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31.
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Molecular evolution of the RNA polymerase II CTD   总被引:1,自引:0,他引:1  
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Whole-body autoradiography demonstrated the different distribution of [125I]-C-ANP and [125I]-ANP to rat tissues. Highest enrichment of radioactivity of both labelled peptides was found in the kidney. In some organs we found remarkable differences between [125I]-ANP and [125I]-C-ANP. In the kidney cortex, especially in the glomeruli, as well as in the endocardium, the zona glomerulosa and the medulla of the adrenal gland, where high levels of radioactivity after [125I]-ANP administration were detected, no or just few radioactivity was found after administration of [125I]-C-ANP. On the other hand in the kidney papilla and the outer subcortical medulla, characteristic blackening was found after [125I]-C-ANP administration. Those differences might be important for the understanding of pharmacological actions of ANP analogues.  相似文献   
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The genetically controlled immune response to calf skin collagen type I in mice could be demonstrated to be governed by at least two genes. One is linked to theH-2 complex and located within theIA subregion. High-responder alleles areH-2 b ,H-2 f , andH-2 s . The other gene(s) is not linked to theH-2 complex and high-responder allele(s) are found in the genome of B10 mice but not in the genome of DBA mice. There are strong indications that theIr-1A gene controls the response at the T-cell level, whereas it is assumed that the background gene(s) control the immune response at a different level.  相似文献   
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The human TAR RNA-binding protein (hTRBP) and protein activator of protein kinase R (hPACT) are important players in RNA interference (RNAi). Together with hArgonaute2 (hAgo2) and hDicer they have been reported to form the RISC-loading complex (RLC). Among other functions, hTRBP was suggested to assist the loading of hAgo2 with small interfering RNAs (siRNAs) within the RLC. Although several studies have been conducted to evaluate the specific functions of hTRBP and hPACT in RNAi, exact mechanisms and modes of action are still unknown. Here, we present a biochemical study further evaluating the role of hTRBP and hPACT in hAgo2-loading. We found that both proteins enhance hAgo2-mediated RNA cleavage significantly; even a hAgo2 mutant impaired in siRNA binding shows full cleavage activity in the presence of hTRBP or hPACT. Pre-steady state binding studies reveal that the assembly of wildtype-hAgo2 (wt-hAgo2) and siRNAs remains largely unaffected, whereas the binding of mutant hAgo2-PAZ9 to siRNA is restored by adding either hTRBP or hPACT. We conclude that both proteins assist in positioning the siRNA within hAgo2 to ensure optimal binding and cleavage. Overall, our data indicate that hTRBP and hPACT are part of a regulative system of RNAi that is important for efficient target RNA cleavage.  相似文献   
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We compared the syntheses and turnovers of two proteins related to the polyoma small T antigen synthesized in Escherichia coli from plasmids containing polyoma genomic segments joined to lac control elements. A protein with an authentic polyoma N terminus was more unstable than a protein with N-terminal amino acids derived from beta-galactosidase. Both were more unstable than most bacterial proteins.  相似文献   
40.

Background

Random glucose is widely measured in epidemiological studies and in the clinical setting when standardized fasting protocols and oral glucose tolerance testing or HbA1c measuring are not feasible. The relationship between random glucose and all-cause mortality has hardly been studied so far and was examined in the present study.

Methods

We ascertained mortality status among 5955 persons aged 18–79?years and free of known diabetes when participating in the German National Health Interview and Examination Survey 1998 (mean observation time 11.7?years, 458 deaths). Cox regression was applied to analyze the association of random serum glucose with all-cause mortality taken potential confounders into account. Relative mortality risks were estimated as hazard ratios (HRs) with 95% confidence intervals (CIs) modeling random glucose as categorical or continuous variable.

Results

Compared to random glucose levels of 4.3 -?<?5.3?mmol/L, HRs (95% CIs) were 1.94 (0.85–4.45) for levels <?4.3?mmol/L and 1.16 (0.89–1.50), 1.20 (0.91–1.58), 1.42 (0.88–2.29), 2.02 (1.26–3.25) and 4.71 (2.20–10.10) for levels 5.3 -?<?5.8, 5.8 -?<?6.8, 6.8 -?<?7.8, 7.8 -?<?11.1 and?≥?11.1?mmol/L, adjusted for age, sex, lifestyle, anthropometry and chronic diseases. An additional adjustment for fasting time or HbA1c yielded similar estimates. Modeling continuous random glucose by restricted cubic spline functions revealed comparable findings.

Conclusions

In the present epidemiological study drawn from the general population, random glucose showed a significant association with all-cause mortality, independent of main potential confounders. Thus, random glucose measures are highly relevant to health risk assessment among people without known diabetes when fasting glucose or HbA1c are difficult to obtain.
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