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181.
The present preliminary study was performed to find out stability of total prostate specific antigen (PSA) and free prostate specific antigen (FPSA) in serum of healthy males as well as in patients of benign and malignant disorders of prostate at various freezing and nonfreezing temperatures and at different duration of time. The results of our study indicated long-term stability of both the analytes in frozen serum. Serum total and free PSA were stable only for three to four days in regular refrigerators in unfrozen states. Clotted blood kept at room temperature (25°C–30°C) did not cause change in concentrations of both the analytes for twenty four hours.  相似文献   
182.
目的:通过端粒酶的数量变化来探讨瑞香狼毒提取物对肺癌细胞NCI-H446[H446]的抗肿瘤作用。方法:体外培养肺癌细胞NCI-H446[H446]细胞株,以不同浓度的瑞香狼毒提取物作用24h后,用荧光标记的方法定量检测端粒酶。结果:瑞香狼毒提取物作用人肺癌细胞提取物NCI-H446[H446]后,端粒酶的数量明显减少并呈现与剂量的正相关性。结论:瑞香狼毒提取物对肺癌细胞NCI-H446[H446]具有明显的抗肿瘤作用。  相似文献   
183.
乳腺癌是全球范围内严重威胁女性健康的主要恶性肿瘤,临床就诊患者的年龄普遍提前.如何有效的控制其发生和发展,做到早期发现,早期诊断,早期治疗,已经成为当务之急.乳腺自查,乳腺X线钼靶摄片,超声检查,MRI检查,CT检查,影像定位穿刺活检,乳头溢液检查都可提高乳腺癌的早期诊断率.  相似文献   
184.
185.
Recommendations for breast support, dynamic breast pain assessment, and implications for sports performance have been made within breast biomechanics research; however, these studies have been based upon short exercise protocols (2–5 min). The aim of this study was to investigate the effect of breast support on multiplanar breast kinematics over a 5-kilometre run. Ten female participants (34D or 32DD) conducted two 5-kilometre runs, in a low and high breast support. Relative multiplanar breast kinematics were averaged over five gait cycles at six intervals of a 5-kilometre run. Increases in multiplanar breast kinematics were reported from the start to the end of the run, with the greatest rate of increase in breast kinematics reported within the first two kilometres of running. The greatest relative increases in breast range of motion (34%), velocity (33%), and acceleration (41%) were reported in the superioinferior direction at the fifth kilometre (33 min of running) in the high breast support. Key findings suggest that the run distance, and therefore run duration, employed for both fundamental research and product validation protocols should be carefully considered and it is suggested that running protocols for assessing breast biomechanics should exceed 7 min.  相似文献   
186.
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   
187.
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   
188.
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   
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