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511.
低氧诱导因子与乳腺癌转移   总被引:2,自引:0,他引:2  
概肿瘤,特别是实体瘤,其内部微环境处于一种低氧或缺氧的状态,肿瘤的这种低氧微环境将诱导活化低氧诱导因子(HIF-1)信号通路。HIF-1信号通路在乳腺癌的转移中发挥着重要的作用。乳腺癌的转移涉及肿瘤细胞的浸润、进入血管、通过血液循环迁移、到达远端毛细血管内壁、穿透血管壁进入新的器官以及在新的部位形成转移灶等步骤,过程非常复杂。本文重点围绕 HIF-1在转移各个步骤中的作用进行综述。  相似文献   
512.
概乳腺癌已居我国女性恶性肿瘤死亡率首位。近来研究表明,乳腺肿瘤组织内有少量具有自我更新和分化潜能的肿瘤干细胞,这些肿瘤干细胞在乳腺癌发生、发展、转移及复发过程中起关键作用。深入研究乳腺癌干细胞的调控机制对乳腺癌的预防和治疗具有十分重要意义。本文综合近期的研究成果,概括了表观遗传修饰和代谢重编程对上皮间质转化及乳腺癌干细胞的调控机制,且系统地分析与总结了表观遗传修饰、代谢重编程、上皮间质转化和乳腺癌干细胞之间的相互关系。  相似文献   
513.
目的:探讨血清糖类抗原CA199糖类抗原CA724癌胚抗原CEA在结直肠癌的TNM分期中的临床应用价值。方法:观察组结直肠癌患者100例与对照组同期非消化道肿瘤的住院病人100例,空腹抽取静脉血,采用罗氏公司E601电化学发光全自动免疫分析仪和罗氏原装试剂盒检测血清中CEA、CA199、CA724值。应用SPSS 17.0软件进行统计学处理,计量资料以均数±标准差f±s)表示,采用单因素方差分析进行统计,计数资料采用X-2检验,P0.05为差异有统计学意义。结果:在单项检测中,CEA的敏感率最高,达37%,且CEACA199CA724.在两项联合检测中CA199+CEA的敏感度最高达53%,三项联合检测敏感度达64%,在各种联合检测中最高。三项肿瘤标志物的阳性率和升高水平随肿瘤的TNM分期的增加而递增。结论:三项肿瘤标志物的单一检测敏感度较低,肿瘤标志的联合检测结直肠癌可以提高敏感性,以CEA+CA199+CA724的效果最好,CA199+CEA次之。CA199、CA724、CEA三项肿瘤标志物的阳性率及升高水平依肿瘤的TNM分期的增加呈递增趋势。  相似文献   
514.
This study quantifies racial/ethnic differences in Medicaid expenditures on psychotropic drugs among a national sample of children with suspected maltreatment. We linked 4,445 child participants in the National Survey of Child and Adolescent Well-Being (NSCAW) – consisting of children investigated for suspected abuse and neglect – to their Medicaid claims obtained from 36 states. We used propensity score matching to construct a comparison group of children without known child welfare involvement, and estimated two-part generalized linear models to examine differences in annual psychotropic drug expenditures per child between children of different races/ethnicities. When compared to a matched sample of children, African American and Latino children incur $292 and $144 less expenditures on psychotropic drugs, respectively, than white children. Among NSCAW children alone, African American children display $614 less spending on psychotropic drugs when compared to white children. Racial/ethnic differences in expenditures on psychotropic drugs occur among all children on Medicaid, but the differences are especially pronounced among African American children in contact with the child welfare system. These findings demonstrate that policymakers will need to pay special attention to the needs of children of color as Medicaid expansions proceed nationwide.  相似文献   
515.
乳腺癌是现代女性最常见的恶性肿瘤之一,X光照片是一种在乳腺癌普查中广泛采用的检测手段。由于医学影像噪声大不清晰,检测结果往往不尽人意。本文以数字乳房X片图像为对象,研究了提高微钙化点的对比度的基于小波变换的图像增强算法。小波变换在时频域的多分辨率具有良好的空间域和频率域局部化特性。实验证明,基于小波多分辨率分析在抑制噪声的同时能对图像进行有效增强,提高图像的对比度,使钙化点的显示更为明显,提高了图像中病灶重要特征的可视化。基于小波的图像去噪和增强算法作为医学诊断的辅助手段有极其重要的意义。  相似文献   
516.
According to the classification presented by Lehmann BD (2016), triple-negative breast cancer (TNBC) is a heterogeneous group of malignant tumors with four specific subtypes: basal-like (subtype 1 and subtype 2), mesenchymal, and luminal androgen receptor (LAR) subtypes. The basal-like subtypes of carcinomas predominate in this group, accounting for up to 80% of all cases. Despite the significantly lower proportions of mesenchymal and LAR variants in the group of breast carcinomas with a TNBC profile, such tumors are characterized by aggressive biological behavior. To this end, the LAR subtype is of particular interest, since the literature on such tumors presents different and even contradictory data concerning the disease course and prognosis. This review is devoted to the analysis of the relevant literature, reflecting the main results of studies on the molecular properties and clinical features of the disease course of LAR-type TNBC carcinomas.  相似文献   
517.
Tumor-associated bacteria (TAB) play a critically important role in regulating the microenvironment of a tumor, which consequently greatly deteriorates the therapeutic effects by chemo- and radiotherapy deactivation and, more considerably, leads to substantial immunosuppression. On the contrary, herein we propose a nanocatalytic tumor-immunotherapeutic modality based on the bacteria disintegration by bacteria-specific oxidative damage under magnetic hyperthermia for highly effective immune response activation-promoted tumor regression. A monodispersed and superparamagnetic nanocatalytic medicine modified by arginyl-glycyl-aspartic acid (RGD) and (3-carboxypropyl)triphenylphosphonium bromide (TPP), named as MNP-RGD-TPP herein, has been synthesized, which features selective accumulation at the TAB by the electrostatic affinity, enabling effective TAB disintegration by the nanocatalytic Fenton reaction producing abundant cytotoxic hydroxyl radicals in situ under alternating magnetic field-induced hyperthermia. More importantly, the lipopolysaccharide has been metabolically secreted from the destructed TAB as pathogen-associated molecular patterns (PAMPs) to M1-polarize tumor-associated macrophages (TAMs) and promote the maturation of dendritic cells (DCs) for innate immuno-response activation of TAMs, followed by cytotoxic T lymphocytes awakening under the PAMPs presentation by the mature DCs against tumor cells. The integrated innate and adaptive immunity activations based on this TAB-promoted nanocatalytic immunomedicine, instead of magnetic heating-induced hyperthermia or the released Fe2+/Fe3+ Fenton agent, has been found to achieve excellent therapeutic efficacy in an orthotopic colorectal cancer model, demonstrating the great potential of such an integrated immunity strategy in clinical tumor immunotherapy.  相似文献   
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