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451.
乙型肝炎是严重威胁人类健康的三大世界性顽症之一,推行乙肝疫苗接种是预防和阻断乙型肝炎病毒感染的重要措施.分析了目前乙肝疫苗存在的伺题,介绍了1018 ISS佐剂疫苗、YIC治疗疫苗、单剂缓控释微球的情况,指出简化免疫程序、发展更有免疫效果甚至具有一定治疗作用的新型乙肝疫苗是未来的发展趋势. 相似文献
452.
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
453.
Sergey VTORUSHIN Anastasia DULESOVA Nadezhda KRAKHMAL 《Journal of Zhejiang University. Science. B》2022,23(8):617
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
454.
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