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81.
目的 探讨动态增强磁共振(DCE-MRI)半定量参数与局部晚期鼻咽癌患者长期预后的关系,为局部晚期鼻咽癌患者预后寻找无创性的预测指标。方法 收集贵州省肿瘤医院2011年1月至2012年1月一项前瞻性临床研究的局部晚期鼻咽癌患者的临床信息,国际抗癌联盟(UICC)2010分期Ⅲ、ⅣA、ⅣB期,先行多西紫杉醇+顺铂+5''-氟尿嘧啶(TPF)方案时辰诱导化疗3周期;后予调强放疗(IMRT)同期紫杉醇化疗2周期。诱导化疗前均行DCE-MRI检查,并获取DCE-MRI相关半定量参数,将DCE-MRI相关半定量参数与同期放化疗结束的鼻咽病灶近期疗效进行相关性分析。结果 77例患者中,71例完成治疗并有长期完整随访信息,中位随访77个月(9~86个月),3年、5年OS分别为80.2%、67.6%;3年、5年PFS分别为73.2%、60.5%;同步放化疗结束鼻咽病灶近期疗效评价完全缓解(CR)组与部分缓解(PR)组之间的造影剂到达组织时间的差异具有统计学意义(t=0.537,P<0.05);单因素生存分析发现,造影剂到达组织时间短组的OS(χ2=3.982,P<0.05)和PFS(χ2=4.019,P<0.05)均高于造影剂到达组织时间长组;年龄≥ 45岁的患者OS(χ2=7.593,P<0.05)和PFS(χ2=5.624,P<0.05)明显低于年龄<45岁的患者。Cox多因素回归模型发现,临床分期晚(ⅣA、ⅣB期)(P=0.048)、年龄≥ 45岁(P=0.031)是鼻咽癌患者OS的独立不良预后因素;而造影剂到达组织时间长(P=0.018)、年龄≥ 45岁(P=0.004)、N(2~3期)分期晚(P=0.032)和强化峰值<3 000(P=0.005)则为鼻咽癌患者PFS的独立不良预后因素。结论 DCE-MRI参数造影剂到达组织时间可能作为局部晚期鼻咽癌患者预后可靠的影像学指标。 相似文献
82.
鼻分泌物及皮肤组织中麻风菌及其PGL-1抗原的检测 总被引:2,自引:0,他引:2
为了更好地理解麻风菌鼻携带在麻风病传播、维持中的作用,以及运用鼻携带检测来评价麻风病防治效果,比较了PCR和Dot-ELISA/ECL平行检测32例活动性麻风患者、13例愈后者和143名麻风家内接触者鼻分泌物及皮肤组织中的麻风菌及其PGL-1抗原。结果显示,Dot-ELISA/ECL具有较好的敏感性、特异性,是一项适用于现场研究的简便、快速、经济的麻风流行病学工具。此外,用于免疫学试验,GVHP是一种吸附性好,适合于检测粘膜分泌物抗原的载体。 相似文献
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84.
目的 构建个性化知识图谱技术和定性访谈法结合,进一步挖掘张忠德教授辨治间质性肺疾病临证特征与用药规律。方法 采用回顾性分析,系统收集张忠德教授广东省中医院门诊2010年8月至2020年8月治疗间质性肺疾病病历,按照诊断标准、纳入标准、排除标准,严格筛选后,通过广东省中医院大数据挖掘团队中医药大数据智能处理与知识服务系统进行数据挖掘分析,并通过多元化视觉定性访谈法,将定量与定性分析有效结合。结果 共筛选出347首方,共141味药物,常用药物频次 ≥ 84次的药物有10味,其中党参、麦芽、黄芪、紫菀、白术等为核心用药,通过症状与药物推理知识地图显示,党参、炒麦芽、黄芪、大枣、太子参、山萸肉、巴戟天等为主要治疗用药;临证遣方用药知识关联分析,得知咳嗽、耳鸣、心悸、水肿、头痛、胸闷、恶寒等为多见,针对咳嗽,首选紫苏子、橘红、桂枝等温肺降气通阳之品等;频繁聚集显示,常用药对炒麦芽-炒白术、黄芪-党参、黄精-菟丝子、前胡-紫菀、炙枇杷叶-浙贝母等;聚类分析结果得到4组关系密切的聚类新药物组合;以脾为中轴,肺肾共扶为主的“平调五脏论”,分期阶梯辨治间质性肺疾病。结论 张忠德教授认为间质性肺疾病,虚实夹杂为多见,应从肺、脾、肾着手,采用平调五脏论分期阶梯辨治,用药配伍精简,以和为贵,以平为期。 相似文献
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87.
Gen Zhang Liang Wu Aitao Tang Bo Weng Andrej Atrens Shida Ma Lei Liu Fusheng Pan 《RSC advances》2018,8(5):2248
In this work, anodized magnesium alloy AZ31 with and without boiling water sealing was pre-prepared, and then MgAl-layered double hydroxide (LDH) films were fabricated on it through hydrothermal chemical conversion of the pre-prepared anodic layer. The morphology, structure, and composition of the films were characterized by XRD, SEM, EDS, FT-IR, XPS and GDOES. It was found that the porosity of the films was reduced after in situ fabrication of the LDHs. The effects of boiling water sealing treatment on the anodized substrate were also discussed. Moreover, the polarization curve, EIS, and immersion tests showed that LDHs fabricated on the anodized substrate with boiling water sealing treatment exhibited a significant long period of protection for the substrate.In this work anodized magnesium alloy AZ31 with and without boiling water sealing was pre-prepared, and then MgAl-layered double hydroxide (LDH) films were fabricated on it through hydrothermal chemical conversion of the pre-prepared anodic layer. 相似文献
88.
89.
In this study, fluorescence of self-assembled multilayers (SAMs) of carbon dots (CDs) was found to be enhanced by graphene. The number of polyelectrolyte layers can be tuned to control the distance between CDs and graphene in SAMs. The enhanced fluorescence efficiency was found to be dependent on graphene concentration, degree of graphene reduction, and the distance between CDs and graphene surface. When graphene concentration and polyelectrolyte bilayer number were set to 0.005 mg mL−1 and 3 layers, respectively, fluorescence intensity of CDs could be increased up to 3.2 times. Tetracycline hydrochloride (Tc) could be detected by the established SAMs in the presence of graphene as the sensitivity was 2 orders higher than that of SAMs in the absence of graphene. Limit of detection of this sensing system was 0.9284 nM, which is 1–3 orders of magnitude lower than those of most of reported fluorescence sensors. This method could be successfully applied to detect trace Tc in milk samples.The fluorescence of carbon dots self-assembled multilayers (CDs SAMs) can be enhanced by graphene, the sensing sensitivity for tetracycline hydrochloride of CDs SAMs with graphene is two orders higher than that of SAMs without graphene. 相似文献
90.
Effects of medroxyprogesterone and estradiol on the recovery of spermatogenesis in irradiated rats 总被引:1,自引:0,他引:1
Shetty G Weng CC Bolden-Tiller OU Huhtaniemi I Handelsman DJ Meistrich ML 《Endocrinology》2004,145(10):4461-4469
Suppression of intratesticular testosterone (ITT) levels is required for spermatogenic recovery in rats after irradiation, but maintenance of peripheral testosterone (T) levels is important for many male functions. Considering the preservation of peripheral T while suppressing ITT, we tested the effects of a combination of a progestin, medroxyprogesterone acetate (MPA), plus T on spermatogenic recovery after irradiation, and compared its effects to those of T alone or T combined with estradiol (E2). Rats were given testicular irradiation (6 Gy) and treated during wk 3-7 after irradiation with MPA + T, or the individual steroids with or without GnRH antagonist (GnRH-ant), or GnRH-ant alone, or T + E2. Whereas GnRH-ant alone stimulated differentiation in 55% of tubules 13 wk after irradiation compared with 0% in irradiated-only rats, the addition of MPA reduced the percentage of tubules showing differentiation to 18%. However, T or MPA alone or the combination of the two induced germ cell differentiation in only 2-4% of tubules. In contrast, E2 stimulated differentiation in 88% of tubules, and T combined with E2 still resulted in differentiation in 30% of tubules. Although both MPA and E2 suppressed ITT levels to approximately 2% of control (2 ng/g testis), MPA was a less effective stimulator of spermatogenic recovery than E2 or GnRH-ant alone. MPA's function as a weak androgen was likely responsible for inhibiting spermatogenic recovery, as was the case for all other tested androgens. Thus, for clinical protection or restoration of spermatogenesis after radiation or chemotherapy by suppressing T production, MPA, at least in the doses used in the present study, is suboptimal. The combination of an estrogen with T appears to be most effective for stimulating such recovery. 相似文献