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61.
Cell interactions with nanostructures are of broad interest because of applications in controlling tissue response to biomedical implants. Here we show that dense and upright SiO2 coated nanorods nearly eliminate cell adhesion in fibroblasts and endothelial cells. The lack of adhesion is not due to a decrease in matrix protein adsorption on the nanostructures, but rather an inability of cells to assemble focal adhesions. Using spatially patterned nanorods, we show that cells display a preference for flat regions of the surface. Our results support a model in which interfering with nanoscale spacing of ligated integrins results in reduced cell adhesion and subsequent cell death. We propose that dense monolayers of nanorods are a promising nanotechnology for preventing mammalian cell fouling of biomaterials.  相似文献   
62.
有效提取心音包络对于检测S1、S2,分离杂音进而判断心脏病类型和严重程度具有重要意义.我们应用动力学复杂性,给出一种有效的心音包络提取方法及仿真结果.该方法能够有效分离二尖瓣关闭不全信号的S1、S2和杂音,明显突出肺动脉瓣关闭不全信号中幅度较低的S2,准确判断二尖瓣狭窄杂音持续时间.经验证,该方法具有对幅度变化的鲁棒性,在信号不同成分交界处,包络边沿变化陡峭,降低了后期心音成分提取和辨识工作的难度.  相似文献   
63.
Surgical treatment of patients with congestive heart failure (CHF) has steadily advanced from rescue procedures such as aneurysmectomy, rupture repair, ventricular assist devices (VADs), and transplantation to procedures that can prevent or delay the progression of cardiac dysfunction and failure. The latter include operations such as coronary artery bypass grafting (CABG) and mitral valve repair for patients with ischemic cardiomyopathy (ICMP) and mitral annular dilatation, ventricular restoration and remodeling, and cardiac resynchronization therapy. As the number of heart transplants reported worldwide continues to decline over the past decade (by over 30%), newer surgical therapies have emerged. A need arises for clinical registries such as the NIH-sponsored LVAD registry and registries for biventricular pacing and AICD implantation, for total artificial heart implants, and for mitral valve repair in patients with ICMP. Prospective trials comparing sole ventricular restoration therapy (SVR) to SVR with concomitant CABG/MVR, coronary sinus versus epicardial LV pacing for ventricular resynchronization therapy, trials comparing LVAD as destination therapy to AICD implants, mitral valve repair versus chordal-sparing valve replacement for ischemic and valvular cardiomyopathy, and off-pump versus on-pump CABG for patients with ICMP are urgently needed. Future research should also be directed toward drugs targeting “B-cell mediated” humeral vascular rejection—the Achilles heel of cardiac transplantation, xenotransplantation, permanently implantable VADs, gene therapy, and myocardial cell regeneration therapy.  相似文献   
64.
Cancer resistance in transgenic mice expressing the SAC module of Par-4   总被引:1,自引:0,他引:1  
Prostate apoptosis response-4 (Par-4) is a tumor-suppressor protein that induces apoptosis in cancer cells, but not in normal/immortalized cells. The cancer-specific proapoptotic action of Par-4 is encoded in its centrally located SAC domain. We report here the characterization of a novel mouse model with ubiquitous expression of the SAC domain. Although SAC transgenic mice displayed normal development and life span, they were resistant to the growth of spontaneous, as well as oncogene-induced, autochthonous tumors. Resistance to tumorigenesis was linked to inhibition of nuclear factor-kappaB activity and induction of apoptosis by the SAC domain. Collectively, our findings provide genetic evidence that the SAC domain of Par-4 confers cancer resistance in transgenic mice without compromising normal viability or aging, and may have therapeutic significance.  相似文献   
65.
A 91-year-old man presented with a 9.0 × 7.0 cm exophytic mass on the dorsum of the right foot, surrounded by a scaling hyperkeratotic plaque-like lesion that had been present for many years. He had similar long-standing hyperkeratotic plaque-like lesions on both legs. Histopathologic examination of the exophytic mass revealed a well-differentiated squamous cell carcinoma surrounded by an eccrine syringofibroadenoma (ESFA). Histochemistry, immunohistochemistry and electron microscopy support this diagnosis. To our knowledge, this is the only reported case of ESFA being intimately associated with a malignant neoplasm.  相似文献   
66.
Interleukin-10 (IL10), a pleiotropic cytokine secreted by type-2 helper (Th2) T cells, contributes to the oncogenic activation or inactivation of tumor-suppressor genes. The present study investigated whether hypomethylation of IL10 CpG island (CGI) was associated with the risk of developing gastric cancer (GC) and the prognosis of patients with GC. A fragment (hg18, chr1: 206945638-206945774) at the CGI of IL10 was selected for the present methylation assay. Quantitative methylation-specific PCR was used to evaluate the methylation of IL10 CGI in 117 tumor samples from patients with GC. The results demonstrated that IL10 CGI methylation was significantly lower in the tumor tissues compared with that in the paired adjacent non-tumor tissues (median percentage of methylated reference, 29.16 vs. 42.82%, respectively; P=4×10−8). Furthermore, results from receiver operating characteristic curve analysis identified a significant area under the curve of 0.706, with a sensitivity and a specificity of 77.8 and 58.1%, respectively, between cancer tissues and paired adjacent non-tumor tissues. Furthermore, the methylation of IL10 CGI was significantly associated with patients'' age at diagnosis (r=−0.201; P=0.03). Subgroup analyses demonstrated that the association between IL10 CGI hypomethylation and the risk of GC was specific for patients with low differentiation (P=1×10−7) and Borrmann types III+IV (P=1×10−7). In addition, IL10 CGI hypomethylation was significantly associated with the risk of GC for patients without smoking history (P=3×10−7) or a family history of cancer (P=2×10−7). The results from Kaplan-Meier survival analysis demonstrated that IL10 CGI hypomethylation was associated with a significantly shorter overall survival of patients with GC (P=0.041). Similar results were identified for patients with GC who did not have smoking history (P=0.037) or a family history of cancer (P=0.049). The results from this study demonstrated that IL10 CGI hypomethylation may be considered as a potential biomarker for the diagnosis and prognosis of patients with GC in the Chinese population.  相似文献   
67.
68.
大肠癌是中国发病率排名第三的癌症。虽然近年来手术技术和术后化疗效果已经取得不小的进展,但大肠癌的预后仍不令人满意,主要原因是肿瘤的复发和转移。大肠癌干细胞Wnt信号通路在肿瘤复发和转移中起重要作用,并已成为抗癌药物研发的新靶点。大肠癌干细胞Wnt信号通路的失调导致细胞内β-catenin水平升高,继而激活一系列致癌相关基因。因此,如果针对Wnt信号通路的小分子靶向药物可阻止或逆转这些异常变化,将有助于治疗大肠癌。本文对以Wnt通路为靶标的小分子药物的研究现状进行了回顾,并展望其未来可能的发展方向。  相似文献   
69.
ObjectiveThe purpose of this study is to analyze uterine electromyography burst patterns in patients with spontaneous labor and patients with uterine inertia.Materials and methodsUterine electromyography was recorded using 4 silver/silver chloride electrodes placed periumbilical. Thirty women in the spontaneous labor were enrolled. Uterine electromyography was also recorded from patients with uterine inertia before and after oxytocin treatment. EMG bursts were characterized by analysis of multiple variables including burst frequency, duration, root mean squared, amplitude, and total power.ResultsThere were significant reductions (P < .01) in all EMG burst characteristics. In addition, uterine electromyography parameters were all increased after oxytocin treatment and were comparable (P > .05) to patients in spontaneous labor.ConclusionsUterine electromyography can be used effectively to distinguish patients progressing with spontaneous labor from patients that develop uterine inertia. Uterine inertia is characterized by reduced EMG activity and failure of cervical dilation. Uterine electromyography is a quantitative, non-invasive assessment tool that contributes to the diagnosis, evaluation and management of patients with spontaneous labor and uterine inertia.  相似文献   
70.
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