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121.
目的:探究首发缺血性脑卒中患者血清同型半胱氨酸(Hcy)和红细胞生成素(EPO)水平的变化和意义。方法:于2013年10月-2015年4月我科收治的首发缺血性脑卒中患者中随机选取98例作为观察组,另选取同期健康体检者98例作为对照组,检测患者的血小板、血浆纤维蛋白原(Fib)以及血白细胞水平,比较两组血清Hcy、EPO、血小板、Fib及血白细胞水平,使用Logistic回归分析法评价缺血性脑卒中病发的危险因素,采用Spearman法对血清Hcy与EPO间相关性进行分析。结果:观察组的Hcy(23.52±12.15)m IU/L与EPO(34.61±11.25)m IU/L水平显著高于对照组的(10.57±2.18)m IU/L、(17.54±5.83)m IU/L;观察组血小板、血浆纤维蛋白原(fibrinogen,Fib)及血白细胞水平均高于对照组;差异均有统计学意义(均P0.05)。经Logistic回归分析法分析可知,Hcy为缺血性脑卒中病发的独立因素,经Spearman相关性分析显示,首发缺血性脑卒中患者EPO水平与Hcy呈正相关。结论:缺血性脑卒中病发与血清Hcy和EPO水平升高密切相关,且Hcy是导致缺血性脑卒中病发的高危因素。 相似文献
122.
目的:探讨早发冠心病(PCAD)患者的危险因素及冠脉病变特点。方法:收集2014年8月至2015年2月北京安贞医院急诊科行冠状动脉造影的1000例患者为研究对象,根据冠状动脉造影结果和临床资料分为早发冠心病(PCAD)组(男55岁,女65岁,n=340)、晚发冠心病组(n=300)和对照组(非冠心病者,n=360)。对三组患者的临床资料进行统计学分析,采用logistic回归分析PCAD患者的危险因素,并比较PCAD组与晚发冠心病组的冠状动脉病变特点。结果:Logistic回归分析结果提示:吸烟、早发冠心病家族史、高血压病及2型糖尿病是PCAD的独立危险因素(P0.001)。PCAD组单支病变比例显著高于晚发冠心病组(P0.05);回旋支、右冠状动脉病变比例低于晚发冠心病组(P0.05)。结论:吸烟、早发冠心病家族史、高血压病及2型糖尿病是PCAD的独立危险因素。早发冠心病患者冠脉病变主要累及前降支,单支病变多于晚发冠心病患者。 相似文献
123.
Time and space in the middle paleolithic: Spatial structure and occupation dynamics of seven open‐air sites 下载免费PDF全文
Amy E. Clark 《Evolutionary anthropology》2016,25(3):153-163
The spatial structure of archeological sites can help reconstruct the settlement dynamics of hunter‐gatherers by providing information on the number and length of occupations. This study seeks to access this information through a comparison of seven sites. These sites are open‐air and were all excavated over large spatial areas, up to 2,000 m2, and are therefore ideal for spatial analysis, which was done using two complementary methods, lithic refitting and density zones. Both methods were assessed statistically using confidence intervals. The statistically significant results from each site were then compiled to evaluate trends that occur across the seven sites. These results were used to assess the “spatial consistency” of each assemblage and, through that, the number and duration of occupations. This study demonstrates that spatial analysis can be a powerful tool in research on occupation dynamics and can help disentangle the many occupations that often make up an archeological assemblage. 相似文献
124.
Lin Chen Lingjun Kong Xinbing Wei Yimeng Wang Bing Wang Xiumei Zhang Jinpeng Sun Huiqing Liu 《Journal of cellular and molecular medicine》2019,23(5):3325-3335
We previously reported that nucleotide‐binding oligomerization domain‐containing protein (NOD) 2 was involved in the inflammatory responses to cerebral ischaemia/reperfusion (I/R) insult. However, the mechanism by which NOD2 participates in brain ischaemic injury and the regulation of NOD2 in the process are still obscure. Increased β‐arrestin 2 (ARRB2) expression was observed in microglia following cerebral I/R in wild‐type mice besides the up‐regulation of NOD2 and TRAF6. Stimulation of NOD2 by muramyl dipeptide (MDP) in BV2 cells induced the activation of NF‐κB by the phosphorylation of p65 subunit and the degradation of IκBα. Meanwhile, the protein level of Cyclooxygenase‐2 (COX‐2), the protein expression and activity of MMP‐9 were significantly increased in BV2 cells after administration of MDP. Furthermore, overexpression of ARRB2 significantly suppressed the inflammation induced by MDP, silence of ARRB2 significantly enhanced the inflammation induced by MDP in BV2 cells. In addition, we observed endogenous interaction of TRAF6 and ARRB2 after stimulation of MDP or cerebral I/R insult, indicating ARRB2 negatively regulates NOD2‐triggered inflammatory signalling pathway by associating with TRAF6 in microglia after cerebral I/R injury. Finally, the in vivo study clearly confirmed that ARRB2 negatively regulated NOD2‐induced inflammatory response, as ARRB2 deficiency exacerbated stroke outcomes and aggravated the NF‐κB signalling pathway induced by NOD2 stimulation after cerebral I/R injury. These findings revealed ARRB2 negatively regulated NOD2 signalling pathway through the association with TRAF6 in cerebral I/R injury. 相似文献
125.
Zahra Rahmani Chang‐Jun Kim Mostafa Ghafouri Moghaddam Ehsan Rakhshani 《Entomological Research》2019,49(9):409-415
Occurrence of the family Ismaridae Thomson is recorded for the first time from Iran, represented by a single species, Ismarus rugulosus Förster, 1850. A series of diagnostic characters and morphometric ratios for this species is presented, as well as a distribution map throughout the Holarctic region. 相似文献
126.
目的探索一种从人中鼻甲分离培养嗅鞘细胞的方法并鉴定所获得的细胞。
方法通过手术获取人中鼻甲黏膜组织,随后进行两步消化并剥离黏膜上皮组织,得到体积较小的组织块,再进行组织块原代(传代)培养并加压筛选,最终得到双极或多极样细胞并对获得的细胞进行免疫荧光鉴定。上皮样细胞比例、S100β和p75阳性细胞比例用
±s表示,组间比较采用独立样本t检验。
结果将不剥离上皮层与剥离上皮层培养的原代细胞中上皮样细胞的比例进行对比,发现上皮层组上皮样细胞比例为(92.23±3.93)%高于剥离上皮层组上皮样细胞的比例(77.63±2.97)%,差异具有统计学意义(t = 5.129,P = 0.007)。采用剥离上皮层法培养原代细胞,经过加压筛选的细胞呈现双极或多极样,符合嗅鞘细胞形态学特点。免疫荧光染色发现,S100β阳性细胞占总细胞量的(8.1±1.7)%,而p75阳性细胞占总细胞量的5%以下,达到国内外研究同等水平。
结论通过使用两步消化法和加压筛选联合的方法从人中鼻甲粘膜组织中成功获得了人中鼻甲嗅鞘细胞,相比较传统方法,细胞分离培养周期明显缩短。 相似文献
127.
128.
张慧敏 《现代生物医学进展》2007,7(5):682-685,F0003
目的:在分子水平探讨并阐明脑缺血再灌注脑损伤的炎性机理和针刺对局灶性脑缺血模型脑微血管内皮细胞功能的动态影响。方法:采用大脑中动脉线栓阻塞法建立大鼠局灶性脑缺血模型;用免疫组化SABC法检测脑缺血后治疗1d、3d、5d、10d细胞间粘附分子-1的表达。结果:针刺不同疗程治疗各组大鼠在治疗前后的神经症状行为评定分析有显著性差异(p<0.05);模型组ICAM-1脑缺血后ID即出现表达,5D达到表达高峰,各个时间点相比具有显著的统计学意义(P<0.01)。结论:头针对脑缺血状态下微血管内皮细胞功能的全方位和多层面良性调节机制,并且这种良性机制随着干预时间的选择(早期/6 d)和疗程的适度延长(5天以上),具有明显的累加蓄积效应。 相似文献
129.
《Geobios》2019
Following a recent chronostratigraphic revision of 17 fossiliferous sites hosting assemblages constituting local faunas of the Aurelian Mammal Age for peninsular Italy, we provide a re-structured biochronological framework and discuss the current validity and significance of the middle Pleistocene Faunal Units (FU) for this region. Contrasting with the previous model of a wide faunal renewal during Marine Isotope Stage (MIS) 9 (∼ 330 ka), the First Occurrences (FO) of several species of the Torre in Pietra FU are significantly backdated and referred to the Fontana Ranuccio FU (530–400 ka). We show that the faunal renewal was more gradual and occurred earlier than previously assumed. Many taxa that are typical of the late Pleistocene register their FO in the Fontana Ranuccio FU, latest Galerian, which is characterized by the almost total disappearance of Villafranchian taxa and by the persistence of typical Galerian taxa such as Dama clactoniana, Bison schoetensacki and Ursus deningeri, and by the FO of Stephanorhinus kirchbergensis, S. hemitoechus, Hippopotamus amphibius, Cervus elaphus eostepahnoceros, Ursus spelaeus, Canis lupus, and Vulpes vulpes. The next Torre in Pietra FU is characterized only by the FO of Megaloceros giganteus and Mustela putorius. However, we observe that MIS 9 marks the actual moment when the faunal assemblages of this region are represented only by those taxa characterizing the late middle Pleistocene and late Pleistocene. For this reason, we propose to still consider the Torre in Pietra (lower levels) local fauna as a conventional boundary for the Galerian-Aurelian transition. Finally, we remark that the strong faunal renewal in MIS 13, with five FOs, coincides with the temperate climatic conditions due to the absence of marked glacial periods that could have favored the FO and the subsequent spread of these taxa. 相似文献
130.
Peripheral artery disease (PAD) is associated with an increased risk of adverse cardiovascular events, impaired lower extremity blood flow and microvascular perfusion abnormalities in the calf muscles which can be determined with contrast-enhanced magnetic resonance imaging (CE-MRI). We developed a computational model of the microvascular perfusion in the calf muscles. We included 20 patients (10 PAD, 10 controls) and utilized the geometry, mean signal intensity and arterial input functions from CE-MRI calf muscle perfusion scans. The model included the microvascular pressure (pv), outflow filtration coefficient (OFC), transfer rate constant (kt), porosity (φ), and the interstitial permeability (Ktissue). Parameters were fitted and the simulations were compared across PAD patients and controls. Intra-observer reproducibility of the simulated mean signal intensities was excellent (intraclass correlation coefficients >0.995). kt and Ktissue were higher in PAD patients compared with controls (4.72 interquartile range (IQR) 3.33, 5.56 vs. 2.47 IQR 2.10, 2.85; p = 0.003; and 3.68 IQR 3.18, 4.41 vs. 1.81 IQR 1.81, 1.81; p < 0.001). Conversely, porosity (φ) was lower in PAD patients compared with controls (0.52 IQR 0.49, 0.54 vs. 0.61 IQR 0.58, 0.64; p = 0.016). Porosity (φ) was correlated with the ankle brachial index (r = 0.64, p = 0.011). The proposed computational microvascular model is robust and reproducible, and essential model parameters differ significantly between PAD patients and controls. 相似文献