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排序方式: 共有1463条查询结果,搜索用时 15 毫秒
1.
Teng-Yi Huang Hsiao-Wen Chung Fu-Nien Wang Cheng-Wen Ko Cheng-Yu Chen 《Magnetic resonance in medicine》2004,51(2):243-247
In this work the feasibility of separating fat and water signals using the balanced steady-state free precession (SSFP) technique is demonstrated. The technique is based on the observation (Scheffler and Hennig, Magnetic Resonance in Medicine 2003;49:395-397) that at the nominal values of TE = TR/2 in SSFP imaging, phase coherence can be achieved at essentially only two orientations (0 degrees and 180 degrees ) relative to the RF pulses in the rotating frame, under the assumption of TR < T2, and independently of the SSFP angle. This property allows in-phase and out-of-phase SSFP images to be obtained by proper choices of the center frequency offset, and thus allows the Dixon subtraction method to be utilized for effective fat-water separation. The TR and frequency offset for optimal fat-water separation are derived from theories. Experimental results from healthy subjects, using a 3.0 Tesla system, show that nearly complete fat suppression can be accomplished. 相似文献
2.
Dinesh Bhugra 《Archives of sexual behavior》1997,26(5):547-557
The process of coming out among Western gay men and women is well described. The present study is the first to explore the experiences of coming out among gay men of South Asian origin in the U.K. South Asian is defined here as originating from the Indian subcontinent. Members of a homophile organization were given a questionnaire designed to assess the experiences of coming out to family and friends and the degree of compartmentalization in their lives. Information obtained from 52 questionnaires was supplemented by detailed interviews with 9 respondents. Families and religion played important roles in the process of coming out. Sisters were most likely to be told first. Some degree of dissonance between cultural and sexual identity was noted. In addition, each step taken in revealing one's sexual orientation to friends, family, and colleagues was dictated by the strength of the relationships and the desire for intimacy. Further areas of research are highlighted. 相似文献
3.
肺心病慢性呼吸性酸中毒合并代谢性酸碱失衡判断方法探讨(附80例次血气分析) 总被引:2,自引:0,他引:2
目的:对42例肺心病慢性呼吸性酸中毒患者的80例次血气测定结果。方法:用不同的酸碱图(卡)及代偿公式进行酸碱类型的初步差别分析。结果:结合临床表现、各种影响因素与治疗反应等作出综合判定。结论:比较二种判定的差异,并提出较为实用、可靠的判断建议,以助于复合型呼吸性酸碱失衡的临床诊断与处理。 相似文献
4.
目的 探讨大学生睡眠质量、负性情绪在错失恐惧与社交媒体倦怠间的中介作用。 方法 采用错失恐惧量表、社交媒体倦怠量表、匹兹堡睡眠质量指数量表、抑郁-焦虑-压力量表简体中文版对306名大学生进行调查。 结果 错失恐惧、社交媒体倦怠、睡眠质量和负性情绪之间呈两两正相关;错失恐惧能正向预测社交媒体倦怠;睡眠质量和负性情绪在错失恐惧和社交媒体倦怠之间起单独中介作用,且睡眠质量和负性情绪在错失恐惧与社交媒体倦怠之间起链式中介作用,负性情绪各维度效应皆成立。 结论 睡眠质量和负性情绪能够为错失恐惧对社交媒体倦怠的影响提供一个解释机制,大学生的错失恐惧既可以直接影响其社交媒体倦怠水平,也可以通过睡眠质量、负性情绪的独立中介效应以及睡眠质量-负性情绪的链式中介效应间接影响。 相似文献
5.
Qian BF El-Salhy M Melgar S Hammarström ML Danielsson A 《Clinical and experimental immunology》2000,120(3):424-433
Neuroendocrine peptides have a variety of physiological functions in the gastrointestinal tract. This study was carried out to investigate the impact of IL-2 deficiency on the neuroendocrine system in normal colon, and the neuroendocrine changes during colonic inflammation. Mice with homozygous disrupted IL-2 gene (IL-2-/-) spontaneously developed a bowel disease with similarities to human ulcerative colitis. Different types of colonic endocrine cells and myenteric nerves were analysed in the IL-2-/- mice using immunomorphometry. The neuropeptide contents in the colonic tissues were determined by radioimmunoassay. Age-matched healthy IL-2+/- and IL-2+/+ mice served as controls and the colonic IL-2 levels were compared between these two groups of mice by ELISA. Our data showed that less than half the amount of IL-2 was synthesized in the colon of IL-2+/- mice compared with the IL-2+/+ wild-type mice. Two major differences in the neuroendocrine colon were found between the mice with an intact and disrupted IL-2 gene. One was age-related. The frequencies of various endocrine cells and myenteric nerves increased with age in the IL-2+/+ mice. However, no such increases were seen in the mice with a disrupted IL-2 gene. Instead, the volume densities of enteroglucagon, serotonin cells and substance P (SP), vasoactive intestinal polypeptide (VIP) and total myenteric nerves were lower in the older IL-2+/- and IL-2-/- mice compared with the wild type. The other was disease-related. Polypeptide YY (PYY) cells and tissue levels of PYY, SP and VIP were significantly decreased in the IL-2-/- mice during the course of bowel inflammation compared with the healthy IL-2+/- and IL-2+/+ controls. These findings indicate that colonic neuroendocrine alterations did occur in the mice with a disrupted IL-2 gene and diminished local IL-2 level, suggesting a role of IL-2 in the regulation of the neuroendocrine system and a prevalent interaction between the immune and neuroendocrine systems in normal colon. On the other hand, there were some changes that seemed to correlate with the bowel inflammatory process. They might be associated with the impaired function in inflamed gut and contribute to the development and/or prolongation of disease. 相似文献
6.
目的为进一步深入研究Smad3基因在脊椎动物发育中的重要作用,对Smad3基因剔除小鼠进行保种和繁育研究.方法采用基因剔除杂合子小鼠进行保种,通过PCR和Southern杂交对杂合子小鼠交配所产生的后代进行基因型鉴定,纯合子小鼠和野生型小鼠用于表型分析,杂合子小鼠用于留种和繁殖生产.结果采用PCR方法对278只子代小鼠进行了基因型鉴定,83只为野生型,133只为杂合子,62只为纯合子.结论Smad3基因剔除突变能稳定遗传.采用杂合子小鼠保种,子代小鼠三种基因型比例符合孟德尔遗传定律. 相似文献
7.
贫血患者血清铁铁蛋白细胞内外铁检测结果分析 总被引:2,自引:0,他引:2
目的探讨各类贫血患者血清铁、铁蛋白和骨髓细胞内外铁含量多或寡与贫血症的相互关系.方法应用比色法、放射免疫法和普鲁士兰反应法检测186例各种贫血患者血清铁、铁蛋白浓度和细胞内外铁粒、铁小珠的含量.结果急、慢性白血病贫血、再生障碍性贫血、铁粒幼红细胞性贫血、溶血性贫血、巨幼红细胞性贫血患者血清铁浓度升高;肾性贫血、肝性贫血、缺铁性贫血、肿瘤性贫血、骨髓增生异常综合症(MDS-RA)患者血清铁下降;铁蛋白增高主要见于急、慢性白血病贫血和铁粒幼红细胞性贫血、肿瘤性贫血及骨髓增生异常综合症等;细胞内外铁颗粒减少和外铁消失主要见于缺铁性贫血和肾性贫血.结论检测血清铁、铁蛋白和细胞内外铁能灵敏地反映机体铁的贮存和利用水平;恶性肿瘤或其它细胞快速增殖时,细胞合成铁蛋白的能力较强. 相似文献
8.
[背景 ]胫腓骨骨折的治疗方法较多 ,小切口复位有较多的优点 .[病例报告 ]总结分析了 86例胫腓骨骨折病人用小切口骨折复位外固定器固定的治疗情况 .切口Ⅰ期愈合 .平均随访 1年 ,全部获得骨性愈合 ,愈合时间为 6~ 14个月 ,平均 8个月 .[讨论 ]小切口骨折复位外固定器治疗胫腓骨骨折是一种简单、有效的方法 相似文献
9.
广西卫Ⅵ项目实施与效果评价 总被引:2,自引:0,他引:2
1995年,广西壮族自治区开始实施卫Ⅵ项目,共有30个项目县。各级政府和卫生职能部门,注意以项目为龙头,以重点、难点为突破口,做到项目目标明确,工作职责分清,措施落实到位,做好分类指导,加强监督检查,从而保证项目顺利进行,使项目工作取得了明显效果。至1998年底止,项目的16个指标已基本达标,其中有12个指标已达到了项目终期目标要求,有力地推动了全区妇幼卫生事业的发展。 相似文献
10.