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91.
2010年8月,美国心脏病学会基金会(ACCF)、美国心脏学会(AHA)共同发布了美国食品药品管理局(FDA)关于氯吡格雷的"盒装警告",主要针对医师和患者提出建议,其内容包括:通过检测药物基因型以明确患者氯吡格雷的代谢变化,患者不良反应的风险,基因多态性对氯吡格雷的代谢及临床影响。 相似文献
92.
����ϵͳ�����������ε���״�ͽ�չ 总被引:5,自引:0,他引:5
胆道系统恶性肿瘤包括胆管癌和胆囊癌 ,前者主要指原发于肝内、肝门部和远端肝外胆管的恶性肿瘤。至今胆系肿瘤仍依TNM分类法分为 0~Ⅳ期。 0期 :为原位癌 ;Ⅰ期 :肿瘤局限于粘膜层、肌层 ;Ⅱ期 :出现局部浸润 ;Ⅲ期 :在Ⅰ或Ⅱ期基础上肿瘤累及邻近组织或肝十二指肠韧带上淋巴结 ;Ⅳ期 :出现肝脏等器官受累或远处转移或出现以下之一区域的淋巴结转移 ,如胰周、十二指肠周、肝门周、腹腔及肠系膜。1 诊断胆系恶性肿瘤的诊断 ,主要依靠临床表现、实验室检查以及影象学检查。临床表现特异性不强 ,其中最基本的表现为胆道梗阻症状 ,同时可… 相似文献
93.
目的:中性粒细胞粘附在缺血再灌注损伤中有非常重要的作用。本文用SD大鼠趾长屈肌缺血再灌注损伤模型,观察L一粘附素单抗LAM1—116在缺血再灌注损伤中的作用。方法:30只SD大鼠被均分为2组:LAM1—116组和生理盐水对照组。每只大鼠的一侧趾长屈肌作为正常对照,另外一侧进行 3 h缺血 4 h再灌注。结果:LAM1— 116组实验侧的髓过氧化物酶为正常的2倍(2.3±2.2),生理盐水对照组则为正常的28倍(27.5±11.7)(P<0.001);LAM1—116组的湿重比(1.10± 0.10)、疲劳肌力(77. 1%±12.1%)与对照组相比(分别为 1. 23± 0. 10和 49. 7%± 9 .3%)明显改善(P< 0.05);组织学上,LAM1—116组的中性粒细胞局部浸润显著减少,水肿减轻。结论:通过 L-粘附素单克隆抗体 LAM1— 116阻断 L-粘附素的功能,可以有效地降低中性粒细胞在再灌注肌肉中的浸润,防止组织水肿,从而改善肌肉的功能。 相似文献
94.
95.
Sara S Roscioni Bart GJ Dekkers Alwin G Prins Mark H Menzen Herman Meurs Martina Schmidt Harm Maarsingh 《British journal of pharmacology》2011,162(1):193-209
BACKGROUND AND PURPOSE
Changes in airway smooth muscle (ASM) phenotype may contribute to the pathogenesis of airway disease. Platelet-derived growth factor (PDGF) switches ASM from a contractile to a proliferative, hypo-contractile phenotype, a process requiring activation of extracellular signal-regulated kinase (ERK) and p70S6 Kinase (p70S6K). The effects of cAMP-elevating agents on these processes is unknown. Here, we investigated the effects of cAMP elevation by prostaglandin E2 (PGE2) and the activation of the cAMP effectors, protein kinase A (PKA) and exchange protein activated by cAMP (Epac) on PDGF-induced phenotype switching in bovine tracheal smooth muscle (BTSM).EXPERIMENTAL APPROACH
Effects of long-term treatment with the PGE2 analogue 16,16-dimethyl-PGE2, the selective Epac activator, 8-pCPT-2′-O-Me-cAMP and the selective PKA activator, 6-Bnz-cAMP were assessed on the induction of a hypo-contractile, proliferative BTSM phenotype and on activation of ERK and p70S6K, both induced by PDGF.KEY RESULTS
Treatment with 16,16-dimethyl-PGE2 inhibited PDGF-induced proliferation of BTSM cells and maintained BTSM strip contractility and contractile protein expression in the presence of PDGF. Activation of both Epac and PKA similarly prevented PDGF-induced phenotype switching and PDGF-induced activation of ERK. Interestingly, only PKA activation resulted in inhibition of PDGF-induced phosphorylation of p70S6K.CONCLUSIONS AND IMPLICATIONS
Our data indicate for the first time that both Epac and PKA regulated switching of ASM phenotype via differential inhibition of ERK and p70S6K pathways. These findings suggest that cAMP elevation may be beneficial in the treatment of long-term changes in airway disease. 相似文献96.
Paulsson AK McMullen KP Peiffer AM Hinson WH Kearns WT Johnson AJ Lesser GJ Ellis TL Tatter SB Debinski W Shaw EG Chan MD 《中国神经肿瘤杂志》2013,(1):52-52
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
97.
98.
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
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
99.
Christina A Laurenzi Stefani du Toit Wole Ameyan GJ MelendezTorres Tashmira Kara Amanda Brand Yeukai Chideya Nina Abrahams Melissa Bradshaw Daniel T Page Nathan Ford Nadia A SamAgudu Daniella Mark Marco Vitoria Martina Penazzato Nicola Willis Alice Armstrong Sarah Skeen 《Journal of the International AIDS Society》2021,24(8)
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
100.
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