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1.
In recent years, thermal ablation has played an increasingly important role in treating various tumors in the clinic. A practical thermochromic phantom model can provide a favorable platform for clinical thermotherapy training of young physicians or calibration and optimization of thermal devices without risk to animals or human participants. To date, many tissue-mimicking thermal phantoms have been developed and are well liked, especially the polyacrylamide gel (PAG)–based phantoms. This review summarizes the PAG-based phantoms in the field of thermotherapy, details their advantages and disadvantages and provides a direction for further optimization. The relevant physical parameters (such as electrical, acoustic, and thermal properties) of these phantoms are also presented in this review, which can assist operators in a deeper understanding of these phantoms and selection of the proper recipes for phantom fabrication.  相似文献   
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目的:了解2011-2017年四川省三州地区卫生人力资源配置现状,为三州地区卫生人力资源的合理配置提供参考。方法:利用千人卫生人力资源拥有量指标、基尼系数和卫生人力资源密度指数(HRDI)分析卫生人力资源配置现状及其公平性。结果:三州地区千人卫生人力资源拥有量呈增长趋势;基尼系数大多超过0.4,仅护士按人口分布的基尼系数较小;卫生人力资源密度指数较小,需要量、缺乏量及缺乏比例均较大。结论:三州地区卫生人力得到一定程度改善;但配置公平性较差,尤其按地理、经济分布很不均衡;医护人员短缺,需要重点投入。  相似文献   
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内脏利什曼病是全球被忽视的传染病之一,危害严重。而利什曼原虫-人类免疫缺陷病毒(human immunodeficiency virus,HIV)合并感染对流行地区造成的威胁更甚。利什曼原虫与HIV存在相互作用,合并感染者在临床表现、诊断及治疗方面具有一定特殊性,其病死率及复发率均高于HIV阴性的内脏利什曼病患者。本文对利什曼原虫-HIV合并感染患者的临床表现、诊断和治疗进展进行综述。  相似文献   
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《Vaccine》2021,39(45):6601-6613
AKS-452 is a biologically-engineered vaccine comprising an Fc fusion protein of the SARS-CoV-2 viral spike protein receptor binding domain antigen (Ag) and human IgG1 Fc (SP/RBD-Fc) in clinical development for the induction and augmentation of neutralizing IgG titers against SARS-CoV-2 viral infection to address the COVID-19 pandemic. The Fc moiety is designed to enhance immunogenicity by increasing uptake via Fc-receptors (FcγR) on Ag-presenting cells (APCs) and prolonging exposure due to neonatal Fc receptor (FcRn) recycling. AKS-452 induced approximately 20-fold greater neutralizing IgG titers in mice relative to those induced by SP/RBD without the Fc moiety and induced comparable long-term neutralizing titers with a single dose vs. two doses. To further enhance immunogenicity, AKS-452 was evaluated in formulations containing a panel of adjuvants in which the water-in-oil adjuvant, Montanide™ ISA 720, enhanced neutralizing IgG titers by approximately 7-fold after one and two doses in mice, including the neutralization of live SARS-CoV-2 virus infection of VERO-E6 cells. Furthermore, ISA 720-adjuvanted AKS-452 was immunogenic in rabbits and non-human primates (NHPs) and protected from infection and clinical symptoms with live SARS-CoV-2 virus in NHPs (USA-WA1/2020 viral strain) and the K18 human ACE2-trangenic (K18-huACE2-Tg) mouse (South African B.1.351 viral variant). These preclinical studies support the initiation of Phase I clinical studies with adjuvanted AKS-452 with the expectation that this room-temperature stable, Fc-fusion subunit vaccine can be rapidly and inexpensively manufactured to provide billions of doses per year especially in regions where the cold-chain is difficult to maintain.  相似文献   
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目的:应用磁共振成像(MRI)技术探究空气细颗粒物PM2.5暴露水平对健康成年人大脑灰质体积(GMV)和认知功能的影响。方法:选取487例健康成人,采集一般人口学信息及详细居住信息,并根据居住信息获取各受试近6个月和8岁~15岁期间的PM2.5暴露水平,对所有研究对象完成高分辨率结构MRI扫描,使用中文版精神分裂症认知功能成套测验-共识版(MCCB)进行认知测查,使用相关和回归分析探索空气PM2.5暴露水平与GMV和认知功能的关联。结果:近6个月PM2.5暴露水平与大脑右侧额下回三角部(brodmann分区[BA] 45)和右侧颞中回(BA 22)GMV存在负性关联(FWE校正,P<0.05,团块>10体素);与MCCB认知评估的信息处理速度-连线测试(r=-0.17,P<0.01)和推理和问题解决-迷宫测验评分(r=-0.22,P<0.01)负相关。8~15岁时的累积空气PM2.5暴露量与左侧梭状回(BA 18)和右侧舌回(BA 17)GMV负相关(FWE校正,P<0.05,团块>10体素),且与信息处理速度-连线测试、推理和问题解决-迷宫测验评分...  相似文献   
8.
Most vaccines approved by regulatory bodies are administered via intramuscular or subcutaneous injections and have shortcomings, such as the risk of needle-associated blood infections, pain and swelling at the injection site. Orally administered vaccines are of interest, as they elicit both systemic and mucosal immunities, in which mucosal immunity would neutralize the mucosa invading pathogen before the onset of an infection. Hence, oral vaccination can eliminate the injection associated adverse effects and enhance the person's compliance. Conventional approaches to manufacturing oral vaccines, such as coacervation, spray drying, and membrane emulsification, tend to alter the structural proteins in vaccines that result from high temperature, organic and toxic solvents during production. Electrohydrodynamic processes, specifically electrospraying, could solve these challenges, as it also modulates antigen release and has a high loading efficiency. This review will highlight the mucosal immunity and biological basis of the gastrointestinal immune system, different oral vaccine delivery approaches, and the application of electrospraying in vaccines development.  相似文献   
9.

Background

Treatment of advanced anal squamous cell cancer (SCC) is usually with the combination of cisplatin and 5-fluorouracil, which is associated with heterogeneous responses across patients and significant toxicity. We examined the safety and efficacy of a modified schedule, FOLFCIS (leucovorin, fluorouracil, and cisplatin), and performed an integrated clinical and genomic analysis of anal SCC.

Patients and Methods

We reviewed all patients with advanced anal SCC receiving first-line FOLFCIS chemotherapy – essentially a FOLFOX (leucovorin, fluorouracil, and oxaliplatin) schedule with cisplatin substituted for oxaliplatin – in our institution between 2007 and 2017, and performed deep sequencing to identify genomic markers of response and key genomic drivers.

Results

Fifty-three patients with advanced anal SCC (48 metastatic; 5 unresectable, locally advanced) received first-line FOLFCIS during this period; all were platinum-naive. The response rate was 48% (95% confidence interval [CI], 32.6%-63%). With a median follow-up of 41.6 months, progression-free survival and overall survival were 7.1 months (95% CI, 4.4-8.6 months) and 22.1 months (95% CI, 16.9-28.1 months), respectively. Among all patients with advanced anal SCC that underwent sequencing during the study period, the most frequent genomic alterations consisted of chromosome 3q amplification (51%) and mutations in PIK3CA (29%) and KMT2D (22%). No genomic alteration correlated with response to platinum-containing treatment. Although there were few cases, patients with human papillomavirus-negative anal SCC did not appear to benefit from FOLFCIS, and all harbored distinct genomic profiles with TP53, TERT promoter, and CDKN2A mutations.

Conclusions

FOLFCIS appears effective and safe as first-line chemotherapy in patients with advanced anal SCC and represents an alternative treatment option for these patients.  相似文献   
10.
《Vaccine》2016,34(24):2663-2670
Human metapneumovirus (HMPV) is a major cause of morbidity and mortality from acute lower respiratory tract illness, with most individuals seropositive by age five. Despite the presence of neutralizing antibodies, secondary infections are common and can be severe in young, elderly, and immunocompromised persons. Preclinical vaccine studies for HMPV have suggested a need for a balanced antibody and T cell immune response to enhance protection and avoid lung immunopathology. We infected transgenic mice expressing human HLA-A*0201 with HMPV and used ELISPOT to screen overlapping and predicted epitope peptides. We identified six novel HLA-A2 restricted CD8+ T cell (TCD8) epitopes, with M39–47 (M39) immunodominant. Tetramer staining detected M39-specific TCD8 in lungs and spleen of HMPV-immune mice. Immunization with adjuvant-formulated M39 peptide reduced lung virus titers upon challenge. Finally, we show that TCD8 from HLA-A*0201 positive humans recognize M39 by IFNγ ELISPOT and tetramer staining. These results will facilitate HMPV vaccine development and human studies.  相似文献   
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