期刊文献+
共找到34,221篇文章
< 1 2 250 >
每页显示 20 50 100
Isozyme analysis on progenes of somatic hybrids of Oryza sativa L.and O.officinalis
1
作者 TENG Sheng HU Zhanghua ZHANG Xueqin and YAN Qiusheng,CNRRI,Hangzhou 310006,China 《Chinese Rice Research Newsletter》 1996年第2期6-6,共1页
Some wild species of Oryza possess agronomi-cally useful traits such as disease/insect resis-tance and salt tolerance.However,the use ofwild Oryza species for rice improvement hasbeen hampered by the sexual incompatib... Some wild species of Oryza possess agronomi-cally useful traits such as disease/insect resis-tance and salt tolerance.However,the use ofwild Oryza species for rice improvement hasbeen hampered by the sexual incompatibility orsterility of hybrids obtained by conventionalmethods.We have used protoplast fusion as amethod to incorporate useful trait of wild O-ryza species into cultivated rice and~ obtainedsomatic hybrid plants between O.sativa and 展开更多
关键词 In Isozyme analysis on progenes of somatic hybrids of Oryza sativa l.and O.officinalis
下载PDF
Identification of a Cytoplasmic Male Sterile Line NEA in Brassica napus L.and Its Genetic Studies 被引量:10
2
作者 JIANG Liang-cai, PU Xiao-bin, ZHANG Qi-xing, CHEN Fang and ZHANG Jin-fang( The Crop Institute of the Sichuan Academy of Agricultural Sciences , Chengdu 610066 , P.R. China SichuanUniversity, Chengdu 610064 , P.R. China) 《Agricultural Sciences in China》 CAS CSCD 2002年第4期381-387,共7页
Male sterile NEA plants were identified in progenies of the radiated 92P x Aggregate-silique in Brassica napus L. in 1993. Their progeny plants from test crossing and open pollination were 100% male sterile. The doubl... Male sterile NEA plants were identified in progenies of the radiated 92P x Aggregate-silique in Brassica napus L. in 1993. Their progeny plants from test crossing and open pollination were 100% male sterile. The double-low male sterile lines JL-4 and JL-18 were bred through successive backcrossing of the double -low variety No.4 and No. 18 in Brassica napus L.to NEA. Restorer lines 6720 and 6722 with significant heterosis in F1 were developed. The results from investigating the restoring-ntaintaining relationship and inheritance of the restorer gene indicated that JL-4 and JL-18 were different from both PolCMS and Shan 2A type, and their restorer gene was controlled by a pair of dominant genie genes. 展开更多
关键词 Brassica napus L. Male sterile line Restorer line HEREDITY
下载PDF
Use of Support Vector Regression Based on Mean Impact Value Model to Identify Active Compounds in a Combination of Curcuma longa L.and Glycyrrhiza extracts 被引量:2
3
作者 Jianlan Jiang Qingjie Tan +2 位作者 Weifeng Li Xinyun Du Ningzhi Liu 《Transactions of Tianjin University》 EI CAS 2017年第3期237-244,共8页
A support vector regression based on the mean impact value (MIV) model was constructed to identify the bioactive compounds inhibiting proliferation of He La cells in a combination of turmeric (Curcuma longa L.)and liq... A support vector regression based on the mean impact value (MIV) model was constructed to identify the bioactive compounds inhibiting proliferation of He La cells in a combination of turmeric (Curcuma longa L.)and liquorice (Glycyrrhiza) extracts.The quantitative chemical fingerprint from 50 batches of turmeric and liquorice extracts was established using high performance liquid chromatography hyphenated to an ultraviolet visible detector.Qualitative results were obtained using ultra performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry.A total of 46 peaks (peaks 1–15 from turmeric and 16–46 from liquorice) were selected as "common peaks" for analysis.The inhibitory effect of the combined extracts on He La cells was measured by MTT (3- (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay.It was found that 15 compounds (peaks:8,12,30,24,46,11,14,9,3,1,44,18,7,45 and 43)possessing high absolute MIV exhibited a significant correlation with the cytotoxicity against He La cells; most of these have already been confirmed with potential cytotoxicity in previous research.The important potential application of the present model can be extended to help discover active compounds from complex herbal medicine prior to traditional bioassay-guided separation.It is considered that this could be a useful tool for redeveloping herbal medicine based on the use of these active compounds. 展开更多
关键词 CURCUMA longa L. GLYCYRRHIZA Active compound identification Support vector regression Mean IMPACT value
下载PDF
Aromatic compounds from Solanum nigrum L.and their antioxidant activities
4
作者 Wei Xu Ming Bai Xiaoxiao Huang 《Asian Journal of Traditional Medicines》 CAS 2020年第2期55-64,共10页
Solanum nigrum L.,belonging to the genus Solanum of Solanaceae family,is widely distributed in temperate and tropical regions of the world.It possesses the effects of clearing away heat and detoxification.A wide spect... Solanum nigrum L.,belonging to the genus Solanum of Solanaceae family,is widely distributed in temperate and tropical regions of the world.It possesses the effects of clearing away heat and detoxification.A wide spectrum of chemical constituents have been isolated from the Solanum nigrum L.,including lignans,steroids,etc.The structures of the eight compounds were determined by comprehensive spectroscopic analyses.It is noteworthy that compounds 1–4,6 and 8 have been isolated from Solanum nigrum L.for the first time.All compounds were evaluated for their antioxidant activities by ABTS and DPPH assays.Based on the results,Solanum nigrum L.could be used as a new natural antioxidant in biomedical applications. 展开更多
关键词 SOLANUM nigrum L. SOLANACEAE FAMILY AROMATIC COMPOUNDS ANTIOXIDANT activity
下载PDF
Pharmacognostic Identification of Euphorbia maculata L.and Its Related Species
5
作者 Jing HOU Li LI +3 位作者 Xiaotong JING Yuan LIANG Shaoqi LUO Yi CAI 《Medicinal Plant》 CAS 2021年第1期32-34,39,共4页
[Objectives]To make pharmacognostic identification of Euphorbia maculata L.and its related species.[Methods]The classical pharmacognostic identification method was adopted.[Results]The four main medicinal materials ar... [Objectives]To make pharmacognostic identification of Euphorbia maculata L.and its related species.[Methods]The classical pharmacognostic identification method was adopted.[Results]The four main medicinal materials are very similar,the fluff can be seen in E.maculata and Euphorbia thymifolia L.,but not in Euphorbia prostrata Ait.and Euphorbia taihsiensis(Chaw et Koutnik)Oudejians;the tissue structure is basically the same;except for E.taihsiensis without non-glandular hairs,the powder has secretory cells,laticifers,cells,calcium oxalate crystals,fibers,vessels,and seed coat fragments.Through ultrasonic extraction with 80%ethanol,extraction with isobutanol,extending with chloroform∶ethyl acetate∶formic acid(5∶3∶0.3),developing color with 3%aluminum trichloride ethanol solution,under ultraviolet light(365 nm),the fluorescent spots of the same color appeared on the corresponding position of the chromatogram of the reference substance(quercetin,kaempferol).[Conclusions]It is not easy to distinguish the four medicinal materials by character identification and microscopic identification,while the thin-layer chromatography(TLC)is more reliable. 展开更多
关键词 Euphorbia maculata L. Euphorbia thymifolia L. Euphorbia prostrata Ait. Euphorbia taihsiensis(Chaw et Koutnik)Oudejians Pharmacognostic identification
下载PDF
Medicinal and Edible Plant——Physalis alkekengi L.and Its Cultivation Techniques
6
作者 Nurbolat AIDARHAN Maimaitiaili TURSUNBAHE +2 位作者 Abulimiti YILI Geyu LIU Haji Akber AISA 《Medicinal Plant》 CAS 2022年第5期8-9,共2页
Botanical morphological characteristics of Physalis alkekengi L.is first introduced,and its medicinal and edible value is elaborated.Cultivation techniques of P.alkekengi L.are mainly introduced.The research aims to p... Botanical morphological characteristics of Physalis alkekengi L.is first introduced,and its medicinal and edible value is elaborated.Cultivation techniques of P.alkekengi L.are mainly introduced.The research aims to provide a certain basis for the better development and application of P.alkekengi L. 展开更多
关键词 Physalis alkekengi L. Dual use of medicine and food Application value Morphological character Cultivation technique
下载PDF
Research on the Origin of Mongolian Medicine Veratrum nigrum L.and Its Recent Research Progress
7
作者 Taogedunbaiyila Chun CHANG +2 位作者 Jiaqi YU Ning XU Liang XU 《Medicinal Plant》 CAS 2022年第6期109-112,共4页
On the basis of research on the origin of Mongolian medicine Veratrum nigrum L.,this paper summarizes the research situation of Mongolian medicine Veratrum nigrum L.from the aspects of clinical application,chemical co... On the basis of research on the origin of Mongolian medicine Veratrum nigrum L.,this paper summarizes the research situation of Mongolian medicine Veratrum nigrum L.from the aspects of clinical application,chemical composition,pharmacological action and toxicological action,so as to provide a reference basis for further research and further development and utilization of Mongolian medicine. 展开更多
关键词 Mongolian medicine Veratrum nigrum L. Research progress
下载PDF
Research progress on chemical constituents in Sophora alopecuroides L.and their pharmacological activities
8
作者 Bohan Yang Jing Wang +2 位作者 Xiaoxu Gao Jingming Jia Anhua Wang 《Asian Journal of Traditional Medicines》 CAS 2021年第5期309-322,共14页
Sophora alopecuroides L.,a perennial plant belonging to Leguminosae family,is used as medicinal materials to treat a variety of skin diseases.Its chemical components are complex and diverse,mainly including alkaloids ... Sophora alopecuroides L.,a perennial plant belonging to Leguminosae family,is used as medicinal materials to treat a variety of skin diseases.Its chemical components are complex and diverse,mainly including alkaloids and flavonoids.Modern pharmacological studies have found that the isolated compounds from S.alopecuroides have a variety of pharmacological activities.In particular,alkaloids represented by matrine,aloperine and oxymatrine have significant anti-inflammatory,anti-viral,anti-tumor,anti-bacterial and immunomodulatory activities.This paper summarized the chemical constituents and pharmacological activities of S.alopecuroides,aiming to provide the basis for further research. 展开更多
关键词 Sophora alopecuroides L. chemical components pharmacological activities
下载PDF
Network pharmacology-based virtual screening of active alkaloid ingredients from Piper nigrum L.and the potential targets against Parkinson’s disease
9
作者 Ye Chang Yuxi Wang +1 位作者 Xiaoxiao Huang Shaojiang Song 《Asian Journal of Traditional Medicines》 CAS 2021年第4期225-230,共6页
Parkinson’s disease(PD)is a common neurodegenerative disease.Despite a great deal of research on this disease,there is still no definitive treatment plan.Literature investigations have shown that Piper nigrum L.has a... Parkinson’s disease(PD)is a common neurodegenerative disease.Despite a great deal of research on this disease,there is still no definitive treatment plan.Literature investigations have shown that Piper nigrum L.has a protective effect on the nerve center.Therefore,network pharmacology was used in this study to investigate the therapeutic potential of P.nigrum for PD.As a result,six active alkaloid ingredients and four potential targets were obtained.This study laid the foundation for finding the lead compounds from P.nigrum to treat PD. 展开更多
关键词 Piper nigrum L. network pharmacology Parkinson’s disease
下载PDF
Essential Oils from Mentha viridis(L).L.and Mentha pulegium L.:Cytogenotoxic Effects on Human Cells
10
作者 Lucilene Fernandes Silva Maria das Gracas Cardoso +7 位作者 Paulo Sérgio Castilho Preté Maria Luisa Teixeira David Lee Nelson Maísa Lamounier Magalhaes Vanuzia Rodrigues Fernandes Ferreira Rafaela Vieira Souza Luana Isac Soares Silvana Marcussi 《American Journal of Plant Sciences》 2017年第6期1423-1437,共15页
The essential oils from Mentha viridis (L). L. and Mentha pulegium L. were studied to assess their inhibitory potential on phospholipase from snake venoms and to determine their cytogenotoxic action on human cells. Th... The essential oils from Mentha viridis (L). L. and Mentha pulegium L. were studied to assess their inhibitory potential on phospholipase from snake venoms and to determine their cytogenotoxic action on human cells. These essential oils were able to inhibit the breakdown of phospholipids induced by venoms of snakes of the Bothrops genus. Both oils presented hemolytic activity, although the Mentha viridis (L). L. oil induced hemolysis only at the highest concentrations (14.6 and 29 μL&#183mL-1). The essential oil from M. viridis induced 3.9;8.6 and 16.2 times greater damage to human leukocyte DNA than that observed with the positive control (100 μg&#183μL-1 doxorubicin) at concentrations of 0.25;0.5 and 1.0 μL&#183mL-1, respectively. A similar effect was observed for the oil from M. pulegium (2.1, 2.5 and 15.8 times greater damage). The results extend the characterization of these essential oils and demonstrate their potential use in industries. 展开更多
关键词 Essential Oils Mentha viridis(L).L. Mentha pulegium L. HEMOLYSIS Comet Assay
下载PDF
The hypoglycemic effect of Lagerstroemia indica L.and Lagerstroemia indica L.f.alba(Nichols.)Rehd.in vitro and in vivo
11
作者 Meifang Chang Adel F.Ahmed Lili Cui 《Journal of Future Foods》 2023年第3期273-277,共5页
Lagerstroemia indica L.has a high medicinal value,its bark,leaves and flowers can be used as medicine.Its flowers are reddish,purple,or white,thereinto,the white one is called L.indica Linn.f.alba(Nichols.)Rehd.,which... Lagerstroemia indica L.has a high medicinal value,its bark,leaves and flowers can be used as medicine.Its flowers are reddish,purple,or white,thereinto,the white one is called L.indica Linn.f.alba(Nichols.)Rehd.,which is a forma of L.indica.In this paper,the hypoglycemic effects of different extracts from flowers of L.indica(LIF)and L.indica L.f.alba(Nichols.)Rehd.(LIAF)were investigated byα-glucosidase inhibitory method in vitro and alloxan-induced diabetic mice model in vivo,respectively.The results in vitro showed that ethyl acetate extracts(EA)of LIF and LIAF(IC_(50)=4.45 and 4.09µg/mL,resepectively)had the highest inhibitory activity ofα-glucosidase,and followed by n-butyl alcohol extracts(BU)(IC_(50)=17.01 and 14.58µg/mL,respectively),and the last was petroleum ether extracts(PE)(IC_(50)=103.29 and 112.47µg/mL,respectively),the activities of all extracts were higher than that of the positive control(acarbose,IC_(50)=1278.83µg/mL).The results in vivo showed that compared with the model control group,each dose group of LIF could significantly(P<0.05,P<0.01 or P<0.001)decrease fasting blood glucose,total cholesterol(TC)level and malondialdehyde(MDA)content in diabetic mice and increase superoxide dismutase(SOD)level(P<0.05)in serum.Partial dose groups of LIF could significantly(P<0.05)decrease postprandial blood glucose,triglyceride(TG)and increase liver glycogen content.Each dose group of LIAF could significantly(P<0.05,P<0.01 or P<0.001)decrease fasting blood glucose,TC level and increase SOD level in serum.Partial dose groups of LIAF could significantly(P<0.05)decrease TG,MDA level and increase liver glycogen content.These results indicate that LIF and LIAF had effective prevention and treatment effects on the development for diabetes. 展开更多
关键词 Lagerstroemia indica L. Lagerstroemia indica L.f.alba(Nichols.)Rehd. α-Glucosidase inhibitory activity DIABETES
原文传递
基于SNP标记的小麦品种遗传相似度及其检测准确度分析
12
作者 许乃银 金石桥 +7 位作者 晋芳 刘丽华 徐剑文 刘丰泽 任雪贞 孙全 许栩 庞斌双 《作物学报》 CAS CSCD 北大核心 2024年第4期887-896,共10页
遗传相似度检测的准确度估计是对SNP标记法在农作物品种检测体系中应用的必要补充和完善。本研究基于2021年小麦品种SNP标记法跨实验室协同验证实验数据,分析了该方法的检测准确度及在品种间的遗传相似度。分析结果表明:(1)10个实验室... 遗传相似度检测的准确度估计是对SNP标记法在农作物品种检测体系中应用的必要补充和完善。本研究基于2021年小麦品种SNP标记法跨实验室协同验证实验数据,分析了该方法的检测准确度及在品种间的遗传相似度。分析结果表明:(1)10个实验室对55组小麦品种组合的标记位点相似度检测的总体准确度约为98%。(2)GGE双标图的品种遗传关系功能图显示,7组小麦品种的组内遗传相似度在95%以上,其余组合的遗传相似度较低。(3)依据GGE双标图的“正确度-精确度”功能图和“准确度排序”功能图,发现洛旱7号/洛旱11等品种组合的相似度检测准确度较高,晋麦47/临抗11的检测准确度一般,而济麦22/婴泊700的检测准确度较差。(4)10个实验室的检测准确度存在显著差异,其中2个实验室检测的正确度、精确度和准确度表现显著差于其余实验室。(5)各实验室检测正确度的容许误差分布于1.3%~1.9%之间,平均为1.5%;准确度的容许误差分布于1.5%~2.0%之间,平均为1.7%。其中,Lab2和Lab3的检测正确度和准确度的容许误差显著差于其余实验室。本研究构建了SNP标记法对品种相似性检测的准确度统计模型,分析了品种组合和实验室的检测准确度及其容许误差,采用GGE双标图方法对检测正确度、精确度和准确度进行可视化分析,验证了各实验室对品种位点相似性检测的准确度和可靠性,为SNP标记法在农作物品种遗传相似性检测中的准确度评价提供了理论支持和应用范例。 展开更多
关键词 小麦(Triticum aestivum L.) GGE双标图 SNP标记 遗传相似度 位点相似度 准确度
下载PDF
SLC6A8通过BNIP3L调控线粒体自噬促进肝癌细胞增殖
13
作者 路远 唐俊 +4 位作者 李文川 许佐明 罗宗将 马嘉盛 浦涧 《海南医学院学报》 CAS 北大核心 2024年第2期88-93,99,共7页
目的:探讨SLC6A8通过BNIP3L调控线粒体自噬对肝癌细胞增殖的影响。方法:通过TCGA数据库分析SLC6A8基因在肝癌组织中的表达情况,并与BNIP3L表达进行相关性分析。使用RT-PCR和Western blot技术检测SLC6A8过表达人肝癌Huh-7及Hep3B细胞中SL... 目的:探讨SLC6A8通过BNIP3L调控线粒体自噬对肝癌细胞增殖的影响。方法:通过TCGA数据库分析SLC6A8基因在肝癌组织中的表达情况,并与BNIP3L表达进行相关性分析。使用RT-PCR和Western blot技术检测SLC6A8过表达人肝癌Huh-7及Hep3B细胞中SLC6A8和BNIP3L的表达。免疫荧光标记和CCK-8检测法用于观察SLC6A8过表达人肝癌Huh-7及Hep3B细胞线粒体自噬和细胞增殖率。使用CCK-8检测法评估在沉默BNIP3L后SLC6A8过表达人肝癌Huh-7及Hep3B细胞增殖率。结果:SLC6A8在肝癌组织中显著高表达,并与BNIP3L表达呈正相关。SLC6A8过表达可显著促进线粒体自噬和人肝癌Huh-7及Hep3B细胞的增殖。此外,SLC6A8过表达显著促进BNIP3L mRNA和蛋白的表达。沉默BNIP3L后,SLC6A8过表达对肝癌细胞增殖的促进作用被逆转。结论:SLC6A8在肝癌组织中的高表达与BNIP3L有正相关性,且SLC6A8的过表达能促进线粒体自噬和肝癌细胞的增殖,沉默BNIP3L可逆转SLC6A8过表达对肝癌细胞增殖促进作用。这为肝癌的治疗提供了新的靶点和策略。 展开更多
关键词 线粒体自噬 SLC6A8 BNIP3L 肝细胞癌
下载PDF
CDR132L改善高血压合并高脂血症小鼠血管重构和功能
14
作者 林俊敏 梁风金 +3 位作者 吴莹 许开祖 吴梅芳 林丽明 《中国动脉硬化杂志》 CAS 2024年第4期303-309,共7页
[目的]观察CDR132L(miR-132反义核苷酸)对高血压合并高脂血症小鼠血管重构和功能的影响,并探究其可能的作用机制。[方法]随机选择30只8周龄雄性C57BL/6小鼠,分为三组:对照组、模型组和CDR132L组,每组10只。对照组接受标准饲料喂养,模型... [目的]观察CDR132L(miR-132反义核苷酸)对高血压合并高脂血症小鼠血管重构和功能的影响,并探究其可能的作用机制。[方法]随机选择30只8周龄雄性C57BL/6小鼠,分为三组:对照组、模型组和CDR132L组,每组10只。对照组接受标准饲料喂养,模型组和CDR132L组给予N-硝基-L-精氨酸甲酯(L-NAME)和高脂食物联合喂养来诱导高血压和高脂血症。CDR132L组给予20 mg/kg CDR132L腹腔注射,1次/周,连续6周,对照组和模型组腹腔注射相同剂量的生理盐水溶液。尾套法测量小鼠尾动脉收缩压和舒张压,血脂、血糖检测由全自动生化分析仪完成,HE染色观察胸主动脉结构,血管环试验观察小鼠胸主动脉内皮依赖性舒张反应,定量基因扩增检测胸主动脉miR-132表达水平,Western blot检测胸主动脉Gab1和内皮型一氧化氮合酶(eNOS)蛋白表达水平。[结果]与对照组相比,模型组小鼠收缩压、舒张压、血清甘油三酯、血清总胆固醇和体质量均明显升高(P<0.05),胸主动脉内膜凹凸不平,血管壁厚度不均,中膜平滑肌细胞的排列呈现不规则状态,血管壁上存在大量脂肪积聚,胸主动脉内皮依赖性舒张反应减低(P<0.05),胸主动脉miR-132表达水平明显增加(P<0.05),Gab1和eNOS蛋白表达水平明显降低(P<0.05)。与模型组相比,CDR132L组小鼠收缩压、舒张压、血清甘油三酯、血清总胆固醇和体质量均无统计学差异(P>0.05),胸主动脉管腔内膜较完整光滑,血管壁厚度较均一,中膜平滑肌细胞的排列较为有序,血管壁仅存在少量脂肪积聚,胸主动脉内皮依赖性舒张反应增强(P<0.05),胸主动脉miR-132表达水平明显降低(P<0.05),Gab1和eNOS蛋白表达水平明显增加(P<0.05)。[结论]CDR132L能改善高血压合并高脂血症小鼠血管重构及内皮依赖性舒张功能,这一作用可能与其降低胸主动脉miR-132表达水平,进而上调胸主动脉Gab1和eNOS蛋白表达水平有关。 展开更多
关键词 CDR132L miR-132 高血压 高脂血症 血管重构 内皮舒张功能
下载PDF
骨质疏松患者EQ⁃5 D⁃5L量表健康相关影响因素分析
15
作者 杨帆 田利民 +6 位作者 余静 张娜文 杨建宁 洪豆豆 温子英 杨瑞霞 张琦 《中国骨质疏松杂志》 CAS CSCD 北大核心 2024年第3期341-347,共7页
目的探讨住院骨质疏松症患者的健康相关生命质量状况及健康效用值,并分析其影响因素。方法以甘肃省人民医院住院骨质疏松症患者为调查对象,收集患者一般资料、检测骨代谢标志物,测量腰椎和髋部骨密度,评估患者跌倒风险、预测骨折、评估... 目的探讨住院骨质疏松症患者的健康相关生命质量状况及健康效用值,并分析其影响因素。方法以甘肃省人民医院住院骨质疏松症患者为调查对象,收集患者一般资料、检测骨代谢标志物,测量腰椎和髋部骨密度,评估患者跌倒风险、预测骨折、评估生命质量并计算健康效用值。采用Mann⁃Whitney检验及Kruskal⁃Wallis检验进行单因素分析,并用Tobit回归模型分析研究对象生命质量的影响因素。结果最终纳入241名住院骨质疏松症患者为研究对象,健康效用值为0.876(0.728~0.942)。单因素分析显示,年龄、文化程度、跌倒风险、居住地、吸烟、既往用抗骨松药物、低创骨折史、FRAX评分、左髋部T值、钙与骨质疏松患者健康效用值相关(P<0.05);Tobit回归模型结果显示,文化程度高(小学:β=0.119,P=0.043;初中:β=0.113,P=0.044;高中或中专或技校β=0.171,P=0.002)是生命质量的保护因素,跌倒风险高(中风险β=-0.138,P<0.001;高风险β=-0.316,P<0.001)、低创骨折史(β=-0.190,P<0.001)、FRAX评分为高危(β=-0.088,P=0.027)是生命质量的危险因素。结论与普通人群相比,住院骨质疏松症患者健康效用值下降,表明健康相关生命质量差。文化程度低、跌倒风险高、骨折以及FRAX评分高危的患者生命质量较差。为提高患者生命质量,应该加强对该类患者的健康宣教,预防跌倒并积极主动的进行干预,防止骨折及再骨折的发生。 展开更多
关键词 骨质疏松症 健康相关生命质量 健康效用值 EQ⁃5 D⁃5L
下载PDF
外源茉莉酸甲酯对BNS366雄性育性的影响
16
作者 刘海英 陈芸 +6 位作者 茹振钢 陈向东 孔陈源 黄康兴 冯必得 马峥鸣 杨轩林 《麦类作物学报》 CAS CSCD 北大核心 2024年第5期559-566,共8页
为探究外源茉莉酸甲酯(methyl jasmonate,MeJA)对小麦温敏雄性不育系BNS366雄性育性的影响,以BNS366及其近等基因系郑麦366为试验材料,在正常秋季播种(2020年10月12日)和晚播(2020年12月2日)条件下,分别于2021年3月22日和3月31日开始至... 为探究外源茉莉酸甲酯(methyl jasmonate,MeJA)对小麦温敏雄性不育系BNS366雄性育性的影响,以BNS366及其近等基因系郑麦366为试验材料,在正常秋季播种(2020年10月12日)和晚播(2020年12月2日)条件下,分别于2021年3月22日和3月31日开始至开花期前,设置0(清水,对照)、50、100、200、300、400和500μmol·L^(-1) MeJA(水溶液,喷施)7个处理,比较分析了不同处理间花粉可育率和自交结实率的差异。结果表明:在正常秋季播种条件下,郑麦366花粉可育率、国内法自交结实率和国际法自交结实率分别为86.31%、70.36%和112.22%,在晚播条件下分别为82.53%、92.53%和166.18%,均正常可育;在正常秋季播种条件下,200μmol·L^(-1) MeJA处理的国际法自交结实率为70.15%,比对照显著降低了42.07个百分点;在晚播条件下,200、300和500μmol·L^(-1) MeJA处理的国内法自交结实率分别为74.71%、74.01%和73.45%,比对照显著降低了17.82、18.52和19.08个百分点;在两个播期下,郑麦366其他浓度MeJA处理的上述3个指标与对照差异均不显著。在正常秋季播种条件下,BNS366花粉可育率为零,达到全不育水平,国内法自交结实率和国际法自交结实率均为0.24%,100μmol·L^(-1) MeJA处理的花粉可育率为88.25%,达到正常可育水平,国内法自交结实率和国际法自交结实率分别为56.41%和94.01%,能正常结实,与对照差异达到显著水平;在晚播条件下,BNS366的上述3个指标分别为51.72%、41.23%和93.08%,正常可育,100μmol·L^(-1) MeJA处理的国际法自交结实率为39.72%,比对照显著降低了53.36个百分点;在两个播期下,BNS366其他浓度MeJA处理的上述3个指标与对照差异均不显著。由此说明,在2020-2021年,外源MeJA对郑麦366和BNS366可育植株的雄性育性可能具有降低效应,对BNS366不育植株的雄性不育性具有较强恢复效应。 展开更多
关键词 普通小麦(Triticum aestivum L.) 温敏雄性不育 茉莉酸甲酯 花粉可育率 自交结实率
下载PDF
一种L波段300W GaN脉冲功率模块
17
作者 董四华 刘英坤 +1 位作者 高永辉 秦龙 《半导体技术》 CAS 北大核心 2024年第6期555-560,共6页
随着第三代半导体GaN器件技术的不断发展,GaN高电子迁移率晶体管(HEMT)在电子系统中逐步得到了广泛应用。研制了一款小型化L波段300 W GaN脉冲功率模块。研发了满足高压脉冲工作条件的GaN HEMT芯片,采用负载牵引技术进行了器件大信号阻... 随着第三代半导体GaN器件技术的不断发展,GaN高电子迁移率晶体管(HEMT)在电子系统中逐步得到了广泛应用。研制了一款小型化L波段300 W GaN脉冲功率模块。研发了满足高压脉冲工作条件的GaN HEMT芯片,采用负载牵引技术进行了器件大信号阻抗参数提取,并以此为基础设计了小型化匹配网络进行阻抗变换。基于高压驱动芯片和开关器件芯片设计了小型化高压脉冲调制电路。测试结果表明,在工作频率990~1130 MHz、工作电压50 V、脉冲宽度100μs、占空比10%下,功率模块脉冲输出功率大于300 W,功率附加效率大于53%,功率增益大于38 dB。功率模块尺寸为30 mm×30 mm×8 mm。 展开更多
关键词 GaN高电子迁移率晶体管(HEMT) 负载牵引技术 高压脉冲调制 L波段 功率模块
下载PDF
苦瓜皂苷L调控PI3K/AKT通路促进内皮祖细胞增殖能力和内皮功能的实验研究
18
作者 黄建明 刘滴 +1 位作者 金道群 朱定君 《中西医结合心脑血管病杂志》 2024年第10期1768-1772,共5页
目的:探讨苦瓜皂苷L对内皮祖细胞(EPC)增殖能力和内皮功能的作用及机制。方法:体外分离、培养、鉴定外周血EPC。使用不同浓度苦瓜皂苷L处理EPC 24 h后,应用细胞计数试剂盒(CCK-8)法检测各组细胞活力。使用AutoDock Tools 5.6软件,分别... 目的:探讨苦瓜皂苷L对内皮祖细胞(EPC)增殖能力和内皮功能的作用及机制。方法:体外分离、培养、鉴定外周血EPC。使用不同浓度苦瓜皂苷L处理EPC 24 h后,应用细胞计数试剂盒(CCK-8)法检测各组细胞活力。使用AutoDock Tools 5.6软件,分别以磷脂酰肌醇3-激酶(PI3K)和蛋白激酶B(AKT)为受体,以药物分子苦瓜皂苷L为配体采用盲对接法进行分子对接。使用PI3K/AKT抑制剂LY294002和最佳使用浓度的苦瓜皂苷L单独或同时处理EPC 24 h后检测各组细胞活力和磷酸化PI3K(p-PI3K)、磷酸化AKT(p-AKT)及磷酸化内皮型一氧化氮合酶(p-eNOS)表达水平。结果:与对照组比较,苦瓜皂苷L呈剂量依赖性地促进EPC增殖,且40μmol/L的苦瓜皂苷L是最佳药物浓度。与对照组比较,LY294002可下调EPC细胞活力,苦瓜皂苷L可上调细胞活力。与苦瓜皂苷L组比较,共同使用苦瓜皂苷L和LY294002可降低细胞活力。分子对接结果显示,苦瓜皂苷L与PI3K和AKT均存在直接作用,形成稳定的锁钥结构。与对照组比较,LY294002可显著下调p-PI3K、p-AKT和p-eNOS蛋白水平;苦瓜皂苷L可上调p-PI3K、p-AKT和p-eNOS蛋白水平。与苦瓜皂苷L组比较,使用苦瓜皂苷L和LY294002可降低p-PI3K、p-AKT和p-eNOS蛋白水平。结论:苦瓜皂苷L通过PI3K/AKT信号通路靶向调节EPC的增殖能力,进而上调内皮型一氧化氮合酶(eNOS)活化水平以促进EPC内皮功能。 展开更多
关键词 内皮祖细胞 苦瓜皂苷L 细胞增殖 内皮功能 实验研究
下载PDF
316L不锈钢掺杂SiC环状同轴送粉TIG熔覆层组织结构与性能
19
作者 高辉 周灿丰 +1 位作者 胡晓慧 李文龙 《焊接学报》 EI CAS CSCD 北大核心 2024年第4期49-56,I0006,共9页
TIG熔覆是经济高效的表面修复方法,与传统的预置粉末法相比,同轴送粉法具有优良的适应性,但是试验研究相对较少.自主设计制造了环状同轴送粉TIG熔覆焊枪,与管状同轴送粉TIG熔覆焊枪相比,制造的熔覆层不存在熄弧位置凹坑、焊缝不够平直... TIG熔覆是经济高效的表面修复方法,与传统的预置粉末法相比,同轴送粉法具有优良的适应性,但是试验研究相对较少.自主设计制造了环状同轴送粉TIG熔覆焊枪,与管状同轴送粉TIG熔覆焊枪相比,制造的熔覆层不存在熄弧位置凹坑、焊缝不够平直以及焊缝熔宽不一致等问题,而且具有更高的熔覆效率.结果表明,采用优化的焊接热输入、送粉量和SiC含量参数匹配,在316L不锈钢表面进行环状同轴送粉TIG熔覆,获得了外观优良的单层单道熔覆层、单层多道熔覆层.对熔覆层进行显微硬度测量、微观组织及元素成分分析、宏观电化学腐蚀试验、微区电化学腐蚀试验以及耐磨性能测试,并与母材进行了比对,环状同轴送粉TIG熔覆导入的SiC粉末有效地提升了熔覆层的耐蚀性与耐磨性. 展开更多
关键词 环状同轴送粉TIG熔覆 316L不锈钢 掺杂SiC 耐蚀性 耐磨性
下载PDF
基于重加权L1的ATpV正则化叠前反演方法
20
作者 潘树林 陈耀杰 +2 位作者 尹成 苟其勇 张洞君 《西南石油大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期13-26,共14页
地震叠前反演能够准确获取地下储层介质的各类参数,是油气的勘探与开发中重要技术之一。然而,地震反演是典型的病态问题,为了克服此问题,通常使用正则化约束目标函数,来减轻反演问题的病态性。但是正则化约束忽略了地层边界的振幅信息,... 地震叠前反演能够准确获取地下储层介质的各类参数,是油气的勘探与开发中重要技术之一。然而,地震反演是典型的病态问题,为了克服此问题,通常使用正则化约束目标函数,来减轻反演问题的病态性。但是正则化约束忽略了地层边界的振幅信息,使用重加权方法可以很好地克服这一问题,更好地恢复稀疏性。提出了一种基于重加权L1的ATpV正则化叠前三参数反演方法(ATpV-L1方法),首次将重加权L1方法与ATpV方法结合,并引入到叠前反演中。采用交替方向乘子算法(ADMM)建立反演框架,对目标函数进行分块优化,有效提高了收敛速度。首先,介绍ATpV-L1方法,建立了基于ATpV-L1的叠前反演目标函数;然后,应用理论模拟数据对比新方法和ATpV方法反演结果,验证了方法的效果;最后,使用实际数据进行实验分析,进一步验证了ATpV-L1方法的反演精度及可行性。实验结果表明,提出的ATpV-L1方法可以有效恢复反演结果的稀疏性,提高反演精度。 展开更多
关键词 重加权L1方法 ATpV正则化 叠前反演 稀疏约束 交替方向乘子法 误差分析
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部