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The blood flow pattern investigations are of great importance in coronary blood flow destabilization pathogenesis understanding, and consequently in acute coronary event (ACE) risk stratification in patients with coronary heart disease. The aim of the study was to research the principal hormonal and metabolic blood flow regulative aspects and its structure in patients with ischemic heart disease and the contribution to cumulative ACE risk.A total of 182 patients with stable angina pectoris were included in the prospective study (2000–2006). Complex clinical examination, biochemical tests and blood tests were performed. Whole-blood (WB) viscosity, erythrocyte aggregation and deformation ability, WB suspension stability, and initial erythrocytes disaggregation parameter were studied. Dynamic characteristics of blood flow were obtained in the experiment.Received results allow marking the principle components of blood flow pattern with proven high prognostic value of ACE in patients with ischemic heart disease. ACE risk stratification program was developed.  相似文献   
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Host response plays a major role in the pathogenesis of Helicobacter pylori-induced gastroduodenal disease including adenocarcinoma of the distal stomach. Vascular endothelial growth factor (VEGF) is an important modulator of gastric mucosal repair and is overexpressed in gastric cancer. The present study sought to evaluate the expression of VEGF in the gastric mucosa of H. pylori-infected and H. pylori-non-infected dyspeptic patients. Fifteen H. pylori-infected and 15 H. pylori-non-infected dyspeptic patients were studied. Diagnosis of H. pylori infection was based on rapid urease test and histology. VEGF protein expression was assessed by western blotting. VEGF mRNA expression was assessed by RT-PCR. VEGF localization in the gastric mucosa and neo-angiogenesis were determined by immunohistochemistry. VEGF protein and mRNA expression was significantly greater in H. pylori-infected than in non-infected patients. Immunohistochemistry showed that VEGF expression was more intense in the gastric gland compartment of H. pylori-infected mucosa than in the non-infected mucosa. The increase in VEGF expression was associated with a significant increase in neo-angiogenesis as assessed by determination of CD34-positive micro-vessels. H. pylori gastritis is therefore associated with up-regulation of VEGF expression, which parallels the increased formation of blood vessels in the gastric mucosa. It is postulated that increased VEGF expression and neo-angiogenesis may contribute to H. pylori-related gastric carcinogenesis.  相似文献   
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小鼠肥大细胞瘤P815特异抗原P1A的克隆与表达   总被引:6,自引:1,他引:5  
目的 克隆小鼠肥大细胞瘤P815细胞株的PIA基因以制备肿瘤DNA疫苗,方法 用RT-PCR方法制备PIA基因,以哺乳细胞高效表达质粒pCI-neo为载体,构建重组DNA疫苗。重组体用克隆位点上游和下游的T7和T13启动了序列为测序引物,用自动测序仪测定鉴定克隆的正确性。再将鉴定过的重组质粒用磷酸钙法转化293细胞,用RT-PCR法鉴定转化细胞中PIA基因的表达。结果 正确构建了PIA/pCI-n  相似文献   
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Prognosis in prostate cancer is determined, in greater part, by the presence of metastases. Bone metastases can occur in any part of the skeleton even, for example, at the base of the skull. We present a case of a 78 year old male who, in December 2001, presented with paralysis of the third cranial nerve. The NMR and CAT scans were normal and circulating levels of PSA were elevated. He was referred to the Urology Service where the treatment guidelines included complete androgen block. Subsequently, he developed retro-orbital pain, divergent strabismus and palpebral ptosis. CAT and NMR indicated a soft tissue mass at the sphenoid level. Treatment was Gamma Knife Radio-surgery. Since August 2004, in conjunction with the latest rise in PSA, the patient's general status deteriorated considerably and he was referred to the Oncology Service. there was an increase in the paralysis of the third, fourth and sixth cranial nerve (complete left ophthalmoplegia) and left-central facial paralysis. Metastases from prostate cancer can be disseminated via the lymphatic or the blood system. Currently, there are more metastases from large-size tumours. Metastases are critical in prostate cancer because of their adverse effect on the patient's survival. Measurements of circulating levels of prostate specific antigen and prostate acid phosphatase are very useful in the clinical diagnosis of the primary tumour, or its metastases.  相似文献   
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Introduction and objectivesThis study aimed to determine the safety and efficacy of modifying the classic implantation technique for aortic transcatheter heart valve (THV) implantation to a cusp-overlap-projection (COP) technique to achieve a higher implantation depth and to reduce the burden of new permanent pacemaker implantation (PPMI) at 30 days. Aortic self-expanding THV carries an elevated risk for PPMI. A higher implantation depth minimizes the damage in the conduction system and may reduce PPMI rates.MethodsFrom March 2017, 226 patients were consecutively included: 113 patients were treated using the COP implantation technique compared with the previous 113 consecutive patients treated using the classic technique. In all patients, implantation depth was assessed by 3 methods (noncoronary cusp to the THV, mean of the noncoronary cusp and the left coronary cusp to the THV, and the deepest edge from the left coronary cusp and the noncoronary cusp to the THV).ResultsThe COP group had a lower implantation depth than the group treated with the classic technique (4.8 mm ± 2.2 vs 5.7 mm ± 3.1; P = .011; 5.8 mm ± 3.1 vs 6.5 mm ± 2.4; P = .095; 7.1 mm ± 2.8 vs 7.4 mm ± 3.2; P = .392). Forty patients (17.7%) required a new PPMI after the 30-day follow-up but this requirement was significantly lower in the COP group (12.4% vs 23%, P = .036). The COP implantation technique consistently protected against the main event (OR, 0.45; 95%CI, 0.21-0.97; P = .043), with similar procedural success rates and complications.ConclusionsThe COP implantation technique is a simple modification of the implantation protocol and provides a higher implantation depth of self-expanding-THV with lower conduction disturbances and PPMI rates.  相似文献   
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Recently, computer‐designed three‐dimensional (3D) printing techniques have emerged as an active research area with almost unlimited possibilities. In this study, we used a computer‐designed 3D scaffold to drive new bone formation in a bone defect. Poly‐L‐lactide (PLLA) and bioactive β‐tricalcium phosphate (TCP) were simply mixed to prepare ink. PLLA + TCP showed good printability from the micronozzle and solidification within few seconds, indicating that it was indeed printable ink for layer‐by‐layer printing. In the images, TCP on the surface of (and/or inside) PLLA in the printed PLLA + TCP scaffold looked dispersed. MG‐63 cells (human osteoblastoma) adhered to and proliferated well on the printed PLLA + TCP scaffold. To assess new bone formation in vivo, the printed PLLA + TCP scaffold was implanted into a full‐thickness cranial bone defect in rats. The new bone formation was monitored by microcomputed tomography and histological analysis of the in vivo PLLA + TCP scaffold with or without MG‐63 cells. The bone defect was gradually spontaneously replaced with new bone tissues when we used both bioactive TCP and MG‐63 cells in the PLLA scaffold. Bone formation driven by the PLLA + TCP30 scaffold with MG‐63 cells was significantly greater than that in other experimental groups. Furthermore, the PLLA + TCP scaffold gradually degraded and matched well the extent of the gradual new bone formation on microcomputed tomography. In conclusion, the printed PLLA + TCP scaffold effectively supports new bone formation in a cranial bone defect.  相似文献   
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BackgroundThe implications and potential challenges of coronary access after redo transcatheter aortic valve replacement (TAVR) are unknown.ObjectivesThe authors sought to evaluate the impact of different transcatheter heart valve (THV) designs, neoskirt height, implant technique, and cell misalignment on coronary access after redo TAVR.MethodsDifferent THV designs (Sapien 3 [Edwards Lifesciences LLC], Evolut Pro [Medtronic], ACURATE neo [Boston Scientific Corporation], and Portico [Abbott Structural Heart]) and sizes were implanted inside Sapien XT (Edwards Lifesciences LLC) and Evolut R (Medtronic) THVs, which were modeled as the “failed” THVs, at different implant depths. Valve combinations underwent micro–computed tomography to determine the neoskirt height and dimensions of the lowest accessible cell for potential coronary access. This was compared with dimensions of 6-F/7-F/8-F coronary guiding catheters.ResultsRedo TAVR combinations resulted in a wide range of neoskirt heights (15.4-31.6 mm) and a variable diameter of the lowest accessible cell (1.9-21.8 mm). An ACURATE neo implanted in a Sapien XT resulted in the largest accessible cells, whereas a Portico implanted in a Sapien XT resulted in the lowest neoskirt heights. The smallest accessible cell was observed in the Evolut Pro–in–Evolut R configuration with higher neoskirt heights. Redo TAVR in a tall frame valve with supra-annular leaflets caused a taller neoskirt height. In Evolut-in-Evolut combinations, misalignment of the cells of the 2 THVs reduced the cell area by 30% to 50% compared with an aligned configuration.ConclusionsThis study demonstrates that different redo TAVR combinations are not equivalent in terms of future coronary access. Redo TAVR using a tall frame valve in a failed tall frame valve and misaligned cells may lead to potentially challenging coronary access.  相似文献   
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