锻造液压机实验研究

分析了使用大流量比例阀作为主控阀的锻造液压机的加载与卸载特性,对影响液压机快速性和平稳性的因素进行了实验研究,提出了提高与改善液压机性能的具体措施。     

混合型调压室的涌浪计算

本文介绍了双室-差动混合型调压室涌浪计算的数学模型和相应的电算程序“TCP—ST—1”,所编程序具有通用性,不仅可用于计算混合型调压室的涌浪,也可计算各种常规调压室的涌浪。程序已在某工程实际应用,论证了程序的通用可靠性。     

外用重组人粒细胞-巨噬细胞刺激因子凝胶与注射用重组人生长激素联合应用对实验性烫伤动物的疗效

目的观察外用重组人粒细胞-巨噬细胞刺激因子(rhGM-CSF)凝胶与注射用重组人生长激素(rhGH)联合应用对实验性烫伤动物的疗效。方法将脱毛的Wistar大鼠背部皮肤浸入(85±1)℃恒温水浴中持续15s,造成深Ⅱ度烫伤。大鼠烫伤部位分别涂抹外用rhGM-CSF凝胶、易孚凝胶、美宝湿润烧伤膏、磺胺嘧啶银、医用凡士林膏,金因肽组用金因肽喷湿创面,rhGH组和GM+GH组在烫伤后24h开始皮下注射rhGH。各组每天给药1次,连续用药25d。每5d用透明硫酸纸描绘烫伤皮肤面积,并称重,计算烫伤皮肤愈合率;烫伤后6h、9d和25d,各组随机选取3只大鼠,对其烫伤创面进行病理学检查。结果从给药第10天开始,各给药组大鼠烫伤皮肤愈合率均比模型组明显提高;以GM+GH组最高。病理学观察显示,烫伤后25d,各给药组大鼠绝大多数创面表皮细胞增生明显,真皮层可见毛囊、皮脂腺腺体修复,GM+GH组炎细胞浸润不明显,模型组多见化脓性炎症改变,并见脓肿灶形成。结论各给药组均可减轻烫伤后炎症反应,促进烫伤皮肤愈合,对深Ⅱ度烫伤大鼠皮肤有明显治疗作用,其中以外用rhGM-CSF凝胶联合应用rhGH的治疗效果最好。     

Hormonal Responses to Susceptible,Intermediate, and Resistant Interactions in the Brassica napus–Leptosphaeria maculans Pathosystem

Hormone signaling plays a pivotal role in plant–microbe interactions. There are three major phytohormones in plant defense: salicylic acid (SA), jasmonic acid (JA), and ethylene (ET). The activation and trade-off of signaling between these three hormones likely determines the strength of plant defense in response to pathogens. Here, we describe the allocation of hormonal signaling in Brassica napus against the fungal pathogen Leptosphaeria maculans. Three B. napus genotypes (Westar, Surpass400, and 01-23-2-1) were inoculated with two L. maculans isolates (H75 8-1 and H77 7-2), subsequently exhibiting three levels of resistance: susceptible, intermediate, and resistant. Quantitative analyses suggest that the early activation of some SA-responsive genes, including WRKY70 and NPR1, contribute to an effective defense against L. maculans. The co-expression among factors responding to SA/ET/JA was also observed in the late stage of infection. The results of conjugated SA measurement also support that early SA activation plays a crucial role in durable resistance. Our results demonstrate the relationship between the onset patterns of certain hormone regulators and the effectiveness of the defense of B. napus against L. maculans.     

Clinical Significance of Tumor Infiltrating Lymphocytes in Association with Hormone Receptor Expression Patterns in Epithelial Ovarian Cancer

Hormone receptor expression patterns often correlate with infiltration of specific lymphocytes in tumors. Specifically, the presence of specific tumor-infiltrating lymphocytes (TILs) with particular hormone receptor expression is reportedly associated with breast cancer, however, this has not been revealed in epithelial ovarian cancer (EOC). Therefore, we investigated the association between hormone receptor expression and TILs in EOC. Here we found that ERα, AR, and GR expression increased in EOC, while PR was significantly reduced and ERβ expression showed a reduced trend compared to normal epithelium. Cluster analysis indicated poor disease-free survival (DFS) in AR+/GR+/PR+ subgroup (triple dominant group); while the Cox proportional-hazards model highlighted the triple dominant group as an independent prognostic factor for DFS. In addition, significant upregulation of FoxP3+ TILs, PD-1, and PD-L1 was observed in the triple dominant group compared to other groups. NanoString analyses further suggested that tumor necrosis factor (TNF) and/or NF-κB signaling pathways were activated with significant upregulation of RELA, MAP3K5, TNFAIP3, BCL2L1, RIPK1, TRAF2, PARP1, and AKT1 in the triple dominant EOC group. The triple dominant subgroup correlates with poor prognosis in EOC. Moreover, the TNF and/or NF-κB signaling pathways may be responsible for hormone-mediated inhibition of the immune microenvironment.     

Differential Effects of Fkbp4 and Fkbp5 on Regulation of the Proopiomelanocortin Gene in Murine AtT-20 Corticotroph Cells

The hypothalamic-pituitary-adrenal axis is stimulated in response to stress. When activated, it is suppressed by the negative feedback effect of glucocorticoids. Glucocorticoids directly inhibit proopiomelanocortin (Pomc) gene expression in the pituitary. Glucocorticoid signaling is mediated via glucocorticoid receptors, 11β-hydroxysteroid dehydrogenases, and the FK506-binding immunophilins, Fkbp4 and Fkbp5. Fkbp4 and Fkbp5 differentially regulate dynein interaction and nuclear translocation of the glucocorticoid receptor, resulting in modulation of the glucocorticoid action. Here, we explored the regulation of Fkbp4 and Fkbp5 genes and their proteins with dexamethasone, a major synthetic glucocorticoid drug, in murine AtT-20 corticotroph cells. To elucidate further roles of Fkbp4 and Fkbp5, we examined their effects on Pomc mRNA levels in corticotroph cells. Dexamethasone decreased Pomc mRNA levels as well as Fkpb4 mRNA levels in mouse corticotroph cells. Dexamethasone tended to decrease Fkbp4 protein levels, while it increased Fkpb5 mRNA and its protein levels. The dexamethasone-induced decreases in Pomc mRNA levels were partially canceled by Fkbp4 knockdown. Alternatively, Pomc mRNA levels were further decreased by Fkbp5 knockdown. Thus, Fkbp4 contributes to the negative feedback of glucocorticoids, and Fkbp5 reduces the efficiency of the glucocorticoid effect on Pomc gene expression in pituitary corticotroph cells.     

航空发动机喘振的研究与发展

针对航空发动机喘振的特殊情况,在总结现有研究成果的基础上,指出了目前发动机喘振研究的3个方向———稳定性研究、防喘控制研究和喘振故障诊断,分析了各自的研究现状和发展趋势,对发动机设计人员、工程技术人员和飞行人员全面把握喘振问题,具有一定的参考价值。     

螺旋式调压井运输通道下压力钢管安装工法

大湾水电站调压井设计方案为底坡i=13%,断面6m×6m城门洞形螺旋式,洞身长310m。为合理节约投资、节省工期,调压井底板混凝土浇筑后,即作为压力钢管安装运输通道使用。安装单位根据洞身变径、螺旋式特点,巧妙地运用卸车天锚、导向地锚配合卷扬机、滑车系统,顺利完成安装任务,解决了该工程压力钢管运输难题。其经验可为其他类似工程参考。     

海河防潮闸防御风暴潮对策探析

随着天津滨海新区经济的蓬勃发展,风暴潮防灾减灾工作日趋重要。回顾了1939年以来最严重的风暴潮灾害——1992年风暴潮灾害,分析了海河闸挡潮能力现状,针对1992年以来海河防潮闸风暴潮的特点,提出了对风暴潮预警进行实时跟踪、完善应急响应体系、加强养护和检查观测、加强与地方的协调联防等应对措施。     

北疆某引水式电站通过阻抗孔对调压室体型的优化设计

调压室是减小水锤压力传递的有效方法,调压室断面受托马稳定条件制约,阻抗孔直径是托马稳定断面的重要参数之一。通过对北疆某水电站调压室的稳定需求给出较合适的断面积,通过阻抗孔对调压室体型进行优化设计,主要涉及阻抗孔口尺寸、顶板、底板设计高程及运行工况等因素。