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81.
Abstract

Since the emergence of patients with COVID-19 in December 2019, the virus has rapidly spread worldwide. Children with malignant tumors are more prone to be infected and develop severe infections. Prevention and control of the pandemic and ensuring the progress of the cancer diagnosis and treatment is a significant problem in the current scenario. This article proposes a scientific management system for patients with solid tumors to guarantee emergency surgery, rationally arrange limited-term surgery, appropriately defer elective surgery, and guarantee regular chemotherapy, while protecting children from SARS-CoV-2 infection and ensuring the continuity of comprehensive diagnosis and treatment.  相似文献   
82.
目的:探讨靛玉红衍生物PHⅡ-7抗乳腺癌耐药株MCF-7/ADR增殖作用的初步机制。方法:MTT法检测PHⅡ-7的体外杀伤活性;RT-PCR法、Western blot法检测基因、蛋白表达水平;构建干扰c-fos的短发夹RNA真核表达载体,转染MCF-7/ADR细胞,并建立稳定转染的细胞系;采用细胞计数法绘制生长曲线探讨c-fos表达下调对乳腺癌细胞增殖的影响。结果:PHⅡ-7剂量依赖性地抑制乳腺癌敏感株MCF-7及耐药株MCF-7/ADR增殖;c-fos在耐药株MCF-7/ADR表达明显高于敏感株MCF-7;PHⅡ-7明显抑制c-fos的表达;shRNA显著抑制了c-fos蛋白表达,细胞增殖也被显著抑制。结论:靛玉红衍生物PHⅡ-7浓度依赖性地抑制乳腺癌耐药株MCF-7/ADR增殖,其作用可能与抑制原癌基因c-fos有关。  相似文献   
83.
目的:探讨参芍降脂片对蛋黄乳剂腹腔注射致急性高脂血症模型小鼠的血脂水平及肝功能指标的影响。方法:采用75%蛋黄乳剂腹腔注射建立急性高脂血症模型,连续灌胃给予参芍降脂片11天,末次给药2h后,除正常对照组外其余各组腹腔注入新鲜蛋黄乳剂0.1ml/10g,20h后摘眼球取血,检测血清总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)含量。结果:参芍降脂片300mg/kg可降低小鼠血清TC、TG、LDL-C、ALT、AST,升高HDL-C/TC比值;参芍降脂片150mg/kg可显著升高小鼠血清HDL-C/TC;参芍降脂片75mg/kg可显著降低小鼠血清TC、TG、LDL-C、ALT、AST,升高HDL-C/TC比值。结论:参芍降脂片能改善蛋黄乳剂致急性高脂血症模型小鼠的血脂水平及肝功能。  相似文献   
84.
目的:建立痛风颗粒的质量标准。方法:采用薄层色谱法对方中牛蒡子、威灵仙等进行了鉴别;用高效液相色谱法测定方中牛蒡子苷的含量。结果:薄层鉴别专属性强;牛蒡子苷线性范围为0.96-4.8μg(r=0.9998),平均回收率为98.59%,RSD值为1.80%(n=6)。结论:所建立的方法操作简单,结果准确,灵敏度高,重现性好。该质量标准能有效地控制痛风颗粒的质量。  相似文献   
85.
基于代谢组学的系统化理论,以UPLC/QTOF分析系统为核心手段,结合生物样品分析制备方法,研究CCL_4诱导肝损伤大鼠的代谢组变化,以及茵陈蒿汤干预后的肝损伤大鼠代谢组的回调趋势。同时,借助MS解析理论和主成分分析软件,明晰表征大鼠肝损伤的5个内源性特征生物标记物,并结合系统生物学的理论还原肝损伤的机理与实质,以及茵陈蒿汤的肝损伤防治机理,从药物代谢组学角度对经典方剂防治肝损伤给出全新解释。  相似文献   
86.
中药及复方的体内代谢研究是当今探讨体内过程和阐明药效物质基础及作用机制的前沿热点领域,也为深层诠释中医药科学内涵、中医药理论的现代创新以及中药制药产业链的现代化提供了有效的途径。中药及其复方体内代谢研究有助于揭示药效物质基础、药效成分的体内动态规律,明晰体内药效成分与表观药效间的时量与时效间的关联,破译合“诸药之长”以成“有制之师”背后隐藏的配伍规律科学真谛,为打破长久以来困扰中医药“知其然,不知其所以然”的尴尬局面提供契机。对于建设符合中医药学科规律的ADME/Tox新药筛选平台,指导脱胎于中医经方又高于经方的创新型中药制剂的开发奠定了基础。本文对近年来中药及其复方的体内代谢研究现状和未来发展进行了综述和评价。  相似文献   
87.

Aim of the study

As a traditional Chinese medicine, seed of Platycladus orientalis(Linnaeus) Franco has been extensively used as a tonic and sedative remedy. The present study was conducted to investigate whether lifespan was extended and the mechanisms of n-butanol extract from seed of Platycladus orientalis (BSPO) in Caenorhabditis elegans. The findings could provide the pharmacological basis for a treatment in traditional medicine.

Materials and methods

Lifespan extension by BSPO was evaluated under normal culture conditions and in a stress test. A possible mechanism of the anti-aging effect of BSPO, a change in the stress-resistance of related proteins, was also investigated in C. elegans.

Results

It has been shown that BSPO could significantly extend lifespan of C. elegans in a concentration dependent manner under normal culture conditions and stress. Further studies demonstrated that BSPO treatment significantly decreased reactive oxygen species (ROS) accumulation, up-regulated resistance to stress of related proteins, including glutathione S-transferase-4 (GST-4) and heat shock protein-16.2 (HSP-16.2), and reduced the amount of lipofuscin in transgenic C. elegans.

Conclusion

These results indicated that BSPO extended the lifespan, which could be attributed to its direct ROS scavenging activity, reducing the amount of lipofuscin and increasing the expression of gens associated with resistance to stress. These obtained data provided valuable support for traditional clinical practice to extend lifespan and to provide tonic remedy.  相似文献   
88.
89.

Background

Accumulating evidence demonstrates that complex diseases may arise from cooperative effects of multiple dysfunctional miRNAs. Thus, identifying abnormal functions cooperatively regulated by multiple miRNAs is useful for understanding the pathogenesis of complex diseases.

Methods

In this study, we proposed a multistep method to identify dysfunctional miRNA-mRNA regulatory modules (dMiMRMs) in a specific disease, in which a group of miRNAs cooperatively regulate a group of target genes involved in a specific function. We identified dysfunctional miRNAs, which were differentially expressed and inversely regulated most of their target genes, by integrating paired miRNA and mRNA expression profiles and miRNA target information. Then, we identified cooperative functional units, in each of which a pair of miRNAs cooperatively repressed function-enriched and highly interconnected target genes. Finally, the cooperative functional units were assembled into dMiMRMs.

Results

We applied our method to glioblastoma (GBM) and identified GBM-associated dMiMRMs at the population, subtype, and individual levels. We identified 5 common dMiMRMs using all GBM samples, 3 of which were associated with the prognosis in patients with GBM and were better predictors of prognosis than were miRNAs or mRNAs alone. By applying our approach to GBM subtypes, we found consistent dMiMRMs across GBM subtypes, and some subtype-specific dMiMRMs were observed. Furthermore, personalized dMiMRMs were identified, suggesting significant individual differences in different patients with GBM.

Conclusions

Our method provides the capability to identify miRNA-mediated dysfunctional mechanisms underlying complex diseases.  相似文献   
90.
目的:探讨与中性粒细胞异常增殖相关的BCR/ABL-慢性白血病的临床特征.方法:报告3例不同类型与中性粒细胞异常增殖相关的BCR/ABL-慢性白血病并结合文献进行讨论.结果:3例均为老年男性,表现为以中性粒细胞为主的白细胞异常增多、BCR/ABL融合基因阴性.例1诊断为慢性中性粒细胞白血病(CNL),脾大,外周血以成熟中性粒细胞增高为特征,胞浆内中毒颗粒易见,无明显病态造血,中性粒细胞碱性磷酸酶(NAP)染色强阳性,骨髓粒系增生明显活跃.例2诊断为不典型慢性髓细胞白血病(aCML),血涂片示不成熟粒细胞比例增高伴粒系病态造血,尤其核染色质异常浓聚更为明显,骨髓象表现为髓系增生和病态造血,原始细胞轻度增多.例3诊断为慢性粒单核细胞白血病(CMML),外周血成熟单核细胞数量和比例异常偏高,粒系病态如核分叶过多、环状核和假性Pelger-Huet畸形等易见,骨髓髓系增生明显活跃伴病态造血,无原始细胞增多.结论:中性粒细胞异常增殖相关的BCR/ABL-慢性白血病较为少见,易于误诊,细胞形态学特征是诊断BCR/ABL-慢性白血病的基础.临床表现、多种实验室检查结果尤其是分子生物学等有助于正确诊断这类疾病.  相似文献   
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