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51.
骨髓单个核细胞培养上清促进内皮细胞增殖作用   总被引:3,自引:0,他引:3  
目的:探讨体外培养骨髓细胞分泌促血管生长因子的能力及培养上清对内皮细胞增殖的影响。方法:采用密度梯度离心法分离出大鼠骨髓单个核细胞进行体外培养,并连续收集4周培养上清。酶联免疫吸附实验(ELISA)法测定上清中血管内皮细胞生长因子(VEGF);以含有不同浓度上清的培养液培养人脐静脉内皮细胞,分析单个核细胞培养上清对内皮细胞增殖的影响。结果:加入单个核细胞培养上清各组MTT比色光密度值较对照组明显增加(P<0.05)。第1,2,3,4周骨髓单个核细胞体外培养上清中VEGF分别为(24.40±7.99,89.28±5.13,115.24±10.08,157.00±15.64)pg/ml。结论: 骨髓单个核细胞培养上清可促进体外培养的人脐静脉内皮细胞增殖,体外培养的骨髓单个核细胞可持续分泌VEGF。  相似文献   
52.
Background and objective Atypical ‘cardiac‘ chest pain (ACCP) is not usually caused by myocardial ischaemia. Current noninvasive investigations for these symptoms are not yet as accurate as invasive coronary angiography. The latest 64-row multi-detector computed tomography (MDCT) technology is non-invasive, has high specificity and negative predictive values for the detection of significant coronary disease. Our aim was to investigate if this modality can provide more information in the assessment of outpatients with ACCP in addition to established cardiovascular risk scores. Methods Seventy consecutive patients presenting to the outpatient clinic with ACCP underwent 64-row MDCT scan of the coronary arteries. They were categorized into low, medium or high risk groups based upon the Framingham and PROCAM scores. We defined a clinically abnormal MDCT scan as coronary stenosis =50% or calcium score >400 Agatston. Results Fifty-three (75.7%) patients did not have clinically abnormal scans. Framingham score classified 43 patients as low-risk while PROCAM classified 59 patients as low-risk. MDCT scans were abnormal for 18.6% and 22.0% of the respective low-risk group of patients. For patients with medium-to-high risk, 33.3% and 36.4% of Framingham and PROCAM patient groups respectively had abnormal MDCT scans. Conclusion MDCT adds valuable information in the assessment of patients with ACCP by identifying a significant proportion of patients categorized as low-risk to have underlying significant coronary stenosis and coronary calcification by established cardiovascular risk scores.  相似文献   
53.
Background Elderly patients generally have higher occurrence of coronary calcification, increased heart rate and difficulty with prolonged breath-holding. The aim of our study was to investigate the feasibility and accuracy of using 64-row multi-detector computed tomography (MDCT) in the assessment of coronary artery stenoses in elderly patients. Methods One hundred and fifty two patients with suspected or known coronary artery disease were divided into 4 groups according to their age (Group A: 40-49 years, n=34; Group B: 50-59 years, n=57; Group C: 60-69 years, n=48; Group D: 70 years and above; n=13). Coronary CT angiography (CTA) using a 64-row MDCT was performed and the findings were compared with that of conventional coronary angiography (CCA). Using axial images, multi-planar reconstructions (MPR) and maximum intensity projections (MIP), coronary segments of lumen diameter = 1.5mm were analyzed for the presence of significant stenosis (= 50% ). Results Percentages of poor image quality from coronary CTA preventing reliable correlations with CCA were 21%, 14%, 19% and 62% in Groups A to D respectively. Patients in Group D had significantly higher calcium scores compared with the other groups (P<0.001). In patients where CTA images were of acceptable quality, percentages of accurate correlations with CCA were 89.8%, 93.4%, 86.6% and 78.0% for Groups A to D respectively. There were no significant difference in serum creatinine, heart rate and contrast volume between the 4 groups. Conclusions The 64-row MDCT coronary angiography was less accurate and feasible for patients aged 70 years or above due to heavy coronary calcification and inability to perform a satisfactory breath-hold. However, a high diagnostic accuracy with the MDCT is possible in patients aged less than 70 years.(J Geriatric Cardiol 2006;3(1):9-14)  相似文献   
54.
目的 比较裸鼹鼠与C57BL/6J小鼠组织中抑癌基因p53表达的差异,并分析p53基因在不同年龄裸鼹鼠不同组织中表达水平的差异.方法 采用Western blotting检测新生裸鼹鼠与C57BL/6J小鼠肝脏、肺脏、脑、肾脏中p53蛋白的表达,进一步比较了不同年龄裸鼹鼠肝脏、肺脏、脑、肠道中p53蛋白的表达,同时采用RT-PCR检测了裸鼹鼠肝脏、肺脏中p53基因的转录水平.以及低氧处理裸鼹鼠皮肤成纤维细胞中p53基因的表达水平.结果 新生裸鼹鼠肝脏、肺脏、脑、肾脏组织中p53蛋白的表达低于新生C57BL/6J小鼠组织,成年裸鼹鼠肝脏、肺脏组织中p53蛋白表达量亦显著高于幼年裸鼹鼠.裸鼹鼠成纤维细胞在低氧条件下p53蛋白的表达量较高,并且随着低氧处理时间的延长,表达量进一步升高.结论 新生裸鼹鼠组织中抑癌基因p53表达水平显著低于C57BL/6J小鼠,并且p53基因随着年龄增长而发生变化.  相似文献   
55.
目的探讨康复新液联合米诺环素软膏治疗慢性牙周炎的临床疗效。方法选取2013年8月—2015年8月三亚市人民医院收治的慢性牙周炎患者90例,患牙共计106颗,采用随机数字表法分为对照组和治疗组,每组各45例、患牙53颗。对照组给予盐酸米诺软膏,将其注入牙周袋中直至充满,1次/周;治疗组在对照组基础上给予康复新液,约10 m L含漱5 min左右,4次/d。两组患者均治疗4周。观察两组的临床疗效,比较两组C反应蛋白(CRP)、白细胞介素-6(IL-6)、龈沟出血指数(SBI)、牙周附着水平(AL)、菌斑指数(PLI)和牙周袋深度(PD)变化情况。结果治疗后,对照组和治疗组的总有效率分别为79.25%、96.23%,两组比较差异有统计学意义(P0.05)。治疗后,对照组SBI、AL、PLI和PD显著降低,治疗组CRP、SBI、AL、PLI和PD显著降低,同组治疗前后比较差异有统计学意义(P0.05);且治疗组这些观察指标的降低程度明显优于对照组,两组比较差异具有统计学意义(P0.05)。结论康复新液联合米诺环素软膏治疗慢性牙周炎具有较好的临床疗效,能改善临床症状,缓解炎症反应,具有一定的临床推广应用。  相似文献   
56.
Koskinen P, Viikari J, Irjala K, Kaihola H-L, Seppälä P. C-peptide determination in the choice of treatment in diabetes mellitus. Scand J Clin Lab Invest 1985; 45: 589-597.

The predictive value of the intravenous glucagon test in assessing the requirement of insulin therapy in diabetes mellitus was evaluated in 105 adult diabetics. Basal and stimulated C-peptide concentrations and increments of C-peptide concentration were examined separately among newly and previously diagnosed diabetics. The poststimulatory C-peptide concentration of 0.6 nmol/1 (Novo, antibody M 1230) proved to be the most reliable basis for the choice of therapy. Adequate therapy could have been assessed in 70 cases (67%) without glucagon stimulation. To derive maximal information of plasma C-peptide concentrations, a biphasic scheme of the use for C-peptide determinations and glucagon stimulation is presented. Basal and stimulated C-peptide levels of insulin-requiring diabetics correlated negatively with the duration of diabetes but they did not correlate with the relative body weights. Basal and stimulated C-peptide levels of non-insulin-requiring diabetics did not correlate with the duration of diabetes, but they correlated positively with the relative body weights.  相似文献   
57.
目的 运用网络药理学方法探讨祛痹痛风饮治疗痛风的活性成分、作用靶点及其潜在的治疗作用机制.方法 基于中药系统药理学数据库与分析平台(TCMSP)获取祛痹痛风饮的活性成分和作用靶点,结合Uniprot数据库对靶点进行标准化处理.采用Cytoscape 3.7.2软件绘制出祛痹痛风饮的活性成分–痛风靶点网络.通过GeneC...  相似文献   
58.
The efficacy of lamivudine re-treatment in chronic hepatitis B (CHB) patients who relapse after HBeAg seroconversion with lamivudine has not been investigated. The aim of this study was to evaluate the efficacy of lamivudine re-treatment in relapsed patients. Among 192 patients who had achieved HBeAg seroconversion with lamivudine at a dose of 100 mg/day, 121 patients discontinued lamivudine. Relapse occurred in 49 patients (40.5%). Thirty-three relapsed patients received lamivudine re-treatment for at least 6 months. The mean duration of lamivudine re-treatment was 16 months and the follow-up period was 8.9 months. HBeAg seroconversion was achieved in 23 patients (69.7%). The cumulative HBeAg seroconversion rates at 5, 9, and 12 months were 60, 64, and 67%, respectively. The mean time to HBeAg seroconversion in lamivudine re-treatment was shorter than that in the initial therapy (4.7 months vs. 9.7 months). Viral breakthrough occurred in six (18.2%) patients. All patients with viral breakthrough were accompanied by elevation of serum alanine aminotransferase (ALT) levels. Among 15 patients who discontinued lamivudine re-treatment after HBeAg seroconversion, relapse occurred in six patients (40%). All relapses occurred within 9 months after the discontinuation of lamivudine re-treatment. In conclusion, lamivudine re-treatment in relapsed patients after initial lamivudine therapy had a higher response rate and shorter duration to HBeAg seroconversion than during the initial therapy. However, HBeAg seroconversion induced by lamivudine re-treatment was not durable.  相似文献   
59.
The aim of the present review is to summarize the current knowledge regarding pharmacological prevention and treatment of acute pancreatitis (AP) based on experimental animal models and clinical trials. Somatostatin (SS) and octreotide inhibit the exocrine production of pancreatic enzymes and may be useful as prophylaxis against Post Endoscopic retrograde cholangiopancreatography Pancreatitis (PEP). The protease inhibitor Gabexate mesilate (GM) is used routinely as treatment to AP in some countries, but randomized clinical trials and a meta-analysis do not support this practice. Nitroglycerin (NGL) is a nitrogen oxide (NO) donor, which relaxes the sphincter of Oddi. Studies show conflicting results when applied prior to ERCP and a large multicenter randomized study is warranted. Steroids administered as prophylaxis against PEP has been validated without effect in several randomized trials. The non-steroidal anti-inflammatory drugs (NSAID) indomethacin and diclofenac have in randomized studies showed potential as prophylaxis against PEP. Interleukin 10 (IL-10) is a cytokine with anti-inflammatory properties but two trials testing IL-10 as prophylaxis to PEP have returned conflicting results. Antibodies against tumor necrosis factor-alpha (TNF-α) have a potential as rescue therapy but no clinical trials are currently being conducted. The antibiotics beta- lactams and quinolones reduce mortality when necrosis is present in pancreas and may also reduce incidence of infected necrosis. Evidence based pharmacological treatment of AP is limited and studies on the effect of potent anti-inflammatory drugs are warranted.  相似文献   
60.

Introduction

Magnetic resonance imaging using the delayed contrast-enhanced (DE-MRI) method can be used for characterizing and quantifying myocardial infarction (MI). Electrocardiogram (ECG) score after the acute phase of MI can be used to estimate the portion of left ventricular myocardium that has infracted. There are no comparison of serial changes on ECG and DE-MRI measuring infarct size.

Aim

The general aim of this study was to describe the acute, healing, and chronic phases of the changes in infarct size estimated by the ECG and DE-MRI. The specific aim was to compare estimates of the Selvester QRS scoring system and DE-MRI to identify the difference between the extent of left ventricle occupied by infarction in the acute and chronic phases.

Methods

In 31 patients (26 men, age 56 ± 9) with reperfused ST-elevation MI (11 anterior, 20 inferior), standard 12-lead ECG and DE-MRI were taken from 1 to 2 days (acute), 1 month (healing), and 6 months (chronic) after the MI. Selvester QRS scoring was used to estimate the infarct size from the ECG.

Results

The correlation values between infarct size measured by DE-MRI and QRS scoring range from 0.33 to 0.43 higher for anterior than inferior infarcts. The infarct size estimated by QRS scoring was larger (about 5% of the left ventricle) than infarct size by DE-MRI acute and 1 month, but at 6 months, there was no difference. In about half of the patients, the QRS score agreed with DE-MRI in change of infarct size from acute to 6 months.

Conclusion

In conclusion, the Selvester QRS scoring system is in half of the patients with reperfused first time MI in good accordance with DE-MRI in identifying a decrease or no change in the extent of left ventricle occupied by infarction in the acute and chronic phases.  相似文献   
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