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Stephen MT Hoke Gaoyang Liang A Irina Mutiu Julie Genereaux Christopher J Brandl 《BMC biochemistry》2007,8(1):16
Background
Spt7 is an integral component of the multi-subunit SAGA complex that is required for the expression of ~10% of yeast genes. Two forms of Spt7 have been identified, the second of which is truncated at its C-terminus and found in the SAGA-like (SLIK) complex. 相似文献2.
van Pul C Roos FG Derksen OS Buijs J Vlaardingerbroek MT Kopinga K Wijn PF 《Magnetic resonance imaging》2004,22(9):1169-1180
In the neonatal brain, it is important to use a fast imaging technique to acquire all diffusion weighted images (DWI) for apparent diffusion coefficient (ADC) calculation. Taking into account the occurrence of typical echo planar imaging (EPI) artifacts, we have investigated whether single-shot (SSh) or multishot (MSh) DWI-EPI should be preferred. In 14 neonates, 17 adult patients and 5 adult volunteers, DWIs are obtained both with SSh and MSh EPI. The occurrence of artifacts and their influence on the ADC are explored and further quantified using simulations and phantom studies. Two radiologists scored overall image quality and diagnosability of all images. Single-shot and MSh DWI-EPI scored equally well in neonates with respect to overall image quality and diagnosability. In newborns, more motion artifacts in MSh can be noticed while N/2-ghost artifacts in SSh occur less frequently than in adults. Both N/2-ghost and motion artifacts result in significant ADC abnormalities. There is a serious risk that these artifacts will be mistaken for genuine diffusion abnormalities. N/2-ghost artifacts are hardly noticed in the neonatal brain, which might be due to smaller cerebrospinal fluid (CSF) velocity than in adults. Apparent diffusion coefficient values in MSh are unreliable if motion occurs. We conclude that for ADC calculations in neonates SSh DWI-EPI is more reliable than MSh. 相似文献
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M. T. Vlaardingerbroek 《Applied Scientific Research》1956,5(1):139-143
Summary Breakdown voltages of glow discharges in Ne and Ne-A mixtures as a function of the frequency will be discussed. The variation of the breakdown voltage with rising frequency can be understood qualitatively from buildup times and the increase of pre-breakdown current caused by particles remaining from previous periods.Thanks are due to prof. dr H. B. Dorgelo and ir A. W. van. Wagensveld for discussions on the subject. 相似文献
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