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Objective. To observe the regulating effects of vascular endothelial growth factor (VEGF) and angiotensinⅡ (ANG II) on the frog's pericardium, lymphatic stomata and angiogenesis so as to reveal their effects and mechanism on the mesothelial permeability, lymphatic stoma regulation and myocardial hypertrophy. Methods. VEGF and ANGⅡ were injected into the frog's peritoneal cavity so as to examine the changes of the pericardial stromata by using transmission electron microscopy, scanning electron microscopy and computerized imaging analysis. Results. Scattered distributed pericardial stomata were found on the parietal pericardium of the frog with a few sinusoid mesothelial cells, whose blood supply was directly from the cardiac chambers flowing into the trabecular spaces of the myocardium (because there are no blood vessels in the myocardium of the frog). The average diameters of the pericardial stomata in VEGF and ANGⅡ groups were 1.50 μ m and 1.79 μ m respectively, which were much larger than those in the control group (0.72 μ m, P< 0.01); the average distribution densities of the stomata were 8.25/0.1 mm2 and 12.80/0.1 mm2 in VEGF and ANGⅡ groups, which were also much higher than those in the control group (3.57/0.1 mm2, P< 0.01); the sinusoid areas in VEGF and ANGⅡ groups were 2442.95 μ m2/0.1 mm2 and 2121.79 μ m2/0.1 mm2, which were larger than that in the control group (995.08 μ m2 /0.1 mm2 , P< 0.01); no angiogenesis was found in the frogs of the experimental groups. Conclusions. VEGF and ANGⅡ could strongly regulate the pericardial stomata by increasing their numbers and openings with larger diameters and higher distribution density. They could also increase the sinusoid areas with the result of the higher permeability of the pericardium, which clearly indicated that VEGF and ANGⅡ could speed up the material transfer of the pericardial cavity and play an important role in preventing myocardial interstitial edema. Yet there was no strong evidence to show the angiogenesis in the myocardium.
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影像分析对肝肿瘤切除可行性及手术难点的评估与体会
现代影像技术的临床普及应用,大大提高了肝脏外科疾病的诊断准确率、手术切除率和术后疗效.术前对肝脏影像仔细地分析,结合临床资料和经验,可以帮助外科医生更准确、合理地选择佳治疗方案,更安全地进行手术治疗.
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缺血性卒中患者阿司匹林治疗后脑内微出血的MRI相位敏感图分析
抗血小板制剂--阿司匹林对预防脑卒中及心血管病复发有疗效.长期口服抗血小板药物可以降低卒中复发、心肌梗死的危险性,但口服阿司匹林可能增加脑内出血的危险性[1-4].