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91.
《肿瘤防治研究》2020,(7):517-523
Objective To investigate the correlation of rib 99mTc-MDP foci on whole-body bone scan with clinical variables and rib metastases in nasopharyngeal carcinoma(NPC) patients, and to screen the risk factors of rib metastases. Methods We retrospectively reviewed 312 NPC patients with rib 99mTc-MDP foci on wholebody bone scan. Chi-square test and logistic regression were performed to evaluate the correlation between clinical variables and rib metastases. Results In all 312 NPC patients, rib metastases were associated with T stage, skull base bone invasion, other bone metastasis, number of rib foci, lateral localization on rib and foci type (P<0.01), and the risk factors of rib metastasis included skull base bone invasion, other bone metastases, lateral localization on rib and foci type (P<0.05). In 176 patients with pure rib foci, rib metastases were closely related to T stage, skull base bone invasion, other bone metastasis, number of rib foci and lateral localization on rib (P<0.05), while only lobar distribution (P=0.029) was the effective risk factor. In 198 patients with single rib focus, rib metastases were affected by skull base bone invasion and foci type (P<0.01), while only foci type (P=0.000) was the effective risk factor. In all 566 rib foci, uptake level and localization on rib were the effective risk factors of rib metastases(P<0.01). Conclusion In NPC patients with rib foci on whole body bone scan, the effective risk factors of rib metastases include skull base bone invasion, other bone metastases, lateral localization on rib, foci type, uptake level and anterior and posterior localization on rib. Follow up should be the main way for the pure rib foci on unilateral ribs. For multiples rib foci on bilateral ribs or single rib focus combined with other bones foci, additional image modalities should be required to exclude bone metastasis. © 2020, CHINA RESEARCH ON PREVENTION AND TREATMENT. All rights reserved.  相似文献   
92.
With the application of magnetic resonance imaging (MRI)-guided photon therapy, the concept of combining real-time MRI guidance with proton therapy, namely, MRI-guided proton therapy (MRPT), has attracted widespread attention. It is expected that MRPT canmitigate the uncertaintiesduring the treatment of proton therapy to make full use of the physical advantages of protons. However, multiple electromagnetic interactions between proton therapy and MRI-guided systems may lead to mutual interference between the two systems. This article review the research progress on the MRPT system, aiming to provide certain reference for the design of MRPT system.  相似文献   
93.
目的 探讨接受新辅助放化疗的局部晚期食管鳞癌患者新辅助放疗剂量与病理完全缓解(pCR)的关系。方法 收集2017-2019年间在四川大学华西医院肿瘤中心经病理确诊为食管鳞癌并接受新辅助放化疗和手术的 116例局部晚期患者临床资料。116例患者中 40~45Gy组 80例,≥45Gy组 36例,分析两组术后pCR率。结果 全组患者的pCR率为38.8%(45/116),40~45Gy组与≥45Gy组的pCR率分别为44%(35/80)和28%(10/36)(P=0.105)。结论 术前新辅助采用较高的放疗剂量不增加局部晚期食管鳞癌的pCR率,有必要进行前瞻性的临床研究确定合适的新辅助放疗剂量。  相似文献   
94.
Racial/ethnic identity is contingent and arbitrary, yet it is commonly used to evaluate disease risk and treatment response. Drawing on open-ended interviews with patients and clinicians in two US clinics, we explore how racialized risk is conceptualized and how it impacts patient care and experience. We found that racial/ethnic risk was a common but poorly defined construct for both patients and clinicians, who intermingled concepts of genetics, biology, behavior, and culture, while disregarding historical or structural context. We argue that racializing risk embodies social power in marked and unmarked bodies, reinforcing inequality along racial lines and undermining equitable health care.  相似文献   
95.
ABSTRACT

Undocumented Mexican immigrants have had to regularly confront a prohibiting health care system despite alienation, marginalization, and the threat of deportation. In this article, I explore the impact of political exclusion and alienating discourses on the health habitus of undocumented Mexican mothers through the narrative of one mother, Marta Garza, who finds herself at the painful intersection of political and medical alienation. Marta’s narrative reflects an analytical framework that centers undocumented motherhood as a space of necessary resilience and strain, wherein she is forced to advocate for her children’s health despite prohibitive barriers and dangerous potential consequences.  相似文献   
96.
Medical interactions around reproduction are increasingly extending beyond the physician's office and onto the Internet, where negotiation with medical authority occurs in complex and dynamic ways. Recently, scholars have noted the Internet's potential for creating spaces where women can dialogue with and reconstruct medical authority, yet this growing body of work is overwhelming heteronormative. This paper thus interrogates how lesbian women use the Internet to challenge, deploy, and rework medical authority around reproduction while navigating the transition to parenthood. I draw from 17 online journals authored by lesbian couples during the conception, pregnancy, and birth of their first child, each spanning between 18 months and 2 years, in order to understand how the transition process unfolds over time. I argue that lesbian couples engage with medical authority when seeking affirmation and normalisation yet discard and publicly reject the heteronormative assumptions that accompany reproductive medicine. Further, they chart a new process that I term ‘constructing queer mother‐knowledge’, in which they critique and balance knowledges from institutionalised medicine, their own bodies, and their queer communities. With this new concept, I complicate understandings of lesbian mothers‐to‐be and their interactions with medical authority as they build subversive families.  相似文献   
97.
Applications of biomedical R&D currently imply substantial societal concerns. This paper explores, based on semi‐structured interviews with scientists in Norway, how biomedical researchers experience and tackle such concerns in their daily work. It shows how ritualised routine responses to dislocatory moments help maintain order in the daily work of the interviewed scientists; they do not address directly but instead smooth over concerns by a ritualised way of using ethics. This may foreclose substantive reflection and function as a stabiliser for ‘business as usual’. Overall, the current way of responding to concerns as described by the interviewees may contribute to a depoliticisation of important issues. The paper contributes to sociological work on ethics by linking it to recent discussions on Responsible Research and Innovation (RRI) and by the empirical research presented. The insights can also help improve science policies such as RRI.  相似文献   
98.
This paper proposes a ‘valuographic’ approach to diagnosis, exploring how values and valuation practices are implicated in the contested diagnostic category of idiopathic short stature (ISS). ISS describes children who are ‘abnormally’ short but do not have any other detectable pathology. In the USA growth‐promoting hormone therapy has been approved for ISS children, since 2003. However, no other jurisdiction has approved this treatment and the value of ISS as a diagnostic category remains disputed among healthcare professionals. Drawing on qualitative interviews with paediatric endocrinologists in the UK and the US, this study presents a historical snapshot illustrating how the problematisation of ISS as a diagnosis involved multiple registers of value including epistemic, economic and moral calculations of worth. Contestation of the diagnosis was not just about what counts but about what ought to be counted, as respondents’ accounts of ISS gave differential weight to a range of types of evidence and methods of assessment. Ultimately what was at stake was not just the value of increased height for short patients, but what it meant to properly practice paediatric endocrinology. Consideration is then given to how a valuographic approach can be applied to sociological studies of diagnosis more broadly.  相似文献   
99.
嗜肺军团菌是一种可以引起军团菌肺炎和庞蒂亚克热的兼性胞内病原菌,主要侵染阿米巴原虫和人类巨噬细胞。该菌在宿主胞内能依靠Dot/Icm IVB型分泌系统产生的效应蛋白成功逃避溶酶体的降解。本文主要对嗜肺军团菌的致病物质、胞内存活与增殖机制及其效应蛋白的生物学功能进行综述,详细介绍嗜肺军团菌的毒力因子与致病机制,为军团病防治的研究提供新思路,也为其他胞内病原菌所致感染性疾病的研究提供重要的借鉴意义。  相似文献   
100.
目的:以灰毡毛忍冬为材料,克隆对-香豆酸3-羟化酶(LmC3H1)基因,进行生物信息学和表达模式分析,结合绿原酸含量,研究推测灰毡毛忍冬LmC3H1基因的功能。方法:通过逆转录聚合酶链式反应(RT-PCR)和RACE技术克隆LmC3H1基因的全长c DNA序列,对该序列进行生物信息学分析,并利用实时荧光定量PCR(Real-time PCR)和HPLC分别测定灰毡毛忍冬茎、叶及不同花期花中LmC3H1的相对表达量及绿原酸含量。结果:克隆得LmC3H1(Gen Bank:MN177695)基因,开放阅读框(ORF)长度为1 533 bp,编码510个氨基酸,推测其分子式为C_(2618)H_(4134)N_(718)O_(727)S_(22),相对分子质量为58 005.32,等电点8.92,为亲水性蛋白,定位于叶绿体中,具有跨膜区域LLLIPAVLFLISLVYPLI,含有细胞色素P450的保守结构域CYTOCHROME_P450(422-433 aa);Real-time PCR结果显示,LmC3H1在灰毡毛忍冬茎、叶及不同花期花有不同程度的表达,其中在花发育阶段,白色花蕾期相对表达量最高,花蕾初期及白色开花期次之;白色花蕾期花与茎、叶比,花的相对表达量最高,叶的最低;HPLC结果显示,从绿白色花蕾期到金黄色开花期绿原酸含量呈上升趋势,金黄色开花期含量最高,不同器官中,花中绿原酸最高,茎最低。结论:克隆得到灰毡毛忍冬LmC3H1基因,推测LmC3H1可能参与灰毡毛忍冬花绿原酸的生物合成。该研究为进一步研究该基因的功能及探究灰毡毛忍冬绿原酸生物合成和调节机制提供了依据,同时为遗传改良灰毡毛忍冬品质奠定了基础。  相似文献   
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