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上颌骨改良Le FortⅠ型截骨术的三维建模和术后咬合有限元分析
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作者 刘楚晴 李阳 +1 位作者 毕绍洋 林阳阳 《中国医科大学学报》 北大核心 2024年第1期46-50,共5页
目的根据CT扫描数据,基于4种软件建立光顺的上颌骨三维几何模型,模拟改良Le FortⅠ型截骨术及固定方案,对患者术后咬合情况进行有限元分析。方法使用Mimics软件初步处理CT图像,建立STL模型。将模型导入Inspire Studio软件中,建立光滑的P... 目的根据CT扫描数据,基于4种软件建立光顺的上颌骨三维几何模型,模拟改良Le FortⅠ型截骨术及固定方案,对患者术后咬合情况进行有限元分析。方法使用Mimics软件初步处理CT图像,建立STL模型。将模型导入Inspire Studio软件中,建立光滑的PolyNURBS几何模型。使用SpaceClaim软件,模拟手术截骨及钛板、钛钉固定方案。使用ANSYS Workbench软件,对术后患者咬合情况进行三维有限元分析。结果仿真结果显示,在磨牙咬合状态下有限元模型的连接关系建立准确无误。在共计6 N的咬合力作用下,钛板最大等效应力为73 MPa。结论本研究采用的上颌骨建模和分析方法可获得适用于仿真分析的光滑几何模型,有限元分析结果可以为各类正颌手术的固定方案提供参考。 展开更多
关键词 上颌骨建模 有限元分析 改良le FortⅠ型截骨术 应力分布
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A novel herbal combination ameliorates ovarian dysfunction and regulates altered biochemical parameters in rats with letrozole-induced polycystic ovary syndrome
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作者 Sunita Shailajan Sasikumar Menon +1 位作者 Swati Singh Yugandhara Patil 《Asian pacific Journal of Reproduction》 2023年第1期23-34,共12页
Objective:To investigate the potential activity of novel herbal combination and novel herbal formulation(syrup)in female Sprague Dawley rats with letrozole-induced polycystic ovary syndrome(PCOS).Methods:Forty-two rat... Objective:To investigate the potential activity of novel herbal combination and novel herbal formulation(syrup)in female Sprague Dawley rats with letrozole-induced polycystic ovary syndrome(PCOS).Methods:Forty-two rats were randomly divided into seven groups with six rats in each group.Group 1 received 0.5%carboxy methylcellulose orally for 37 days and served as the normal control group.Group 2 was orally administered with letrozole of 1 mg/kg for 21 days and served as the PCOS induction group without treatment.Group 3 to 7 were administered with letrozole of 1 mg/kg for 21 days orally to induce PCOS,and then respectively received clomiphene citrate at 1 mg/kg,100 and 200 mg/kg of novel herbal combination,200 mg/kg of novel herbal formulation(syrup),and 400 mg/kg of marketed formulation of Pushyanuga churna,once daily for 15 days.Effects of the novel herbal combination and its syrup formulation were evaluated on the hormonal profile,the levels of antioxidants,the lipid profile and on the ovarian morphology,using letrozole-induced PCOS model in rats.Results:Letrozole caused alterations in hormonal levels and lipid levels similar to PCOS and ovarian histology showed presence of ovarian cysts confirming the induction of PCOS in rats.On treatment with the novel herbal combination and its syrup formulation in PCOS-induced rats,the altered hormonal and lipid profiles showed significant recovery to normal levels.Ovarian histology confirmed the restoration of folliculogenesis in the PCOS-induced rats.The treatment with the syrup formulation of novel herbal combination was found to be more effective than novel herbal combination and showed better recovery in various parameters evaluated.The results of the study,however,suggested that treatment with novel herbal combination and its syrup formulation provided minimal protection against oxidative stress caused due to the induction of PCOS.Conclusions:The integrated approach for management of PCOS is to counterbalance the limitations associated with modern therapy.Both the novel herbal combination and the syrup formulation of novel herbal combination show efficacy in the management of PCOS in rats and restore folliculogenesis in the ovary.The syrup formulation of novel herbal combination is most effective in the management of PCOS and shows potential to be developed as an adjuvant therapeutic agent. 展开更多
关键词 Polycystic ovarian syndrome Polyherbal combination letrozole Pushyanuga churna Clomiphene citrate HISTOPATHOLOGY Biochemical HERBAL
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亚临界区圆柱绕流相干结构壁面模化混合RANS/LES模型
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作者 季梦 尤云祥 +3 位作者 韩盼盼 邱小平 马乔 吴凯健 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第5期190-216,共27页
本文发展了一种具有壁面模化大涡模拟能力的雷诺平均纳维-斯托克斯(RANS)和大涡模拟(LES)方法的混合模型(简称WM-HRL模型),致力于对亚临界区雷诺数钝体绕流相干结构这类复杂流动现象进行高置信度的CFD解析模拟研究.该方法通过一个仅与... 本文发展了一种具有壁面模化大涡模拟能力的雷诺平均纳维-斯托克斯(RANS)和大涡模拟(LES)方法的混合模型(简称WM-HRL模型),致力于对亚临界区雷诺数钝体绕流相干结构这类复杂流动现象进行高置信度的CFD解析模拟研究.该方法通过一个仅与当地网格空间分布尺寸有关的湍动能解析度指标参数rk即可实现从RANS到LES的无缝快速转换,并且RANS/LES混合转换区的边界位置及其各个分区(包括RANS区、LES区及RANS/LES混合转换区)对湍动能的解析能力均可通过两个指标参数nrk1-Q和nrk2-Q准则进行预先设定.通过对雷诺数Re=3900下圆柱绕流场的系列数值模拟研究,获得了能够高置信度解析并捕捉其绕流场中三维时空瞬态发展相干结构特性的湍动能解析度指标参数nrk1-Q和nrk2-Q准则的组合条件.研究表明,该WM-HRL模型不仅能够准确获取圆柱绕流场中剪切层小尺度K-H不稳定性结构的精细谱结构,而且在同一套网格系统下通过变化湍动能解析度指标参数nrk2-Q和nrk1-Q准则的组合条件,还可以精细解析圆柱绕流场中两类不同回流区的长度结构特征,及其对应的圆柱尾部近壁面处V和U形两个平均流向速度剖面的分支结构特性. 展开更多
关键词 圆柱绕流 相干结构 KELVIN-HELMHOLTZ不稳定性 混合RANS/leS模型
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基于LES湍流模型的角形喷嘴数值模拟
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作者 邓富春 王尊策 +2 位作者 刘海水 李森 岳宇航 《煤矿机械》 2024年第7期203-206,共4页
针对RANS方法存在空化流场预测不准确的问题,通过采用大涡模拟(LES)对角形喷嘴进行数值模拟来获得其瞬时速度场以及空化云分布。通过对其流场进一步分析,揭示了空化水射流在发展过程中漩涡结构与空化之间的关系以及不同压力下的射流分... 针对RANS方法存在空化流场预测不准确的问题,通过采用大涡模拟(LES)对角形喷嘴进行数值模拟来获得其瞬时速度场以及空化云分布。通过对其流场进一步分析,揭示了空化水射流在发展过程中漩涡结构与空化之间的关系以及不同压力下的射流分布特征,为工程实践应用及空化射流机理提供了理论参考。 展开更多
关键词 空化水射流 漩涡 leS 流场分析
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基于WRF-LES模式的大气边界层近地风场精细化模拟研究
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作者 刘达琳 陶韬 +2 位作者 曹勇 周岱 韩兆龙 《上海交通大学学报》 EI CAS CSCD 北大核心 2024年第2期220-231,共12页
台风等极端气象灾害对工程结构安全造成严重威胁,研究近地面大气边界层精细化模拟对于土木工程具有重要应用价值.数值天气预报系统(WRF)中的大涡模拟(LES)模块具有参数方案多、精度高等优点,适用于近地面风场精细化模拟,但数值天气预报... 台风等极端气象灾害对工程结构安全造成严重威胁,研究近地面大气边界层精细化模拟对于土木工程具有重要应用价值.数值天气预报系统(WRF)中的大涡模拟(LES)模块具有参数方案多、精度高等优点,适用于近地面风场精细化模拟,但数值天气预报-大涡模拟(WRF-LES)精细化模拟效果与参数设置密切相关.寻求适用于精细化模拟近地面风场的参数设置,选用WRF-LES模式中的几种次网格模型和空间差分格式,采用较细密的网格分辨率,进行理想大气边界层模拟.对比平均风速剖面、湍流强度剖面和功率谱等风场特性,讨论关键参数对近地面风场模拟精度的影响,确定合适的参数设置.研究表明:对次网格模型,非线性回波散射和各向异性(NBA1)模型可有效改善近地面风场模拟精度;对网格方案,在计算域底部不均匀加密垂直网格可更好地描述近地面风场空间分布特征,有效减小计算资源;对空间差分格式,偶数阶差分相较奇数阶差分格式可捕获更小尺度湍流结构.所提出的WRF-LES模式参数方案,可为精细化模拟近地面风场和台风边界层提供技术参考. 展开更多
关键词 次网格模型 网格分辨率 空间差分格式 数值天气预报-大涡模拟
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来曲唑联合地塞米松对多囊卵巢综合征患者血清Galectin-3及HSP70的影响
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作者 朱莎 刘妮英 +1 位作者 梁爽爽 肖新益 《西部医学》 2024年第2期258-261,267,共5页
目的 探讨来曲唑联合地塞米松对多囊卵巢综合征(PCOS)患者血清半乳糖凝集素-3(Galectin-3)及热休克蛋白(HSP70)表达的影响。方法 选择2019年6月—2021年6月在我院治疗的PCOS患者220例为研究对象,按随机数表法分为对照组(n=110)和观察组(... 目的 探讨来曲唑联合地塞米松对多囊卵巢综合征(PCOS)患者血清半乳糖凝集素-3(Galectin-3)及热休克蛋白(HSP70)表达的影响。方法 选择2019年6月—2021年6月在我院治疗的PCOS患者220例为研究对象,按随机数表法分为对照组(n=110)和观察组(n=110),对照组常规给予来曲唑治疗。观察组在对照组的基础上加用地塞米松联合治疗。观察并比较两组患者的激素水平,促排卵情况,血清抗苗勒管激素(AMH)、Galectin-3、HSP70及单核细胞趋化蛋白-1(MCP-1)水平及不良反应发生率。结果 治疗后两组患者的性激素水平均改善,且观察组变化幅度高于对照组(P<0.05)。观察组患者雌二醇(E_(2))用量低于对照组,成熟卵泡数量和最大卵泡直径均高于对照组(均P<0.05)。两组患者的早期流产率差异无统计学意义(P>0.05);观察组患者的妊娠率高于对照组(P<0.05)。治疗前两组患者AMH、Galectin-3、HSP70、MCP-1水平差异无统计学意义(P>0.05),治疗后两组患者的AMH、Galectin-3、HSP70、MCP-1水平均降低,且观察组低于对照组(P<0.05)。观察组和对照组分别有35例和34例出现胃肠道反应、头痛、乳房胀痛等不良反应,两组差异无统计学意义(χ^(2)=0.021,P=0.885)。结论 来曲唑联合地塞米松可能减轻氧化应激反应,减轻胰岛素抵抗,调节激素水平,促进排卵,安全性高,值得推广应用。 展开更多
关键词 多囊卵巢综合征 来曲唑 地塞米松 热休克蛋白70 半乳糖凝集素-3 抗苗勒管激素 单核细胞趋化蛋白-1
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Preliminary study of letrozole use for improving spermatogenesis in non-obstructive azoospermia patients with normal serum FSH 被引量:8
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作者 Giorgio Cavallini Giovanni Beretta Giulio Biagiotti 《Asian Journal of Andrology》 SCIE CAS CSCD 2011年第6期895-897,共3页
We investigated whether letrozole (2.5 mg day-1) improves sperm count in non-obstructive azoospermia (NOA) patients. Four men were included in this study, and they had folliculo-stimulating hormone and other hormo... We investigated whether letrozole (2.5 mg day-1) improves sperm count in non-obstructive azoospermia (NOA) patients. Four men were included in this study, and they had folliculo-stimulating hormone and other hormone levels within the normal range and no varicoceles or chromosomal aberrations. These four patients were administered letrozole for 3 months. Sperm count, testicular volume, gonadotropin, testosterone (T) and estradiol (E2) blood levels were assessed before, during and 1 week after the suspension of treatment. All patients showed spermatozoa in their ejaculate, increased gonadotropin and T levels and lower E2 levels (P〈0.05 in all cases), when letrozole was administered. This suggests that letrozole treatment might improve sperm count in an NOA sub-population; however, more studies, including the proper controls, are needed to confirm its efficacy. 展开更多
关键词 letrozole medical treatment non-obstructive azoospermia SPERMATOGENESIS
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基于RANS和LES的高大空间建筑气流组织仿真和热舒适度评价方法
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作者 张慎 程明 +4 位作者 王义凡 孟凡凯 李霆 陈菡 戢志峰 《系统仿真学报》 CAS CSCD 北大核心 2023年第10期2212-2222,共11页
针对大空间建筑的暖通空调设计,开展气流组织分析和热舒适评价对于改善室内环境热舒适度和降低能耗具有重要意义。结合基于雷诺时均方程的稳态分析和基于大涡模拟的瞬态分析这2种计算流体力学分析方法的特点,建立了高大空间建筑气流组... 针对大空间建筑的暖通空调设计,开展气流组织分析和热舒适评价对于改善室内环境热舒适度和降低能耗具有重要意义。结合基于雷诺时均方程的稳态分析和基于大涡模拟的瞬态分析这2种计算流体力学分析方法的特点,建立了高大空间建筑气流组织仿真方案和热舒适度评价方法。利用稳态分析计算消耗较小的特点,开展多工况热舒适度和空气质量评价;选取典型工况实施计算消耗较大的瞬态分析,获取空气调节全过程,给出室内温度达到设定温度所需要的空调运行时间,从而优化空调运行策略,降低能耗。基于实验结果对2种方法的准确性进行了验证,介绍了所用方法在实际工程项目中的应用,供其他工程参考。 展开更多
关键词 雷诺时均方程 大涡模拟 高大空间建筑 气流组织 热舒适度评价
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Stability-indicating liquid chromatographic method for the determination of Letrozole in pharmaceutical formulations 被引量:2
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作者 M.Mathrusri Annapurna Chitaranjan Mohapatro A.Narendra 《Journal of Pharmaceutical Analysis》 SCIE CAS 2012年第4期298-305,共8页
A stability-indicating high-performance liquid chromatographic method was developed and validated for the determination of Letrozole in tablet dosage forms. Reversed-phase chromatography was performed on Shimadzu Mode... A stability-indicating high-performance liquid chromatographic method was developed and validated for the determination of Letrozole in tablet dosage forms. Reversed-phase chromatography was performed on Shimadzu Model LC-Class-Vp with Lichrocart/Lichrosphere 100 C-18 (250 mm 4.6 mm, 5 mm particle size) column with methanol: tetra butyl ammonium hydrogen sulfate (80:20V/V) as mobile phase at a flow rate of 1 mL/min with UV detection at 240 nm. Linearity was observed in the concentration range of 0.5-150 mg/mL (R 2 0.9998) with regression equation y 102582xt43185. The limit of quantitation (LOQ) and limit of detection (LOD) were found to be 0.043 and 0.012 mg/mL respectively. The forced degradation studies were performed by using HCl, NaOH, H 2 O 2 , thermal and UV radiation. Letrozole is more sensitive towards alkaline conditions and very much resistant towards acidic, oxidative and photolytic degradations. The method was validated as per ICH guidelines. The RSD for intra-day (0.78-0.97) and inter-day (0.86-0.96) precision were found to be lesser than 1%. The percentage recovery was in good agreement with the labeled amount in the pharmaceutical formulations and the method is simple, specific, precise and accurate for the determination of Letrozole in pharmaceutical formulations. 展开更多
关键词 letrozole Liquid chromatography STABILITY-INDICATING
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Randomized controlled trial of Letrozole versus Clomiphene citrate for induction of ovulation in polycystic ovarian syndrome (PCOS): A Malaysian experience 被引量:3
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作者 Nik Hazlina Nik Hussain Munawwirah Ismail +3 位作者 Murizah Mohd. Zain Pu Chan Yeu Roszaman Ramli Wan Mohd Zahiruddin Wan Mohammad 《Open Journal of Obstetrics and Gynecology》 2013年第5期11-17,共7页
Background: The purpose of this study was to compare the effectiveness of Letrozole versus Clomiphene citrate for ovulation induction in polycystic ovarian syndrome (PCOS) with infertility. Methods: This was a prospec... Background: The purpose of this study was to compare the effectiveness of Letrozole versus Clomiphene citrate for ovulation induction in polycystic ovarian syndrome (PCOS) with infertility. Methods: This was a prospective randomized trial involving 150 women with PCOS attending the Infertility Clinic at three hospitals in Malaysia. During the initial visit, anthropometric measurements and baseline investigations were performed. Patients were randomized to 5.0 mg Letrozole daily (75 patients) or 100 mg Clomiphene citrate daily (75 patients) from the fifth until the ninth day of menstruation. Serial transvaginal scans were performed to see the dominant follicles, endometrial thickness and number of follicles. Transvaginal scans were performed serially to look for evidence of ovulation. Results: The subjects were homogenously distributed. The difference between Letrozole and Clomiphene citrate for ovulation rate was 59 (78.7%) versus 40 (53.3%). Patients taking Letrozole exhibited a mean endometrial thickness (ET) at mid cycle of menses (Day 11-D14) of9.2 mm(SD ± 2.3) versus8.4 mm(SD ± 2.2) for patients taking Clomiphene citrate, and these differences were statistically significant 展开更多
关键词 POLYCYSTIC Ovarian Syndrome OVULATION INDUCTION CLOMIPHENE CITRATE letrozole
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Crystal Engineering of Co(Ⅱ) Metal-organic Frameworks Based on the Hydrolysis Product of Letrozole and Coligands 被引量:1
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作者 康海霞 傅玉琴 +3 位作者 鞠丰阳 王玉芳 李晓玲 刘广臻 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第8期1266-1274,共9页
The cyanide groups of letrozole(1-[bis(4-cyanophenyl)methyl]-1,2,4-triazole) were hydrolyzed into the carboxylic groups under alkaline conditions. Then the hydrolysis product(1-[bis(4-carboxylphenyl)methyl]-1,2,4-tria... The cyanide groups of letrozole(1-[bis(4-cyanophenyl)methyl]-1,2,4-triazole) were hydrolyzed into the carboxylic groups under alkaline conditions. Then the hydrolysis product(1-[bis(4-carboxylphenyl)methyl]-1,2,4-triazole, H2ltzda) reacted with Co(NO3)2·6H2O in the presence of different bipyridl-typed ligands under hydrothermal conditions. As a result, two new Co(Ⅱ) MOFs were obtained, formulated as [Co2(ltzda)2(bpp)2]n(1) and {[Co2(ltzda)2(bpy)]·4H2O}n(2)(bpp = 1,3-di(4-pyridyl)propane, bpy = 4,4’-bipyridine). Two MOFs have been characterized by single-crystal X-ray diffraction, thermogravimetric analysis and magnetic measure. 1 displays a 2D metal-organic framework containing wave layers and 2 shows a pillared-layer structure existing in a 2-fold interpenetrated mode. 展开更多
关键词 letrozole Co(Ⅱ) METAL-ORGANIC frameworks HYDROLYSIS magnetic PROPERTY coligand
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Simultaneous Letrozole and Clomiphene Citrate versus Letrozole Alone in Clomiphene Citrate Resistant Polycystic Ovary Syndrome: A Randomised Controlled Trial 被引量:1
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作者 Mohamed A. Ibrahem 《Open Journal of Obstetrics and Gynecology》 2019年第11期1532-1540,共9页
Background: Polycystic ovary syndrome (PCOS) is a common cause of anovulatory infertility. The therapeutic strategies for clomiphene citrate (CC)- resistant patients include the addition of corticosteroids, extended d... Background: Polycystic ovary syndrome (PCOS) is a common cause of anovulatory infertility. The therapeutic strategies for clomiphene citrate (CC)- resistant patients include the addition of corticosteroids, extended duration of clomiphene, gonadotrophin therapy, laparoscopic ovarian drilling, in vitro fertilization or the use of aromatase inhibitors recently. Letrozole decreases estrogen levels in the body, so it releases the hypothalamus and/or pituitary gland from the negative feedback of estrogen. This increases levels of gonadotrophins, which stimulates follicular growth. Objectives: To evaluate the role of letrozole alone and simultaneous use of letrozole and clomiphene citrate (CC) for ovulation induction in patients with clomiphene citrate-resistant PCOS (CCR-PCOS). Patients and Methods: This open-label randomised controlled study was conducted in the Department of Obstetrics and Gynecology, Faculty of Medicine, Zagazig University, Egypt during the period from February 2018 to June 2019. The study included 60 CCR-PCOS patients who were randomly allocated by independent personnel into two arms: group A (letrozole alone) or B (letrozole + CC). In either group, monitoring the mean follicular diameter and endometrial thickness in the days 10, 12, and 14 of the cycle by transvaginal ultrasound and Measurement of serum Progesterone (ng/ml) 7 days after the expected time of ovulation. Results: We investigated various clinical and sonographic factors that may predict the outcome of the method of induction of ovulation in CCR-PCOS with no significant affection for the results. There was a non-significant difference between the studied groups regarding ovulation and pregnancy per cycle or per patient. Conclusion: Letrozole alone or simultaneous use of letrozole and CC offers a good second-line option for induction of ovulation in CCR-PCOS patients. However, the combination of CC and letrozole did not add any benefit over the use of letrozole alone regards ovulation rate, follicular volume, endometrial thickness, pregnancy rate and live birth rate. 展开更多
关键词 OVULATION Induction letrozole CLOMIPHENE CITRATE POLYCYSTIC OVARY Syndrome
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Short-term Femara (letrozole) treatment and suppression of Ki67 expression in postmenopausal endometrial carcinoma 被引量:1
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作者 Lloyd H. Smith Gary Leiserowitz +1 位作者 Guibo Xing John Bishop 《Open Journal of Obstetrics and Gynecology》 2013年第3期347-351,共5页
Objective: To determine if short-term treatment with Femara (letrozole) induces measurable reduction in tumor Ki67 expression in postmenopausal women with FIGO grade 1 and 2 endometrial carcinoma. Methods: In this non... Objective: To determine if short-term treatment with Femara (letrozole) induces measurable reduction in tumor Ki67 expression in postmenopausal women with FIGO grade 1 and 2 endometrial carcinoma. Methods: In this non-randomized prospective study, 12 patients were given Femara (letrozole) 2.5 mg daily for approximately 3 weeks prior to planned hysterectomy for FIGO grade 1 or 2 endometrial carcinoma. A group of 12 demographically similar patients were enrolled as no-treatment controls. Ki67 expression in tumor cells was quantitated by immunohistochemistry with mechanical scanning within the initial endometrial biopsy and compared to that in the hysterectomy specimen for each patient in the treatment and control groups. Results: The treatment and control groups were similar in age, tumor grade and FIGO stage. When “aromatase inhibitor responsiveness” was defined as proportionate decline in Ki67% stained tumor cells of at least 70% between the pre-treatment endometrial biopsy and post-treatment hysterectomy specimens, 5 of 12 patients were found to be “responsive” in the treatment group with none of the controls fulfilling these criteria. Conclusion: Femara (letrozole) 2.5 mg daily for approximately 3 weeks induced a significant reduction in tumor cell Ki67 expression among 5 of 12 (41%) postmenopausal women with FIGO grade 1 or 2 endometrial carcinoma. We postulate that Ki67 may be a useful marker during aromatase inhibitor medical treatment of patients with endometrial cancer who are not candidates for surgical treatment. 展开更多
关键词 ENDOMETRIAL Carcinoma AROMATASE Inhibitor letrozole KI67
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SPE-UPLC-MS/MS assay for determination of letrozole in human plasma and its application to bioequivalence study in healthy postmenopausal Indian women 被引量:1
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作者 Pravin G.Vanol Puran Singhal +3 位作者 Priyanka A.Shah Jaivik V.Shah Pranav S.Shrivastav Mallika Sanyal 《Journal of Pharmaceutical Analysis》 SCIE CAS 2016年第4期276-281,共6页
A rapid and sensitive ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) method is described for determination of letrozole in human plasma.Following solid phase extraction(SPE) of letroz... A rapid and sensitive ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) method is described for determination of letrozole in human plasma.Following solid phase extraction(SPE) of letrozole and letrozole-d4 on Orochem DVB-LP cartridges,chromatography was performed on Acquity UPLC BEH C_(18)(50 mm × 2.1 mm.1.7 μm) column using methanol-0.1%formic acid in water(85:15,v/v) as the mobile phase.Detection was carried out on a triple quadrupole mass spectrometer with an electrospray source,operated under positive ionization mode.Quantitation of letrozole and letrozole-d4 was done using multiple reaction monitoring(MRM) following the transitions at m/z286.2→217.0 and m/z 290.2→221.0,respectively.The calibration plots were linear through the concentration range of 0.10-100 ng/mL(r^2 ≥ 0.9990) using 100 μL human plasma.The extraction recovery of letrozole ranged from 94.3%to 96.2%and the intra-batch and inter-batch precision was ≤ 5.2%.The method was successfully applied to a bioequivalence study of letrozole after oral administration of2.5 mg tablet formulation to 16 healthy postmenopausal Indian women.The assay reproducibility was also established through incurred sample reanalysis(ISR) of 74 subject samples. 展开更多
关键词 letrozole letrozole-D4 UPLC-MS/MS Solid phase extraction Bioequivalence study
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上颌Le FortⅠ前徙术与前份根尖下截骨后退术术后软组织变化的比较研究
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作者 李沛然 毕瑞野 +5 位作者 王旻 王瑞宇 刘尧 姜楠 曹品银 祝颂松 《国际口腔医学杂志》 CAS CSCD 2023年第3期293-301,共9页
目的测量不同上颌骨正颌术式前后鼻唇区域软组织变化,分析可能导致变化的因素。方法2017—2021年于四川大学华西口腔医院正颌及关节外科住院行正颌手术的患者37例,其中因上颌后缩行上颌骨Le FortⅠ型骨切开前徙术(LFIA)的患者18例,因上... 目的测量不同上颌骨正颌术式前后鼻唇区域软组织变化,分析可能导致变化的因素。方法2017—2021年于四川大学华西口腔医院正颌及关节外科住院行正颌手术的患者37例,其中因上颌后缩行上颌骨Le FortⅠ型骨切开前徙术(LFIA)的患者18例,因上颌前突行上颌骨前份根尖下截骨后退术(AMOS)的患者19例。收集其术前即刻和术后6~12个月的螺旋CT影像,通过Mimics和3-Matic软件进行三维重建和匹配,测量软硬组织标志点变化。使用GraphPad Prism软件进行统计学分析,显著性水平α=0.05。结果2种术式术后最主要的软组织变化均发生在上唇区域且改变方向与骨组织移动方向相同。在前后向软组织改变上,LFIA组软硬组织改变的比例为0.628,而AMOS组为0.465。颊部和鼻尖软组织在2种术式后均发生了前移,其中AMDS组中颊部软组织前移的量与软组织厚度的改变具有显著正相关性。在垂直向软组织变化上,LFIA组鼻尖点发生上抬且其距离与颌骨前徙距离具有显著正相关性,AMOS组上唇缘点发生下降且其距离与颌骨后退距离具有显著正相关性。在水平向软组织变化上,鼻翼宽度在行2种术式后均出现增宽,但在AMOS组中鼻翼宽度增宽量与后退距离呈显著负相关。结论AMOS和LFIA术后的鼻唇区域软组织改变与颌骨移动量及方向具有显著相关性。上唇前后向改变与颌骨移动距离具有显著正相关性,鼻翼宽度改变与上颌骨后退距离具有相关性。以上相关性的发现可能帮助临床医生更准确地判断鼻唇区域的软硬组织改变。 展开更多
关键词 软组织 牙颌面畸形 上颌骨le FortⅠ型骨切开术 上颌骨前份骨切开术 正颌外科
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上颌Le Fort Ⅰ型截骨术对鼻形态影响的研究进展
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作者 叶亨妮 陈学鹏 +2 位作者 唐贶昀 周梦琪 胡济安 《口腔医学》 CAS 2023年第11期1041-1046,共6页
上颌Le Fort Ⅰ型截骨术是正颌外科中矫治上颌骨畸形最常采用术式之一。但是,上颌骨的移动、肌肉的剥离会影响周围软组织的形态,其中鼻形态的改变越来越受到重视。已有研究报道,正颌手术后鼻形态的不利改变是降低患者手术满意度的主要... 上颌Le Fort Ⅰ型截骨术是正颌外科中矫治上颌骨畸形最常采用术式之一。但是,上颌骨的移动、肌肉的剥离会影响周围软组织的形态,其中鼻形态的改变越来越受到重视。已有研究报道,正颌手术后鼻形态的不利改变是降低患者手术满意度的主要原因之一。明确上颌Le Fort Ⅰ型截骨术对鼻形态的影响能够帮助医生更准确地预测术后鼻形态的变化,从而优化手术设计、提高医患沟通效率。本文将对上颌Le Fort Ⅰ型截骨术后鼻部形态变化的研究进展作一综述,旨在为临床实践提供相应的参考。 展开更多
关键词 le FortⅠ型截骨术 三维扫描仪 鼻形态 鼻翼基底缝合
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上颌骨Le Fort Ⅰ型截骨术后上颌窦炎的研究现状
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作者 王守鹏 孟箭 张雷 《中国口腔颌面外科杂志》 CAS 2023年第1期75-80,共6页
上颌窦炎是Le Fort Ⅰ型截骨术后常见的并发症,对正颌术后的骨质愈合等非常不利。明确Le Fort Ⅰ型截骨术后上颌窦炎发生的相关因素,针对性采取预防措施,早期发现与及时治疗,对于降低上颌窦炎的发生率,加快患者术后康复,以及提升患者术... 上颌窦炎是Le Fort Ⅰ型截骨术后常见的并发症,对正颌术后的骨质愈合等非常不利。明确Le Fort Ⅰ型截骨术后上颌窦炎发生的相关因素,针对性采取预防措施,早期发现与及时治疗,对于降低上颌窦炎的发生率,加快患者术后康复,以及提升患者术后生活质量具有重要意义。本文就上颌骨Le Fort Ⅰ型截骨术后并发上颌窦炎的影响、病因、诊断、治疗和预防等进行总结,为正颌外科相关医护人员早期诊治上颌窦炎提供参考。 展开更多
关键词 le FortⅠ型截骨术 上颌窦炎 术后并发症 正颌手术
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基于WRF-LES的崇礼复杂地形局地风场模拟研究 被引量:1
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作者 张珊 王宗敏 +1 位作者 黄刚 薛学武 《高原气象》 CSCD 北大核心 2023年第1期197-209,共13页
采用四重嵌套的WRF-LES,针对2022年北京冬奥会张家口崇礼赛区开展局地风场模拟试验,基于地面自动气象站和激光雷达观测资料,对一次晴空高压系统控制下的具有明显局地风环流特征的天气个例模拟结果进行检验评估。文中引入了STRM130 m地... 采用四重嵌套的WRF-LES,针对2022年北京冬奥会张家口崇礼赛区开展局地风场模拟试验,基于地面自动气象站和激光雷达观测资料,对一次晴空高压系统控制下的具有明显局地风环流特征的天气个例模拟结果进行检验评估。文中引入了STRM130 m地形数据、glc201527 m土地利用数据和CL‐DAS的土壤湿度数据用以提高模拟结果的准确性,并设计了敏感性试验来探讨不同资料对模拟结果的影响。结果表明:(1)WRF-LES能够呈现出复杂地形下局地风场的时空变化特征,各站风向绝对误差在10°~60°,风速绝对误差在0.5~2 m·s^(-1)。在山谷和山沟区域,模拟风场和观测风场都表现出明显的日变化特征,海拔较高站点的误差比海拔相对较低站点的误差更小。海拔较低站点在山谷风或上下坡风发展稳定时段风向误差较小,风向转换时段误差较大。(2)更新地形、土地利用以及CLDAS土壤湿度初始场对模拟结果都有一定程度改善。其中更新CLDAS土壤湿度初始场对风向和2 m气温的改善效果最为明显,风向绝对误差减小4.26°,2 m气温绝对误差减小0.84℃。更新土地利用对风速的改善效果最明显,风速绝对误差减小0.32 m·s^(-1)。(3)CLDAS土壤湿度较ERA5的土壤湿度明显偏小,较小的土壤湿度会使土壤具有低传导率或低热容量,这种状态会导致地表温度在白天的升温幅度和夜间的降温幅度都增大,较强的白天增温垂直高度可延伸至700~900 m,较强的夜间降温垂直高度在200 m以下,与此同时,较小土壤湿度也会使白天低层风速增大,这些特征在山谷和山沟中更为明显。 展开更多
关键词 WRF-leS 复杂地形 风场模拟 CLDAS土壤湿度
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Letrozole versus Gonadotropin in Unexplained Infertile Couples Failed to Conceive with Clomiphene Citrate
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作者 Moustafa Abbas Ibrahaiem Sherin A. Shazly +2 位作者 Khaled F. Helal Hala Mowafy Manal M. El Behery 《Open Journal of Obstetrics and Gynecology》 2014年第10期636-641,共6页
Background:?Unexplained infertility represents about 15% - 20% of infertile couples. Usually, these cases need assistance. Clomiphene citrate is the most used drug for this problem but sometimes pregnancy failed to ac... Background:?Unexplained infertility represents about 15% - 20% of infertile couples. Usually, these cases need assistance. Clomiphene citrate is the most used drug for this problem but sometimes pregnancy failed to achieve it, so other options for assistance are gonadotrophin or letrezole. The objective of our study was to compare the pregnancy rate for letrezole and gonadotropin inunexplained infertile women’s who failed to conceive with clomiphene citrate. Methods: This prospective quasi-randomized trial was carried out in cytogenetic unite at obstetrics and gynecology department, Zagazig University Hospital. 140 infertile females were included, induction of ovulation by letrozole for half of them and by gonadotrophin for the other half. Results: There was statistically highly significant decrease in duration of stimulation, E2 levels and endometrial thickness at day of HCG in letrezole group, no significant difference between two groups as regard number of follicles and pregnancy rate per cycle, while the cumulative pregnancy rate and the cost of stimulation are significantly higher in gonadotrophin group. Conclusion: In patient with unexplained infertility who failed to conceive with clomiphene citrate, gonadotrophins have a higher pregnancy rate than letrezole. However, pregnancy rate was high enough with lower cost with letrezole to be acceptable and justified its use in this group of patients. 展开更多
关键词 letrozole GONADOTROPIN Infertility CLOMIPHENE CITRATE
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改良鼻旁植骨减少Le FortⅠ型截骨术后上颌骨垂直向复发的探讨
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作者 葛卫文 祁磊 +1 位作者 王昀 张雷 《中国口腔颌面外科杂志》 CAS 2023年第2期163-167,共5页
目的:探讨改良鼻旁植骨是否能减少Le Fort 1型截骨下降手术术后上颌骨垂直向的复发。方法:选择双颌手术中上颌骨下降幅度>3 mm的患者30例,分为改良鼻旁植骨组和非改良鼻旁植骨组。利用术前(T0)、术后3天(T1)和术后6个月(T2)的颌面CT... 目的:探讨改良鼻旁植骨是否能减少Le Fort 1型截骨下降手术术后上颌骨垂直向的复发。方法:选择双颌手术中上颌骨下降幅度>3 mm的患者30例,分为改良鼻旁植骨组和非改良鼻旁植骨组。利用术前(T0)、术后3天(T1)和术后6个月(T2)的颌面CT数据对上颌骨位置进行三维测量;同时利用T1与T2的CT数据计算植骨块厚度的变化。采用SPSS 22.0软件包对数据进行统计学分析。结果:术后6个月,在垂直方向上,改良鼻旁植骨组上切牙点复发量为(0.54±0.35)mm,非改良鼻旁植骨组上切牙点复发量为(1.18±0.76)mm(P=0.3997)。2组在前后、水平方向的复发率无显著差异。改良鼻旁植骨组的植骨块厚度降低(11.75±6.25)%,非改良鼻旁植骨组的植骨块厚度降低(33.77±11.56)%(P<0.0001)。结果:改良鼻旁植骨可有效减少植骨块吸收,以及术后上颌骨垂直向复发。 展开更多
关键词 鼻旁植骨 复发 三维分析 le FortⅠ型截骨术 正颌手术
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