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51.
目的 :评价氯沙坦、福辛普利、氨氯地平对自发性高血压大鼠 (SHR)心肌细胞凋亡及左室重构的效应。方法 :将 40只 16周龄SHR随机分为氯沙坦治疗组 (SHR -L)、福辛普利治疗组 (SHR -F)、氨氯地平治疗组 (SHR -A)及空白对照组 (SHR -C)。采用末端脱氧核糖核苷酸转移酶介导dUTP缺口末端标记、放免及病理检查方法对SHR治疗 8周、16周心肌细胞凋亡指数 (APOI)、血浆和组织血管紧张素II(PAngII,MAngII)及左室重构指标检测。结果 :①各治疗组治疗 8周、16周收缩压均明显下降 ,组间差异无显著性 ;各治疗组左室重量 (LVW)、左室重量指数 (LVMI)均有显著性改善 ,SHR -F组治疗 16周较其他两组LVMI显著减低。②仅SHR -F组治疗 8周APOI显著性下降 ,治疗 16周各治疗组APOI均有显著下降 ,尤以SHR -F组下降明显。③SHR -L组治疗 8周及 16周PAngII,MAngII显著增加。SHR -F组治疗 8周MAngII显著下降 ,治疗 16周SHR -F ,SHR -A两组MAngII均明显下降 ,且前组较后组下降显著 ,但对PAngII无明显影响。结论 :3药物均能有效逆转心脏肥厚及抗心肌细胞凋亡 ,其中以福辛普利显著。上述作用可能是拮抗心肌组织肾素 -血管紧张素 -醛固酮系统的效应。 相似文献
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Christine M. Lin Ronald G. Gill Borna Mehrad 《American journal of transplantation》2021,21(11):3550-3560
Chronic rejection is among the most pressing clinical challenges in solid organ transplantation. Interestingly, in a mouse model of heterotopic heart transplantation, antibody-dependent, natural killer (NK) cell-mediated chronic cardiac allograft vasculopathy occurs in some donor–recipient strain combinations, but not others. In this study, we sought to identify the mechanism underlying this unexplained phenomenon. Cardiac allografts from major histocompatibility complex (MHC) mismatched donors were transplanted into immune-deficient C57Bl/6.rag−/− recipients, followed by administration of a monoclonal antibody against the donor MHC class I antigen. We found marked allograft vasculopathy in hearts from C3H donors, but near-complete protection of BALB/c allografts from injury. We found no difference in recipient NK cell phenotype or intrinsic responsiveness to activating signals between recipients of C3H versus BALB/c allografts. However, cardiac endothelial cells from C3H allografts showed an approximately twofold higher expression of Rae-1, an activating ligand of the NK cell receptor natural killer group 2D (NKG2D). Importantly, the administration of a neutralizing antibody against NKG2D abrogated the development of allograft vasculopathy in recipients of C3H allografts, even in the presence of donor-specific antibodies. Therefore, the activating NK cell receptor NKG2D is necessary in this model of chronic cardiac allograft vasculopathy, and strain-dependent expression of NK activating ligands correlates with the development of this disease. 相似文献
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Gayathri Embuldeniya Jennifer Gutberg Walter P. Wodchis 《Health policy (Amsterdam, Netherlands)》2021,125(1):83-89
Purpose/settingTo encourage clinical and financial efficiency, the Canadian province of Ontario initiated an integrated care program – Integrated Funding Models (IFMs) that required collaboration and coordination across acute and post-acute care sectors. This research shows how program implementers went beyond policy-makers’ original designs, to make integrated care sustainable for chronic diseases.MethodsForty-five interviews were conducted with program participants at three chronic disease programs, as well as with policymakers. Interviews were conducted over two phases; during early implementation in 2016, and as programs matured in 2018. Data were analyzed through a cultural constructivist lens to understand how participants shaped programs.FindingsParticipants desired greater accountability and control. Participants in the first program wanted localized control over decision-making. In the second, participants initiated greater control over financial uncertainty. In the third program, hospital participants sought greater control over community care. Participants across programs simultaneously wanted integrated care to be expanded holistically, spatially, and temporally for patients, extending the length of care, and expanding the spaces in which care was provided. Findings also suggest a gap between program implementers’ and policymakers’ conceptualizations of integrated care.ConclusionThis work shows how IFMs were reimagined in ways that transcended their original conceptualization as spatially and temporally delimited initiatives aimed at improving coordination and efficiency. It has practical implications for those facing sustainability challenges in other contexts. 相似文献
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肺音信号的自回归谱谱阵分析 总被引:3,自引:0,他引:3
本文应用自回归模型方法研究了各种肺音信号的AR谱谱阵,并与傅里叶功率谱谱阵作了对比,探讨了两种谱阵的特点与差异,实验结果表明:肺泡呼吸音AR模型阶次为6阶,气管音AR模型阶次为14阶,哮鸣音与喘鸣音的AR模型阶次分别为12阶与6阶,正常呼吸音(肺泡呼吸音与气管音)功率谱为连续谱,异常连续性肺音(哮鸣音与喘鸣音)功率谱为离散线状谱,音肺信号谱阵方法可显示出肺音的时变特性,有利于对肺音作动态分析。 相似文献
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Kitchen LW Ross JA Hernandez JE Zarraga AL Mather FJ 《International journal of antimicrobial agents》1993,2(4):237-246
Other researchers have found that diethylcarbamazine (DEC) is effective treatment for filariasis despite a lack of demonstrated in vitro antifilarial activity. The results of our previous investigations using feline and murine leukemia virus models encouraged us to investigate the use of DEC with other infections. In our current experiments, DEC treatment was associated with lower brain fungal burden in fluconazole-treated mice following intravenous injection of Aspergillus fumigatus or increasing numbers of Cryptococcus neoformans organisms, and lower brain and kidney levels of Candida albicans following intravenous injection of increasing numbers of C. albicans. Further investigation of combined DEC and fluconazole treatment of fungal infections is warranted. 相似文献