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91.
目的:研究冠状动脉严重狭窄稳定型心绞痛(Stable angina pectoris, SPA)患者循环内皮祖细胞(endothelial progenitor cells, EPCs)及基质细胞衍生因子(SDF)-1-alpha与冠状动脉侧支循环(CCC)形成的相关性,以期为治疗冠心病提供新的思路。方法:选择 2012 年8 月到2014 年12月在我院就诊的88 例冠状动脉严重狭窄的稳定型心绞痛患者(CCC 良好40 例、不良48 例),均采集 外周血测定EPC 数量、体外生成血管能力,并用ELISA 法检测其血浆SDF-1alpha 水平,采用直线相关和Pearson 检验分析CCC良好 与不良者各指标间及与CCC 分级的相关性;将所有入选病例随机分为6 组,并分离外周血单个核细胞并分别加入不同的培养 液,培养7 天后体外测定EPCs 数量以及生成血管的能力,并通过ELISA 法检测培养液上清中VEGF 的蛋白水平。结果:CCC 不 良组EPCs 数量、体外生成血管能力及SDF-1-alpha水平均明显低于CCC 良好组(P<0.05)。体外生成血管能力、循环EPCs 数量以及 SDF-1alpha水平均与CCC分级呈现显著的正相关性(r =0.72、0.67、0.79,均P<0.05);循环EPCs 数量、SDF-1alpha水平以及体外生成血 管能力亦均呈现显著正相关性(r =0.78、0.62,均P<0.05)。与PBS、SDF-1alpha+ AMD3100 及SDF-1alpha+ KI8751 干预物质比较,SDF-1琢 能够呈剂量依赖性的明显提高EPCs 数量、增强其体外生成血管的能力及VEGF水平(P<0.05)。结论:冠状动脉严重狭窄稳定型 心绞痛患者循环EPCs及SDF-1琢与CCC 形成有关,VEGF可能参与该过程。  相似文献   
92.
目的:对比分析肺癌患者和肺部非癌性病变肺动脉和主支气管动脉CTA特点。方法:回顾性统计分析82例行高度怀疑肺癌患者的肺部CTA,经病理证实肺癌54例,肺结核球28例,同时选择对照组22例。对比分析肺动脉(Pulmonary artery,PA)内径、主支气管动脉(Bronchial artery,BA)显影率和及其各级分支显影率。结果:肺癌组、肺结核球组和对照组左主支气管动脉显影率分别为83.3%、77.7%和72.7%。右主支气管动脉显影率87.0%、83.3%和68.1%。肺癌组左右主支气管动脉清晰显影率高于肺结核球组和对照组,差异有统计学意义(P0.05)。左右两侧肺癌组PA内径明显大于结核球和对照组,差异有统计学意义(P0.05)。左右侧肺癌组PA显影分级明显高于结核球和对照组,差异有统计学意义(P0.05)。左右双侧PA主干内径差异无统计学意义(P0.05)。结论:肺部癌性病灶动脉供血增加,肺动脉和支气管动脉CTA能够显示肺癌病灶供血情况,可用于临床辅助鉴别诊断影像学不能确诊的肺部病变。  相似文献   
93.
目的:从分子遗传学角度分析血管紧张素转换酶(ACE)基因I/D多态与中国北方汉族人群中冠心病发病的相关关系。方法:本研究收集在沈阳军区总医院心内科住院的行冠脉造影检查的病例为研究对象,冠脉动脉照影检查显示冠状动脉主支狭窄程度大于等于70%的入选为冠心病组,冠状动脉照影检查显示冠状动脉主支狭窄程度小于20%的为对照组,共入选568名冠心病患者以及性别与年龄相匹配的529名对照个体为研究对象,利用测序的方法分析检测血管紧张素转换酶(ACE)基因I/D多态在冠心病组与对照组中的频率分布情况。结果:血管紧张素转换酶(ACE)基因I/D多态基因型频率符合Hardy-Weinberg定律。血管紧张素转换酶(ACE)基因I/D多态(II型,ID型和DD型)在我们入选的568例冠心病组分布频率分别为50.3%,30.3%和19.4%,而在我们入选的524例对照组中的分布频率为57.7%,31.2%和11.1%,研究发现血管紧张素转换酶(ACE)基因I/D多态可能是中国北方汉族人群冠心病发病的独立危险因素(P0.05);利用多元回归分析发现,在调整了冠心病的其他危险因素后,血管紧张素转换酶(ACE)基因I/D多态的变化仍然是中国北方汉族人群冠心病发病一个独立危险因素,可以预测中国北方汉族人群冠心病的发生。结论:在中国北方汉族人群中,血管紧张素转换酶(ACE)基因I/D多态可能是冠心病发病的独立危险因素,在临床上可以早期预判冠心病的发生。  相似文献   
94.
The use of Micro-Computed Tomography (MicroCT) for in vivo studies of small animals as models of human disease has risen tremendously due to the fact that MicroCT provides quantitative high-resolution three-dimensional (3D) anatomical data non-destructively and longitudinally. Most importantly, with the development of a novel preclinical iodinated contrast agent called eXIA160, functional and metabolic assessment of the heart became possible. However, prior to the advent of commercial MicroCT scanners equipped with X-ray flat-panel detector technology and easy-to-use cardio-respiratory gating, preclinical studies of cardiovascular disease (CVD) in small animals required a MicroCT technologist with advanced skills, and thus were impractical for widespread implementation. The goal of this work is to provide a practical guide to the use of the high-speed Quantum FX MicroCT system for comprehensive determination of myocardial global and regional function along with assessment of myocardial perfusion, metabolism and viability in healthy mice and in a cardiac ischemia mouse model induced by permanent occlusion of the left anterior descending coronary artery (LAD).  相似文献   
95.
Diabetes mellitus (DM) is an important risk factor for adverse outcomes of coronary artery bypass grafting. The bypass grafts harvested from patients with DM tend to go into spasm after their implantation into the coronary circulation. To clarify the contribution of 5-hydroxytriptamine (5-HT) and angiotensin II (AngII) in the bypass graft spasm, we examined the contractile reactivity to 5-HT or AngII of isolated human endothelium-denuded saphenous vein (SV) harvested from DM and non-DM patients. The 5-HT-induced constriction of the SV was significantly augmented in the DM group than in the non-DM group, which is similar to our previous report. AngII-induced constriction of the SV was also significantly augmented in the DM group than the non-DM group. Especially in the non-DM group, the AngII-induced maximal vasoconstriction was markedly lower than the 5-HT-induced one. Meanwhile, the increasing rates of AngII-induced vasoconstriction in the DM group to the non-DM group were significantly greater than those of 5-HT-induced vasoconstriction. These results indicate that 5-HT is a potent inducer of SV graft spasm in both DM and non-DM patients, while AngII is a potent inducer of SV graft spasm only in patients with DM. Furthermore, the protein level of AngII AT1 receptor (AT1R), but not the protein level of 5-HT2A receptor, in the membrane fraction of the SV smooth muscle cells of DM patients was significantly increased as compared with that of the non-DM patients. These results suggest that the mechanism for hyperreactivity to AngII in the SV from DM patients is due to, at least in part, the increase in the amount of AT1R on membrane of the SV smooth muscle cells.  相似文献   
96.
《Cryobiology》2016,73(3):210-215
Several methods are currently available for selection when conducting sperm cryopreservation, however, these methods might cause different degrees of damage on sperm DNA. The aim of the this study is to compare the effects of storage at −80 °C (in ultra-low temperature refrigerator) and at −196 °C (in liquid nitrogen) on sperm DNA damage, thus to provide a reference for choosing the right method according to different aims. We randomly collected 28 semen samples from college students of Chongqing city. The samples stored at −80 °C were neat semen samples and the samples stored at −196 °C were mixed with additional cryoprotectants. Each sample was subjected to two freezing-thawing cycles, and the sperm DNA damage levels of fresh and thawed samples were measured by single cell gel electrophoresis (SCGE) and sperm chromatin structure assay (SCSA). Both SCGE and SCSA assays showed cryopreservation induced significant damage to sperm DNA. However, storage at −196 °C lead to more severe damage to sperm DNA than storage at −80 °C measured by SCSA. Sperm DNA damage increased simultaneously with the higher frequency of freezing-thawing cycles. We concluded that storage of neat semen samples at −80 °C had milder damage to sperm DNA than storage at −196 °C mixed with cryoprotectants. To avoid additional sperm DNA damage, repeated freezing and thawing should be prevented.  相似文献   
97.
目的:探讨子宫动脉化疗栓塞术治疗胎盘植入的临床疗效及预后。方法:以胎盘植入患者61例为研究对象,按治疗方式不同分为保守治疗组31例和化疗栓塞组30例。保守治疗组仅单纯口服米非司酮治疗,而化疗栓塞组采用子宫动脉化疗栓塞术进行治疗。比较两组患者的临床疗效、手术时间、出血量、输血量、住院时间、胎盘排出和月经复潮时间,术后并发症的发生情况,并随访术后1年患者的月经情况和妊娠情况。结果:经子宫动脉化疗栓塞术后29例成功止血,有1例未能止血而行子宫切除术。栓塞术后未出现器官局部缺血坏死、神经损伤等严重并发症,发热、下腹痛为常见并发症。而保守治疗组的31例患者中,因治疗失败导致切除子宫的7例,仅24例有效保留子宫,成功率仅77.4%,严重影响患者以后的生育能力。6例发生宫腔感染,4例发生宫腔粘连。子宫动脉化疗栓塞组β-HCG恢复正常时间、输血量、胎盘完全清除时间、月经异常的发生情况均优于保守治疗组,差异有统计学意义(P0.05)。对子宫动脉化疗栓塞术组患者进行为期1年的随访,14例患者在术后1个月后有胎盘组织自阴道排出,有11例患者2个月后发现胎盘残留,予以清宫术,除3例失访病例,其余患者在随访时间内恢复正常月经,并有2例再次妊娠者。结论:采用子宫动脉化疗栓塞术治疗胎盘植入,其术前准备时间和手术时间均短,出血控制迅速且并发症少,有助于保留患者的子宫,提高患者的生活质量。  相似文献   
98.
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   
99.
BackgroundCardiovascular disease has become a major health problem, and it has been associated with both environmental and genetic factors. Studies have shown that the Mediterranean Diet (MeDiet), or its components such as nuts and olive oil, may be strongly associated with the improvement of cardiovascular risk factors in specific populations. The purpose of the GENUTRI study is to investigate the interaction of genetics with cardiovascular risk factors in a non-Mediterranean population with coronary artery disease (CAD) according to three different diets: rich in pecan nuts, in extra-virgin olive oil or a control diet.Methods/designThe GENUTRI study is a single-center, randomized, open-label, parallel-group, 12-week pragmatic clinical trial conducted in patients aged 40 to 80 years and diagnosed with CAD. A standardized questionnaire will be applied to data collection and a blood sample will be obtained for lipid, glycemic and inflammatory profile evaluation. Polymorphisms in the CD36 and STAT3 genes will be detected using the TaqMan® SNP Genotyping Assay. Patients will be allocated in three groups: group 1: 30 g/day of pecan nuts; group 2: 30 ml/day of olive oil; and group 3: control diet. The primary outcome will consist of changes in LDL-cholesterol (in mg/dl) after 12 weeks of intervention.DiscussionStudies have shown the beneficial effects of diets rich in nuts and olive oil mainly in the Mediterranean population. GENUTRI is a clinical trial focusing on the effects of nuts or olive oil supplementation in Brazilian individuals. Additionally, we will try to demonstrate that genetic polymorphisms linked to cardiovascular disease may modulate the effects of different diets on biochemical and inflammatory markers among these subjects.

Trial registration

ClinicalTrials.gov Identifier: NCT02202265 (registered on 18 July 2014: first version).  相似文献   
100.
目的:探讨正肝化症方联合隔姜灸对原发性肝癌(PHC)行经肝动脉化疗栓塞术(TACE)患者肝功能和免疫功能的影响。方法:选取2015年2月~2018年11月期间广东省第二人民医院收治的PHC患者121例,根据数表法将患者随机分为对照组(n=60)和研究组(n=61),其中对照组予以TACE治疗,研究组在对照组基础上予以正肝化症方联合隔姜灸治疗,比较两组患者临床疗效、生活质量及肝功能、免疫功能指标水平,记录两组治疗期间不良反应发生情况。结果:研究组治疗后临床总有效率为75.41%(46/61),高于对照组患者的56.67%(34/60)(P0.05)。两组患者治疗后谷氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、总胆红素(TBIL)均较治疗前降低,且研究组低于对照组(P0.05)。两组患者治疗后CD4~+、CD4~+/CD8~+均较治疗前升高,且研究组高于对照组(P0.05);CD8~+较治疗前降低,且研究组低于对照组(P0.05)。两组患者治疗后健康调查简表(SF-36)评分较治疗前升高,且研究组高于对照组(P0.05)。研究组不良反应总发生率低于对照组(P0.05)。结论:正肝化症方联合隔姜灸辅助TACE治疗PHC患者,疗效确切,可有效改善患者肝功能以及免疫功能,提高患者生活质量,减少不良反应发生率。  相似文献   
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