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941.
经冠状动脉注射骨髓单个核细胞影响心肌细胞凋亡的实验研究 总被引:1,自引:0,他引:1
目的观察经冠状动脉注射方式移植骨髓单个核细胞对心脏功能的改善和心肌细胞凋亡的影响。方法结扎小型猪冠状动脉制备心肌梗死模型,然后经冠状动脉注射骨髓单个核细胞,术后3周用超声心动图以及左心室造影检测心功能.核素心肌显像观察心肌灌注,冠状动脉造影观察侧支循环形成.用TUNEL检测心肌细胞凋亡。结果把骨髓单个核细胞通过冠状动脉注射到猪心肌梗死模型,显示左心室dp/dtmax较对照组增高,心肌灌注显著改善。冠状动脉有侧支循环形成,缺血心肌细胞;较对照组减少了53.6%结论骨髓单个核细胞心肌内移植可改善心脏收缩功能,可能与移植细胞抑制心肌细胞凋亡有关。 相似文献
942.
SCHAFER R. O.; HEINE H.; BOHM J.; SCHILDHAUS I.; WALLRABE D.; COBET H.; RUSER H. 《European heart journal》1987,8(9):1032-1038
A case is reported of bilateral atrial myxomas diagnosed noninvasivelyby echocardiography and successfully removed. The excised tumormass consisted of a mobile right atrial myxoma prolapsing intothe right ventricle and a less mobile, not prolapsing myxomain the left atrium. The operation was performed entirely onthe basis of echocardiographic findings, which correlated wellwith the operative results. Further investigation by computertomography verified the diagnosis, but added no extra informationof importance for therapy. Diagnostic aspects of the combinedapplication of M-mode and cross-sectional echocardiography withDoppler echocardiography are emphasized. Postoperative follow-upechocardiography showed the complete removal of the myxomasand improvement of cardiac function. 相似文献
943.
《Revista espa?ola de cardiología》2020,73(8):623-631
Introduction and objectivesTo evaluate whether a genetic risk score (GRS) improves prediction of recurrent events in young nondiabetic patients presenting with an acute myocardial infarction (AMI) and identifies a more aggressive form of atherosclerosis.MethodsWe conducted a prospective study with consecutive nondiabetic patients aged < 55 years presenting with AMI. We performed a genetic test, cardiac computed tomography, and analyzed several biomarkers. We studied the association of a GRS composed of 11 genetic variants and a primary composite endpoint (cardiovascular mortality, a recurrent event, and cardiac hospitalization).ResultsA total of 81 patients were studied and followed up for a median of 4.1 years. There were 24 recurrent cardiovascular events. Compared with the general population, study participants had a higher prevalence of 9 out of 11 risk alleles. The GRS was significantly associated with recurrent cardiovascular events, especially when baseline low-density lipoprotein cholesterol (LDL-C) levels were elevated. Compared with the low-risk GRS tertile, the multivariate-adjusted HR for recurrences was 10.2 (95%CI, 1.1-100.3; P = .04) for the intermediate-risk group and was 20.7 (2.4-181.0; P = .006) for the high-risk group when LDL-C was ≥ 2.8 mmol/L (≥ 110 mg/dL). Inclusion of the GRS improved the C-statistic (ΔC-statistic = 0.086), cNRI (continuous net reclassification improvement) (30%), and the IDI (integrated discrimination improvement) index (0.05). Cardiac computed tomography frequently detected coronary calcified atherosclerosis but had limited value for prediction of recurrences. No association was observed between metalloproteinases, GRS and recurrences.ConclusionsA multilocus GRS may identify individuals at increased risk of long-term recurrences among young nondiabetic patients with AMI and improve clinical risk stratification models, particularly among patients with high baseline LDL-C levels. 相似文献
944.
Amir Kurtaran Alexander Becherer Franz Pfeffel Christian Müller Tatjana Traub Jrn Schmaljohann Klaus Kaserer Markus Raderer Wolfgang Schima Robert Dudczak Kurt Kletter Irene Virgolini 《Liver international》2000,20(6):487-490
Abstract: Aim: The aim of this paper is to describe the imaging pattern of focal nodular hyperplasia (FNH) by 18F‐fluorodeoxyglucose (18F‐FDG) positron emission tomography (PET). Methods: Eight consecutive asymptomatic patients with histologic proof of FNH underwent 18F‐FDG PET imaging. The lesions were found incidentally. The 18F‐FDG PET imaging was performed with a dedicated PET tomograph after intravenous injection of 300–370 MBq 18F‐FDG. The 18F‐FDG accumulation in the lesions was (semi)quantified by calculating the standardized uptake value (SUV) and SUV has been corrected for the lean body mass (LBM). Eight patients with liver metastases spread from melanoma (n=2) and colorectal carcinoma (n=6) served as controls. The size of the FNH lesions and of the control group ranged from 2.0 to 8.5 cm (mean 4.83 cm±2.37) and from 1.5 to 6 cm (mean 3.28±1.52), respectively. Results: While in malignant liver lesions the accumulation of 18F‐FDG was significantly increased, all FNH lesions showed normal or even decreased accumulation of 18F‐FDG. In FNH lesions, SUV ranged between 1.5 and 2.6 (mean 2.12±0.38), whereas all liver metastases showed an increased SUV ranging between 6.20 and 16.00 (mean 10.07±3.79). The SUV corrected for LMB (SUVLBM) was similar to the SUV and ranged between 0.9 and 2.2 (mean 1.81±0.41) for FNH and between 5.9 and 16.3 (mean 9.15±4.03), respectively. Conclusion: In contrast to liver metastases, there is no increased glucose metabolism in FNH in vivo. The imaging feature of FNH by 18F‐FDG‐PET imaging is not specific for FNH; however, it may be helpful to differentiate FNH from liver metastases in cancer patients if radiological methods are not diagnostic. 相似文献
945.
Enhancement of insulin-stimulated myocardial glucose uptake in patients with Type 2 diabetes treated with rosiglitazone. 总被引:3,自引:0,他引:3
K. Hllsten K. A. Virtanen F. Lnnqvist T. Janatuinen M. Turiceanu T. Rnnemaa J. Viikari T. Lehtimki J. Knuuti P. Nuutila 《Diabetic medicine》2004,21(12):1280-1287
AIMS: Peroxisome proliferator-activated receptor gamma (PPARgamma) activators have recently been identified as regulators of cellular proliferation, inflammatory responses and lipid and glucose metabolism. These agents prevent coronary arteriosclerosis and improve left ventricular remodelling and function in heart failure after myocardial infarction. Improvement in myocardial metabolic state may be one of the mechanisms behind these findings. The aim of this study was to investigate the effects of rosiglitazone on myocardial glucose uptake in patients with Type 2 diabetes. Placebo and metformin were used as control treatments. METHODS: Forty-four patients were randomized to treatment with rosiglitazone (4 mg b.i.d.), metformin (1 g b.i.d.) or placebo in a 26-week double-blinded trial. Myocardial glucose uptake was measured using [(18)F]-2-fluoro-2-deoxy-D-glucose ([(18)F]FDG) and positron emission tomography (PET) during euglycaemic hyperinsulinaemia before and after the treatment. RESULTS: Rosiglitazone increased insulin-stimulated myocardial glucose uptake by 38% (from 38.7 +/- 3.4 to 53.3 +/- 3.6 micromol 100 g(-1) min(-1), P = 0.004) and whole body glucose uptake by 36% (P = 0.01), while metformin treatment had no significant effect on myocardial (40.5 +/- 3.5 vs. 36.6 +/- 5.2, NS) or whole body glucose uptake. Myocardial work as determined by the rate-pressure-product was similar between the groups. Neither treatment had any significant effect on fasting serum free fatty acids (FFA) but the FFA levels during hyperinsulinaemia were more suppressed in the rosiglitazone group (-47%, P = 0.02). Myocardial glucose uptake correlated inversely to FFA concentrations both before (r =-0.54, P = 0.002) and after (r = -0.43, P = 0.01) the treatment period in the pooled data. Furthermore, the increase in myocardial glucose uptake correlated inversely with interleukin-6 (IL-6) concentrations (r = -0.58, P = 0.03). CONCLUSIONS: In addition to the improvement in whole body insulin sensitivity, rosiglitazone treatment enhances insulin stimulated myocardial glucose uptake in patients with Type 2 diabetes, most probably due to its suppression of the serum FFAs. 相似文献
946.
目的 观察实性孤立性肺结节(SPN)高分辨率CT(HRCT)表现。方法 回顾性分析235例HRCT检出的实性SPN患者,其中54例良性(良性组),181例恶性(恶性组)。比较组间HRCT表现差异,包括分叶征、毛刺征、空洞征、空泡征、钙化、远端穿行血管、胸膜牵拉征、贴近胸膜及牵拉性肺气肿;评估差异有统计学意义的征象鉴别良、恶性SPN的效能,分析良、恶性SPN的影响因素。结果 组间毛刺征、胸膜牵拉征、钙化征象差异均无统计学意义(P均>0.05),其余征象差异均有统计学意义(P均<0.05)。血管集束征鉴别良、恶性SPN的效能最高,敏感度达92.30%。回归分析显示血管集束征是恶性SPN的危险征象,牵拉性肺气肿为其保护因素(P均<0.05)。结论 良、恶性SPN的HRCT表现存在差异,对鉴别诊断具有一定价值。 相似文献
947.
前体淋巴细胞恶性肿瘤以T细胞来源为主,而B淋巴母细胞性淋巴瘤(B-lymphoblastic lymphoma,B-LBL)仅占约10%,常累及皮肤或骨骼,纵隔受累少见。B-LBL与B淋巴母细胞白血病(B-acute lymphoblastic leukemia,B-ALL)可归为一类,骨髓中淋巴母细胞比例≥25%时为B-ALL,比例在5%~25%时应诊断为B-LBL骨髓浸润[1]。肾脏淋巴瘤少见,且多为继发性。本研究观察B-LBL/ALL肾脏浸润的18 F-FDG PET/CT表现。 相似文献
948.
目的 观察不同MYCN基因扩增状态的腹部神经母细胞瘤(NB)CT表现。方法 纳入172例腹部NB患儿,根据MYCN基因拷贝数分为MYCN组(n=47)及未扩增组(n=125)。比较组间肿瘤分布部位、大小、形态、密度、边界、钙化、囊变及坏死等CT征象差异;比较组间肿瘤实质的平均CT值及其与同一层面背部肌肉平均CT值差值的差异。结果 组间肿瘤大小、分布部位、形态、钙化、囊变及坏死、跨越中线生长情况差异均有统计学意义(P均<0.05),而静脉期强化方式差异无统计学意义(P>0.05);组间肿瘤与血管关系及邻近脏器侵犯情况差异均有统计学意义(P均<0.05);未扩增组静脉期肿瘤实质平均CT值及与同一层面背部肌肉平均CT值差值均显著高于MYCN组(P均<0.05)。结论 MYCN基因不同扩增状态的腹部NB肿瘤CT表现存在一定差异。 相似文献
949.
950.
目的 评估术前基于胸部CT平扫影像组学模型预测食管癌患者淋巴结转移的价值。方法 回顾性分析368例经术前内镜活检及术后病理确诊的食管癌患者,其中100例淋巴结转移、268例无淋巴结转移,按比例3 ∶ 1将其分为训练组(包括201例无淋巴结转移和75例淋巴结转移)和验证组(67例无淋巴结转移和25例淋巴结转移)。自胸部CT中提取食管癌病灶的影像组学特征,并以最小绝对收缩和选择算子(LASSO)回归进行降维,筛选与食管癌淋巴结转移关联度高的特征;采用支持向量机构建预测淋巴结转移的影像组学模型,并以受试者工作特征(ROC)曲线分析模型的诊断效能。结果 共提取1 046个组学特征参数,经LASSO降维筛选出11个特征参数用于建立预测淋巴结转移模型。影像组学模型预测训练组淋巴结转移的曲线下面积(AUC)为0.84,敏感度为84.00%,特异度为75.12%,准确率为77.54%;于验证组的AUC为0.82,敏感度为80.00%,特异度为77.61%,准确率为78.26%。结论 术前基于胸部CT平扫影像组学模型预测食管癌患者淋巴结转移具有较高价值。 相似文献