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排序方式: 共有986条查询结果,搜索用时 31 毫秒
1.
目的:研究心脏康复运动对冠脉支架植入术后患者血脂、血糖、体重指数及生活质量的影响。方法:对实施冠脉支架植入术的 146例患者进行比较分析,根据随机原则分为试验组76 例及对照组70 例。对照组患者给予常规的健康教育及冠心病二级预防指 导,给予定期随访。试验组患者在此基础上给予规律的康复运动指导。经过6 个月随访,比较两组患者血脂、HbA1C、体重指数及 生活质量情况。结果:试验组患者通过为期6 个月的规律的心脏康复运动指导,其血脂、HbA1C等冠心病危险因素控制情况优于 对照组,差异有统计学意义(P<0.05)。同时,6个月后,试验组康复运动六月后sF 量表各项评分与对照组同期比较,差异均有统计 学意义(P<0.05)。结论:规范的心脏康复运动指导能够有效改善冠脉支架植入术后患者血脂、血糖情况,提高患者生活质量。  相似文献   
2.
Control of plasma cholesterol levels is a major therapeutic strategy for management of coronary artery disease (CAD). Although reducing LDL cholesterol (LDL-c) levels decreases morbidity and mortality, this therapeutic intervention only translates into a 25–40% reduction in cardiovascular events. Epidemiological studies have shown that a high LDL-c level is not the only risk factor for CAD; low HDL cholesterol (HDL-c) is an independent risk factor for CAD. Apolipoprotein A-I (ApoA-I) is the major protein component of HDL-c that mediates reverse cholesterol transport from tissues to the liver for excretion. Therefore, increasing ApoA-I levels is an attractive strategy for HDL-c elevation. Using genome-wide siRNA screening, targets that regulate hepatocyte ApoA-I secretion were identified through transfection of 21,789 siRNAs into hepatocytes whereby cell supernatants were assayed for ApoA-I. Approximately 800 genes were identified and triaged using a convergence of information, including genetic associations with HDL-c levels, tissue-specific gene expression, druggability assessments, and pathway analysis. Fifty-nine genes were selected for reconfirmation; 40 genes were confirmed. Here we describe the siRNA screening strategy, assay implementation and validation, data triaging, and example genes of interest. The genes of interest include known and novel genes encoding secreted enzymes, proteases, G-protein-coupled receptors, metabolic enzymes, ion transporters, and proteins of unknown function. Repression of farnesyltransferase (FNTA) by siRNA and the enzyme inhibitor manumycin A caused elevation of ApoA-I secretion from hepatocytes and from transgenic mice expressing hApoA-I and cholesterol ester transfer protein transgenes. In total, this work underscores the power of functional genetic assessment to identify new therapeutic targets.  相似文献   
3.
We report a comparison of fibrinolytic variables between 10 Caucasians on a predominantly European diet and 10 Greenland Eskimos on a traditional Inuit diet containing a substantial amount of fish and sea animals. We studied the diurnal variation in tissue type plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI) antigens and activities during a 24-h period. Blood samples were taken every 4 h. The variations of the sinusoidal curves were evaluated by the Friedman χ2 test. t-PA and PAI-1 antigen in plasma fluctuated significantly during the 24 h (Eskimos p < 0.000007 and p < 0.0007; Caucasians p < 0.00003 and p < 0.02), with a peak in the early morning and a nadir in the afternoon. This also held true for PA1 activity (Eskimos p < 0.0008; Caucasians p < O.Ol), whereas t-PA activity showed an inverse but still significant pattern (Eskimos p < 0.006; Caucasians p < 0.0008). Amplitudes, areas underneath, and overall medians of the sinusoidal curves did not deviate between the two groups with respect to t-PA and PAL In contrast to the significant variation of t-PA and PAI, the plasma concentrations of fibrin degradation products (D-Dimer), a measure of effective fibrinolysis, remained constant during the 24 h, and the absolute differences between groups did not reach statistical significance. These findings suggest that circadian variation of fibrinolytic activators and inhibitors is a basic biologic phenomenon, which is not affected by life-style, dietary habits, or ethnic differences. Furthermore, the lack of diurnal variation in D-Dimer raises the question of whether there is a causal relationship between low morning activities of t-PA and the frequent onset of myocardial infarction at that time of day, as suggested by several authors.  相似文献   
4.
Summary Correlated physiological and electron-microscopic studies were made on the source of calcium activating the contractile system (activator calcium) in dog coronary artery smooth muscle fibers. The magnitude of contracture tension induced by 100 mM K+ was dependent on external Ca2+ concentration and reduced or eliminated by factors known to reduce the Ca2+ spike or ca2+ influx. Little or no mechanical response was elicited by treatments known to cause release of intracellularly stored calcium. These results indicated that the contractile system is mainly activated by the inward movement of extracellular calcium. In accordance with the physiological experiments, electron-opaque pyroantimonate precipitate containing calcium was found in the lumina of caveolae, but not in any intracellular structures close to the plasma membrane, when the relaxed fibers were fixed in a 1% osmium tetroxide solution containing 2% potassium pyroantimonate. If the contracted fibers were fixed in the same solution, the pyroantimonate precipitate was diffusely distributed in the myoplasm in the form of numerous particles, while the precipitate in the caveolar lumina was scarcely seen. These findings are discussed in connection with the regulation of intracellular Ca2+ concentration in dog coronary artery smooth muscle.  相似文献   
5.
1. The mechanisms utilised by the newborn quoll to move from the uterus to the teat within the pouch are unknown. The ability to sense gravity and odour have been suggested and it is possible that temperature may also assist the young in this migration.

2. An increasing temperature gradient was observed from the sinus at 28.98 °C increasing to 29.38 °C on the skin between the sinus and the pouch and further increasing to 30.96 °C within the pouch. This temperature gradient was not as apparent during lactation.

3. Hairs may also play an important role in allowing the newborn to leave the gelatinous material emanating from the uterus and travel to the pouch. The hairs form a tunnel between the sinus and the pouch and may assist the young in the moving from uterus to the pouch.  相似文献   

6.
目的探讨建立急性心功能不全动物模型的可行性。方法完全结扎犬前降支,进行快速右室起搏,使心输出量(CCO)较基础状态稳定地下降50%,分别测定基础及心输出量下降状态下的血压(AP)、血氧(SaO2)、平均右房压(mRAP)、平均肺毛压(mPCWP)、系统血管阻力(SVR)、心腔大小、左室射血分数(LVEF)、血浆肾素活性(PRA)、内皮素(ET)、尿量(UO)、血肌酐(Scr)、肌酐清除率(Ccr)。结果结扎LAD和快速右室起搏后,CCO较基础状态均稳定地下降50%,CCO降低后,AP、SaO2显著下降,mRAP、mPCWP、SVR显著升高;心脏各腔室明显扩大,LVEF显著降低;PRA、ET、Scr明显升高,UO、Ccr明显下降。结论结扎冠状动脉前降支及快速右心室起搏可成功制作急性心功能不全的动物模型。  相似文献   
7.

Aims

The aim of this study was to evaluate the combined contribution of 12 genetic variants to the risk of coronary heart disease (CHD).

Methods

Through a comprehensive literature search for genetic variants involved in the CHD association study, we harvested a total of 10 genes (12 variants) for the current meta-analyses. These genes consisted of GPX1 (rs1050450), PPARD (rs2016520), ALOX15 (rs34210653), SELPLG (rs2228315), FCGR2A (rs1801274), CCL5 (rs2107538), CYP1A1 (rs4646903), TP53 (rs1042522), CX37 (rs1764391), and PECAM1 (rs668, rs12953, and rs1131012).

Results

A total of 45 studies among 23,314 cases and 28,430 controls were retrieved for the meta-analyses of 12 genetic variants. The results showed a significant association between the GPX1 rs1050450 polymorphism and CHD (odd ratio (OR) = 1.61, 95% confidence interval (CI) = 1.25–2.07, P = 0.0002). Other meta-analyses of the rest 11 variants suggested a lack of association with the risk of CHD.

Conclusion

Our results confirmed that GPX1 rs1050450 was associated with susceptibility to CHD in Chinese and Indian populations.  相似文献   
8.
The aim of this study was to investigate the association between C-reactive protein (CRP) gene polymorphism and metabolic syndrome (MetS) with premature coronary artery disease (PCAD). 116 patients with PCAD (58 with MetS and 58 without MetS) and 119 controls were included in the study. CRP gene + 1059 G>C polymorphism was analyzed by polymerase chain reaction. Serum hs-CRP was measured using high-sensitivity enzyme-linked immunosorbent assay. Carriers of C allele of the CRP + 1059 G>C polymorphism had 3.37 fold increased risk to develop MetS in patients with PCAD. In addition CRP gene and hs-CRP levels were independent risk factors for PCAD and MetS. The present study provides new evidence that the presence of CRP + 1059 G>C polymorphism and hs-CRP levels are independent determinants of PCAD and MetS in Egyptians. The results of our study suggest a synergistic effect of CRP C allele with classical risk factors such as hypertension, obesity, dyslipidemia and MetS.  相似文献   
9.
Intentional cranial deformations (ICD) have been observed worldwide but are especially prevalent in preColombian cultures. The purpose of this study was to assess the consequences of ICD on three cranial cavities (intracranial cavity, orbits, and maxillary sinuses) and on cranial vault thickness, in order to screen for morphological changes due to the external constraints exerted by the deformation device. We acquired CT‐scans for 39 deformed and 19 control skulls. We studied the thickness of the skull vault using qualitative and quantitative methods. We computed the volumes of the orbits, of the maxillary sinuses, and of the intracranial cavity using haptic‐aided semi‐automatic segmentation. We finally defined 3D distances and angles within orbits and maxillary sinuses based on 27 anatomical landmarks and measured these features on the 58 skulls. Our results show specific bone thickness patterns in some types of ICD, with localized thinning in regions subjected to increased pressure and thickening in other regions. Our findings confirm that volumes of the cranial cavities are not affected by ICDs but that the shapes of the orbits and of the maxillary sinuses are modified in circumferential deformations. We conclude that ICDs can modify the shape of the cranial cavities and the thickness of their walls but conserve their volumes. These results provide new insights into the morphological effects associated with ICDs and call for similar investigations in subjects with deformational plagiocephalies and craniosynostoses. Am J Phys Anthropol 151:110–119, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
10.
The epicardium and coronary vessels originate from progenitor cells in the proepicardium. Here we show that Tbx18, a T-box family member highly expressed in the proepicardium, controls critical early steps in coronary development. In Tbx18−/− mouse embryos, both the epicardium and coronary vessels exhibit structural and functional defects. At E12.5, the Tbx18-deficient epicardium contains protrusions and cyst-like structures overlying a disorganized coronary vascular plexus that contains ectopic structures resembling blood islands. At E13.5, the left and right coronary stems form correctly in mutant hearts. However, analysis of PECAM-1 whole mount immunostaining, distribution of SM22αlacZ/+ activity, and analysis of coronary vascular casts suggest that defective vascular plexus remodeling produces a compromised arterial network at birth consisting of fewer distributing conduit arteries with smaller lumens and a reduced capacity to conduct blood flow. Gene expression profiles of Tbx18/ hearts at E12.5 reveal altered expression of 79 genes that are associated with development of the vascular system including sonic hedgehog signaling components patched and smoothened, VEGF-A, angiopoietin-1, endoglin, and Wnt factors compared to wild type hearts. Thus, formation of coronary vasculature is responsive to Tbx18-dependent gene targets in the epicardium, and a poorly structured network of coronary conduit vessels is formed in Tbx18 null hearts due to defects in epicardial cell signaling and fate during heart development. Lastly, we demonstrate that Tbx18 possesses a SRF/CArG box dependent repressor activity capable of inhibiting progenitor cell differentiation into smooth muscle cells, suggesting a potential function of Tbx18 in maintaining the progenitor status of epicardial-derived cells.  相似文献   
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