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991.
影像设备电路板测试与故障诊断之系统实现   总被引:3,自引:0,他引:3  
大型医学影像设备是医院中的贵重设备,其中不少进口设备的维护修理的技术难度较高,医院每年花费在医学影像设备上的维护修理费是非常之大。本文从建立国内的维修力量着眼,研讨医学影像设备维修方法。  相似文献   
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Clear cell renal cell carcinoma (ccRCC) is the most common subtype of renal cell carcinoma and has the highest mortality rate. For metastatic RCC, systemic drug therapy is the most important method in addition to surgical tumor reduction. In recent years, tyrosine kinase inhibitors (TKIs) targeting the angiogenesis have been applied to treat ccRCC and achieved profound therapeutic effects. It has been reported that most patients receiving antiangiogenic therapy will develop resistance within 15 months. The mechanism of resistance to targeted therapy is extremely complex and has not been clarified. Ovarian tumor-associated protease domain-containing proteins (OTUDs) belonging to DUBs play a critical role in the tumorigenesis of solid tumors. However, the specific role of OTUDs in ccRCC is still elusive. Here, we investigated the clinicopathological role of OTUD family members in ccRCC. We demonstrated that OTUD1 was downregulated in renal cancer and involved in the poor prognosis of renal cancer. Then, we showed that OTUD1 inhibits cancer cell growth. Moreover, analysis of OTUD1 RNA-seq data indicated that OTUD1 inhibition triggers the AKT and NF-kappa B pathways in renal cancer cells. Furthermore, OTUD1 interacts with PTEN and regulates its stability. Subsequently, we revealed that downregulation of OTUD1 contributes to the sensitivity of renal cancer cells to TKIs, and this effect was blocked by TNF/NF-kappa B inhibitors and AKT inhibitors. Thus, we identified that the OTUD1-PTEN axis suppresses tumor growth and regulates the resistance of renal cancer to TKIs.  相似文献   
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996.
拟菱纹叶蝉属一新种记述(半翅目:叶蝉科:殃叶蝉亚科)   总被引:1,自引:0,他引:1  
记述拟菱纹叶蝉属HishimonoidesIshihara1新种,即苗岭拟菱纹叶蝉Hishimonoidesmiaolingensis,sp.nov.。模式标本保存于贵州大学昆虫研究所。  相似文献   
997.
为了解成都地区木芙蓉(Hibiscus mutabilis)品种间的亲缘关系,采用扫描电镜观察了19个木芙蓉品种的花粉显微结构,并探讨其分类学意义.结果表明,19个木芙蓉品种的花粉均为大粒,主要为圆球形,具散孔,外壁纹饰均为刺状纹饰,表面具有颗粒状突起.木芙蓉品种间在花粉粒大小、外壁纹饰上具有一定差异,可以作为品种分类...  相似文献   
998.
Diabetic cognitive impairment (DCI) is a common diabetic complication with hallmarks of loss of learning ability and disorders of memory and behavior. Glucocorticoid receptor (GR) dysfunction is a main reason for neuronal impairment in brain of diabetic patients. Here, we determined that ipriflavone (IP) a clinical anti‐osteoporosis drug functioned as a non‐steroidal GR antagonist and efficiently ameliorated learning and memory dysfunction in both type 1 and 2 diabetic mice. The underlying mechanism has been intensively investigated by assay against the diabetic mice with GR‐specific knockdown in the brain by injection of adeno‐associated virus (AAV)‐ePHP‐siGR. IP suppressed tau hyperphosphorylation through GR/PI3K/AKT/GSK3β pathway, alleviated neuronal inflammation through GR/NF‐κB/NLRP3/ASC/Caspase‐1 pathway, and protected against synaptic impairment through GR/CREB/BDNF pathway. To our knowledge, our work might be the first to expound the detailed mechanism underlying the amelioration of non‐steroidal GR antagonist on DCI‐like pathology in mice and report the potential of IP in treatment of DCI.  相似文献   
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1000.
Polycystic ovarian syndrome (PCOS) is one of the most prevalent endocrinopathies and the leading cause of anovulatory infertility, but its pathogenesis remains elusive. Although HB-EGF is involved in ovarian cancer progression, there is still no clarity about its relevance with PCOS. The present study exhibited that abundant HB-EGF was noted in follicular fluid from PCOS women, where it might induce the granulosa cells (GCs) production of more estrogen via the elevation of CYP19A1 expression after binding to EGFR. Furthermore, HB-EGF transduced intracellular downstream cAMP-PKA signaling to promote the phosphorylation of JNK and ERK whose blockage impeded the induction of HB-EGF on estrogen secretion. Meanwhile, HB-EGF enhanced the accumulation of intracellular Ca2+ whose chelation by BAPTA-AM abrogated the stimulation of HB-EGF on FOXO1 along with an obvious diminishment for estrogen production. cAMP-PKA-JNK/ERK-Ca2+ pathway played an important role in the crosstalk between HB-EGF and FOXO1. Treatment of GCs with HB-EGF resulted in mitochondrial dysfunction as evinced by the reduction of ATP content, mtDNA copy number and mitochondrial membrane potential. Additionally, HB-EGF facilitated the opening of mitochondrial permeability transition pore via targeting BAX and raised the release of cytochrome C from mitochondria into the cytosol to trigger the apoptosis of GCs, but this effectiveness was counteracted by estrogen receptor antagonist. Collectively, HB-EGF might induce mitochondrial dysfunction and GCs apoptosis through advancing estrogen hypersecretion dependent on cAMP-PKA-JNK/ERK-Ca2+-FOXO1 pathway and act as a promising therapeutic target for PCOS.  相似文献   
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