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排序方式: 共有85条查询结果,搜索用时 15 毫秒
31.
Ramajayam Govindan Venkatachalam Sivabalan Shazia Fathima JH Umaphathy Vidhya Rekha Senthilkumar Kalimuthu Selvaraj Jayaraman Kirubhanand Chandrasekaran 《Bioinformation》2020,16(11):937
The MUC1 oncoprotein is known to be linked with different types of cancer. Therefore, it is of interest to document the molecular docking analysis of compounds from Justica adhatoda L with the MUC1 oncoprotein. We report the structure based molecular binding features compounds such as amrinone, ethambutol, pyrazinamide and vasicoline the MUC1 oncoprotein for further consideration in drug discovery. 相似文献
32.
Erik JM Toonen Pilar Barrera Jaap Fransen Arjan PM de Brouwer Agnes M Eijsbouts Pierre Miossec Hubert Marotte Hans Scheffer Piet LCM van Riel Barbara Franke Marieke JH Coenen 《Arthritis research & therapy》2012,14(6):R264
Introduction
The goal of this study is to investigate whether the -308G > A promoter polymorphism in the tumor necrosis factor alpha (TNFA) gene is associated with disease severity and radiologic joint damage in a large cohort of patients with rheumatoid arthritis (RA).Methods
A long-term observational early RA inception cohort (n = 208) with detailed information about disease activity and radiologic damage after 3, 6 and 9 years of disease was genotyped for the TNFA -308G > A promoter polymorphism (rs1800629). A longitudinal regression analysis was performed to assess the effect of genotype on RA disease severity and joint damage. Subsequently, a meta-analysis, including all publically available data, was performed to further test the association between joint erosions and the TNFA polymorphism. To learn more about the mechanism behind the effect of the polymorphism, RNA isolated from peripheral blood from RA patients (n = 66) was used for TNFA gene expression analysis by quantitative PCR.Results
Longitudinal regression analysis with correction for gender and disease activity showed a significant difference in total joint damage between GG and GA+AA genotype groups (P = 0.002), which was stable over time. The meta-analysis, which included 2,053 patients, confirmed an association of the genetic variant with the development of erosions (odds ratio 0.78, 95% CI 0.62, 0.98). No significant differences in TNFA gene expression were observed for the different genotypes, confirming earlier findings in healthy individuals.Conclusions
Our data confirm that the TNFA -308G > A promoter polymorphism is associated with joint damage in patients with RA. This is not mediated by differences in TNFA gene expression between genotypes. 相似文献33.
Frank JH Gijsen Francesco Migliavacca Silvia Schievano Laura Socci Lorenza Petrini Attila Thury Jolanda J Wentzel Anton FW van der Steen Patrick WS Serruys Gabriele Dubini 《Biomedical engineering online》2008,7(1):23
Background
The process of restenosis after a stenting procedure is related to local biomechanical environment. Arterial wall stresses caused by the interaction of the stent with the vascular wall and possibly stress induced stent strut fracture are two important parameters. The knowledge of these parameters after stent deployment in a patient derived 3D reconstruction of a diseased coronary artery might give insights in the understanding of the process of restenosis. 相似文献34.
Chloroplast thylakoids contain three classes of glycolipids, monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG), and sulfoquinovosyldiacylglycerol (SQDG). We have investigated the stability of large unilamellar vesicles made from egg phosphatidylcholine (EPC) and different chloroplast glycolipids during freezing to -18 degreesC, as a function of the presence of three sugars: glucose, sucrose, or trehalose. Contrary to the situation in thylakoids, where cryoprotection increases from glucose < sucrose < trehalose, liposomes containing 50% DGDG showed the opposite behavior. In fact, carboxyfluorescein leakage increased over the control values (freezing in the absence of sugar) in the presence of trehalose. This effect was not seen in vesicles made from pure EPC, or a mixture of EPC and MGDG, or EPC and SQDG. Liposomes made from mixtures of all three glycolipids, however, showed even more leakage in the presence of trehalose than liposomes containing only DGDG and EPC. Copyright 1998 Academic Press. 相似文献
35.
36.
Lack of geographic variation in anonymous nuclear polymorphisms in the American oyster, Crassostrea virginica 总被引:1,自引:0,他引:1
Comparing geographic variation of noncoding nuclear DNA polymorphisms,
which presumably are neutral to natural selection, with geographic
variation of allozymes is potentially a good way to detect the effects of
selection on allozyme polymorphisms. A previous study of four anonymous
nuclear markers in the American oyster, Crassostrea virginica, found
dramatic differences in allele frequency between the Gulf of Mexico and the
Atlantic Ocean. In contrast, 14 allozyme polymorphisms were fairly uniform
in frequency between the two areas. This led to the conclusion that all of
the allozyme polymorphisms were kept uniform in frequency by balancing
selection. To test the robustness of this pattern, six additional anonymous
nuclear DNA polymorphisms were surveyed in oysters from Panacea, Fla, and
Charleston, S.C. on the Gulf and Atlantic coasts, respectively. Unlike the
previously studied DNA markers, the six DNA polymorphisms examined here
show geographic variation that is not significantly greater than that of
allozymes. The reason for the discrepancy between the two sets of DNA
polymorphisms is unclear.
相似文献
37.
Natural selection and the molecular clock 总被引:13,自引:1,他引:12
38.
Abstract. 1. This study explored interactions of two spatially and temporally separated weevils and their impact on Alliaria petiolata (garlic mustard) survival, growth, and reproduction at different herbivore densities.
2. The root-mining weevil Ceutorhynchus scrobicollis attacks A. petiolata rosettes from October to April, and larvae complete development in May. The shoot-mining weevil Ceutorhynchus alliariae attacks bolting plants in April/May with larvae completing development in June–July. Priority effects were expected, with early attack of C. scrobicollis affecting the later attacking C. alliariae , mediated through changes in plant growth or chemistry.
3. Attack by C. scrobicollis significantly increased plant mortality and changed plant architecture, while C. alliariae only significantly reduced plant height. Attack by C. scrobicollis also increased nitrogen content of stems.
4. Root feeding by C. scrobicollis affected the feeding niche of C. alliariae , but increased stem nitrogen content did not result in increased stem miner survival. While reduced height and stem diameters as a result of C. scrobicollis attack reduced C. alliariae attack at the stem level, attack at plant level and recruitment was unaffected.
5. Weevil density had no effect on plant performance, most likely due to strong intraspecific competition, and there were no synergistic effects between the two herbivores.
6. Overall, attack by C. scrobicollis was more detrimental to A. petiolata growth, seed output, and survival than attack by C. alliariae . Consequently, C. scrobicollis has been prioritised as a potential biocontrol agent for control of A. petiolata in North America. 相似文献
2. The root-mining weevil Ceutorhynchus scrobicollis attacks A. petiolata rosettes from October to April, and larvae complete development in May. The shoot-mining weevil Ceutorhynchus alliariae attacks bolting plants in April/May with larvae completing development in June–July. Priority effects were expected, with early attack of C. scrobicollis affecting the later attacking C. alliariae , mediated through changes in plant growth or chemistry.
3. Attack by C. scrobicollis significantly increased plant mortality and changed plant architecture, while C. alliariae only significantly reduced plant height. Attack by C. scrobicollis also increased nitrogen content of stems.
4. Root feeding by C. scrobicollis affected the feeding niche of C. alliariae , but increased stem nitrogen content did not result in increased stem miner survival. While reduced height and stem diameters as a result of C. scrobicollis attack reduced C. alliariae attack at the stem level, attack at plant level and recruitment was unaffected.
5. Weevil density had no effect on plant performance, most likely due to strong intraspecific competition, and there were no synergistic effects between the two herbivores.
6. Overall, attack by C. scrobicollis was more detrimental to A. petiolata growth, seed output, and survival than attack by C. alliariae . Consequently, C. scrobicollis has been prioritised as a potential biocontrol agent for control of A. petiolata in North America. 相似文献
39.
E. N. JACK BROOKSHIRE STEFAN GERBER JACKSON R. WEBSTER JAMES M. VOSE WAYNE T. SWANK 《Global Change Biology》2011,17(1):297-308
The microbial conversion of organic nitrogen (N) to plant available forms is a critical determinant of plant growth and carbon sequestration in forests worldwide. In temperate zones, microbial activity is coupled to variations in temperature, yet at the ecosystem level, microbial N mineralization seems to play a minor role in determining patterns of N loss. Rather, N losses often appear to vary with seasonality in hydrology and plant demand, while exports over longer periods are thought to be associated with increasing rates of anthropogenic N deposition. We analyzed long‐term (21–32 years) time series of climate and stream and atmospheric chemistry from two temperate deciduous forest watersheds in the southeastern USA to understand the sensitivity of internal forest N cycles to climate variation and atmospheric deposition. We evaluated the time series with a simple analytical model that incorporates key biotic constraints and mechanisms of N limitation and cycling in plant–soil systems. Through maximum likelihood analysis, we derive biologically realistic estimates of N mineralization and its temperature sensitivity (Q10). We find that seasonality and long‐term trends in stream nitrate (NO3) concentrations can in large part be explained by the dynamics of internal biological cycling responding to climate rather than external forcing from atmospheric chemistry. In particular, our model analysis suggests that much of the variation in N cycling in these forests results from the response of microbial activity to temperature, causing NO3 losses to peak in the growing season and to accelerate with recent warming. Extrapolation of current trends in temperature and N deposition suggests that the upturn in temperature may increase future N export by greater than threefold more than from increasing deposition, revealing a potential direct effect of anthropogenic warming on terrestrial N cycles. 相似文献
40.
Christie M Bartels Jessica M Saucier Carolyn T Thorpe Amy JH Kind Nancy Pandhi Karen E Hansen Maureen A Smith 《Arthritis research & therapy》2012,14(4):R166