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A novel balanced SSFP technique for the separation or suppression of different resonance frequencies (e.g., fat suppression) is presented. The method is based on applying two alternating and different repetition times, TR(1) and TR(2). This RF scheme manipulates the sensitivity of balanced SSFP to off-resonance effects by a modification of the frequency response profile. Starting from a general approach, an optimally broadened stopband within the frequency response function is designed. This is achieved with a TR(2) being one third of TR(1) and an RF-pulse phase increment of 90 degrees . With this approach TR(2) is too short ( approximately 1 ms) to switch imaging gradients and is only used to change the frequency sensitivity. Without a significant change of the spectral position of the stopband, TR(1) can be varied over a range of values ( approximately 2.5-4.5 ms) while TR(2) and phase cycling is kept constant. On-resonance spins show a magnetization behavior similar to balanced SSFP, but with maximal magnetization at flip angles about 10 degrees lower than in balanced SSFP. The total scan time is increased by about 30% compared to conventional balanced SSFP. The new technique was applied on phantoms and volunteers to produce rapid, fat suppressed images. 相似文献
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Andreas Lange Claudia Kistler Tanja B. Jutzi Alexandr V. Bazhin Claus Detlev Klemke Dirk Schadendorf Stefan B. Eichmüller 《Experimental dermatology》2009,18(6):527-535
Abstract: The identification of tumor-specific proteins located at the plasma membrane is hampered by numerous methodological pitfalls many of which are associated with the post-translational modification of such proteins. Here, we present a new combination of detergent fractionation of cells and of subtractive suppression hybridization (SSH) to gain overexpressed genes coding for membrane-associated or secreted proteins. Fractionation of subcellular components by digitonin allowed sequestering mRNA of the rough Endoplasmatic reticulum and thereby increasing the percentage of sequences coding for membrane-bound proteins. Fractionated mRNAs from the cutaneous T-cell lymphoma (CTCL) cell line HuT78 and from normal peripheral blood monocytes were used for SSH leading to the enrichment of sequences overexpressed in the tumor cells. We identified some 21 overexpressed genes, among them are GPR137B, FAM62A, NOMO1, HSP90, SLIT1, IBP2, CLIF, IRAK and ARC. mRNA expression was tested for selected genes in CTCL cell lines, skin specimens and peripheral blood samples from CTCL patients and healthy donors. Several of the detected sequences are clearly related to cancer, but have not yet been associated with CTCL. qPCR confirmed an enrichment of these mRNAs in the rough endoplasmic reticulum fraction. RT-PCR confirmed the expression of these genes in skin specimens and peripheral blood of CTCL patients. Western blotting verified protein expression of HSP90 and IBP2 in HuT78. GPR137B could be detected by immunohistology in HuT78 and in keratinocytes of dysplastic epidermis, but also in sweat glands of healthy skin. In summary, we developed a new technique, which allows identifying overexpressed genes coding preferentially for membrane-associated proteins. 相似文献
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心先安佐治小儿病毒性心肌炎临床疗效分析 总被引:1,自引:0,他引:1
目的:分析心先安佐治小儿病毒性心肌炎的临床疗效。方法:136例病毒性心肌炎患儿随机分为治疗组及对照组,在相同的 基础治疗条件下,治疗组应用心先安2~5mg kg,加液静滴,每天2次。结果:心先安组;痊愈51例(75%),好转12例(17.65%),无效5例(7. 35%),总有效92.65%。对照组痊愈41例(60.29%),好转14例(20.59%),无效13例(19.12%),总有效80.88%。两组相比、差异有显著性 (x2=4.09,P<0.005)。结论:心先安治疗小儿病毒性心肌炎疗效确切,且安全、可靠。 相似文献
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广西急性散发性病毒性肝炎的血清流行病学研究 总被引:2,自引:0,他引:2
对广西166例住院急性散发性病毒性肝炎病毒性肝炎病例进行血清流行病学调查研究,结果表明,甲型,乙型,丙型,戊型,庚型肝炎生期感染指标检出率分别为4.82%,51.20%,13.86%和11.64%,未分病例占17.42%,危险性因素分析表明,乙肝、丙肝和庚肝病人中有较高的肝病史、输血史和手术史。认为乙肝在急性散病毒性肝炎中占重要地位,医源性传播是主要传播途径 。 相似文献
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