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71.
Magnetic resonance (MR) imaging has given mixed results in the detection of renal masses. To identify the reasons for this and to determine the optimal pulse sequences for evaluating renal tumors, the authors imaged 12 primary renal tumors in vivo and 17 in vitro at 0.35 T. Histopathologic findings for each specimen were closely correlated with the MR images. Four of seven solid tumors imaged in vivo were isointense with surrounding normal renal parenchyma at all pulse sequences. The other three tumors were hyperintense in vivo at T2-weighted sequences. At heavily T2-weighted sequences eight solid tumors were hyperintense in vitro and four were hypointense. There was no correlation between signal intensity and specific tissue type or histologic pattern for solid tumors. The five cystic tumors were well seen both in vivo and in vitro on T2-weighted images. However, the signal intensity of the cyst fluid was an unreliable indicator of benignancy. SE MR imaging at 0.35 T has significant limitations in the detection of solid renal masses.  相似文献   
72.
Diabetes mellitus encompasses a group of chronic metabolic conditions associated with cardiovascular complications such as atherosclerosis, cardiomyopathy and nephropathy. In the present study, the authors investigated the beneficial effects of swertiamarin in diabetes and its associated cardiovascular complications in Zucker fa/fa rats. Six male Zucker fa/fa rats in each group were treated for 28 days with swertiamarin (75 mg/kg/day, intraperitoneally) or pioglitazone (30 mg/kg orally). Blood samples were collected and evaluated for several parameters. Elevated serum glucose, triglyceride, nonesterified free-fatty acid and cholesterol levels were found in untreated Zucker fa/fa rats. Serum matrix metalloproteinase (MMP)-9 and MMP-3 levels were also found to be significantly higher in untreated Zucker fa/fa rats. Treatment with swertiamarin significantly (P<0.05) reduced serum glucose, triglyceride, nonesterified free-fatty acid and cholesterol levels, and also reduced serum MMP-9 and MMP-3 levels compared with untreated rats. Swertiamarin also significantly (P<0.05) decreased serum levels of urea compared with untreated Zucker fa/fa rats. Overall, the data suggest that swertiamarin produced beneficial effects with respect to diabetes-induced cardiovascular complications such as atherosclerosis and nephropathy. A swertiamarin-induced decrease in serum MMP-9 and MMP-3 levels is one of the possible mechanisms responsible for improvement of these complications.  相似文献   
73.
学术背景:平衡能力是人体的一项重要生理机能,在人类生活中有非常重要的意义.特别是老年人平衡能力下降,直接影响老年人独立生活能力,严重的会引起老年人跌倒,诱发其他疾病.目的:总结老年人平衡能力的国内外研究现状,并展望未来老年人平衡能力研究的发展方向.检索策略:应用计算机检索PubMed数据库1990-12/2007-06有关老年人平衡能力方面的文章,检索词“elderly,balance“,限定文章语言种类为English,共检索到208篇文章.同时应用计算机检索中国期刊全文数据库、万方数据库1997-12/2007-06的相关文章,检索词“老年人、平衡能力“,限定文章语言种类为中文,共检索到85篇文章.对资料进行初审,选取符合研究要求的有关文章找全文.纳入标准:①平衡能力的研究.②老年人平衡特征.③平衡能力评价.④运动干预对平衡能力的研究.排除理由:①较陈旧的文献.②重复研究.文献评价:共19个研究满足全部纳入标准,予以纳入.其中6篇为老年人平衡特征的文献、8篇平衡评价的文献、5篇运动干预老年人平衡影响的文献.资料综合:①平衡能力是人体相关系统功能的集中表现,研究影响平衡能力的前庭系统、视觉系统、躯体感觉、神经系统及肌肉-骨骼等系统功能增龄性的变化趋势,探究导致平衡能力增龄性变化的主要因素是待解决的问题.②平衡测试是定量评定平衡能力的前提,针对老年群体的特殊性,逐步寻求安全、简捷能全面反映其平衡能力的测试方法.③国内专业人员日益提高了对平衡的关注,发表的论文也较多,但由于平衡评定方法不统一,对中国人民平衡能力增龄性变化的研究没有继承性,研究国民的平衡能力增龄性变化是必要的.④众多研究表明,体育锻炼可以延缓平衡能力的衰退.但研究比较分散,运动项目比较单一,探究利于干预的运动项目以及最佳时机是待解决的热点课题.结论:建立一整套适合中国国民平衡能力评价体系,研究国民的平衡能力增龄性变化是十分有必要的,为全民健身活动中的老年人科学地进行健身提供依据.  相似文献   
74.
75.
Swift PGF, Skinner TC, de Beaufort CE, Cameron FJ, Åman J, Aanstoot H‐J, Castaño L, Chiarelli F, Daneman D, Danne T, Dorchy H, Hoey H, Kaprio EA, Kaufman F, Kocova M, Mortensen HB, Njølstad PR, Phillip M, Robertson KJ, Schoenle EJ, Urakami T, Vanelli M, Ackermann RW, Skovlund SE for the Hvidoere Study Group on Childhood Diabetes. Target setting in intensive insulin management is associated with metabolic control: the Hvidoere Childhood Diabetes Study Group Centre Differences Study 2005. Objective: To evaluate glycaemic targets set by diabetes teams, their perception by adolescents and parents, and their influence on metabolic control. Methods: Clinical data and questionnaires were completed by adolescents, parents/carers and diabetes teams in 21 international centres. HbA1c was measured centrally. Results: A total of 2062 adolescents completed questionnaires (age 14.4 ± 2.3 yr; diabetes duration 6.1 ± 3.5 yr). Mean HbA 1c = 8.2 ± 1.4% with significant differences between centres (F = 12.3; p < 0.001) range from 7.4 to 9.1%. There was a significant correlation between parent (r = 0.20) and adolescent (r = 0.21) reports of their perceived ideal HbA1c and their actual HbA1c result (p < 0.001), and a stronger association between parents' (r = 0.39) and adolescents' (r = 0.4) reports of the HbA1c they would be happy with and their actual HbA1c result. There were significant differences between centres on parent and adolescent reports of ideal and happy with HbA1c (8.1 < F > 17.4;p < 0.001). A lower target HbA1c and greater consistency between members of teams within centres were associated with lower centre HbA1c (F = 16.0; df = 15; p < 0.001). Conclusions: Clear and consistent setting of glycaemic targets by diabetes teams is strongly associated with HbA1c outcome in adolescents. Target setting appears to play a significant role in explaining the differences in metabolic outcomes between centres.  相似文献   
76.
危红兵  钮心懿 《药学学报》1990,25(12):881-885
用放射配体受体结合法测定表明:克塞平对多巴胺D1受体的亲和力较异戊塞平高近20倍。两药对其它各受体的亲和力差別不大。慢性给药后,异戊塞平和克塞平均能使大鼠脑皮层5-HT2受体的密度显著下降,而亲和力变化不明显。这种下调5-HT2受体的作用发生在给异戊塞平后1~2周之间,给克塞平后的2~3周之间。慢性给药3周,异戊塞平和克塞平均未使大鼠脑皮层的β受体密度及亲和力产生显著变化。  相似文献   
77.
Acute spinal cord injury: MR imaging at 1.5 T   总被引:19,自引:0,他引:19  
Thirty-seven magnetic resonance (MR) imaging studies were performed with a 1.5-T magnet and surface coils in 27 patients with suspected spinal cord injuries. Imaging was performed 1 day to 6 weeks after injury. Cord abnormalities were seen with MR in 19 patients, while skeletal and/or ligamentous injuries were seen in 21 (78%). Three types of MR signal patterns were seen in association with cord injuries. Acute intraspinal hemorrhage was seen in five patients with cord injuries and demonstrated decreased signal intensity on T2-weighted images obtained within 24 hours of injury. Cord edema and contusion had high signal intensity on T2-weighted images and were observed in 12 cases with cord injury. Neurologic recovery, determined in 16 patients, was insignificant in patients with intraspinal hemorrhage; however, patients with cord edema or contusion recovered significant neurologic function. MR at 1.5 T is extremely useful in the diagnosis of acute cord injury and also demonstrates potential in predicting neurologic recovery.  相似文献   
78.
Primary lymphoepithelioma-like carcinoma of the skin (LE-lCS) is a very rare cutaneous malignancy of uncertain origin. The neoplasm reveals typical morphological similarity to undifferentiated nasopharyngeal carcinoma (lymphoepithelioma). This case report presents a 47-year-old man with a 5 mm erythematous papule on dorsal nose of six months duration. The patient underwent complete surgical excision and is disease free 7 months later.  相似文献   
79.

Background

Angiocidin plays a key role in angiogenesis and tumor progression. High angiocidin expression is detected in some kind of solid tumors and tumor vascular endothelial cells. Several reports have shown the inhibition of angiogenesis and tumor growth caused by angiocidin. However, the role of angiocidin in liver cancers growth is still unclear.

Objectives

To examine angiocidin expression in SMMC-7221 and HepG2 cells and the role of angiocidin in liver cancer cell growth.

Methods

RT-PCR and western blot are used in this study to detect angiocidin expression. SiRNA and MTT experiments are used in exploring the role of angiocidin in tumor cell growth.

Results

Our study showed high angiocidin expression in two kinds of liver cancer cells. Angiocidin protein production in HepG2 cells were reduced significantly by siRNA. When HepG2 cells were transfected with siRNA-angiocidin, these cells showed very low proliferation activity compared with control cells. Our study suggests that reduction of angiocidin may contribute to decreased proliferation activity in liver cancer cells.

Conclusion

Angiocidin is highly expressed in liver cancer cells, and it may play a key role in tumor growth of liver cancers.  相似文献   
80.
运用模糊聚类方法分析中药微量元素含量与药效的关系   总被引:2,自引:0,他引:2  
目的:不同中药中各种微量元素的含量数据离散,从含量数据上很难说明不同药物的药物相似性,故运用模糊分类方法研究药物微量元素含量与药物疗效的关系,验证其在药物功效的相似性及不同种类中药定量指标评价方面的作用。方法:实验于2005-10/2006-11在吉林省中医药管理局中药微量元素分析实验室完成。用原子吸收分光光度法检测合欢花、黄芪、石菖蒲、远志、山楂、银杏叶、人参、元肉、蒲黄、酸枣仁、苏木11种中药中钾、钠、钙、镁、铁、铬、镍、锰、铜、锌元素的含量,结合锌/铜比值、镁/钙比值,以数据极差法进行统计指标的标准化处理,以数量积法算出衡量被分类对象之间的相关系数,确定论域上的模糊矩阵。结果:相关系数r=0.50时,合欢花,石菖蒲,远志,人参,元肉,蒲黄,酸枣仁7种药物聚类相似;相关系数r=0.65时,合欢花,石菖蒲,元肉,蒲黄,酸枣仁5种药物聚类相似;r=0.75时,合欢花,石菖蒲,蒲黄3种药物聚类相似。研究还发现:药物中金属元素含量丰富,而且相关系数较大的药物,其药物疗效相似。结论:运用数学与化学计量学方法建立模糊聚类分析模型,可以把离散的数据标准化处理,确定论域上的模糊矩阵可以研究不同药物间的药效相似性,可以对不同种类的中药进行定量指标的明确评价。  相似文献   
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