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21.
目的:探讨鼻内翻性乳头状瘤及其癌变与p53基因的关系。方法:采用免疫组化方法(ABC法)对36例鼻内翻性乳头状瘤(IP)组织和16例鼻内翻性乳头状瘤癌变(IP+SCC)组织进行了p53蛋白检测。结果:36例IP均为p53蛋白阴性,而在16例IP+SCC组织中有5例为p53蛋白阳性,阳性率为31.3%(5/16),经统计学处理,二者差异显著(P〈0.001)。结论:p53蛋白异常表达可能与IP的发生  相似文献   
22.
慢性结肠炎在一定情况下可发生癌转化。慢性结肠炎“炎癌转化”是在线粒体能量代谢损伤、有氧糖酵解代谢上调的机制下,肠道上皮细胞代谢失衡,促使炎症微环境向肿瘤微环境转化的过程。认为由正气虚损而致太阴经、阳明经的寒热分离是结肠炎癌转化的触发机制,由邪毒鸱张诱发的气机升降失调是打破促瘤抑瘤平衡,进而邪聚成瘤的关键。临床治疗上应在中医恒动观理论指导下分清慢性结肠炎炎癌转化的不同阶段,灵活把握扶正与解毒的主次,改善肠道炎性环境,调节异常能量代谢,以延缓恶化时间,截断炎癌转化的进程。  相似文献   
23.
Nitinol (NiTi) alloys are gaining extensive attention due to their excellent mechanical, superelasticity, and biocompatibility properties. It is difficult to model the complex mechanical behavior of NiTi alloys due to the solid-state diffusionless phase transformations, and the differing elasticity and plasticity presenting from these two phases. In this work, an Auricchio finite element (FE) model was used to model the mechanical behavior of superelastic NiTi and was validated with experimental data from literature. A Representative Volume Element (RVE) was used to simulate the NiTi microstructure, and a microscale study was performed to understand how the evolution of martensite phase from austenite affects the response of the material upon loading. Laser Powder Bed Fusion (L-PBF) is an effective way to build complex NiTi components. Porosity being one of the major defects in Laser Powder Bed Fusion (L-PBF) processes, the model was used to correlate the macroscale effect of porosity (1.4–83.4%) with structural stiffness, dissipated energy during phase transformations, and damping properties. The results collectively summarize the effectiveness of the Auricchio model and show that this model can aid engineers to plan NiTi processing and operational parameters, for example for heat pump, medical implant, actuator, and shock absorption applications.  相似文献   
24.
中药是中华民族的瑰宝,经历了数千年的传承与发展,对人民的防病治病做出了不可磨灭的贡献,近年来各种疑难杂症频繁出现,中药的发展潜力更是受到了世界人民的关注和重视。伴随着中药现代化战略的实施,中药的发展也迎来了新的机遇与挑战。微生物转化是当前中药现代化研究的热点之一,就微生物转化的概念、特点以及微生物转化技术在中药中的应用现状进行概述,并对中药微生物转化的发展前景做展望。  相似文献   
25.
The malignant transformation of mature cystic teratoma is rare, thus occurring in only 1-2% of all cases. The most common malignancy arising in mature cystic teratoma is squamous cell carcinoma. Adenocarcinoma occurs with less frequency. We herein present a patient with an ovarian mature cystic teratoma who demonstrated a malignant transformation to well-differentiated adenocarcinoma. Malignant transformation was diagnosed preoperatively by contrast enhanced computed tomography (CT) and magnetic resonance imaging (MRI). Microscopically and immunohistochemically, the adenocarcinoma was considered to have arisen from the ciliated respiratory epithelium. After a 28-month of follow-up period, she remains free of the disease. This is the third reported case of adenocarcinoma arising in the respiratory epithelium of an ovarian mature cystic teratoma. Contrast enhanced CT and MRI are useful for making a preoperative diagnosis and an immunohistochemical study is helpful for defining its origin.  相似文献   
26.
The incidence of malignant transformation in mature cystic teratoma (MCT) of the ovary is less than 2% as reported in gynaecological and pathological literature. Here we present a series of five patients, who developed malignant transformation in MCT of the ovary, over a 6-year period (1999–2004). The morphological and clinico-pathological features of malignant transformation in MCT of the ovary are discussed.  相似文献   
27.
社会转型是医患信任嬗变的历史背景,医患信任嬗变是反映社会转型的基本侧面,单位制度变迁是透视二者关系的良好视角。新时期我国社会转型的重要表现是从“熟人社会”转向“生人社会”,直接引发了医患关系从互信到互不信的明显转变。“熟人社会”中医患信任主要是基于熟悉的人际信任,“生人社会”则呼唤基于规范的制度信任。人际信任加速失效、制度信任尚未完全建立造成信任结构断裂是医患信任危机发生的根源。“人际信任”与“制度信任”各有优势和不足,重建医患信任必须努力实现二者的有机结合。  相似文献   
28.
In the numerical analysis of manufacturing processes of metal parts, many material properties depending on, for example, the temperature or stress state, must be taken into account. Often these data are dependent on the temperature changes over time. Strongly non-linear material property relationships are usually represented using diagrams. In numerical calculations, these diagrams are analyzed in order to take into account the coupling between the properties. An example of these types of material properties is the dependence of the kinetics of phase transformations in the solid state on the rate and history of temperature change. In literature, these data are visualized Continuous Heating Transformation (CHT) and Continuous Cooling Transformation (CCT) diagrams. Therefore, it can be concluded that time series analysis is important in numerical modeling. This analysis can also be performed using neural networks. This work presents a new approach to storing and analyzing the data contained in the discussed CCT diagrams. The application of Long-Short-Term Memory (LSTM) neural networks and their architecture to determine the correct values of phase fractions depending on the history of temperature change was analyzed. Moreover, an area of research was elements that determine what type of information should be stored by LSTM network coefficients, e.g., whether the network should store information about changes of single phase transformations, or whether it would be better to extract data from differences between several networks with similar architecture. The purpose of the studied network is strongly different from typical applications of artificial neural networks. The main goal of the network was to store information (even by overfitting the network) rather than some form of generalization that allows computation for unknown cases. Therefore, the authors primarily investigated in the ability of the layer-based LSTM network to store nonlinear time series data. The analyses presented in this paper are an extension of the issues presented in the paper entitled “Model of the Austenite Decomposition during Cooling of the Medium Carbon Steel Using LSTM Recurrent Neural Network”.  相似文献   
29.
我们采用RP-HPLC方法研究了SD纯系雄性大鼠冷适应期间脑垂体(P)、下丘脑(HT)和血浆(BP)生物活性肽变化。冷适应期间P、HT和BP肽类(MW≤30000)RP-HPLC图谱均出现一些新的肽洗脱峰。而且,所有这些肽类都能增强淋巴细胞(LC)转化活性。在P和HT肽类刺激下,脾LC[~3H]-TdR参入分别增加725 cpm(P<0.01)和1274 cpm(P<0.001)。将这些肽类进一步经Sep-Pack C_(18)柱纯化后仍分别增加[~3H]-TdR参入cpm值597(P<0.05)和333。这些结果表明了免疫系统(ImS)与神经内分泌系统(NES)双向调节环路的一个方面:NES作用于ImS。  相似文献   
30.
This paper focuses on the effect of gear steel on distortion due to phase transformation in carburizing and quenching. The carburizing and quenching process of C-rings under suspension was studied by using the finite element method based on the thermo-mechanical theory, considering phase transformation. The phase transformation kinetics parameters, depending on different carbon contents, were measured by Gleeble-3500. The distortion behavior of the carburized C-ring during the cooling stage was analyzed, as well as the carbon concentration distribution and martensite volume fractions. The accuracy of the simulation was also verified by comparing the experimental data with the simulated result of the distortion and microstructure. A reliable basis is provided for predicting the distortion mechanism of gear steels in carburizing and quenching.  相似文献   
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