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91.
PURPOSE: We investigate the patterns of failure in the treatment of glioblastoma(GBM) based on clinical target volume(CTV) margin size,dose delivered to the site of initial failure,and the use of temozolomide and intensity-modulated radiotherapy(IMRT).METHODS: Between August 2000 and May 2010,161 patients with GBM were treated with radiotherapy with or without concurrent temozolomide.Patients were treated with CTV expansions that ranged from 5 to 20 mm using a shrinking field technique.Patterns of failure and time to progression and overall survival were compared based on CTV margin,use of temozolomide,and use of IMRT.Kaplan Meier analysis was used to estimate survival times,and χ test was used for comparison of cohorts.RESULTS: For patients treated with 5-,10-,and 15-to 20-mm CTV,79%,77%,and 86% experienced failures in the 60 Gy volume,respectively.Forty-eight percent,55%,and 66% of patients with 5-,10-,and 15-to 20-mm CTV experienced failures in the 46 Gy volume,respectively.There was no statistical difference between patients treated with 5-,10-,15-to 20-mm margins with regard to 60 Gy failure(P=0.76),46 Gy failure(P=0.51),or marginal failure(P=0.73).Eighty percent of patients receiving temozolomide experienced failures in the 60 Gy volume.There was no increased likelihood of marginal failures in patients receiving IMRT(P =0.97).CONCLUSIONS: Modern treatment techniques including use of concurrent temozolmide,limited CTV margin size,and IMRT have not greatly changed the patterns of failure of GBM.  相似文献   
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BACKGROUND: Cellular immunity has been implicated in periodontal destruction for over 25 years. Studies in the 1970s used lymphocyte transformation and lympho-kine assays to establish a role for cell-mediated mechanisms in periodontal disease. lmmunohistological studies subsequently showed that the formation of gingivitis followed a similar pattern to the formation of a delayed type hypersensitivity reaction. Further functional studies suggested that a T cell/macrophage immunoregulatory imbalance may exist locally in the periodontitis lesion and that this imbalance may be antigen specific. RECENT EVIDENCE: More recently, T cell subsets have been dichotomised on the basis of their cytokine profiles. In general, Thl cells produce IL-2 and IFN-gamma while Th2 cells produce IL-4, IL-5 and IL-6. The major function of Th l cells is to mediate delayed type hypersensitivity. In contrast the major function of Th2 cells is to provide B cell help.
HYPOTHESIS: A model for periodontal disease has now been developed based on this functional dichotomy which provides a framework for the study of cytokine profiles in periodontal disease. Early studies in this context have demonstrated a higher proportion of IL-4 producing cells in periodontitis tissues suggesting a role for Th2 cells in the progressive lesion. Clonal studies have shown that the selection of a particular cytokine profile is not antigen dependent and that differences may be due to the host susceptibility although this remains to be determined.
CONCLUSION: These emerging data clearly establish a role for cell-mediated mechanisms in the control of periodontal destruction and raise the possibility that in the future cytokine therapy for the treatment of periodontal disease in susceptible subjects may become a viable option.  相似文献   
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IntroductionAdolescents and young people comprise a growing proportion of new HIV infections globally, yet current approaches do not effectively engage this group, and adolescent HIV‐related outcomes are the poorest among all age groups. Providing psychosocial interventions incorporating psychological, social, and/or behavioural approaches offer a potential pathway to improve engagement in care and health and behavioural outcomes among adolescents and young people living with HIV (AYPLHIV).MethodsA systematic search of all peer‐reviewed papers published between January 2000 and July 2020 was conducted through four electronic databases (Cochrane Library, PsycINFO, PubMed and Scopus). We included randomized controlled trials evaluating psychosocial interventions aimed at improving engagement in care and health and behavioural outcomes of AYPLHIV aged 10 to 24 years.Results and discussionThirty relevant studies were identified. Studies took place in the United States (n = 18, 60%), sub‐Saharan Africa (Nigeria, South Africa, Uganda, Zambia, Zimbabwe) and Southeast Asia (Thailand). Outcomes of interest included adherence to antiretroviral therapy (ART), ART knowledge, viral load data, sexual risk behaviours, sexual risk knowledge, retention in care and linkage to care. Overall, psychosocial interventions for AYPLHIV showed important, small‐to‐moderate effects on adherence to ART (SMD = 0.3907, 95% CI: 0.1059 to 0.6754, 21 studies, n = 2647) and viral load (SMD = −0.2607, 95% CI −04518 to −0.0696, 12 studies, n = 1566). The psychosocial interventions reviewed did not demonstrate significant impacts on retention in care (n = 8), sexual risk behaviours and knowledge (n = 13), viral suppression (n = 4), undetectable viral load (n = 5) or linkage to care (n = 1) among AYPLHIV. No studies measured transition to adult services. Effective interventions employed various approaches, including digital and lay health worker delivery, which hold promise for scaling interventions in the context of COVID‐19.ConclusionsThis review highlights the potential of psychosocial interventions in improving health outcomes in AYPLHIV. However, more research needs to be conducted on interventions that can effectively reduce sexual risk behaviours of AYPLHIV, as well as those that can strengthen engagement in care. Further investment is needed to ensure that these interventions are cost‐effective, sustainable and resilient in the face of resource constraints and global challenges such as the COVID‐19 pandemic.  相似文献   
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1背景与资料上世纪80和90年代,美国的医院和医生组织投入大量时间和资源进行机构重组,以实现提高组织效率、改善财务绩效水平、机构长期生存、承担社区责任和救治病人的目的。而机构重组的主要趋势是建立“有组织的服务提供体系”,包括建立横向的医院联合体,横向的医生联合体,以及纵向的医院与医生联合体等。到目前为止,在美国开展的大量研究对上述机构重组效果的认识莫衷一是。  相似文献   
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目的 用重组日本血吸虫22kD表膜蛋白(rSj22)免疫水牛,检测特异性IgG抗体的应答水平,并观察抗血吸虫的保护效果。方法 用抗原(rSj22)加佐剂(Quil-A)肌肉注射免疫水牛,以1000条日本血吸虫尾蚴攻击感染,感染后55d剖杀,计算减虫和减卵率,用免疫印斑和ELISA方法测定抗体反应。结果 免疫组每头牛血清均能特异地识别Quil-A对照组相比,减虫率仅8.5%肝卵EPG减少12.3%,粪卵EPG减少26.8%,但均无统计学意义,结论 用rSj22kD抗原免疫水牛诱导的特异性IgG抗体不能发挥免疫保护作用。  相似文献   
97.
In this article, we describe a relatively simple surgical option that we believe is indicated for use in cases of cervical incompetence. We discuss the advantages of this procedure to the surgeon and patient, and give details of 59 patients who have undergone this procedure one or more times over a 13-year period. A short review of the history of treatment of cervical incompetence and of recent trends for its management is also presented.  相似文献   
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注射用双黄连与几种抗生素联合体外抑菌活性的研究   总被引:11,自引:0,他引:11  
目的:探讨注射用双黄连与抗生素联合使用的临床意义。方法:参考中国药典抗生素微生物检定法,测定注射用双黄连与头孢拉定等6种抗生素配伍使用后对金葡菌及克雷白氏肺炎杆菌的抑菌圈直径的变化。结果:注射用双黄连与氨苄青霉素、普鲁卡因青霉素、头孢唑啉钠及红霉素配伍后对金葡萄的体外抑菌效果明显增强;与头孢拉定、头孢唑啉钠及普鲁卡因青霉素配伍后对克氏肺炎杆菌的体外抑菌效果有不同程度的增强。结论:对于不同的细菌感染  相似文献   
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