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目的:分析子野个数限值对宫颈癌固定野调强放疗(fixed-field intensity-modulated radiotherapy,ff-IMRT)计划的影响,寻求最优的子野个数限值。方法:选取10例接受ff-IMRT的宫颈癌患者,基于Monaco 5.11.03计划系统,以45 Gy/25 f处方剂量分别对同一患者设计8种ff-IMRT计划(ff-IMRT计划依据子野个数限值命名,子野个数限值分别为40、60、70、80、100、120、130、150),采用SPSS 20.0软件比较除plan100之外7个ff-IMRT计划与plan100剂量学参数、优化时间和治疗参数的差异。结果:8种ff-IMRT计划归一化后,plan40和plan60的D2%、Dmin、CI和HI均劣于plan100(P<0.05)。8种ff-IMRT计划均能较好保护危及器官(organ at risk,OAR)和正常组织。plan40小肠V45;plan40和plan60小肠D2cc,直肠、膀胱V45、D40%,两侧股骨头V40和正常组织 V35、V40均高于plan100(P<0.05)。plan40和plan60优化时间、治疗参数均优于plan100(P<0.05);plan120、plan130和plan150子野面积、子野个数(51~150 cm2和>150 cm2)和出束时间均劣于plan100(P<0.05)。结论:子野个数限值为70~100时,ff-IMRT计划能兼顾剂量学参数满足临床要求、优化时间和治疗参数最优化,建议在设计宫颈癌ff-IMRT计划时在该范围内设置子野个数限值。  相似文献   
3.
胡依    闵淑慧  郭芮绮  成晓芬  李贝 《现代预防医学》2022,(22):4112-4118
目的 了解流动老人基本公共卫生服务利用情况,以及社会融合对基本公共卫生服务利用的影响。方法 于2021年7—12月,采用方便抽样的方法,抽取广州市、深圳市、江门市452名流动老人进行问卷调查。采用二元logistic回归模型分析流动老人社会融合对建立健康档案、接受健康教育和老年人健康管理之间的影响。结果 在452名流动老人中,60.8%建立了居民健康档案,接受过健康教育和老年人健康管理的分别有64.4%和60.0%。Logistic分析结果显示,流动老人的居民健康档案行为受到月消费水平(B = 0.368,P<0.05)、社区文体活动参与程度(B = 0.362,P<0.01)、居留意愿(B = 0.408,P<0.001)、年龄(B = - 0. 513,P<0.01)、户籍类型(B = 0.742,P<0.01)、流动类型(B = - 0.539,P<0.05)等变量的影响;健康教育服务利用行为受到社区文体活动参与程度(B = 0.354,P<0.01)、年龄(B = - 0.411,P<0.05)、户籍类型(B = 0.561,P<0.05)的影响;老年人健康管理服务利用行为受到社区文体活动参与程度(B = 0.291,P<0.01)、居留意愿(B = 0.239,P<0.05)、年龄(B = - 0.474,P<0.05)、流动类型(B = - 0.471,P<0.05)、流动时间(B = 0.225,P<0.05)、流动目的(B = 0.328,P<0.01)的影响。结论 流动老人基本公共卫生服务利用率较低,社会融合会对流动老人的基本公共卫生服务利用产生积极影响。可以通过提高流动老人获得基本公共卫生服务的能力和社会融合水平来促进流动老人的基本公共卫生服务利用,从而实现基本公共服务均等化。  相似文献   
4.
PurposeTo study, from a U.S. payer’s perspective, the economic consequences of drug-coated balloon (DCB) versus standard percutaneous transluminal angioplasty (PTA) use for the treatment of stenotic lesions in dysfunctional hemodialysis arteriovenous fistulae.Materials and MethodsCost differences between DCBs and PTA at year 1 and beyond were calculated via 2 methods. The first approach used the mean absolute number of trial-observed access circuit reinterventions through 12 months (0.65 ± 1.05 vs 1.05 ± 1.18 events per patient for DCBs and PTA, respectively) and projected treatment outcomes to 3 years. The second approach was based on the trial-observed access circuit primary patency rates at 12 months (53.8% vs 32.4%) and calculated the cost difference on the basis of previously published Medicare cost for patients who maintained or did not maintain primary patency. Assumptions regarding DCB device prices were tested in sensitivity analyses, and the numbers needed to treat were calculated.ResultsUsing the absolute number of access circuit reinterventions approach, the DCB strategy resulted in an estimated per-patient savings of $1,632 at 1 year and $4,263 at 3 years before considering the DCB device cost. The access circuit primary patency approach was associated with a per-patient cost savings of $2,152 at 1 year and $3,894 at 2.5 years of follow-up. At the theoretical DCB device reimbursement of $1,800, savings were $1,680 and $2,049 at 2.5 and 3 years, respectively. The one-year NNT of DCB compared to PTA was 2.48.ConclusionsEndovascular therapy for arteriovenous access stenosis with the IN.PACT AV DCB can be expected to be cost-saving if longer follow-up data confirm its clinical effectiveness.  相似文献   
5.
线上一流课程作为一种新型的教学课堂模式,其建设与推广不仅使教师的教和学生的学呈现多元化,而且也使教师的教学和研究水平、学生的学习兴趣和能力得到了有效提升。本团队建设与推广的国家级首批线上一流课程免疫学基础与病原生物学已经完成6个学期的运行,累计学习人数40 395人,累计选课学校84所。本文从建设背景与建设目标、整体框架与建设资源、实施过程与推广应用、教学运行与互动、教学考核与评价、思考和展望等6个方面总结该课程的建设与推广情况。  相似文献   
6.
【目的】 在“中国科技期刊卓越行动计划”实施三周年之际,有必要对我国科技期刊2035年迈入“世界第一方阵”目标的具体任务进行重新审视和预判,以进一步明确发展方向,动态调整推进思路。【方法】 采用国内外科技期刊、科技论文、科技期刊评价成果的系统性发展数据对科技期刊“世界第一方阵” 国家(或地区)在高水平科技期刊数量与质量层面的入围标准进行界定,在深入总结现有基础和优势的同时,对我国科技期刊综合实力与“世界第一方阵”国家(或地区)的现实差距进行逐一梳理和剖析,并对实现目标的可行性和推进思路进行研判和设计。【结果】 必须继续加强高水平英文科技期刊创办和培育力度、持续加大优秀中文科技期刊的建设强度、快速推进国内外科技期刊论文等质同效评价制度的建设与引导,并积极探索建立科学家和科研机构办好一流科技期刊的责任制度和贡献激励机制、创新发展编辑人才队伍培养与激励管理思路、深入实践灵活多样的期刊出版市场资本运作模式、稳步推进期刊出版市场机制和管理制度改革,为我国科技期刊事业的高质量发展提速增效。【结论】 虽然当前阶段目标任务艰巨,但迈入“世界第一方阵”未来可期。  相似文献   
7.
目的 探究血清碱性成纤维细胞生长因子(bFGF)、血管内皮生长因子(VEGF) 与宫颈癌化疗敏感性及预后的关系。方法 选取2017年1月~2019年3月在浙江省台州医院确诊的62例宫颈癌患者(宫颈癌组)及体检健康者62例(对照组),宫颈癌患者进行化疗治疗。分别检测宫颈癌组化疗前及化疗18周后、对照组健康体检时血清bFGF、VEGF水平,随访2年统计患者生存情况,分析宫颈癌患者化疗前血清bFGF、VEGF水平与临床病理参数及预后的关系。结果 62例宫颈癌患者化疗后,完全缓解49例(79.03 %),部分缓解9例(14.52 %),疾病稳定0例(0.00%),病情进展4例(6.45 %),总有效率为93.55 %。宫颈癌组化疗前血清bFGF、VEGF水平均显著高于对照组(P<0.05)。Ⅱ A、Ⅱ B、Ⅲ A、Ⅲ B期宫颈癌患者化疗前血清bFGF、VEGF水平依次升高(P<0.05);低、中、高分化宫颈癌患者化疗前血清bFGF、VEGF水平依次降低(P<0.05);有淋巴结转移的宫颈癌患者化疗前血清bFGF、VEGF水平均显著高于无淋巴结转移患者(P<0.05)。化疗前和化疗18周后完全缓解、部分缓解、病情进展患者血清bFGF、VEGF水平均依次升高(P<0.05),与化疗前比较,部分缓解患者化疗18周后血清bFGF、VEGF水平均降低(P<0.05)。bFGF、VEGF低水平组生存率分别显著高于bFGF、VEGF高水平组(P<0.05)。结论 宫颈癌患者化疗前血清bFGF、VEGF水平呈高表达,二者水平与宫颈癌化疗敏感性及预后密切相关,血清bFGF、VEGF高水平患者预后较差,低水平患者预后较好。  相似文献   
8.
ObjectiveTo explore the hemostatic mechanism of Jianpi Yiqi Shexue decoction (JYSD) by regulating vascular factors in an immune thrombocytopenia (ITP) mouse model.MethodsAn ITP mouse model was established by the passive-immune modeling method, and interventional drugs used were prednisone tablets and JYSD. The platelet count; vascular activity–related factors vWF, VCAM-1, and TM; and VEGF and bFGF were used as observational indicators.ResultsOn the 8th day of administration, compared with the model group, platelet counts in the prednisone and JYSD groups increased (both P < .001). Compared with the control group, the levels of vWF, VCAM-1, and TM in the other groups were lower (all P < .05). The VCAM-1 level in the JYSD group was higher than that in the prednisone group (P = .012), but without significant difference compared with the model group (P = .051). The TM level in the JYSD group was the lowest (vs. the model group, P = .047; vs. the prednisone group, P = .006). Compared with the control group, the IOD values of VEGF and bFGF in the other three groups were lower (all P < .01). The IOD values of VEGF in the prednisone and JYSD groups were both higher than those in the model group (P = .002 and P < .001, respectively). The IOD values of bFGF among the model, prednisone, and JYSD groups were not statistically significant (P > .05).ConclusionA vascular factor disorder is involved in the pathogenesis of ITP. JYSD can increase the platelet count, upregulate VEGF expression, and reduce the TM level. JYSD has the same effect as prednisone tablets in regulating platelet, vWF, VEGF, and bFGF, with a stronger effect in normalizing VCAM-1 and TM levels. The hemostatic mechanism of JYSD is closely related to the effective balance of vascular factors.  相似文献   
9.
Sperm characteristics, such as sperm morphology and sperm morphometry are important in assessing sperm quality. This is especially important for the management and conservation of endangered and exotic species, like the Florida manatee, where information of this nature is extremely limited. In this study, we fill this knowledge gap to better understand the reproductive physiology of Florida manatees by conducting the first extensive analysis of sperm morphometry and ultrastructure. Sperm were retrieved from the vas deferens of nine recently deceased Florida manatees. Computer-aided sperm morphology analysis (CASMA) was used for morphometric analysis and laser-scanning confocal microscopy and electron microscopy were used for structural and ultrastructural characterization. Our findings reveal new morphometric and structural data for the Florida manatee spermatozoon. Twelve morphometric features of Florida manatee sperm were quantified with some approximately 1.5–2 times larger than those previously reported. Ultrastructurally, the Florida manatee spermatozoon followed a mammalian structural pattern with an ovate-shaped head, midpiece containing 84–90 mitochondria, and a flagellum. However, unique ultrastructural features were identified. Distinct, rectangular-like enlargement of four outer dense fibers surrounding the axoneme was evident, which may provide additional tensile strength to counteract the forces on sperm transiting the female reproductive tract. Likewise, strong localization of F-actin fibers within the midpiece may function to maintain sperm integrity within the female reproductive tract. These findings highlight the potential effects of sexual selective pressures on sperm size and structure in the Florida manatee and provide avenues for research on the occurrence of sperm competition in this species.  相似文献   
10.
IntroductionAnti-methicillin-resistant Staphylococcus aureus (MRSA) agents have different doses and administration periods. Thus, it is difficult to evaluate antimicrobial use (AMU) of anti-MRSA agents using defined daily doses per 1000 inhabitants per day (DID) or days of therapy per 1000 inhabitants per day (DOTID). This study aimed to evaluate the relationship between anti-MRSA agent use and resistant bacteria using the number of patients per 1000 inhabitants per day (PID) as an alternative index of AMU.MethodsAMU data for anti-MRSA agents were collected from the National Database of Health Insurance Claims and Specific Health Checkups (NDB) in 2016. The relationship between PID and DID or DOTID was evaluated. The number of patients with MRSA isolated was obtained from Japan Nosocomial Infections Surveillance, and their correlation with PID was analyzed. The rate of anti-MRSA agent use in each prefecture was investigated.ResultsPID showed a significant linear relationship with both DID and DOTID (all p < 0.0001). PID was significantly correlated with the number of patients with MRSA isolated. Additionally, the rate of anti-MRSA agent use was markedly different in each region.ConclusionsPID is not affected by doses and administration periods, and thus may be an alternative index for the selective pressure of antibiotics. Evaluating AMU using PID based on NDB data will help in the development of effective antimicrobial resistance measures.  相似文献   
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