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101.
Wei Han Ming-Xing Xie Qing Lv Xin-Fang Wang Li Zhang 《Frontiers of Medicine in China》2010,4(1):71-76
The recent development of 2-dimensional strain (2D strain) imaging can provide a powerful alternative for assessing left ventricular
(LV) torsion. This study was conducted to evaluate the global and regional left ventricular twist by 2D strain in patients
with anterior wall myocardial infarction (AMI). A total of 55 AMI patients were divided into two groups according to their
ejection fraction (EF) values (group A: LVEF ⩾ 50%; group B: LVEF < 50%), and 35 normal people served as the control group.
Using 2-dimensional strain software, global and regional LV rotation and displacement were obtained at two planes. Compared
with the control group, patients of group A showed reduced peak LV twist of the anterior and anterior-septal wall (9.26±1.89
vs 10.74±2.67; 9.71±1.71 vs 11.36±2.29, both P < 0.05), but the radial displacement and global twist were maintained (P > 0.05). Differently, regional and global LV twist and radial displacement in patients of group B deceased significantly,
especially in the anterior and anterior-septal wall, as compared with patients in the control or group A (both P < 0.05). Moreover, a strong correlation was noted between peak twist and radial displacement; the twist-displacement loop
was markedly distorted in patients of group B. This study demonstrated that 2D strain has a potential ability for quantification
of left ventricular global and segment twist and radial displacement in patients with coronary artery disease. 相似文献
102.
103.
YOU Han XIAO Bing CUI Da-Xiang SHI Yong-Quan FAN Dai-Ming 《World journal of gastroenterology : WJG》1998,4(4)
AIM To clone novel gastric cancer-associated genes and investigate their roles in gastric cancer occurrence.METHODS A method called differential display was used which allows the identification of differentially expressed genes by using PAGE to display PCR-amplified cDNA fragments between gastric cancer cells and normal gastric mucosa cells. These fragments were cloned into plasmid vector pUC18. Homology analysis was made after sequencing these fragments.RESULTS Two novel genes were identified compared with sequences from GenBank. One was registered with the AD number AF 051783. In situ hybridization showed that these two novel genes expressed specifically in gastric cancer tissues.CONCLUSION The two novel genes obtained by differential display were confirmed to be gastric cancer-associated genes using in situ hybridization. 相似文献
104.
Using a two‐stage global scan design, we analyzed general population replicates 1 and 42 of the Genetic Analysis Workshop (GAW) 12 simulated data set using three methods: revisited Haseman‐Elston (HER), maximum likelihood variance estimation (ML), and variance components (VC). Three marker densities, 5‐, 10‐, and 15‐cM intervals, were examined in the first‐stage scan. We found that the 10‐cM interval appears to be the most cost‐effective approach in genotyping without sacrificing power when using a first stage significance level of 0.01. Subsequently, we performed the second‐stage scan at 1‐cM intervals for those putative positive regions identified in the first‐stage scan at a significance level of 0.01. We also compared the power to detect linkage using different numbers of sib pairs for a genome‐wide scan at a 10‐cM interval and found that power decreases nonlinearly as the number of sib pairs decreases. © 2001 Wiley‐Liss, Inc. 相似文献
105.
我国环卫设备的现状与发展趋势——环卫设备的标准化、系列化 总被引:1,自引:0,他引:1
介绍了我国环卫设备的发展现状,并提出了存在的一些问题.根据我国环卫产业政策的有关要求:论述了各种环卫设备研究和开发的方向,指出大力推进环卫机械设备的标准化、系列化、通用化、规模化是社会主义市场经济发展和环卫业发展的需要. 相似文献
106.
基于Lyapnuov泛函方法,研究了满足匹配条件的不确定性时滞系统的鲁棒稳定性及具有稳定度β〉0鲁棒稳定性,给出了已有结果不能推出的新判据。这些新判据对已有结果难以使用的情况下也可有是有效的,或有时减少了已有结果的保守性。 相似文献
107.
本实验用分析基因限制性内切酶片段长度多态性(Restriction fragment length olymorphisms,RFLPs)技术,检测到中国人载脂蛋白AI(Apolipoprotein AI。Apo AI)基因3′端存一PstI多态位点,并发现该多态位点与低高密度脂蛋白(HDL)血症及冠心病有较密切的关系。 相似文献
108.
W K Moon M H Han I O Kim M W Sung K H Chang S W Choo M C Han 《AJNR. American journal of neuroradiology》1995,16(4):997
We report a case of congenital fistula from ectopic accessory parotid gland to the cheek demonstrated by CT sialography and CT fistulography. The right parotid gland was abnormally located lateral to masseter muscle. The fistula was arising from an ectopic accessory parotid gland with ectopic duct positioned anterior to masseter muscle. CT sialography and CT fistulography were very helpful in the diagnosis and surgical planning. 相似文献
109.
Partial splenic embolization for hypersplenism concomitant with or after arterial embolization of hepatocellular carcinoma in 30 patients 总被引:15,自引:0,他引:15
Ming-Jun Han Han-Guo Zhao Ke Ren Dong-Chun Zhao Ke Xu Xi-Tong Zhang 《Cardiovascular and interventional radiology》1997,20(2):125-127
Purpose To study the value of partial splenic embolization (PSE) for the treatment of hypersplenism in patients undergoing embolization
of hepatocellular carcinoma (HCC).
Methods Transcatheter hepatic arterial embolization (THAE) combined with PSE was performed in 30 patients with HCC complicating liver
cirrhosis, portal hypertension, and hypersplenism. Gelfoam sponge was used as the embolic material for PSE and limited to
100–150 pieces.
Results More than 50% of splenic parenchyma was infarcted in 27 patients. Leukopenia and thrombocytopenia were corrected by PSE in
25 of 27 patients with hypersplenism. In 26 patients with esophageal varices, including 5 patients with bleeding, no rebleeding
occurred during a 6–17 month follow-up. Hypersplenism was not corrected in 2 of 3 patients whose infarcted splenic parenchyma
was less than 50%. No splenic abscesses or other severe complications were observed. Of the 30 patients treated, 19 are still
alive after 1 year.
Conclusions THAE combined with PSE is a safe and effective measure for patients with HCC. 相似文献
110.
母体钙代谢与补钙对妊娠的影响 总被引:1,自引:0,他引:1
妊娠期缺钙严重影响母婴的安全健康 ,其原因是由于妊娠期母体钙代谢发生变化 ,使母体血清游离钙离子浓度降低 ,血清铅浓度增高。有关研究表明 ,母体缺钙导致血铅竞争性过高 ,使胎儿身长、体重均小于胎龄儿 ,胎儿宫内发育迟缓的发生率增高 ,甚至发生早产、死胎等。同时发现血清钙离子可能对内源性一氧化氮合成释放起调节作用 ,而内皮素是最强的缩血管物质之一 ,母体补钙可调节一氧化氮与内皮素的平衡 ,从而降低妊高征的发生率。因此孕期补充钙剂是非常重要的。 相似文献