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排序方式: 共有269条查询结果,搜索用时 15 毫秒
81.
Volkan Etus Hasan Tahsin Sarisoy Savas Ceylan 《Journal of clinical neuroscience》2006,13(6):643-7; discussion 648
Cervical and thoracic myelomeningocoeles differ from common lumbosacral myelomeningocoeles in many respects. We review the surgical technique and outcome achieved for a series of six infants who underwent surgery for cervical or thoracic myelomeningocoele. Five patients, who had intradural exploration and microsurgical untethering of the spinal cord, were neurologically stable on follow-up. The other patient, who had a simple subcutaneous resection of the sac without release of the intradural tethering bands, was re-operated on 16 months later, with progressive neurological symptoms due to cord tethering. Following re-exploration and microsurgical untethering of the spinal cord, the neurological deficits significantly improved. We suggest that the surgical technique in these lesions should include careful intradural exploration and microsurgical release of the spinal cord by meticulous resection of all tethering bands. This enables postoperative neurological improvement and possible prevention of future neurological deficits due to cord tethering. 相似文献
82.
萘甲异喹(NI)呈浓度依赖性地降低离体豚鼠心房收缩力和频率。其拮抗豚鼠左房肌Iso正性肌力作用的PD22′值为5.4,Ver为5.8。NI10μmol/L明显降低豚鼠乳头肌收缩力;缩短快反应APD,以对APD20影响最大,但不影响APA和Vmax。对高K+去极化慢反应动作电位,NI产生浓度依赖性负性肌力作用,同时明显降低APA,Vmax,缩短APD;提高细胞外液Ca2+浓度可使其抑制作用逆转。结果提示NI具有钙通道阻滞作用。 相似文献
83.
Volume calculation by means of SPECT: analysis of imaging acquisition and processing factors 总被引:1,自引:0,他引:1
To assess the effect of image acquisition and processing factors on the volume calculated from single photon emission computed tomography (SPECT) images, the authors evaluated technical factors including image matrix size, size of the region of interest (ROI), activity concentration in the region, amount of background subtraction, type of reconstruction filter, section thickness, and number of projections. They found that the percentage of background subtraction was the single most important factor affecting volume calculation. The smaller the volume, the greater the amount of background subtraction needed before the ROI is drawn. As an acceptable means to circumvent the varying percentage of background subtraction for different volumes, a calibration curve was constructed relating the true volume with the calculated volume for a fixed percentage of background subtraction. The use of a 128 X 128 acquisition matrix and zooming of the reconstructed images were necessary for accurate calculation of volumes smaller than 300 mL. 相似文献
84.
85.
测定咖啡因代谢物评价 N-乙酰转移酶、CYP1A2和黄嘌呤氧化酶活性 总被引:8,自引:0,他引:8
目的是对中国人N-乙酰化酶(NAT2)、CYP1A2酶和黄嘌呤氧化酶(XO)的活性进行分析。120名健康志愿者饮用3杯咖啡后于4~5h留尿,用HPLC方法测定尿中5种咖啡因主要代谢物浓度,即5-乙酰胺基-6-甲酰胺基-3-甲基尿嘧啶(AFMU)、1-甲基黄嘌呤(1X)、1-甲基尿酸(1U)、1,7-二甲基尿酸(17X)、1,7-二甲基黄嘌呤(17U)。其中N-乙酰化酶活性用AFMU/1X或AFMU/(AFMU+1X+1U)表示;CYP1A2酶活性指标采用(AFMU+1X+1U)/17X或AFMU+1X+1U)/17U;XO酶活性指标采用1U/1X或1U/(1X+1U)。结果表明,N-乙酰化酶活性呈两态分布,慢代谢者占16.7%,CYP1A2和XO酶活性呈对数正态分布,其代谢比值与国外文献报道一致。提示通过测定咖啡因代谢物比值,可以进行NAT2酶、CYP1A2酶和黄嘌呤氧化酶活性分析。 相似文献
86.
Molecular phenotype of a human lymphoblastoid cell-line homoplasmic for the np 7445 deafness-associated mitochondrial mutation 总被引:7,自引:1,他引:6
We have studied mitochondrial gene expression and metabolic function in a
human lymphoblastoid cell-line homoplasmic for the np 7445, deafness-
associated mitochondrial DNA mutation. The mutation maps to the 3' termini
of the oppositely oriented genes encoding cytochrome oxidase subunit I
(COI) and tRNA-ser(UCN). In comparison with control lymphoblastoid cells,
we detected a marked depletion (> 60%) of tRNA- ser(UCN). There was,
however, no significant impairment of respiratory function, no alteration
to the structure or abundance of COI mRNA or its precursors, and no
detectable abnormality of mitochondrial protein synthesis. We also found
considerable tissue-variation in the abundance of tRNA-ser(UCN). We propose
that the tissue-specific phenotype associated with this mutation results
from an inherent deficiency in the processing of the mutant pre-tRNA, that
becomes limiting for protein synthesis only in a restricted set of cells of
the auditory system in which the tRNA is, for other reasons, already at a
critically low level.
相似文献
87.
Daniel W. Visscher MD Niru Padiyar MD Dan Long HT Pam Tabaczka BS MT 《The breast journal》1998,4(6):447-451
Abstract: The growth of invasive breast carcinoma is facilitated by abnormal expression of estrogen receptor (ER), however, the status of ER during disease histogenesis is poorly defined. The extent of ER immunostaining (expressed as percentage of positive cells) was semiquantitated in the invasive (ICA) and corresponding in situ (CIS) components of 50 formalin-fixed, paraffin-embedded breast carcinomas and then compared to staining in normal terminal duct lobular units (TDLU) or hyperplastic lesions (if present) in the same tissue sections. Morphologically normal TDLUs from most cases (61%) exhibited ER staining in 11–30% of epithelial cells; only 10% of the cases had TDLUs demonstrating immunoreactivity in more than 50% of cells. In contrast, 80% of the hyperplastic lesions showed ER staining in more than 30% of epithelial cells, with 44% demonstrating immuoreactivity in more than 50% of epithelial cell nuclei (p = 0.01, chi-square test). Although most in situ carcinomas showed even more extensive ER staining than hyperplasias (>70% of cells were positive in 50% of cases), a significant subset (28%) of CIS exhibited staining in less than 10% of cells (p = 0.002, chi-square test). Invasive carcinomas were less often extensively immunoreactive (i.e., >50% of cells positive) than CIS (32% versus 58% for CIS) and there were five cases (10%) in which the CIS component was ER positive but the invasive component was ER negative. Finally, ER-positive carcinomas were significantly more often accompained by extensive CIS and/or proliferative breast disease (p = 0.007 and 0.003, respectively). The divergent levels of ER expression observed between premalignant, preinvasive, and invasive lesions suggests that inappropriate regulation of hormone receptors may be a factor that promotes early growth or progression in breast neoplasia, and ER-positive breast carcinomas are characterized by a different, possibly lengthier, histogenesis than ER-negative malignancies with a greater frequency of background hyperplastic lesions and a larger preinvasive component. 相似文献
88.
西山医院脊髓损伤功能量表内容介绍 总被引:1,自引:3,他引:1
目的:介绍一套新的脊髓损伤功能评价量表。方法:综合目前使用的各种常用脊髓功能量表,结合实际工作经验及脊髓损伤患者神经功能改善特点,制定了西山医院脊髓损伤功能量表。结果:西山医院脊髓损伤功能量表共分9大项16小项,采用4分制,正常为3分,最差为0分。总分0~48分,0~16分为重度残障,17~32分为中度残障;33~47分为轻度残障,48分正常。量表包括上肢运动功能(饮食、梳洗、书写)、下肢运动功能(站立、行走)、躯干运动功能(坐、翻身)、全身运动功能(床椅转移、穿脱衣服、洗澡)、括约肌功能(膀胱功能、直肠功能)、肌张力、泌汗、皮肤营养、疼痛、性功能。结论:西山医院脊髓损伤功能量表是一套专门应用于脊髓损伤患者功能评价量表。该量表能全面、精确评定患者功能,简便实用、费时短。应用这份功能量表,既能客观反映患者的功能变化,随访时又不增加患者负担,同时也能减轻医务工作者的负担。 相似文献
89.
目的:对晚期脊髓损伤患者开展嗅鞘细胞再移植治疗,探讨其对神经功能的继续改善效果。方法:①患者男性,27岁,哈萨克斯坦籍,2001年9月20日遭霰弹枪击急诊手术后,双下肢不能运动及感觉消失,尿便失禁,右下肢阵发性钝痛。诊断为陈旧性完全性脊髓损伤(T12),美国脊髓损伤协会标准脊髓功能分级为A级。2002年9月30日第1次行脊髓胚胎嗅鞘细胞移植术,2007年2月5日行第2次脊髓胚胎嗅鞘细胞移植术。治疗方案患者知情同意。②取4个月流产胚胎(孕妇及其家属均知情同意)的嗅球,消化成单个嗅鞘细胞后培养2周,细胞浓度约2×1010L-1。于患者相应脊髓损伤上端(平T11椎体)做1个锁孔,直径约3cm,在脊髓损伤部位与正常脊髓交界处沿中线于无血管区,分两点用4.5号细针共注入100μL(第1次手术)、50μL(第2次手术)嗅鞘细胞悬液,细胞数均为1×106个。第2次移植术前进行供、受体细胞HLA配型,术后口服FK506胶囊2mg,2次/d,共42d。结果:①第1次术后3个月,排尿能控制6h,双足运动功能改善,性功能改善,阴茎勃起功能改善,疼痛减轻。②第2次术后10d,双下肢双足皮肤泌汗功能改善,右下肢疼痛减轻,腹部皮肤感觉稍有好转,针刺觉左侧由术前T10皮节消失好转至T10减退。较第2次移植前椎旁躯体感觉诱发电位有所改善,双侧椎旁电位从T10下降到T12。结论:胚胎嗅鞘细胞二次移植能继续改善晚期脊髓损伤患者的神经功能。但移植的细胞数量、容积、注射点位置等需深入探讨。 相似文献
90.
目的:观察胎盘免疫调节因子对大鼠子宫内膜异位症动物模型的治疗效果和对大鼠免疫功能的影响。方法:实验于2005-10/2006-12在广西医科大学医学科学实验中心及广西肿瘤防治研究所实验病理室完成。①实验材料:健康6个月龄雌性SD大鼠60只,体质量为200~250g;健康产妇胎盘在经广西医科大学第一附属医院伦理委员会同意和产妇知情同意后获得。②实验干预及分组:利用自体子宫组织移植的方法,建立雌性子宫内膜异位症大鼠模型40只,随机分为胎盘免疫调节因子小剂量组、中剂量组、高剂量组和模型对照组,分别肌注胎盘免疫调节因子剂量为0.375,0.75,1.5mg/kg和等体积生理盐水,1次/d,连续8周。③用两脚规测量移植物的体积(V=长×宽×高/mm3),采用ATP生物荧光法测定大鼠脾细胞增殖能力;采用中性红法测定腹腔巨噬细胞的吞噬功能。采用ELISA法检测治疗后各组大鼠血清中白细胞介素2水平。结果:建模成功40只,均进入结果分析。①各组移植物外观及体积:用药后8周,各胎盘免疫调节因子组移植物体积不同程度缩小(P<0.05),呈扁平状,粘连受到明显的抑制。②各组大鼠脾细胞增殖试验、腹腔巨噬细胞吞噬功能及血清白细胞介素2水平的变化:胎盘免疫调节因子中,高剂量用药组脾细胞增殖能力较模型对照组升高(P<0.05);各剂量胎盘免疫调节因子组腹腔巨噬细胞吞噬功能、白细胞介素2水平均较模型对照组升高(P<0.05)。结论:胎盘免疫调节因子治疗大鼠子宫内膜异位症显示了较好的疗效,可显著缩小子宫异位内膜的体积,提高大鼠的免疫功能。 相似文献