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Detection of Progesterone Receptor as a Method of Diagnosing Mammary Cancer in Female Dogs
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作者 José de Jesús Vázquez Pérez Angel Ramses Figueroa Hernandez +2 位作者 Jorge Peregrina Sandoval Guillermo Nolasco Rodríguez Manuel Rosales Cortés 《Open Journal of Veterinary Medicine》 CAS 2024年第8期217-227,共11页
Introduction: Canine mammary gland tumor is the most common type of neoplasia in non-ovariectomized bitches. Approximately 50% of tumors are malignant. Neoplasms originating from the mammary gland represent the most c... Introduction: Canine mammary gland tumor is the most common type of neoplasia in non-ovariectomized bitches. Approximately 50% of tumors are malignant. Neoplasms originating from the mammary gland represent the most common neoplastic disease in canines in Veterinary Medicine. Aim: Relate the expression of the receptor to progesterone (PR) with the tumor stage of canine mammary carcinoma. Material and Methods: Analytical-cross-sectional study, samples of paraffinized tumor tissue obtained from 30 canine patients with breast cancer were used. The expression of PR was performed by immunohistochemical labeling, using murine anti-PR (anti-PR Biocare brand). A descriptive analysis was carried out with the results using the SPSS program. Results: The predominant histological subtype of breast cancer was tubular carcinoma with 12 patients, followed by papillary cystic carcinoma with 6 patients, solid carcinoma 5, carcinosarcoma 4 and comedocarcinoma 3. There was a significant trend between breast cancer subtypes, histological grade G1. Among the histopathological findings, the degree of invasion is related to the presence of tumor cells in adjacent lymph nodes, which is why it is a prognostic indicator. The expression of PR in the tumor tissue samples it was 42.8% positive versus 57.14% negative, of which 75% correspond to G1, 8.3% to G2 and 16.6% to G3. With respect to the relationship of the expression of PR vs type of tumor, it was found that 50% correspond to tubular carcinoma, 33.3% to papillary cystic carcinoma, 8.3% to solid carcinoma and 8.3% to comedocarcinoma. Conclusion: The hormone receptor was negative in more than half of the patients and histological grade is significantly associated with tumor subtypes, this study emphasizes the need to introduce receptor testing into our routine clinical practice to offer the best treatment for breast cancer. 展开更多
关键词 CANCER Mammary Gland progesterone IMMUNOHISTOCHEMISTRY progesterone Membrane Receptor Component 1 (PGRMC 1)
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Diagnostic efficacy of virtual organ computer-assisted analysis in measuring the volume ratio of subchorionic hematoma with serum progesterone
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作者 Lin-Ling Shen Jing Shi +2 位作者 Chang-Wei Ding Gao-Le Dai Qi Ma 《World Journal of Clinical Cases》 SCIE 2024年第17期3053-3060,共8页
BACKGROUND Subchorionic hematoma(SCH)is a common complication in early pregnancy characterized by the accumulation of blood between the uterine wall and the chorionic membrane.SCH can lead to adverse pregnancy outcome... BACKGROUND Subchorionic hematoma(SCH)is a common complication in early pregnancy characterized by the accumulation of blood between the uterine wall and the chorionic membrane.SCH can lead to adverse pregnancy outcomes such as miscarriage,preterm birth,and other complications.Early detection and accurate assessment of SCH are crucial for appropriate management and improved pregnancy outcomes.AIM To evaluate the diagnostic efficacy of virtual organ computer-assisted analysis(VOCAL)in measuring the volume ratio of SCH to gestational sac(GS)combined with serum progesterone on early pregnancy outcomes in patients with SCH.METHODS A total of 153 patients with SCH in their first-trimester pregnancies between 6 and 11 wk were enrolled.All patients were followed up until a gestational age of 20 wk.The parameters of transvaginal two-dimensional ultrasound,including the circumference of SCH(Cs),surface area of SCH(Ss),circumference of GS(Cg),and surface area of GS(Sg),and the parameters of VOCAL with transvaginal three-dimensional ultrasound,including the three-dimensional volume of SCH(3DVs)and GS(3DVg),were recorded.The size of the SCH and its ratio to the GS size(Cs/Cg,Ss/Sg,3DVs/3DVg)were recorded and compared.RESULTS Compared with those in the normal pregnancy group,the adverse pregnancy group had higher Cs/Cg,Ss/Sg,and 3DVs/3DVg ratios(P<0.05).When 3DVs/3DVg was 0.220,the highest predictive performance predicted adverse pregnancy outcomes,resulting in an AUC of 0.767,and the sensitivity,specificity were 70.2%,75%respectively.VOCAL measuring 3DVs/3DVg combined with serum progesterone gave a diagnostic AUC of 0.824 for early pregnancy outcome in SCH patients,with a high sensitivity of 82.1%and a specificity of 72.1%,which showed a significant difference between AUC.CONCLUSION VOCAL-measured 3DVs/3DVg effectively quantifies the severity of SCH,while combined serum progesterone better predicts adverse pregnancy outcomes. 展开更多
关键词 Subchorionic hematoma Virtual organ computer-assisted analysis Gestational sac Serum progesterone Ultrasound parameters Adverse pregnancy outcomes
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Vaginal Progesterone (VP) versus VP plus Intermittent Intramuscular Progesterone (IMP) Use in Frozen/Thawed Blastocyst Transfer Cycles: An Observational Cohort Study
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作者 Serdar Celik Dilek Cengiz Celik 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第2期192-206,共15页
Objective: Comparison of vaginal progesterone (VP) versus VP and intermittent intramuscular progesterone (IMP) use in frozen/thawed blastocyst transfer cycles. Study Design: A single center retrospective analyses of 4... Objective: Comparison of vaginal progesterone (VP) versus VP and intermittent intramuscular progesterone (IMP) use in frozen/thawed blastocyst transfer cycles. Study Design: A single center retrospective analyses of 470 elective FET cycles which were performed between January 2015 and September 2019 were evaluated. Patients were divided into two groups. Control group was consisted of VP (n = 272), the study group was consisted of VP plus IMP (n = 198) users. Results: The number of transfer attempts in control and study groups was 272 and 198, respectively. Age (29.8 ± 4 vs 30.6 ± 4;p = 0.09), BMI (22 ± 2 vs 21.9 ± 3;p = 0.79) and the number of transferred embryos (1.4 ± 0.5 vs 1.4 ± 0.5;p = 0.48) were comparable between groups. Altough, implantation rates (43.7% vs 43.6%;p = 0.9), ectopic pregnancy (0.8% vs 0.3%;p = 0.46) and abortion rates (8.2% vs 4.8%;p = 0.07) were similar. Biochemical pregnancy rate (8.4% vs 3.4% p = 0.01) in control group and ongoing pregnancy rate (OPR) (27.9% vs 38.1%;p = 0.005) in study group were significantly higher. Conclusion: Within the FET cycles in which good quality blastocyst are being transferred additional IMP supplementation to VP may increase OPR while reducing the biochemical pregnancy rate. 展开更多
关键词 Vaginal progesterone Supplementation progesterone Supplementation IVF Cryopreserved Embryo Transfer Hormone Replacement Therapy
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基于CEEMDAN-QPSO-BLS模型的径流预测研究 被引量:2
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作者 刘扬 赵丽 《中国农村水利水电》 北大核心 2024年第1期101-108,共8页
准确的径流预测是水资源优化配置和高效利用的前提,是制定防洪减灾决策的基础,然而受到人类活动、环境、气候等因素的影响,径流序列呈现出非线性、非稳态、多尺度变化的特点,这为径流的精准预测增加了难度。为提高径流预测的精准度和可... 准确的径流预测是水资源优化配置和高效利用的前提,是制定防洪减灾决策的基础,然而受到人类活动、环境、气候等因素的影响,径流序列呈现出非线性、非稳态、多尺度变化的特点,这为径流的精准预测增加了难度。为提高径流预测的精准度和可信度,结合自适应噪声完备集合经验模态分解(Complete Ensemble Empirical Mode Decomposition with Adaptive Noise,CEEMDAN)方法,量子粒子群优化算法(Quantum Particle Swarm Optimization,QPSO)、宽度学习系统(Broad Learning System,BLS)模型,提出了一种基于CEEMDAN-QPSO-BLS组合式的径流预测模型。该组合模型首先使用CEEMDAN方法对原始径流信号进行分解,得到若干相对平稳的本征模态分量。其次利用QPSO算法对BLS模型的特征层节点组数、增强层节点组数和组内节点数进行寻优,得到最优的宽度学习网络拓扑结构,进而使用最优的QPSOBLS对多个稳态分量进行预测,并对预测分量进行重构,从而获得更高的预测精度。以黄河流域小浪底水库的日径流值为实验数据,将EMD-QPSO-BLS、QPSO-BLS作为CEEMDAN-QPSO-BLS的对比模型,并采用纳什效率系数(NSE)、均方根误差(RMSE)、平均绝对误差(MAE)和平均绝对百分比误差(MAPE)作为模型预测可信度和精准度的评价指标。实验表明,在预见期4天内,与QPSO-BLS、EMD-QPSO-BLS模型相比,CEEMDAN-QPSO-BLS的预测精准度分别提高了79.87%、19.80%,可信度分别提高了131.2%、10.98%,径流预测精度的提高,可为防洪抗旱保护人民生命财产和可持续发展提供决策支持。 展开更多
关键词 径流预测 宽度学习 量子粒子群 CEEMDAN EMD
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C57BL/6小鼠微小三毛滴虫的观察与种系发育分析
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作者 温福利 《福建畜牧兽医》 2024年第4期10-12,18,共4页
为鉴定从某外单位引进的C57BL/6小鼠粪样检测中发现的虫体种类,本试验对虫体进行形态学观察,并进行种系发育分析。取C57BL/6小鼠粪样涂片和瑞士染色后进行显微镜观察,提取粪样总DNA,根据三毛滴虫的16S rRNA进行PCR扩增后测序,运用MEGA1... 为鉴定从某外单位引进的C57BL/6小鼠粪样检测中发现的虫体种类,本试验对虫体进行形态学观察,并进行种系发育分析。取C57BL/6小鼠粪样涂片和瑞士染色后进行显微镜观察,提取粪样总DNA,根据三毛滴虫的16S rRNA进行PCR扩增后测序,运用MEGA11进行种系发育分析。显微镜观察发现,虫体符合微小三毛滴虫的形态学特征,测序发现微小三毛滴虫的基因序列与鼠三毛滴虫高度同源。 展开更多
关键词 C57bl/6小鼠 微小三毛滴虫 16S rRNA 种系发育分析
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Variation in Progesterone Levels and Urinary Tract Infections in Pregnant Women Attending Moi Teaching and Referral Hospital, Eldoret, Kenya 被引量:1
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作者 Anne Wanjiku Lizzy Mwamburi +1 位作者 Moses Ngeiywa Andrew Obala 《Open Journal of Medical Microbiology》 CAS 2023年第1期125-135,共11页
Background and Aims: Urinary tract infections (UTIs) are common among pregnant women and major predisposing factors for pyelonephritis linked to obstetrical complications including preterm labour and low infants’ bir... Background and Aims: Urinary tract infections (UTIs) are common among pregnant women and major predisposing factors for pyelonephritis linked to obstetrical complications including preterm labour and low infants’ birth weights. This study sought to determine the relationship(s) between pregnancy trimesters, UTIs and changes in progesterone levels among pregnant women. Materials and Methods: The study was conducted in 2016 at Moi Teaching and Referral Hospital (MTRH) antenatal clinic which is a referral facility that attends to patients from most Counties in western region of Kenya. A cross-sectional study design was used to collect blood and urine specimens from 78 participants. Blood was used to determine progesterone levels using ELISA technique and urine cultures with bacterial colony counts ≥ 10<sup>5</sup> were appropriately identified to species level. Trimester periods and participants’ demographic information were obtained using a structured questionnaire. Results: Culture results showed that the most abundant bacterial species isolated in urine from the pregnant women was Escherechia coli (63.7%). The more affected age-group was women between 30 - 39 years during trimester three, suggesting that bacterial colonization of genital track occurred more frequently in older compared to the younger women. There was an exponential increase in progesterone levels among the pregnant women during trimester three compared to other trimesters, although these increases occurred independent of age. However, high levels of progesterone among pregnant women in third trimester corresponded with increased number of E. coli causing UTI. Conclusion: The results showed that progesterone levels increase with trimester and the most prevalent bacteria associated with this was E. coli even though age and increase in progesterone levels had no significant impact on E. coli infection. 展开更多
关键词 Urinary Tract Infection progesterone Trimester Escherichia coli
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枸杞多糖对C57BL/6J骨质疏松症小鼠的早期防治
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作者 刘艺洁 赵薇 +9 位作者 李林隆 李海林 姚建花 李智东 刘飞 丁玉梅 孟海伟 于洋 王银 苗珍花 《宁夏医科大学学报》 2024年第6期586-591,共6页
目的探讨枸杞多糖(LBP)对C57BL/6J骨质疏松症小鼠的早期防治作用。方法选用12周C57BL/6J雌鼠,采用双侧卵巢完全切除术制备骨质疏松症模型,假手术组切除卵巢周围脂肪组织,术后1周,选取手术成功的小鼠分为假手术组、模型组和LBP组。LBP组... 目的探讨枸杞多糖(LBP)对C57BL/6J骨质疏松症小鼠的早期防治作用。方法选用12周C57BL/6J雌鼠,采用双侧卵巢完全切除术制备骨质疏松症模型,假手术组切除卵巢周围脂肪组织,术后1周,选取手术成功的小鼠分为假手术组、模型组和LBP组。LBP组给予灌胃LBP 0.1 g·kg^(-1),1次/d,连续12周,假手术组和模型组灌胃等量蒸馏水。酶联免疫吸附(ELISA)法检测小鼠血清中雌二醇(E_(2))含量;生物化学方法检测血清氧化应激指标丙二醛(MDA)、超氧化物歧化酶(SOD)含量;Micro CT扫描胫骨微观结构,观察骨小梁厚度(Tb·Th)、骨表面积和骨体积之比(BS/BV)、骨小梁分离度(Tb·Sp)、骨密度(BMD)、骨体积分数(BV/TV)、骨体积(BV)的变化。结果与假手术组小鼠比较,模型组小鼠的体质量增长率升高、子宫脏器系数明显减小、血清E_(2)含量下降、血清氧化应激指标MDA含量增高、SOD活力降低(P均<0.01);与模型组小鼠比较,LBP组小鼠子宫脏器系数、血清E_(2)含量差异均无统计学意义(P均>0.05),但体质量增长率下降、血清MDA含量降低、SOD活力增加(P均<0.01),骨组织BMD、BV升高(P均<0.05),Tb·Th及BV/TV均显著升高(P均<0.01)。胫骨三维重建图显示,模型组骨皮质变薄,呈现骨质疏松改变,骨小梁数量减少,排列紊乱,髓腔明显扩大;LBP组较模型组骨小梁数量增加。结论LBP可能通过调控早期骨质疏松症小鼠的氧化应激反应,发挥改善骨质疏松的作用。 展开更多
关键词 枸杞多糖 C57bl/6J小鼠 骨质疏松症 氧化应激 骨密度
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C57BL/6N小鼠早期视网膜变性及小胶质细胞活化状态研究
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作者 孟欢 邓婷婷 +4 位作者 刘自强 侯小玉 马传政 苑维 金明 《国际眼科杂志》 CAS 2024年第10期1536-1541,共6页
目的:观察C57BL/6N(Crb1 rd8/rd8)小鼠早期视网膜变性以及小胶质细胞的活化情况。方法:取雄性SPF级C57BL/6N小鼠15只、C57BL/6J小鼠15只,正常饲养。分别在入组时,入组4、8、12 wk,使用Micron-Ⅲ小动物视网膜影像系统进行双眼彩色眼底照... 目的:观察C57BL/6N(Crb1 rd8/rd8)小鼠早期视网膜变性以及小胶质细胞的活化情况。方法:取雄性SPF级C57BL/6N小鼠15只、C57BL/6J小鼠15只,正常饲养。分别在入组时,入组4、8、12 wk,使用Micron-Ⅲ小动物视网膜影像系统进行双眼彩色眼底照相检查计算病变数量、病变面积。观察结束后处死小鼠,摘取右侧眼球制备视网膜组织切片,进行HE染色后光镜下观察视网膜组织形态;采用免疫组织化学染色分析两组小鼠视网膜CX3CR1的表达水平及位置。摘取左侧眼球分离视网膜,使用Western-Blot检测CD86、CD206的表达情况,使用电化学发光法测定视网膜中IL-1β、IL-6、TNF-α、IL-4、IL-10炎性因子含量水平。结果:眼底彩照结果显示在入组4、8、12 wk,C57BL/6N组眼底病变数量均较入组时显著增加,与C57BL/6J组同时间点变化量比较均有差异(均P<0.05);眼底病变面积变化量两组间入组12 wk有差异(P<0.05),各组内变化量比较均无差异(均P>0.05);视网膜组织HE染色示:C57BL/6N组视网膜结构异常,细胞排列疏松、紊乱,光感受器层向视网膜内侧明显的玻璃膜疣样凸起,C57BL/6J组视网膜结构清晰,细胞排列有序,无明显异常;免疫组化结果示:C57BL/6N组视网膜中CX3CR1高表达于神经节细胞层、内外丛状层、感光细胞层及病灶处位置,平均光密度为0.285±0.056,C57BL/6J组为0.189±0.084(P<0.05);Western-Blot结果显示:与C57BL/6J组相比,C57BL/6N组视网膜CD86、CD206蛋白有不同程度升高,两组CD86蛋白表达有差异(P<0.05);细胞因子检测结果显示:C57BL/6N组IL-1β、TNF-α水平显著高于C57BL/6J组,而IL-10含量则明显较低(均P<0.05)。结论:C57BL/6N(Crb1 rd8/rd8)小鼠视网膜变性进展缓慢,随年龄呈进行性加重,病灶部位视网膜结构紊乱,伴有以M1型极化为主的小胶质细胞浸润。 展开更多
关键词 C57bl/6N 视网膜变性 年龄相关性黄斑变性 小胶质细胞 极化
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Establishment and Optimization of HPLC-MS/MS for Detection of Progesterone Residue in Raw Milk 被引量:1
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作者 Zhen ZHANG Jun ZHANG +3 位作者 Lei YAN Yuxi ZHAO Aifeng ZHANG Yuefei YAN 《Agricultural Biotechnology》 CAS 2019年第1期80-82,85,共4页
In order to establish an HPLC-MS/MS method for detecting progesterone in raw milk,raw milk was extracted with methanol,and then determined by HPLC-MS/MS after the purification with a C18 solid phase extraction column.... In order to establish an HPLC-MS/MS method for detecting progesterone in raw milk,raw milk was extracted with methanol,and then determined by HPLC-MS/MS after the purification with a C18 solid phase extraction column. Qualitative determination was performed according to retention time and selective ion abundance ratio,and quantification was performed by external standard method. The results showed that progesterone had a good linear relation in the range of0. 1-5. 0 ng/ml,with a correlation coefficient of 0. 999 9. The detection limit of the established method was 0. 02 μg/kg,and the quantification limit was0. 04 μg/kg. In the standard addition range of 0. 1-5. 0 ng/ml,the recovery ranged from 79. 6% to 105. 1%,with relative standard deviation≤8. 9%. Compared with the industry standard,the detection limit and the quantification limit of the established method are significantly reduced,and the sensitivity of the method is enhanced,so this method is suitable for the detection of progesterone residue in fresh milk in pastures. 展开更多
关键词 HPLC-MS/MS FRESH and raw MILK progesterone Method ESTAblISHMENT Optimization
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U2BL调控拟南芥下胚轴伸长的机制研究
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作者 张婉露 丁勇 《植物科学学报》 CAS CSCD 北大核心 2024年第1期66-74,共9页
下胚轴的伸长在植物早期存活和后期生长发育过程中均具有重要作用。本研究对拟南芥(Arabidopsis thaliana(L.)Heynh.)突变体进行了筛选,得到了具有短下胚轴表型的突变体u2bl,并对其下胚轴变短机制进行了初步研究。结果显示,突变体u2bl... 下胚轴的伸长在植物早期存活和后期生长发育过程中均具有重要作用。本研究对拟南芥(Arabidopsis thaliana(L.)Heynh.)突变体进行了筛选,得到了具有短下胚轴表型的突变体u2bl,并对其下胚轴变短机制进行了初步研究。结果显示,突变体u2bl在不同光照条件下均表现出下胚轴较短的表型。细胞学实验表明,突变体u2bl下胚轴细胞长度的降低是其下胚轴较短的原因。赤霉素(GAs)是促进下胚轴伸长的主效应因子。但u2bl突变体对外源GA处理及内源GA合成抑制剂多效唑(PAC)处理均不敏感,表明U2BL基因可能影响GA的信号转导。亚细胞定位结果表明,U2BL在细胞核中富集。荧光定量Q-PCR分析结果显示,在u2bl突变体中,PRE1、SAUR16、YUC2、YUC8和PIF4等基因的表达均有显著下调,U2BL可能通过调控上述基因来间接调控下胚轴的伸长。本研究结果为进一步探讨U2BL在拟南芥生长发育及在其他物种中可能行使的功能提供了参考。 展开更多
关键词 U2bl基因 拟南芥 下胚轴 赤霉素
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C57BL/6小鼠炎症性肠病模型的建立与指标评价
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作者 何家宇 杨茗淇 +4 位作者 伍娇 杨宇 姚欢 易金娥 孔丽 《中国畜牧兽医》 CAS CSCD 北大核心 2024年第9期4153-4163,共11页
【目的】通过葡聚糖硫酸钠(dextran sulfate sodium,DSS)或脂多糖(lipopolysaccharide,LPS)刺激构建小鼠炎症性肠病(inflammatory bowel disease,IBD)模型,为IBD研究提供高效经济的模型参考,并为IBD抗炎药物筛选与药效评价提供可靠的方... 【目的】通过葡聚糖硫酸钠(dextran sulfate sodium,DSS)或脂多糖(lipopolysaccharide,LPS)刺激构建小鼠炎症性肠病(inflammatory bowel disease,IBD)模型,为IBD研究提供高效经济的模型参考,并为IBD抗炎药物筛选与药效评价提供可靠的方法支撑。【方法】本试验以C57BL/6雄性小鼠为研究对象,分别暴露于不同浓度的DSS(3%、4%和5%)7 d或LPS(5、10和20 mg/kg)4 h。通过测量小鼠结肠长度,HE染色观察肠道形态结构及实时荧光定量PCR检测肠道炎性因子的mRNA表达等对模型进行评价。【结果】DSS诱导小鼠结肠变短、病理出血、腺体萎缩、结构排列絮乱、炎性细胞浸润以及结肠中炎性因子白细胞介素-1β(interleukin-1β,IL-1β)、IL-6、IL-10和肿瘤坏死因子-α(tumour necrosis factor-α,TNF-α)的mRNA表达显著上升(P<0.05),4%DSS即可高效建立IBD模型。同时,LPS引起小鼠肠系膜出血、肠道肿胀和充血,肠绒毛高度降低,隐窝深度升高,小肠中IL-10和IL-1βmRNA水平升高、IL-6 mRNA水平下降,十二指肠和回肠TNF-αmRNA水平上升,空肠TNF-αmRNA水平降低,且以5 mg/kg LPS综合影响最为显著。【结论】4%DSS和5 mg/kg LPS是C57BL/6小鼠IBD模型建立的最适浓度,肠道病理形态改变、肠道炎性细胞浸润及炎性因子IL-1β、IL-6、IL-10和TNF-α的mRNA表达异常是评价IBD模型的重要指标。 展开更多
关键词 葡聚糖硫酸钠(DSS) 脂多糖(LPS) 炎症性肠病 肠道炎症 C57bl/6小鼠
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BL Lac的光学多普勒因子估算
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作者 黄家伟 潘树蓉 +3 位作者 吴健 叶旭鸿 曹健鸿 樊军辉 《天文学报》 CAS CSCD 北大核心 2024年第5期70-77,共8页
蝎虎天体(BL Lacertae object,BL Lac)是一类特殊的活动星系核,表现出极端的观测特征,如高光度和偏振、快速光变、超光速运动、射电核主导、极高能辐射等,极端观测特性可能都与喷流效应有关,而表征喷流效应的物理量是多普勒因子(Doppler... 蝎虎天体(BL Lacertae object,BL Lac)是一类特殊的活动星系核,表现出极端的观测特征,如高光度和偏振、快速光变、超光速运动、射电核主导、极高能辐射等,极端观测特性可能都与喷流效应有关,而表征喷流效应的物理量是多普勒因子(Doppler factor).多普勒因子有助于了解BL Lac的辐射物理和本征特性.基于BL Lac和Fanaroff-Riley typeⅠ/Fanaroff-Riley typeⅡ(G)的统一模型思路,提出BL Lac的本征视星等与红移(哈勃图)的分布应该与FRⅠ/FRⅡ(G)的观测视星等与红移的分布相似,并提出了估算BL Lac的光学多普勒因子的方法.该方法所估算的多普勒因子与前人的光学多普勒因子比较具有很好的相关性,说明该光学波段估算BL Lac多普勒因子的方法是可靠的. 展开更多
关键词 蝎虎天体:普通 星系:活动 星系:距离和红移 星系:喷流
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一种可快速验证的可聚合BLS签名方案
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作者 潘天雨 赵运磊 《密码学报(中英文)》 CSCD 北大核心 2024年第4期799-806,共8页
BLS签名是一种双线性映射友好椭圆曲线上的数字签名方案,它具有签名大小短、在聚合签名场景中验证高效、支持同态性与非交互聚合等优点.但由于需要进行双线性映射操作,单个BLS签名的验证算法相对较慢,这阻碍了其在区块链系统中进一步的... BLS签名是一种双线性映射友好椭圆曲线上的数字签名方案,它具有签名大小短、在聚合签名场景中验证高效、支持同态性与非交互聚合等优点.但由于需要进行双线性映射操作,单个BLS签名的验证算法相对较慢,这阻碍了其在区块链系统中进一步的应用.本文提出了一种BLS签名方案的变体—CPABLS,其主要优点如下:第一,将Chaum-Pedersen离散对数相等性证明纳入签名中,使得签名验证算法不再需要双线性映射操作,从而提升了验证速度;第二,在公钥聚合时只需对各个签名者的公钥简单求和,而无需进行大量的标量乘法操作;第三,相比于群G2,签名验证算法可在群G1中更快地进行哈希到曲线和聚合公钥检验操作.给出了该方案在聚合签名安全模型中的安全证明及原型实现,并进行了性能测试与效率评估. 展开更多
关键词 blS聚合签名 Chaum-Pedersen证明 高效验证
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基于RBF-BLS面向电动汽车低碳安全出行的SOH估计方法
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作者 李春喜 乔涵哲 +3 位作者 姚刚 姜淏予 崔向科 葛泉波 《上海交通大学学报》 EI CAS CSCD 北大核心 2024年第9期1454-1464,共11页
电动汽车充电过程的安全性与动力电池组的健康状态(SOH)紧密相关,因此SOH的高性能实时估计是充电过程中安全检测的重要基础.由于动力电池组的SOH受复杂结构、电芯类型、驾驶习惯、环境温度和充电行为等因素的深度影响,现有基于单个或少... 电动汽车充电过程的安全性与动力电池组的健康状态(SOH)紧密相关,因此SOH的高性能实时估计是充电过程中安全检测的重要基础.由于动力电池组的SOH受复杂结构、电芯类型、驾驶习惯、环境温度和充电行为等因素的深度影响,现有基于单个或少量特定电池电芯实验数据的方法研究在面对整车动力电池组实时SOH估计时遭遇模型复杂、数据缺失、实时性差、精度不足等难题.针对建模困难、实时性和精度不足等问题,应用多方法集成融合思想,在电池经验退化模型上引入径向基函数(RBF)优化的宽度学习(BLS)神经网络,提出一种高性能的动力电池组SOH估计方法.首先,该方法采用经验退化模型和离线历史充电数据得到初步的SOH值;其次,应用RBF神经网络给出一种BLS系统中初始权重矩阵的确定方法,建立经验退化与径向基函数优化的宽度学习神经网络(RBF-BLS);再次,采用RBF-BLS神经网络和实时充电数据训练得到估计误差,并对经验退化模型得到的SOH进行补偿,从而得到更高精度的SOH估计值;最后,采用基于充电运营企业实际充电数据的计算机仿真实例来验证新方法的有效性和优越性. 展开更多
关键词 充电安全 健康状态 经验退化模型 宽度学习
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孕期低剂量镉暴露对C57BL/6母鼠肾脏组织的毒性损伤作用
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作者 刘建军 许鹏 《农业技术与装备》 2024年第7期109-111,114,共4页
为研究孕期低剂量镉暴露对母鼠肾脏的毒性效应,基于前期构建的孕期低剂量镉暴露小鼠模型,通过组织显微切片技术对镉暴露母鼠的肾脏组织结构进行观察,并通过实时定量PCR法和蛋白质免疫印迹法对肾脏中炎症相关基因和凋亡调控基因的mRNA和... 为研究孕期低剂量镉暴露对母鼠肾脏的毒性效应,基于前期构建的孕期低剂量镉暴露小鼠模型,通过组织显微切片技术对镉暴露母鼠的肾脏组织结构进行观察,并通过实时定量PCR法和蛋白质免疫印迹法对肾脏中炎症相关基因和凋亡调控基因的mRNA和蛋白质表达水平进行检测。实验结果显示:孕期低剂量镉暴露可导致肾脏结构出现一定程度的病变,如肾小球内细胞数目增多,肾小囊变窄,肾小球略微肿胀等;与对照组相比,镉暴露母鼠肾脏中凋亡功能调控基因Bax的mRNA和蛋白质表达水平显著升高。综上所述,孕期低剂量镉暴露可导致母体肾脏结构发生损伤,该毒性作用可能与凋亡调控基因Bax的表达水平升高相关。研究结果旨在阐明孕期低剂量镉暴露对母体器官的毒性效应机制,为镉暴露下家畜的母胎健康风险评估和环境管理提供基础数据支持。 展开更多
关键词 孕期暴露 肾脏 C57bl/6小鼠
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What Prevents Eligible Patients from Receiving Progesterone Therapy to Prevent Recurrent Preterm Birth
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作者 Amanda Meyer Nancy Cipparrone +1 位作者 Andrea Buras Barbara V. Parilla 《Open Journal of Obstetrics and Gynecology》 2014年第7期395-398,共4页
Objective: The use of intramuscular 17-alpha-hydroxyprogesterone caproate (17-OHPC) has been shown to be beneficial for the prevention of preterm birth (PTB) in women with a prior history. Not all patients with a prio... Objective: The use of intramuscular 17-alpha-hydroxyprogesterone caproate (17-OHPC) has been shown to be beneficial for the prevention of preterm birth (PTB) in women with a prior history. Not all patients with a prior preterm birth receive 17-OHPC. The purpose of this study was to investigate potential barriers to receiving this therapy. Methods: A retrospective chart review of those patients at our institution who received the diagnosis of “previous preterm delivery” in 2010 and 2011 was performed to see whether they were offered and received 17-OHPC. Patients were considered eligible if they had a prior delivery at less than 36 weeks of gestation secondary to idiopathic preterm labor. For those patients that were deemed eligible but did not receive therapy, an explanation was sought. Results: Sixty-six charts were reviewed in detail. Forty-three patients were considered eligible to receive 17-OHPC. The remaining had medical indications for delivery including premature rupture of membranes (PROM) (15), intrauterine growth restriction (IUGR) (1), and hypertension (2). Of the 43 patients deemed eligible, 17 did not receive 17-OHPC. Of these, eight patients were not offered therapy, 2 patients declined therapy, 3 patients presented with therapy after 28 weeks (too late), and 4 received a prophylactic cerclage as their only therapy. There were no significant differences between the two groups. Conclusion: In an effort to increase 17-OHPC use among eligible patients, we must continually identify physician biases and patient barriers that prevent utilization of this intervention. In addition, patients who deliver preterm should be told the importance of presenting early in subsequent pregnancies in order to receive the full benefits of this therapy. 展开更多
关键词 progesterone PRETERM BIRTH PRETERM Delivery 17-Alpha-Hydroxy progesterone Caproate
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C57BL/6J小鼠与昆明小鼠NIAAA法酒精性肝病造模效果的比较
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作者 吕皓 林川 +3 位作者 陈红 杨晨晨 向欣 韩春梅 《塔里木大学学报》 2024年第3期43-48,共6页
为了对比C57BL/6J小鼠和昆明小鼠酒精性肝病模型建造效果及建模完成后续肝脏生化指标变化情况,为酒精性肝病的治疗研究提供基础依据,试验选择雌性C57BL/6J小鼠和昆明小鼠各36只,随机分为对照组(液体饲料+麦芽糊精)、建模16 d组与建模19 ... 为了对比C57BL/6J小鼠和昆明小鼠酒精性肝病模型建造效果及建模完成后续肝脏生化指标变化情况,为酒精性肝病的治疗研究提供基础依据,试验选择雌性C57BL/6J小鼠和昆明小鼠各36只,随机分为对照组(液体饲料+麦芽糊精)、建模16 d组与建模19 d组(液体饲料+酒精,n=12)。利用NIAAA法建造酒精性肝病小鼠模型,并分别于建模第16 d、建模第19 d取其血清及肝组织进行生化指标检测及病理切片观察。结果显示,C57BL/6J小鼠建模16 d组和建模19 d组与昆明小鼠建模16 d组的小鼠血清ALT、AST含量,肝脏MDA、TG含量均分别显著高于其对照组小鼠(P<0.05);而血清ALB含量、肝脏SOD活力显著低于其对照组小鼠(P<0.05)。C57BL/6J建模16 d组和建模19 d组小鼠的肝脏GSH含量和肝脏系数显著高于其对照组小鼠(P<0.05),但昆明小鼠建模19 d组除了肝脏SOD活力显著低于其对照组小鼠(P<0.05),其他指标均与其对照组小鼠无显著差异。病理切片结果表明,与对照组相比,建模16 d组2种小鼠肝细胞排列紊乱,肝细胞索断裂,肝细胞出现炎性浸润和脂肪液滴。C57BL/6J小鼠建模19 d组肝组织仍呈现病变,而昆明小鼠建模19 d组肝细胞已逐渐恢复正常排列。与昆明小鼠相比,C57BL/6J小鼠对于酒精的肝脏氧化应激损伤更严重,酒精性肝病模型更稳定。 展开更多
关键词 C57bl/6J小鼠 昆明小鼠 NIAAA法 酒精性肝病 生化指标 病理变化
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Differentiation of Osteoblast in vitro Is Regulated by Progesterone
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作者 陈璐璐 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1996年第2期83-86,共4页
The regulation of cellular differentiation by progesterone in fetal rat calvarial osteoblasts was investigated. Our results showed that cells cultured in the presence of progesterone had a 7% increase in the alkaline ... The regulation of cellular differentiation by progesterone in fetal rat calvarial osteoblasts was investigated. Our results showed that cells cultured in the presence of progesterone had a 7% increase in the alkaline phosphatase activity when compared to untreated cells. The concentration of osteocalcin in the conditioned medium from progesterone treated osteoblasts was 28% higher than that of untreated controls. In addition,administration of progesterone significantly enhanced the number and area of bone nodules. In conclusion, progesterone stimulates the differentiation of fetal rat calvarial osteoblastic cells in vitro 展开更多
关键词 fetal rat calvarial osteoblastic cells progesterone ALP activity osteocalcin bone nodule
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Cluster Analysis of the Roma-BZCAT Blazars
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作者 Dmitry O.Kudryavtsev Yulia V.Sotnikova +5 位作者 Vladislav A.Stolyarov Timur V.Mufakharov Valery V.Vlasyuk Margarita L.Khabibullina Alexander G.Mikhailov Yulia V.Cherepkova 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第5期117-139,共23页
Based on the collected multiwavelength data, namely in the radio(NVSS, FIRST, RATAN-600), IR(WISE),optical(Pan-STARRS), UV(GALEX), and X-ray(ROSAT, Swift-XRT) ranges, we have performed a cluster analysis for the blaza... Based on the collected multiwavelength data, namely in the radio(NVSS, FIRST, RATAN-600), IR(WISE),optical(Pan-STARRS), UV(GALEX), and X-ray(ROSAT, Swift-XRT) ranges, we have performed a cluster analysis for the blazars of the Roma-BZCAT catalog. Using two machine learning methods, namely a combination of PCA with k-means clustering and Kohonen's self-organizing maps(SOMs), we have constructed an independent classification of the blazars(five classes) and compared the classes with the known Roma-BZCAT classification(FSRQs, BL Lacs, galaxy-dominated BL Lacs, and blazars of an uncertain type) as well as with the high synchrotron peaked(HSP) blazars from the 3HSP catalog and blazars from the TeVCat catalog. The obtained groups demonstrate concordance with the BL Lac/FSRQ classification along with a continuous character of the change in the properties. The group of HSP blazars stands out against the overall distribution. We examine the characteristics of the five groups and demonstrate distinctions in their spectral energy distribution shapes. The effectiveness of the clustering technique for objective analysis of multiparametric arrays of experimental data is demonstrated. 展开更多
关键词 methods data analysis-galaxies active-(galaxies:)bl Lacertae objects GENERAL
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Oral Micronized or Parenteral Progesterone versus Health Education in the Prevention of Preterm Birth: A Single Blinded Randomized Controlled Trial
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作者 Atef M. M. Darwish Alaa E. M. Ismail +1 位作者 Maher S. Mohammad Salah A. E. Gobara 《Open Journal of Obstetrics and Gynecology》 2019年第5期612-623,共12页
The primary aim of this study was to evaluate the possible prophylactic role of progesterone in women with a history of spontaneous preterm birth (PTB) while the secondary aim was to compare oral or intramuscular prog... The primary aim of this study was to evaluate the possible prophylactic role of progesterone in women with a history of spontaneous preterm birth (PTB) while the secondary aim was to compare oral or intramuscular progesterone versus health education in such cases. Methods: A randomized, single blinded interventional randomized controlled trial was conducted. It comprised 90 cases with a history of PTB who were divided into 3 equal groups who received oral micronized progestogen capsule 200 mg daily (group A), parenteral 17 α-hydroxyprogesterone caproate 250 mg weekly IM injections (group B) or received health education including rest (group C) starting from 20 weeks till the end of 34 weeks of gestation. Results: This study included eligible 90 pregnant women at high risk of PTB who continued follow-up. For socio-demographic characteristics, there were no significant differences between the groups in respect to age, residence, education level, occupation, gravidity, parity and number of living children apart from significant difference between group A and C regarding mean patients’ age. Mode and place of delivery did not differ between the groups while gestational age at time of delivery was significantly better on using injectable than oral progesterone. Neonatal birth weight was significantly higher in group B if compared separately to groups A and C and was still significantly higher in group A if compared with group C. NICU admission rate was higher in group C if compared to group B or to the combined group A and B. Compliance was significantly higher in group B if compared to both group A and C and was significantly higher in the intervention group A and B if compared to group C. Conclusions: Progesterone supplementation has a significant role in prevention of PTB if compared with just health education. Progesterone injections expressed significantly better results than oral micronized progesterone in terms of prolongation of gestational age, better neonatal birth weight and less admission rate to the NICUs. 展开更多
关键词 PRETERM Birth ORAL INJECTAblE progesterone Health Education
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