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Winkler  ML; Olsen  WL; Mills  TC; Kaufman  L 《Radiology》1987,165(1):203-207
Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study.  相似文献   
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We report a case of renal transplant ureteral obstruction caused by a cyclosporine-associated B cell lymphoproliferative disorder. The interaction of cyclosporine with Epstein-Barr virus infections and the predisposition towards B cell lymphoproliferative disorders are reviewed. The characterization of these tumors by deoxyribonucleic acid hybridization studies and a review of the clinical experience treating these disorders also are presented.  相似文献   
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Alcohol use and depression symptoms among employed men and women.   总被引:2,自引:1,他引:1       下载免费PDF全文
A representative sample of 1,367 employed men and women in Detroit responded to questions about drinking practices and symptoms of depression. After controlling for age, education, family income, marital status, medication use, fathers' drinking, and other variables, increased quantity of alcohol consumed per drinking occasion was associated with increased depression symptoms in the sober state among men and women. Depression symptoms may be one of a group of not fully identified drug after-effect disorders involving psychological functioning.  相似文献   
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The Bethlem myopathy is a rare autosomal dominant proximal myopathy characterized by early childhood onset and joint contractures. Evidence for linkage and genetic heterogeneity has been established, with the majority of families linked to 21q22.3 and one large family linked to 2q37, implicating the three type VI collagen subunit genes, COL6A1 (chromosome 21), COL6A2 (chromosome 21) and COL6A3 (chromosome 2) as candidate genes. Mutations of the invariant glycine residues in the triple-helical domain-coding region of COL6A1 and COL6A2 have been reported previously in the chromosome 21-linked families. We report here the identification of a G-->A mutation in the N-terminal globular domain-coding region of COL6A3 in a large American pedigree (19 affected, 12 unaffected), leading to the substitution of glycine by glutamic acid in the N2 motif, which is homologous to the type A domains of the von Willebrand factor. This mutation segregated to all affected family members, to no unaffected family members, and was not identified in 338 unrelated Caucasian control chromosomes. Thus mutations in either the triple-helical domain or the globular domain of type VI collagen appear to cause Bethlem myopathy.   相似文献   
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0 引言为了克服离子选择电极(ISE)法的微量电位信号极易受环境温度变化及电子噪声的干扰问题,该仪器采用了参考电极,把参考电极与其测定电极装在同一测量室内,保持其相同的物理环境,使干扰源对所有电极的影响相同. 以内参液作为参考电极的测量对象,测得一个参考电极电位值,再测样品的电极电位值,二者相抵就消除了所叠加的干扰信号.  相似文献   
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Cancer is a leading cause of death worldwide and affects society in terms of the number of lives lost. Current cancer treatments are based on conventional chemotherapy which is nonspecific in targeting cancer. Therefore, intensive efforts are underway to better target cancer-specific cells while minimizing the side effects on healthy tissues by using LDL particles as active drug delivery vehicles. The goal is to encapsulate anticancer agents thiosemicarbazone metal-ligand complexes into LDL particles to increase the cytotoxic effect of the agent by internalization through LDL receptors into MCF7, A549, and C42 cancer cell lines as segregate models for biological evaluations targeting tubulin. Zeta potential data of LDL-particles encapsulated anticancer agents showed an acceptable diameter range between 66–91 nm and uniform particle morphology. The results showed cell proliferation reduction in all tested cell lines. The IC50 values of LDL encapsulated thiosemicarbazone metal-ligand complexes treated with MCF7, A549, and C42 ranged between 1.18–6.61 µM, 1.17–9.66 µM, and 1.01–6.62 µM, respectively. Western blot analysis showed a potent decrease in tubulin expression when the cell lines were treated with LDL particles encapsulated with thiosemicarbazone metal-ligand complexes as anticancer agents. In conclusion, the data provide strong evidence that LDL particles are used as an active drug delivery strategy for cancer therapy.  相似文献   
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