tung Hoang Thanh Thuong Tran Thi Cuong Do Manh Luan Vu Quoc Hien Vu Thi Hieu Tran Nam Nguyen Ba Phuong Hoang Thi Nhu Van The Vinh Bui Khai Hoang Dac Nhut Duong Tan 《Plant Cell, Tissue and Organ Culture》2021,145(2):393-403
Plant Cell, Tissue and Organ Culture (PCTOC) - One of the common problems in strawberry (Fragaria?×?ananassa) micropropagation is the vitrification phenomenon (succulent plantlets,... 相似文献
994.
Manh Cuong Do Cong Du Phan Tung Hoang Thanh Ngan Ha Thi My Luan Vu Quoc Phong Truong Hoai Khai Hoang Dac Phuong Truong Thi Bich Nhut Duong Tan 《Plant Cell, Tissue and Organ Culture》2021,146(3):577-588
Plant Cell, Tissue and Organ Culture (PCTOC) - Effects of silver nanoparticles (AgNPs) on somatic embryogenesis and plantlets with rhizome of Panax vietnamensis were presented in this study. The... 相似文献
995.
996.
Mi Sung Park Beom Kyung Kim Jae Yoeun Cheong Dong Joon Kim Jun Yong Park Do Young Kim Sang Hoon Ahn Kwang-Hyub Han Chae Yoon Chon Seung Up Kim 《PloS one》2013,8(2)
Background and Aims
The FibroTest (FT) demonstrated excellent diagnostic performance in the prediction of liver fibrosis in patients with chronic hepatitis B (CHB). Here, we aimed to identify predictors of discordance between FT and liver biopsy (LB) in Asian patients with CHB.Methods
Consecutive patients with CHB who underwent both LB and FT on the same day between 2007 and 2010 were recruited from three medical institutes. Laboratory evaluations including specific parameters for calculating FT score, such as α2-macroglobulin, apolipoprotein A1, haptoglobin, γ-glutamyl transpeptidase, and total bilirubin levels, were obtained. The Batts and Ludwig scoring system was used for histological analysis.Results
A total of 330 patients (200 male and 130 female) were analyzed. Discordances of at least two fibrosis stages between FT and LB were observed in 30 (9.1%) patients; using FT, fibrosis was underestimated in 25 patients and overestimated in 5 patients with reference to LB. Patients with discordance had a higher proportion of F3–4 (P<0.001) and F4 (P = 0.012) compared with those with nondiscordance. The discordance rate was significantly higher in those with F3–4 than those with F1–2 (15.4% vs. 3.0%, P<0.001). Multivariate analysis demonstrated F3–4 at LB as the only independent factor for discordance (P<0.001; odds ratio 5.95). After adjusting fibrosis stages, neither necroinflammatory activity on histology nor serum ALT level influenced FT values independently.Conclusion
Advanced fibrosis stage (F3–4) is the sole factor of discordance between FT and LB in Asian patients with CHB. 相似文献997.
Joseph A. Fraietta Yvonne M. Mueller Guibin Yang Alina C. Boesteanu Donald T. Gracias Duc H. Do Jennifer L. Hope Noshin Kathuria Shannon E. McGettigan Mark G. Lewis Luis D. Giavedoni Jeffrey M. Jacobson Peter D. Katsikis 《PLoS pathogens》2013,9(10)
The role of Type I interferon (IFN) during pathogenic HIV and SIV infections remains unclear, with conflicting observations suggesting protective versus immunopathological effects. We therefore examined the effect of IFNα/β on T cell death and viremia in HIV infection. Ex vivo analysis of eight pro- and anti-apoptotic molecules in chronic HIV-1 infection revealed that pro-apoptotic Bak was increased in CD4+ T cells and correlated directly with sensitivity to CD95/Fas-mediated apoptosis and inversely with CD4+ T cell counts. Apoptosis sensitivity and Bak expression were primarily increased in effector memory T cells. Knockdown of Bak by RNA interference inhibited CD95/Fas-induced death of T cells from HIV-1-infected individuals. In HIV-1-infected patients, IFNα-stimulated gene expression correlated positively with ex vivo T cell Bak levels, CD95/Fas-mediated apoptosis and viremia and negatively with CD4+ T cell counts. In vitro IFNα/β stimulation enhanced Bak expression, CD95/Fas expression and CD95/Fas-mediated apoptosis in healthy donor T cells and induced death of HIV-specific CD8+ T cells from HIV-1-infected patients. HIV-1 in vitro sensitized T cells to CD95/Fas-induced apoptosis and this was Toll-like receptor (TLR)7/9- and Type I IFN-dependent. This sensitization by HIV-1 was due to an indirect effect on T cells, as it occurred in peripheral blood mononuclear cell cultures but not purified CD4+ T cells. Finally, peak IFNα levels and viral loads correlated negatively during acute SIV infection suggesting a potential antiviral effect, but positively during chronic SIV infection indicating that either the virus drives IFNα production or IFNα may facilitate loss of viral control. The above findings indicate stage-specific opposing effects of Type I IFNs during HIV-1 infection and suggest a novel mechanism by which these cytokines contribute to T cell depletion, dysregulation of cellular immunity and disease progression. 相似文献
998.
Tijen Önkol Deniz S. Doğruer Leyla Uzun Selcen Adak Semiha Özkan M. Fethi Şahin 《Journal of enzyme inhibition and medicinal chemistry》2013,28(2):277-284
In this study, new 3-[(1(2H)-phthalazinone-2-yl(methyl/ethyl]-4-aryl-1,2,4-triazole-5-thione and 2-[[1(2H)-phthalazinone-2-yl]methyl/ethyl]-5-arylamino-1,3,4-thiadiazole derivatives were synthesized. Antimicrobial properties of the title compounds were investigated against two Gram (+) bacteria (S. aureus, B. subtilis), two Gram ( ? ) bacteria (P. aeruginosa, E. coli) and two yeast-like fungi (C. albicans and C. parapsilosis) using the broth microdilution method. Generally the compounds were found to be active against B. subtilis and the fungi. Derivatives carrying a 1,3,4-thiadiazole ring generally showed higher antimicrobial activity against B. subtilis and the fungi when compared to other synthesized compounds. 相似文献
999.
D. Phuong Do Daphne C. Watkins Martin Hiermeyer Brian K. Finch 《Economics & Human Biology》2013,11(1):30-41
While a growing literature has documented a link between neighborhood context and health outcomes, little is known about the relationship between neighborhood characteristics and height. Using individual data from the 1999-2004 U.S. National Health and Nutrition Examination Survey merged with tract-level data from the U.S. Census, we investigate several neighborhood characteristics, including neighborhood socioeconomic status (NSES), education index of concentration at the extremes (ICE), and population density, as potential predictors of height. Employing a series of two-level random intercept models, we find a one standard deviation increase in NSES to be associated with a 0.6–1.4 cm height advantage for white and foreign-born Mexican-American females and for U.S. born Mexican-American males, net of individual-level controls. Similarly, a 10 point increase in neighborhood education ICE was associated with 0.23–0.32 cm greater height for white and foreign-born Mexican-American females and U.S. born Mexican-American males. Population density was nominally negatively associated with height for foreign-born Mexican-American females. Our findings reveal that lower physical stature for some ethnic and gender groups is clustered within neighborhoods of low SES and education, suggesting that contextual factors may play a role in influencing height above individual-level attributes. 相似文献
1000.
In this paper, a non-uniform flexible tail of a fish robot was presented and the dynamic model was developed. In this model, the non-uniform flexible tail was modeled by a rotary slender beam. The hydrodynamics forces, including the reactive force and resistive force, were analyzed in order to derive the governing equation. This equation is a fourth-order in space and second-order in time Partial Differential Equation (PDE) of the lateral movement function. The coefficients of this PDE were not constants because of the non-uniform beams, so they were approximated by exponential functions in order to obtain an analytical solution. This solution describes the lateral movement of the flexible tail as a function of material, geometrical and actuator properties. Experiments were then carried out and compared to simulations. It was proved that the proposed model is suitable for predicting the real behavior of fish robots. 相似文献