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101.
戊二醛交联提高胶原/壳聚糖真皮支架抗细胞收缩能力的研究 总被引:2,自引:0,他引:2
目的 应用交联处理的胶原支架,来减缓其降解过多、易收缩变形、机械性能不足等缺点.方法 采用冷冻-冻干法构建胶原/壳聚糖多孔支架,并通过戊二醛交联构建具有良好抗细胞收缩稳定性和细胞相容性的胶原支架.通过测定不同培养时间各类支架的尺寸变化,研究了戊二醛交联对支架抗细胞收缩能力的影响.结果 戊二醛交联后的胶原/壳聚糖支架未见明显收缩,其细胞活性也始终高于干热交联支架.结论 戊二醛能有效地提高胶原基支架的抗细胞收缩能力,并保持其良好的生物相容性. 相似文献
102.
Fan Gao Mark L Latash Vladimir M Zatsiorsky 《Journal of hand therapy》2007,20(4):300-7; quiz 308; discussion 309
The tight coupling between load (L) and grip (G) forces during voluntary manipulation of a hand-held object is well established. The current study is to examine grip-load force coupling when motion of the hand with an object was either self-generated (voluntary) or externally generated. Subjects performed similar cyclic movements of different loads at various frequencies with three types of manipulations: 1) voluntary oscillation, 2) oscillating the right arm via the pulley system by the left leg (self-driven oscillation), and 3) oscillating the arm via the pulley system by another person (other-driven oscillation). During the self-generated movements: 1) the grip forces were larger and 2) grip-load force modulation was more pronounced than in the externally generated movements. The G-L adjustments are not completely determined by the mechanics of object motion; nonmechanical factors related to movement performance, for instance perceptual factors, may affect the G-L coupling. 相似文献
103.
Liesbeth Vandenput Fernand Labrie Dan Mellstr?m Charlotte Swanson Thomas Knutsson Ralph Peeker Osten Ljunggren Eric Orwoll Anna L Eriksson Jan-Erik Damber Claes Ohlsson 《Journal of bone and mineral research》2007,22(2):220-227
Androgens are important regulators of bone and prostate health in elderly men. The role of serum levels of glucuronidated androgen metabolites as predictors of BMD and prostate volume in men is unclear. We show that specific glucuronidated androgen metabolites predict BMD and prostate volume in elderly men. INTRODUCTION: Androgens are important regulators of bone and prostate health in elderly men. Local synthesis and degradation of androgens are likely to be important parameters of biological action of androgens in androgen-responsive tissues. The aim of this study was to determine the role of serum levels of glucuronidated androgen metabolites as predictors of BMD and prostate volume in elderly men. MATERIALS AND METHODS: A subsample of the population-based Swedish part of the MrOS study (n = 631, average age = 75.9 years) was investigated. Bone parameters were measured using DXA. Serum levels of total testosterone (T) and dihydrotestosterone (DHT) were measured by gas chromatography/mass spectroscopy (GC-MS); androstane-3alpha,17beta-diol-3glucuronide (3G) and androstane-3alpha,17beta-diol-17glucuronide (17G) were measured by liquid chromatography/mass spectroscopy. Prostate volume (n = 159) was measured by transrectal ultrasound. RESULTS: The general pattern is that two of the glucuronidated androgen metabolites, namely 17G and 3G, are stronger positive predictors of BMD than the bioactive androgens (T and DHT). In addition, 17G is a clear positive predictor of prostate volume, explaining 4.5% of the variance in prostate volume, whereas the bioactive androgens do not display any association with prostate volume. CONCLUSIONS: Serum levels of specific glucuronidated androgen metabolites predict BMD and prostate volume in elderly men. Future studies should determine if the glucuronidated androgen metabolites also reflect other biological correlates of androgenic activity, including prostate cancer, and if low levels might be a marker of general androgen deficiency in men. 相似文献
104.
105.
Deborah A Cahn-Weiner Sarah Tomaszewski Farias Laura Julian Danielle J Harvey Joel H Kramer Bruce R Reed Dan Mungas Margaret Wetzel Helena Chui 《Journal of the International Neuropsychological Society》2007,13(5):747-757
Impaired ability to conduct daily activities is a diagnostic criterion for dementia and a determinant of healthcare services utilization and caregiver burden. What predicts decline in instrumental activities of daily living (IADLs) is not well understood. This study examined measures of episodic memory, executive function, and MRI brain volumes in relation to baseline IADLs and as predictors of rate of IADL change. Participants were 124 elderly persons with cognitive function between normal and moderate dementia both with and without significant small vessel cerebrovascular disease. Random effects modeling showed that baseline memory and executive function (EXEC) were associated with baseline IADL scores, but only EXEC was independently associated with rate of change in IADLs. Whereas hippocampal and cortical gray matter volumes were significantly associated with baseline IADL scores, only hippocampal volume was associated with IADL change. In a model including cognitive and neuroimaging predictors, only EXEC independently predicted rate of decline in IADL scores. These findings indicate that greater executive dysfunction at initial assessment is associated with more rapid decline in IADLs. Perhaps executive function is particularly important with respect to maintaining IADLs. Alternatively, executive dysfunction may be a sentinel event indicating widespread cortical involvement and poor prognosis. 相似文献
106.
实验性隐睾术后大鼠附睾的反应性变化 总被引:4,自引:1,他引:3
本研究描述了实验性隐睾术后大鼠附睾的形态学变化。结果表明,隐睾术后由于腹温作用和附皋管管腔内容物的改变,附睾管上皮细胞的形态和功能明显改变。术后早期上皮细胞出现无丝分裂相,上皮细胞的分泌和吞噬功能加强,胞质内含PAS阳性颗粒的细胞增多。随术后时间的延长,附睾上皮细胞变化逐渐趋于稳定。[ 相似文献
107.
乳管镜对乳腺导管内疾病的诊断及介入治疗--附100例临床分析 总被引:5,自引:2,他引:3
高学忠 《中国中西医结合外科杂志》2006,12(1):14-16
目的:探讨乳管镜在乳腺疾病诊断和治疗中的作用.方法:应用乳腺纤维导管内视镜对100例伴乳头溢液的乳腺导管性疾病进行诊断或介入治疗.结果:13例导管内占位性疾病得到了正确诊断,87例渗出性导管病经治疗后治愈.结论:乳管镜对乳管内病变的正确诊断及手术方式可提供依据,并可对渗出性病变进行介入治疗. 相似文献
108.
109.
首例中国可视化人体心脏三维重建及临床意义 总被引:5,自引:1,他引:4
目的 对首例中国数字化可视人体的心脏进行三维重建,为心脏疾病的影像学诊断和外科手术提供三维解剖学依据。方法 将首例中国数字化可视人体心脏部分的薄层断面(层厚1.0mm)输入SGI工作站,经数据分割、对位重建、平滑处理和三维显示等步骤,完成对心脏结构的三维重建。结果 本研究完整地重建出了心脏结构,重建的结构能够以多结构、多彩色实体模型方式显示,可显示心脏内部各结构的空间位置和毗邻关系,可在三维空间伴置上绕任意轴旋转任意角度。结论 重建出的三维图像清晰地显示了心脏内部和整体的结构,实现了心脏的二维可视化。 相似文献
110.
肱骨干骨折--髓内钉与钢板固定的比较 总被引:1,自引:1,他引:0
MohidBhandari JosephR BeateP.Hanson DanC.Norvell 《中华创伤骨科杂志》2004,6(6):676-680
总体而言,这些报道提示:采用髓内钉治疗肱骨干骨折较采用钢板带来更多的并发症,尤其是采用顺行人路。同时,这些报道没有提供确切的证据证明何种方法在骨折愈合、减少感染或上肢总体功能上优于另一种。 相似文献