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991.
992.
为探讨脂质过氧化损伤能否诱导血管内皮细胞表达细胞间粘附分子 1,用胰酶消化法分离人脐静脉内皮细胞进行原代培养 ,内皮细胞用不同浓度联胺作用相同时间或同一浓度联胺作用不同时间 ,使之发生脂质过氧化损伤 ,逆转录聚合酶链反应检测内皮细胞细胞间粘附分子 1mRNA表达 ,细胞酶链免疫吸附实验测定内皮细胞细胞间粘附分子 1蛋白表达。逆转录聚合酶链反应结果发现 ,不同浓度联胺 (1μmol L、5 μmol L和 10 μmol L)作用 8h ,内皮细胞细胞间粘附分子 1对 β actin吸光度比值依次为 0 .5 35、0 .90 8和 1.186 ,分别是对照组 (0 .185 )的 2 .89倍、4 .91倍和 6 .4 1倍 ;而同一浓度联胺 (5 μmol L)作用 4h和 2 4h ,吸光度比值依次为 0 .5 98和 1.2 92 ,分别是对照组 (0 .185 )的 3.2 3倍和 6 .98倍。细胞酶链免疫吸附实验结果发现 ,经 1μmol L、5 μmol L和 10 μmol L联胺作用 4h后 ,内皮细胞细胞间粘附分子 1蛋白表达的吸光度值依次为 0 .1387、0 .1775和 0 .2 32 6 ,分别是对照组 (0 .10 35 )的 1.34倍、1.71倍和 2 .2 5倍 (P <0 .0 1)。结果表明 ,联胺诱导的内皮细胞细胞间粘附分子 1的表达在一定作用时间和浓度范围内呈时间和剂量依赖性。提示联胺诱导的脂质过氧化损伤可能上调细胞间粘附分子 1mRNA和 相似文献
993.
Amino-terminal protein-protein interaction motif (POZ-domain) is responsible for activities of the promyelocytic leukemia zinc finger-retinoic acid receptor-alpha fusion protein. 总被引:16,自引:1,他引:16
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S Dong J Zhu A Reid P Strutt F Guidez H J Zhong Z Y Wang J Licht S Waxman C Chomienne et al. 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(8):3624-3629
Promyelocytic leukemia zinc finger-retinoic acid receptor a (PLZF-RARalpha), a fusion receptor generated as a result of a variant t(11;17) chromosomal translocation that occurs in a small subset of acute promyelocytic leukemia (APL) patients, has been shown to display a dominant-negative effect against the wild-type RARalpha/retinoid X receptor alpha (RXRalpha). We now show that its N-terminal region (called the POZ-domain), which mediates protein-protein interaction as well as specific nuclear localization of the wild-type PLZF and chimeric PLZF-RARalpha proteins, is primarily responsible for this activity. To further investigate the mechanisms of PLZF-RARalpha action, we have also studied its ligand-receptor, protein-protein, and protein-DNA interaction properties and compared them with those of the promyelocytic leukemia gene (PML)-RARalpha, which is expressed in the majority of APLs as a result of t(15;17) translocation. PLZF-RARalpha and PML-RARalpha have essentially the same ligand-binding affinities and can bind in vitro to retinoic acid response elements (RAREs) as homodimers or heterodimers with RXRalpha. PLZF-RARalpha homodimerization and heterodimerization with RXRalpha were primarily mediated by the POZ-domain and RARalpha sequence, respectively. Despite having identical RARalpha sequences, PLZF-RARalpha and PML-RARalpha homodimers recognized with different affinities distinct RAREs. Furthermore, PLZF-RARalpha could heterodimerize in vitro with the wild-type PLZF, suggesting that it may play a role in leukemogenesis by antagonizing actions of not only the retinoid receptors but also the wild-type PLZF and possibly other POZ-domain-containing regulators. These different protein-protein interactions and the target gene specificities of PLZF-RARalpha and PML-RARalpha may underlie, at least in part, the apparent resistance of APL with t(11;17) to differentiation effects of all-trans-retinoic acid. 相似文献
994.
目的:探讨血清亲环素A(Cy PA)的水平与新疆维吾尔族原发性高血压患者(EH)的相关性及与血压之间的关系。方法:选取新疆维吾尔族原发性高血压患者60例及血压正常对照组50例,检测各组的血压、体质指数、血脂等指标,采用酶联免疫吸附法(ELISA)检测各组血清Cy PA的浓度,并分析各指标的相关性。结果:原发性高血压组血清Cy PA的水平显著高于血压正常对照组(P<0.01);原发性高血压患者血清Cy PA水平与收缩压、舒张压存在显著正相关(r=0.497,P<0.01;r=0.324,P<0.05)。结论 :血清Cy PA在新疆维吾尔族原发性高血压患者升高,并与收缩压、舒张压存在一定的相关性。 相似文献
995.
目的:分析椎动脉供血不足的各种MRI征象,探讨其临床价值。材料与方法:收集临床拟诊椎动脉供血不足而行MRI检查的患者86例,进行MRI检查,对其MRI及CEMRA重建图像进行分析,对椎动脉的MRA评价主要包括其血管形态的观察以及周围组织结构改变。结果:椎动脉可见多段发病或多种病变形态共存的特点,椎动脉形态异常主要为先天发育畸形,包括管腔纤细,双侧椎动脉变细,单侧椎动脉变细以及椎动脉走行变异。血管局部狭窄,包括椎动脉起始段狭窄;颈椎段狭窄,包括椎间盘压迫、钩突关节增生压迫、横突孔增生;椎动脉颅内段扭曲狭窄等。结论:MRI尤其是MRA技术可以简便、直观显示椎动脉以及全面多方位观察它的形态,在一定程度上能够为临床准确诊断椎动脉供血不足提供直接证据。 相似文献
996.
Rong Hu Min Lin Jun Ye Bao-Ping Zheng Li-Xia Jiang Juan-Juan Zhu Xiao-Hong Chen Mi Lai Tian-Yu Zhong 《International journal of clinical and experimental pathology》2015,8(11):15013-15018
In southern China, glucose-6-phosphate dehydrogenase (G6PD) deficiency is a significant health problem, and the incidence ranged from 0.5 to 4.08% in different Chinese population. The aims of this study are to investigate the molecular epidemiological characteristic of the G6PD gene among Chinese Hakka in southern Jiangxi province. 2331 unrelated subjects were screened for G6PD deficiency by a fluorescent test. DNA from deficient individuals was analyzed by a gene chip analysis for thirteen common Chinese G6PD mutations. In total, 3.60% (82/2331; 95% CI 2.77-4.27) of the sample were found to be G6PD-deficient. Eight mutations were found from 80 samples. However, mutation(s) for the two remaining samples were unknown. The most common mutations were G6PD Canton (1376 G>T) and G6PD Kaiping (1388 G>A), and the following mutations were 1311 polymorphism (1311 C>T), G6PD Gaohe (95 A>G), G6PD Chinese-5 (1024 C>T), G6PD Maewo (1360 C>T), Shunde (592 C>T), G6PD Viangchan (871 G>A) and Chinese-3 (493 A>G). This is the first report of G6PD deficiency among Chinese Hakka population in Jiangxi province. 相似文献
997.
998.
目的 应用CBCT技术,分析全口义齿再修复时颞下颌关节盘的间隙变化,以确定患者一次垂直距离恢复的最大值,为临床提供依据。方法 选择全口义齿使用超过5年的需要再修复患者30例,按常规制作新的全口义齿,根据患者全口义齿垂直距离恢复情况分为3组, A组为恢复1.0mm~2.5mm, B组为恢复2.5mm~5.0mm, C组为恢复大于5.0mm。通过自身对照,观察新旧全口义齿垂直距离改变,并在CBCT下记录颞下颌关节盘间隙变化,结合临床患者资料,分析垂直距离改变和颞下颌关节盘间隙的关系,明确垂直距离恢复程度对关节的影响。结果 A组关节盘上、前、后变化在(0.10~0.50)±0.20mm区间,患者新全口义齿一周内可适应; B组关节盘上、前、后变化在(0.50~1.11)±0.32mm区间,患者新全口义齿适应时间相对长; C组关节盘上、前、后变化在>(1.50±0.50) mm区间,患者新全口义齿失败可能性明显增加。结论 全口义齿再修复时建议一次性恢复垂直距离高度以不超过2.5mm为宜,最大值在5mm以内,以减少全口义齿修复失败和诱导颞下颌关节疾病的可能,大于5mm以上明显存在失败风险。 相似文献
999.
Chen Wei Liu Wen-En Li Yang-Ming Luo Shan Zhong Yi-Ming 《Archives of Medical Science》2015,11(5):927-936
Introduction
Clostridium difficile infection (CDI) remains a diagnostic challenge for clinicians. More recently, loop-mediated isothermal amplification (LAMP) has become readily available for the diagnosis of CDI, and many studies have investigated the usefulness of LAMP for rapid and accurate diagnosis of CDI. However, the overall diagnostic accuracy of LAMP for CDI remains unclear. In this meta-analysis, our aim was to establish the overall diagnostic accuracy of LAMP in detection of Clostridium difficile (CD) in stool samples.Material and methods
A search was done in PubMed, MEDLINE, EMBASE and Cochrane Library databases up to February 2014 to identify published studies that evaluated the diagnostic role of LAMP for CD. Methodological quality was assessed according to the quality assessment for studies of diagnostic accuracy (QUADAS) instrument. The sensitivities (SEN), specificities (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR) and diagnostic odds ratio (DOR) were pooled statistically using random effects models. Statistical analysis was performed by employing Meta-Disc 1.4 software. Summary receiver operating characteristic (SROC) curves were used to summarize overall test performance. Funnel plots were used to test the potential publication bias.Result
A total of 9 studies met inclusion criteria for the present meta-analysis. The pooled SEN and SPE for diagnosing CD were 0.93 (95% CI: 0.91–0.95) and 0.98 (95% CI: 0.98–0.99), respectively. The PLR was 47.72 (95% CI: 15.10–150.82), NLR was 0.07 (95% CI: 0.04–0.14) and DOR was 745.19 (95% CI: 229.30−2421.72). The area under the ROC was 0.98. Meta-regression indicated that the total number of samples was a source of heterogeneity for LAMP in detection of CD. The funnel plots suggested no publication bias.Conclusions
The LAMP meets the minimum desirable characteristics of a diagnostic test of SEN, SPE and other measures of accuracy in the diagnosis of CD, and it is suitable as a rapid, effective and reliable stand-alone diagnostic test for diagnosis of CDI, potentially decreasing morbidity and nosocomial spread of CD. 相似文献1000.
Li-Chang Zhong Feng Lu Fang Ma Hui-Xiong Xu Dan-Dan Li Le-Hang Guo Li-Ping Sun 《International journal of clinical and experimental pathology》2015,8(3):3155-3159
Purpose: The management criterion of thyroid nodules is to evaluate the risk of malignancy, based on cytological examinations. Ultrasound-guided fine-needle aspiration biopsy (US-FNAB) has a highly diagnostic value for thyroid nodules. The aim of this study was to compare the efficacy of US-FNAB for thyroid nodules with different sizes. Material and methods: From August 2013 to November 2013, 344patients with thyroid nodules who had undergone US-FNAB were divided into three groups, according to the largest diameter of their nodules (group A, ≤ 5.0 mm; group B, 5.1-10.0 mm; group C, > 10.0 mm). All the nodules were subsequently verified by histology or follow-up findings. The accuracy, sensitivity, specificity, positive predictive value, negative predictive value of aspiration cytology in each group was compared. Results: Among 344 thyroid nodules diagnosed by cytology, the cytology was classified as nondiagnostic or unsatisfactory for 53 (15.4%) lesions, benign for 144 (41.9%) lesions, atypia of undetermined significance or follicular lesion of undetermined significance for 20 (5.8%) lesions, follicular neoplasm or suspicious for a follicular neoplasm for 26 (7.6%) lesions, suspicious for malignancy for 36 (10.5%) lesions, malignant for 65 (18.9%) lesions. There were 243 benign and 101 malignant nodules confirmed by the pathological or follow-up ultrasound. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were confirmed to be 87.5% (14/16), 92.5% (37/40), 91% (51/56), 82.3% (14/17), and 94.8% (37/39) in group A; 92.3% (36/39), 96.9% (94/97), 95.5% (130/136), 92.3% (36/39), and 96.9% (94/97) in group B; and 91.3% (42/46), 93.4% (99/106), 92.7% (141/152) 85.7% (42/49), and 96.1% (99/103), in group C. There were no statistical differences in accuracy, sensitivity, specificity, false positive accuracy, false negative rate of fine needle aspiration of thyroid nodules with different sizes (P > 0.05). Conclusion: US-FNAB has similar diagnostic efficacy to thyroid nodules with different sizes. 相似文献