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1.
Worldwide, cervical cancer is the second most common cancer in women, after breast cancer. The prevalence of this malignant disease is estimated at 1.4 million cases worldwide, causing about 290,000 deaths and 500,000 new cases per year, of which 80% correspond to women living in developing countries. In this work we propose a family of ordered models for basal cells of the cervix corresponding to different stages ranging from normal cells to the formation of precancerous lesions. We analyse the first member of the family analytically and for the second member we developed a non-standard numerical method in order to extract some biological information. 相似文献
2.
Sung-Chou Li Kuo-Chung Lan Hsuan-Ning Hung Wan-Ting Huang Yun-Ju Lai Hsin-Hsin Cheng Chih-Chang Tsai Kun-Long Huang Huey-Ling You Te-Yao Hsu 《International journal of molecular sciences》2022,23(10)
Placenta accreta spectrum (PAS) accounts for 7% of maternal mortality and is associated with intraoperative and postoperative morbidity caused by massive blood loss, infection, and adjacent organ damage. The aims of this study were to identify the protein biomarkers of PAS and to further explore their pathogenetic roles in PAS. For this purpose, we collected five placentas from pregnant subjects with PAS complications and another five placentas from normal pregnancy (NP) cases. Then, we enriched protein samples by specifically isolating the trophoblast villous, deeply invading into the uterine muscle layer in the PAS patients. Next, fluorescence-based two-dimensional difference gel electrophoresis (2D-DIGE) and MALDI-TOF/MS were used to identify the proteins differentially abundant between PAS and NP placenta tissues. As a result, nineteen spots were determined as differentially abundant proteins, ten and nine of which were more abundant in PAS and NP placenta tissues, respectively. Then, specific validation with western blot assay and immunohisto/cytochemistry (IHC) assay confirmed that heat shock 70 kDa protein 4 (HSPA4) and chorionic somatomammotropin hormone (CSH) were PAS protein biomarkers. Further tube formation assays demonstrated that HSPA4 promoted the in vitro angiogenesis ability of vessel endothelial cells, which is consistent with the in vivo scenario of PAS complications. In this study, we not only identified PAS protein biomarkers but also connected the promoted angiogenesis with placenta invasion, investigating the pathogenetic mechanism of PAS. 相似文献
3.
四川盆地老气田二次开发优化技术及应用 总被引:1,自引:0,他引:1
经过近60年的开发,四川盆地的许多老气田已进入低压、低产的开发中后期,部分气田虽然已濒临废弃,但其中仍尚存较多剩余天然气资源未采出。通过梳理分析,认为具备二次开发条件的气田多存在地层水活跃形成水封难以解封、低渗透储量难动用等问题。为此,从老气田二次开发的定义出发,全面阐述了其技术路线及优选条件:(1)在建立缝洞系统多储渗体模式的基础上,采用压力重整曲线进行地质模型正演、生产动态反演特征曲线诊断,提出了复杂岩溶缝洞系统多储渗体识别及定量描述方法,结合U型管气水赋存新模式,形成了强水侵多缝洞系统天然气储量计算新技术;(2)建立孔、洞、缝三重介质数值模型,形成强水侵底水缝洞气藏"水平井排水+直井采气"排采井网模拟及效果评价新技术;(3)依托精细气藏描述形成的配套集成技术,重构气藏地质模型,分类评价气藏低渗透储量,结合井网优化、水平井地质导向、分段酸化压裂等工艺技术,进一步提高有效动用率;(4)建立多节点、多环节输气管网模型,形成区域性管网整体模拟优化及预测技术。实施效果表明,该二次开发技术在老气田产能建设、提高老气田采收率、延缓老气田产量递减、稳定老气田产量等方面均具有明显成效。 相似文献
4.
Jia Shi Riku Kanoya Yurina Tani Sodai Ishikawa Rino Maeda Sana Suzuki Fumiya Kawanami Naoko Miyagawa Katsuhiko Takahashi Teruaki Oku Ami Yamamoto Kaori Fukuzawa Motowo Nakajima Tatsuro Irimura Nobuaki Higashi 《International journal of molecular sciences》2022,23(9)
We examined whether sulfated hyaluronan exerts inhibitory effects on enzymatic and biological actions of heparanase, a sole endo-beta-glucuronidase implicated in cancer malignancy and inflammation. Degradation of heparan sulfate by human and mouse heparanase was inhibited by sulfated hyaluronan. In particular, high-sulfated hyaluronan modified with approximately 2.5 sulfate groups per disaccharide unit effectively inhibited the enzymatic activity at a lower concentration than heparin. Human and mouse heparanase bound to immobilized sulfated hyaluronan. Invasion of heparanase-positive colon-26 cells and 4T1 cells under 3D culture conditions was significantly suppressed in the presence of high-sulfated hyaluronan. Heparanase-induced release of CCL2 from colon-26 cells was suppressed in the presence of sulfated hyaluronan via blocking of cell surface binding and subsequent intracellular NF-κB-dependent signaling. The inhibitory effect of sulfated hyaluronan is likely due to competitive binding to the heparanase molecule, which antagonizes the heparanase-substrate interaction. Fragment molecular orbital calculation revealed a strong binding of sulfated hyaluronan tetrasaccharide to the heparanase molecule based on electrostatic interactions, particularly characterized by interactions of (−1)- and (−2)-positioned sulfated sugar residues with basic amino acid residues composing the heparin-binding domain-1 of heparanase. These results propose a relevance for sulfated hyaluronan in the blocking of heparanase-mediated enzymatic and cellular actions. 相似文献
5.
雁探1井是中国石油天然气股份有限公司青海油田分公司的一口重点矿权保护井,是青海油田柴达木盆地一里坪地区落雁山构造一口四开直井型风险井,完钻井深为5 909.95 m,钻探主要目的是探索落雁山构造E32~N1含油气性;了解落雁山地区古-新近系暗色泥岩发育情况以及生烃能力,为下步盆地腹部大型区带热成因气勘探研究及部署提供依据。该井地质条件复杂,没有任何实钻参考资料,存在高温、高密度、高压盐水层、高浓度CO2等叠加复杂因素,实际使用钻井液密度高达2.50 g/cm3,井底实测温度高达205℃,CO2侵高达100%,加之多层高压盐水存在,是一口典型的“四高”井,钻井施工难度极大。优选采用了BH-WEI钻井液体系,围绕高温稳定性、抗酸性气体污染、抗盐水污染、高密度流变性、滤失量与流变性矛盾等技术难点,精细调整钻井液配方及维护处理措施,较好地解决了一系列技术难题和矛盾,顺利钻至设计井深5 700 m,后加深钻进至5 909.95 m突遇设计外的异常高压盐水层,由于关井压井时间过长,事故完井。该井技术难点典型,积累了宝贵的现场施工经验,具有很好的借鉴指导意义。 相似文献
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储层泥浆侵入深度预测方法研究 总被引:4,自引:0,他引:4
泥浆侵入半径的确定尚缺乏严格的验证标准.以油水两相渗流理论和离子扩散方程为基础,结合储集层特点,研究了不同储层参数下泥浆滤液对地层的侵入特性.数值模拟侵入时间选取10 d和20 d.数值模拟结果表明,侵入半径在渗透率不变的情况下随孔隙度的增大而减小,在孔隙度不变的情况下随渗透率的增大而增大;当渗透率和孔隙度都发生变化时,泥浆侵入半径一般随孔隙度的增加呈幂函数增加.依据这种关系对测井资料约束处理,得到的泥浆侵入半径较客观地反映了地层的真实情况. 相似文献
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