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目的:本实验建立一种有效的河豚毒素毒性检测细胞模型,为河豚毒素解毒药物高通量筛选奠定基础。方法:
用不同浓度膜电位荧光探针DiBAC4(3)在全黑底透96 孔细胞培养板中孵育SH-SY5Y 人神经母细胞瘤细胞,利用
不同浓度藜芦定使细胞去极化,利用荧光酶标仪测定不同浓度河豚毒素对细胞膜电位的影响。结果:以DiBAC(4 3)
1000 nmol/L、藜芦定200 μmol/L、河豚毒性100 μmol/L 作用于SH-SY5Y 细胞,观察到河豚毒素使该细胞膜电位
变化最显著。结论:通过测量毒素诱导的膜电位变化可以初步预测和量化河豚毒素的毒性,可用于筛选解毒剂。
该方法操作简便,并且可以实现高通量自动化筛选。 相似文献
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《Taiwanese journal of obstetrics & gynecology》2022,61(1):135-137
ObjectiveWe present the application of quantitative fluorescent polymerase chain reaction (QF-PCR) for the rapid confirmation of trisomy 13 of maternal origin in a pregnancy with fetal holoprosencephaly (HPE), cyclopia, polydactyly, omphalocele and cell culture failure.Case reportA 21-year-old, gravida 2, para 0, woman was referred for termination of the pregnancy at 17 weeks of gestation because of the abnormal ultrasound finding of alobar HPE. The pregnancy was subsequently terminated, and a 118-g malformed male fetus was delivered with cyclopia, bilateral postaxial polydactyly of the hands and ruptured omphalocele. Postmortem cell culture of the placental tissue and umbilical cord was not successful. The parental karyotypes were normal. QF-PCR analysis using the polymorphic DNA markers of D13S1810, D13S790 and D13S251 on the DNA extracted from placenta, umbilical cord and parental bloods showed trisomy 13 of maternal origin.ConclusionPerinatal diagnosis of concomitant HPE, polydactyly and omphalocele should raise a suspicion of fetal trisomy 13. QF-PCR analysis is useful for rapid confirmation of trisomy 13 and the parental origin especially under the circumstance of cell culture failure, and the information acquired is very useful for genetic counseling of the parents. 相似文献
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目的 比较不同子宫内膜准备方案对冻融胚胎移植( frozen-thawed embryo transfer, FET)患者临床妊娠率及活产率等临床结局的影响及其相关因素分析.方法 回顾性分析2016年7月1日—2018年12月31日在同济大学附属同济医院生殖医学中心进行的605个FET周期患者的临床资料及胚胎实验室数据.依据子宫内膜处理方案分为自然周期(natural cycle, NC)组、激素替代周期( hormone replacement cycle, HRT)组、促性腺激素释放激素激动剂联合激素替代周期( gonadotropin releasing hormone agonist plus hormone replacement cycle, GnRHa+HRT)组,比较3组周期患者的基本资料、子宫内膜厚度、子宫内膜容积、子宫动脉搏动指数( pulsatility index, PI)、阻力指数(resiteance index, RI)、收缩期与舒张期血流速度比值( peak systolic velocity/end-diastolic velocity, S/D)与妊娠结局的相关性.结果 3组患者年龄、不孕年限、体质量指数、冻胚级别差异无统计学意义(P>0. 05);3种内膜准备方案的内膜转化日子宫内膜厚度、子宫内膜容积差异有统计学意义(P<0. 05),而子宫动脉PI、RI、S/D值均无明显差异;3组患者的早产率、早期自然流产率、晚期流产率、异位妊娠率、双胎妊娠率等妊娠结局,差异均无统计学意义(P>0. 05),而3组间足月产率的差异有统计学意义( P<0. 05);多因素Logistic回归分析表明,不同子宫内膜准备方案、单/双胎妊娠及不孕类型为患者足月产的独立影响因素,其中NC方案、单胎妊娠及原发不孕患者的足月产可能性更大(P<0. 05).结论 NC周期行FET可获得较高的足月产率;经阴道超声测定子宫内膜容积及子宫动脉血流动力学参数可以反映子宫内膜容受性,可以指导FET胚胎移植时机的选择.对于薄型子宫内膜患者,给予HRT方案或GnRHa+HRT方案准备内膜,可获得更多移植机会. 相似文献
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Ricardo Cruz Luís Correia Aloys Dushimimana Susana Cabral-Fonseca Jos Sena-Cruz 《Materials》2021,14(6)
This work addresses the durability of structural epoxy adhesives and carbon fibre reinforced polymer (CFRP) laminates typically used in strengthening of existing reinforced concrete structures exposed to natural ageing. The experimental program included four natural (real) outdoor environments inducing ageing mainly caused by carbonation, freeze-thaw attack, elevated temperatures, and airborne chlorides from seawater. Moreover, a control (reference) environment (20 °C of temperature and 55% of relative humidity) and an environment involving water immersion of the materials under controlled temperature (20 °C of temperature) were also included in this investigation. The characterization involved the assessment of the physical, chemical and mechanical properties along a study period of up to two years. Furthermore, comparisons between the natural ageing tests developed in the scope of the present work and accelerated ageing tests existing in the literature were performed. Regarding to the epoxy adhesives, an increase in the glass transition temperature with the time was observed, while the tensile properties decreased, regardless of the outdoor environment. The CFRP laminates were marginally affected by the studied environments. Despite the remarkable dispersion of the results observed in the accelerated ageing tests for the period investigated, this testing protocol yielded higher mechanical degradation than under natural ageing. 相似文献
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Objective: To study the effect and mechanism of Huayu Wan (化瘀丸, HYW) in combination of chemotherapy of tumor treatment. Methods: HYW serum was added in Lewis cells to assess its impact on fluorescent doxorubicin delivery in vitro. Then, Lewis tumor cells was implanted in C57BL/6 mice via xenograft transplantation. Tumor growth was measured and signal intensity corresponding to blood flow was assessed by laser doppler perfusion imaging (LDPI). Finally, the effect of HYW on the efficacy of doxorubicin was studied. Results: HYW can improve the transfer of fluorescent doxorubicin into cells. The blood flow signal in the tumor tissues of the HYW group was higher than that of the control group (P<0.01). Furthermore, HYW improved drug delivery of doxorubicin to tumor tissues, and this activity was associated with HYW-induced microvascular proliferation (P<0.01). Conclusions: HYW can promote microangiogenesis and increase blood supply in tumor tissues, which in turn may increase the risk of metastasis. At the same time, HYW increases drug delivery and improves the efficacy of chemotherapy drugs through vascular proliferation. Therefore, rational judgment must be exercised when considering applying HYW to an antitumor regimen. 相似文献
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目的:分析疏肝健脾方对2型糖尿病合并抑郁症肝郁脾虚证患者神经内分泌指标、血清簇集蛋白、水通道蛋白-4(AQP4)、NOD样受体热蛋白结构域相关蛋白-3(NLRP3)炎性小体、内源性分泌型糖基化终产物受体(esRAGE)水平的影响。方法:纳入84例2型糖尿病合并抑郁症肝郁脾虚证患者,随机分为对照组与治疗组各42例。对照组患者采用二甲双胍联合帕罗西汀治疗,治疗组患者在此基础上联用疏肝健脾方治疗。连续治疗3个月后,对两组患者治疗前后各项生化指标进行对比分析。结果:治疗后,治疗组患者空腹血糖(FBG)、餐后2 h血糖(2 h PBG)、糖化血红蛋白(HbAlc)、HAMD评分、促肾上腺皮质激素(ACTH)、皮质醇(COR)水平均明显低于对照组(P<0.05);两组患者促甲状腺激素(TSH)、游离型甲状腺素(FT4)、游离型三碘甲状腺原氨酸(FT3)水平比较,差异均无统计学意义(P>0.05);治疗组患者簇集蛋白、AQP4、白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)、白细胞介素-18(IL-18)、单个核细胞(PBMCs)中NLRP3mRNA、ASC mRNA、Caspase-1 mRNA表达水平均明显低于对照组(P<0.05),esRAGE水平明显高于对照组(P<0.05)。结论:疏肝健脾方可以调节2型糖尿病合并抑郁症肝郁脾虚证患者神经内分泌功能,提高机体血糖控制水平,改善患者抑郁情绪状态,其机制可能与下调NLRP3炎性小体mRNA表达、上调esRAGE水平有关。 相似文献