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Morphology and morphometry of two hybridizing buntings at their hybrid zone in northern Iran reveal intermediate and transgressive morphotypes
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作者 Ali Gholamhosseini Mansour Aliabadian +1 位作者 Till Topfer Glenn-Peter Sætre 《Avian Research》 SCIE CSCD 2023年第4期523-532,共10页
The closely related Black-headed Bunting(Emberiza melanocephala,a western Palearctic lineage)and Red-headed Bunting(Emberiza bruniceps,an eastern Palearctic lineage)hybridize and replace each other south of the Caspia... The closely related Black-headed Bunting(Emberiza melanocephala,a western Palearctic lineage)and Red-headed Bunting(Emberiza bruniceps,an eastern Palearctic lineage)hybridize and replace each other south of the Caspian Sea.The parental species have distinct phenotypes and therefore morphology is useful for assessing hybridization in the contact zone.In the years of 1940 and 1977,quite a few hybrids were collected and studied morphologically.Since then,the hybrid zone appears to have expanded westwards,but there has been a time gap in the collection of morphological data.Here we reanalyze bunting specimens morphologically and compare the historical data with recent data.Morphometric and phenotypic traits from three time periods(1940,1977 and recent)were studied to assess phenotypic variation of hybrids,pattern of hybridization,and transgressive traits in the hybrid zone.Our results show that most of the birds in the hybrid zone exhibit intermediate phenotypes(both colors and morphometric characters),ranging from the pure phenotype of either of the parental species.However,hybridization has also produced novel phenotypes not seen in any of the parents.Using a canonical discriminant function analysis,the morphometric characters separated each parental species and the hybrids quite well.Our results showed morphometric intermediacy of hybrids in accordance with phenotypes.We observe a time trend in which recent hybrids are more similar to Red-headed Buntings phenotypically compared to historical samples.This pattern is likely a signature of a westward expansion of the Red-headed Bunting into the breeding range of the Black-headed Bunting. 展开更多
关键词 bunting HYBRIDIZATION Intermediate phenotypes Transgressive traits
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Bunte法制备氧乐果 被引量:4
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作者 孙致远 黄润秋 +2 位作者 陈其杰 柴有新 钱宝英 《农药》 CAS 北大核心 1990年第1期16-17,共2页
氧乐果1959年发现杀虫活性,1967年西德拜耳公司试制生产。此药具有强烈的触杀作用和内渗作用,是较理想的根、茎内吸传导性杀螨、杀虫剂,特别适于防治刺吸性害虫,效果优于乐果和内吸磷,不易产生抗性,并可降低易产生抗性的拟除虫菊酯的抗... 氧乐果1959年发现杀虫活性,1967年西德拜耳公司试制生产。此药具有强烈的触杀作用和内渗作用,是较理想的根、茎内吸传导性杀螨、杀虫剂,特别适于防治刺吸性害虫,效果优于乐果和内吸磷,不易产生抗性,并可降低易产生抗性的拟除虫菊酯的抗性。因此,氧乐果在国内外越来越受欢迎,需求量不断扩大。 展开更多
关键词 氧乐果 杀虫剂 bunte法
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Bunte盐法合成巯基乙酸异辛酯 被引量:8
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作者 彭辉 揭嵘 刘利君 《化学工业与工程》 CAS 1994年第2期42-45,共4页
本文以氯乙酸、异辛醇和硫代硫酸钠为主要原料,采用Bunte盐法,合成了巯基乙酸异辛酯。通过实验,确定了工艺流程,选取了最佳的工艺条件。并对合成氯乙酸异辛酯的酯化反应进行了研究。
关键词 bunte盐 巯基 乙酸异辛酯 合成
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用Bunte Salts法合成苯甲醛二正丁硫醇缩醛的研究 被引量:4
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作者 余爱农 胡家鑫 +2 位作者 张庆 杨坤国 孙宝国 《精细石油化工》 CAS CSCD 北大核心 1999年第2期31-33,共3页
以苯甲醛、硫代硫酸钠和溴代正丁烷为原料 ,用 Bunte Salts法合成苯甲醛二正丁硫醇缩醛。较好的反应条件是 :Bunte Salts与苯甲醛的摩尔比为 3.3∶ 1 ,催化剂浓盐酸的用量为 7.5m L,回流反应 9h。在该条件下产率达 79.5% ,并用 IR、1
关键词 bunteSalts法 合成 苯甲醛二正丁硫醇缩醛 香料
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Jankowski’s Bunting (Emberiza jankowskii): current status and conservation 被引量:7
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作者 王海涛 姜云垒 高玮 《Chinese Birds》 2010年第4期251-258,共8页
Jankowski’s Bunting (Emberiza jankowskii) is a small bird with narrow distribution ranges. It has experienced a drastic population decline during recent years and vanished from most of its historic breeding sites. It... Jankowski’s Bunting (Emberiza jankowskii) is a small bird with narrow distribution ranges. It has experienced a drastic population decline during recent years and vanished from most of its historic breeding sites. It has been recently up-graded as Endangered in the IUCN Red List of globally threatened species. By integrating unpublished data of field surveys conducted by us and published information on the species, we provide information on the status of distribution, breeding biology of the remaining population at the Dagang Forest Farm, population trends at currently known breeding sites, selection of breeding habitats and threats faced by the Jankowski’s Bunting. In light of its current status we also suggest ways and future research work related to protecting this bird species. 展开更多
关键词 Jankowski’s bunting DISTRIBUTION BREEDING population trend CONSERVATION
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用Bunte Salts法合成正丁醛二正丁硫醇缩醛的研究 被引量:5
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作者 余爱农 杨坤国 +2 位作者 黄在银 李佳凤 孙宝国 《香料香精化妆品》 CAS 北大核心 1998年第4期3-4,21,共3页
以正丁醛、硫代硫酸钠和溴代正丁烷为原料,用BunteSalts法合成正丁醛二正丁硫醇缩醛。较好的反应条件是:按本文实验量加入催化剂浓盐酸1.5mL,回流反应时间为9h。在该条件下反应产率达82.6%,用IR、1HNMR证实了其结构。
关键词 bunteSalts法 合成 正丁醛二正丁硫醇缩醛 香料
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Bunte盐法合成巯基乙酸异辛酯的工艺研究 被引量:1
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作者 王彦军 《有色矿冶》 2015年第1期23-24,27,共3页
主要论述了利用Bunte盐法合成巯基乙酸,并使用乙醚与异辛醇协同萃取工艺制取巯基乙酸负载有机相,再经过粗馏酯化、精馏提纯得到高纯度巯基乙酸异辛酯的合成工艺。
关键词 bunte盐法 巯基乙酸 协同萃取 粗馏 精馏 巯基乙酸异辛酯
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Bunte盐法制备巯基乙酸实验合成新方法
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作者 赵若冬 《兰州石化职业技术学院学报》 2006年第1期3-4,共2页
采用氯乙酸和碳酸钠反应生成氯乙酸钠,控制氯乙酸钠溶液PH值为8~9,在70—75℃下与等摩尔硫代硫酸钠反应生成Bunte盐,加入反应物重量10%的硫酸,控制温度为80~90℃,时间为80min进行酸化反应;再加入反应物重量2%的Zn粉在40~50... 采用氯乙酸和碳酸钠反应生成氯乙酸钠,控制氯乙酸钠溶液PH值为8~9,在70—75℃下与等摩尔硫代硫酸钠反应生成Bunte盐,加入反应物重量10%的硫酸,控制温度为80~90℃,时间为80min进行酸化反应;再加入反应物重量2%的Zn粉在40~50℃下还原80min,得到粗产品;萃取、精馏后巯基乙酸纯度可达98.6%,收率可达到89.7%。 展开更多
关键词 巯基乙酸 bunte盐 萃取 精馏
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Bunte盐法合成巯基醋酸工艺研究 被引量:9
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作者 彭辉 揭嵘 刘利君 《湘潭大学自然科学学报》 CAS CSCD 1994年第1期90-93,99,共5页
巯基醋酸是一种用途非常广泛的精细化工产品.本文研究了以氯乙酸钠和硫代硫酸钠为主要原料,采用Bunte盐法合成了巯基醋酸,并对各工艺条件进行了讨论.认为该法成本低、生产过程简便、易操作.生产灵活性大,且几乎无污染.
关键词 bunte盐 合成 巯基醋酸
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Assessment of Risk of Establishment of Wheat Dwarf Bunt (Tilletia controversa) in China
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作者 JIAWen-ming ZHOU Yi-lin +4 位作者 DUAN Xia-yu LUO Yong DING Sheng-li CAO Xue-ren Bruce D L Fitt 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第1期87-94,共8页
Wheat dwarf bunt, caused by Tilletia controversa Kühn (TCK), is an important quarantine wheat disease throughout the world. Based on published research results of the biology and the epidemiology of the disease... Wheat dwarf bunt, caused by Tilletia controversa Kühn (TCK), is an important quarantine wheat disease throughout the world. Based on published research results of the biology and the epidemiology of the disease, the main factors including temperature, humidity, snow cover, and their parameters relating to teliospore germination, infection and epidemics of TCK were determined. The geophytopathological models for the risk analysis of wheat dwarf bunt establishment were modified. Fifty-year meteorologic data from about 500 weather stations in China were used to calculate the probabilities of TCK establishment in different geographic sites with the models. The map that displays the establishment risk of TCK in winter wheat growing regions in China was generated by using geographical information system (GIS). The zones showing high, moderate, low, and very low, including no risk, of TCK establishment accounted for 27.33, 27.69, 38.12, and 6.86% of total winter wheat growing areas in China, respectively. These results will provide useful information to formulate quarantine regulations and wheat importation policy in China. 展开更多
关键词 wheat dwarf bunt geophytopathological model geographical information system risk analysis
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Sexual dimorphism and sex-differential migration of Little Buntings(Emberiza pusilla)at an East Asian stopover site
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作者 Sook-Young Cho Hyun-Young Nam +1 位作者 Se-Young Park Chang-Yong Choi 《Avian Research》 SCIE CSCD 2022年第1期87-93,共7页
Sex differences in morphology provide key information for understanding a species'morphological adaptations in relation to the evolution of sexual selection.In migratory birds,morphological traits have adapted to ... Sex differences in morphology provide key information for understanding a species'morphological adaptations in relation to the evolution of sexual selection.In migratory birds,morphological traits have adapted to long-distance travel,and sexual dimorphism is typically related to sex-differential migration phenology.Little Buntings(Emberiza pusilla)have one of the longest migrations and are the least dichromatic species among the Emberiza buntings.In this study,we measured sexual size dimorphism and sexual dichromatism of Little Buntings in relation to the spring arrival dates at a stopover site in Korea.Wing length was the most important predictor for identifying sex;the wings of males were longer than those of females.Males also had a significantly stronger chestnut color of the head feathers than females,but this color difference was more prominent in the spring than in the fall.Males arrived earlier than females by four days.Arrival dates correlated with both size and color,but unlike other bunting species previously studied in the same area,there was no clear sex-differential trend in the relationship between arrival date and morphological characteristics.Seasonal differences in the degree of sexual dichromatism suggest that chestnut plumage coloration can be used as a social or sexual signal of males in the breeding season.The correlation of size and color to early arrival regardless of sex may indicate that a preference for assortative mating exists or that a sex-differential migration strategy is not clearly defined in the early stages of northward migration.Our findings on the sexual dimorphism of Little Buntings provide insight into the evolution of the sex-differential migration of buntings in the East Asian Flyway. 展开更多
关键词 Digital photography Emberiza pusilla Little bunting Protandrous migration Sexual dichromatism Sexual dimorphism
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Mathematical Modeling of Heat Flux Distribution in Raw Cotton Stored in Bunt
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作者 Karimov Abdusamat Ismonovich Ismanov Muhammadziyo 《Engineering(科研)》 2020年第8期591-599,共9页
The scientific article examines the physical and mechanical properties of raw cotton stored in buntings in cotton palaces. Because during the storage of raw cotton in bunts, some of its properties deteriorate, some im... The scientific article examines the physical and mechanical properties of raw cotton stored in buntings in cotton palaces. Because during the storage of raw cotton in bunts, some of its properties deteriorate, some improvements. Therefore, the mathematical modeling of storage conditions of raw cotton in bunts and the physical and mechanical conditions that occur in it is of great importance. In the developed mathematical model, the main factor influencing the physical and mechanical properties of raw cotton is the change in temperature. Due to the temperature, kinetic and biological processes accumulated in the raw cotton in Bunt, it can spread over a large surface, first in a small-local state, over time with a nonlinear law. As a result, small changes in temperature lead to a qualitative change in physical properties. In determining the law of temperature distribution in the raw cotton in Bunt, Laplace’s differential equation of heat transfer was used. The differential equation of heat transfer in Laplace’s law was replaced by a system of ordinary differential equations by approximation. Conditions are solved in MAPLE-17 program by numerical method. As a result, graphs of temperature changes over time in raw cotton were obtained. In addition, the table shows the changes in density, pressure and mass of cotton, the height of the bun. As the density of the cotton raw material increases from the top layer of the bunt to the bottom layer, an increase in the temperature in it has been observed. This leads to overheating of the bottom layer of cotton and is the main reason for the deterioration of the quality of raw materials. 展开更多
关键词 Physical Mechanical Properties The bunt Parallelepiped The Mathematical Model Biological System Heat Processes Temperature Coefficient Experiment The Bulk Density Volumetric Density Humidity FIGURE Coordinate Axes The Laplace Differential Equation Transfer Solution Approximate MAPLE
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基于校正光谱序列融合的小麦腥黑穗病籽粒分类方法
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作者 梁琨 宋金鹏 +3 位作者 张驰 梅秀明 陈赵越 张靖笛 《农业机械学报》 EI CAS CSCD 北大核心 2024年第5期263-272,共10页
针对小麦腥黑穗病轻度患病籽粒易与健康籽粒混淆,人工识别难度大的问题,将校正光谱序列融合技术与深度学习模型相结合,实现小麦腥黑穗病籽粒快速、精准分类。以健康、轻度患病、重度患病各300粒小麦籽粒的高光谱数据为样本,通过多元散... 针对小麦腥黑穗病轻度患病籽粒易与健康籽粒混淆,人工识别难度大的问题,将校正光谱序列融合技术与深度学习模型相结合,实现小麦腥黑穗病籽粒快速、精准分类。以健康、轻度患病、重度患病各300粒小麦籽粒的高光谱数据为样本,通过多元散射校正算法(MSC)和标准正态变换算法(SNV)对原始光谱进行预处理,并利用二维相关光谱法(2D-COS)分析SNV与MSC算法处理后的光谱之间的互补性。使用校正光谱序列融合技术将原始光谱、SNV预处理光谱与MSC预处理光谱三者进行融合得到序列融合光谱,以充分利用不同光谱预处理数据间的互补信息。最终,利用序列融合光谱数据建立基于ResNet 50算法的小麦腥黑病分类模型。试验结果表明,序列融合光谱ResNet 50模型总体准确率最高为93.89%,F1值为93.87%,分类性能优于单一预处理光谱建立的ResNet 50模型。为进一步评估模型分类效果,使用序列融合光谱分别建立偏最小二乘判别分析(PLS-DA)、支持向量机(SVM)以及集成学习算法模型随机森林(RF)与极端梯度提升树(XGBoost)模型,并进行对比,结果显示:SVM、PLS-DA、RF与XGBoost总体准确率分别为81.67%、84.44%、89.44%与90.55%,F1值分别为81.59%、84.04%、89.49%与90.59%,ResNet 50总体准确率与F1值优于传统光谱分析模型。因此,本研究表明校正光谱序列融合技术结合深度学习模型,能够实现对不同患病程度腥黑穗病籽粒的有效分类。 展开更多
关键词 小麦腥黑穗病 籽粒分类 校正光谱序列融合 二维相关光谱法 深度学习
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Control pattern of vocal center for vocalization in ruddy bunting(Emberiza rutila) 被引量:1
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作者 赵静 蒋锦昌 李东风 《Science China(Life Sciences)》 SCIE CAS 2003年第6期615-622,共8页
High vocal center (HVC) can produce single sound with one or two syllables by the sin-gle-type vocal control pattern in songbirds ruddy bunting (Emberiza rutila). It obviously shows left-side dominance in controlling ... High vocal center (HVC) can produce single sound with one or two syllables by the sin-gle-type vocal control pattern in songbirds ruddy bunting (Emberiza rutila). It obviously shows left-side dominance in controlling double syllables, principal frequency (PF) and increasing sound intensity of the evoked calls. Meanwhile, the complex-type control pattern can produce complex calls with multisyllable, and also shows significant left-side dominance in controlling the number of syllables, tone changing and sound intensity. These indicate that left-side HVC controls higher frequency and complicated sentence structure. The basic vocal center, dorsomedial nucleus of the intercollicular complex (DM), controls the monosyllable sound in songbirds, and shows left-side dominance in controlling both the number of syllable and sound intensity. These results not only provide some direct evidence for left-side dominance in high vocal center, but also indicate that there is some internal connection between the high and basic vocal centers in songbirds. 展开更多
关键词 ruddy bunting high VOCAL center basic VOCAL center control pattern left-side dominance.
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瑶药岩黄连种子保存技术研究
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作者 李翠 雷明 +3 位作者 陈晓英 郭晓云 张占江 韦莹 《种子》 北大核心 2023年第1期152-156,共5页
为了更好地保护珍稀濒危药用植物岩黄连,实现其资源可持续开发利用,本研究以瑶药岩黄连成熟种子为试验材料,探讨含水量、温度、保存方式等对种子保存的影响。从温度、含水量、保存方式、冷冻保护液等处理开展对瑶药岩黄连种子保存影响研... 为了更好地保护珍稀濒危药用植物岩黄连,实现其资源可持续开发利用,本研究以瑶药岩黄连成熟种子为试验材料,探讨含水量、温度、保存方式等对种子保存的影响。从温度、含水量、保存方式、冷冻保护液等处理开展对瑶药岩黄连种子保存影响研究,以单因素试验法、不同梯度法,通过数据显著性比较和结果分析,探寻岩黄连种子保存萌发活力测定的最佳条件。结果表明,当岩黄连种子含水量由26.8%降至3.6%时,其萌发率达到最高,为43.3%,最适萌发温度为25℃。超低温保存能促进岩黄连种子的萌发,保护液超低温保存法为其最佳保存方式。 展开更多
关键词 种子 萌发率 岩黄连 含水量
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基于深度学习与可见-近红外光谱的患腥黑穗病小麦籽粒分类研究 被引量:3
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作者 宋金鹏 梁琨 +3 位作者 张驰 梅秀明 蒋鹏飞 袁锐 《分析测试学报》 CAS CSCD 北大核心 2023年第7期784-793,共10页
针对小麦腥黑穗病快速无损的检测需求,该文将可见-近红外光谱与深度学习算法结合建立了小麦腥黑穗病籽粒的分类模型。采用多元散射校正算法(MSC)和标准正态变换算法(SNV)对光谱进行预处理,消除光谱噪音的影响,分别使用竞争性自适应重加... 针对小麦腥黑穗病快速无损的检测需求,该文将可见-近红外光谱与深度学习算法结合建立了小麦腥黑穗病籽粒的分类模型。采用多元散射校正算法(MSC)和标准正态变换算法(SNV)对光谱进行预处理,消除光谱噪音的影响,分别使用竞争性自适应重加权算法(CARS)和随机蛙跳算法(RF)对预处理后的光谱进行特征波长提取。结果显示,特征提取算法可去除大量冗余信息,波段减少比率为93.7%~94.2%,有效降低了模型运行成本,并可防止模型过拟合。结果显示:MSC+CARS+VGG16模型训练集的准确率为96.39%,测试集准确率为91.67%,取得了较好的分类结果。最终建立的VGG16深度学习模型实现了健康、轻度患病和重度患病3类小麦籽粒的分类。对比传统机器学习模型,VGG16模型能够充分提取光谱特征信息,更好地区分健康与轻度患病籽粒。该研究表明深度学习结合可见-近红外光谱方法,能够实现对不同患病程度腥黑穗病小麦籽粒的有效分类,为腥黑穗病小麦籽粒的快速无损检测提供了一种新方法。 展开更多
关键词 可见-近红外光谱 深度学习 腥黑穗病 小麦
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岩黄连总生物碱抑制M2型巨噬细胞抗小鼠肝癌实验研究 被引量:1
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作者 苏倩 陈好然 +3 位作者 陆洁 黄丽贞 梁健钦 张文涛 《中药材》 CAS 北大核心 2023年第7期1760-1765,共6页
目的:探讨岩黄连总生物碱能否通过负调控PI3K/AKT/mTOR信号通路抑制M2型巨噬细胞发挥抗小鼠H_(22)肝癌细胞实体瘤生长的作用。方法:建立小鼠H_(22)肝癌细胞实体瘤模型,岩黄连总生物碱高、中、低剂量(100、50、25 mg/kg)给药10 d后,称量... 目的:探讨岩黄连总生物碱能否通过负调控PI3K/AKT/mTOR信号通路抑制M2型巨噬细胞发挥抗小鼠H_(22)肝癌细胞实体瘤生长的作用。方法:建立小鼠H_(22)肝癌细胞实体瘤模型,岩黄连总生物碱高、中、低剂量(100、50、25 mg/kg)给药10 d后,称量瘤体及脾脏、胸腺质量,计算脏器系数,HE染色观察肿瘤组织病理学改变,RT-qPCR检测瘤组织M2型巨噬细胞标志物CD206 mRNA表达。体外培养RAW264.7细胞,用IL-4、IL-13(20 ng/mL)诱导细胞M2极化,岩黄连总生物碱高、中、低浓度(25、12.5、6.25μg/mL)干预24 h,流式细胞仪检测CD206阳性表达;RT-qPCR检测CD206、ARG-1、IL-10 mRNA表达;Western Blot检测RAW264.7细胞内PI3Kp110、p-AKT、p-mTOR蛋白表达。结果:动物实验结果显示,岩黄连总生物碱高、中剂量H_(22)肝癌细胞实体瘤的生长受到抑制,脾脏系数与胸腺系数显著升高(P<0.05),HE染色切片中肿瘤细胞浸润数减少,区域坏死肿瘤组织中CD206 mRNA表达显著降低(P<0.05或P<0.01)。细胞实验结果显示,岩黄连总生物碱高、中浓度组M2型巨噬细胞标志物CD206阳性表达及CD206、ARG-1、IL-10 mRNA和通路PI3Kp110、p-AKT、p-mTOR蛋白表达显著降低(P<0.05或P<0.01)。结论:岩黄连总生物碱可通过负调控PI3K/AKT/mTOR信号通路抑制巨噬细胞M2型极化发挥抗小鼠H_(22)肝癌细胞实体瘤生长作用。 展开更多
关键词 岩黄连总生物碱 肝癌 M2型巨噬细胞 PI3K/AKT/mTOR信号通路
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郭予元院士在宁夏植保防控事业中的学术贡献——纪念郭予元院士诞辰90周年
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作者 魏纪珍 陈豪 梁革梅 《植物保护》 CAS CSCD 北大核心 2023年第1期2-5,共4页
五六十年代的宁夏,农业发展落后,农业科学发展刚刚起步,引黄灌区的水稻和南部西海固地区的冬小麦分别是当地的主要粮食作物,其产量直接关乎当地群众温饱。但是由于特殊的地理位置和气候特点,这些地区病虫害发生严重,制约了当地的粮食生... 五六十年代的宁夏,农业发展落后,农业科学发展刚刚起步,引黄灌区的水稻和南部西海固地区的冬小麦分别是当地的主要粮食作物,其产量直接关乎当地群众温饱。但是由于特殊的地理位置和气候特点,这些地区病虫害发生严重,制约了当地的粮食生产。本文回顾了郭予元院士在宁夏进行病虫害科学研究,为水稻稻瘟病、小麦麦种蝇和小麦腥黑穗病的监测预警,防治示范做出的突出贡献。郭予元院士建立的预测预报体系及防治技术示范一直指导当地的农业生产,并给全国的病虫害防治做了示范。 展开更多
关键词 郭予元 稻瘟病 麦种蝇 麦腥黑穗病 技术规范
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岩黄连总生物碱对四氯化碳诱导肝纤维化大鼠的改善作用研究
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作者 覃妮 黄曙院 +5 位作者 周柳 黄华萍 沈新辉 周琳 孙东琪 陆世银 《湖南中医药大学学报》 CAS 2023年第12期2191-2198,共8页
目的研究岩黄连总生物碱对四氯化碳(carbon tetrachloride,CCl4)诱导的肝纤维化大鼠的保护作用及机制。方法通过向SD大鼠腹腔给予30%CCl4橄榄油溶液(0.1 mL/100 g)诱导复制肝纤维化模型,2次/周,连续12周。将肝纤维化大鼠随机分为模型组... 目的研究岩黄连总生物碱对四氯化碳(carbon tetrachloride,CCl4)诱导的肝纤维化大鼠的保护作用及机制。方法通过向SD大鼠腹腔给予30%CCl4橄榄油溶液(0.1 mL/100 g)诱导复制肝纤维化模型,2次/周,连续12周。将肝纤维化大鼠随机分为模型组,岩黄连总生物碱低、中、高剂量(25、50、100 mg/kg)组及联苯双酯(30 mg/kg)组,另设正常组大鼠,各组均为8只。各给药组于造模第11周按设定剂量灌胃相应药物(1.0 mL/100 g)干预,1次/d,连续2周。正常组与模型组大鼠每天灌胃等体积的生理盐水。末次给药24 h后,收集大鼠血清、肝脏及脾脏组织,测定大鼠肝脾指数;采用HE染色和Masson染色观察肝组织病理学变化。比色法检测各组血清丙氨酸转氨酶(alanine aminotransferase,ALT)、天冬氨酸转氨酶(aspartate aminotransferase,AST)、总蛋白(total protein,TP)、白蛋白(albumin,ALB)、丙二醛(malondialdehyde,MDA)、超氧化物歧化酶(superoxide dismutase,SOD)与谷胱甘肽过氧化物酶(Glutathione peroxidase,GSH-Px)的含量;通过ELISA检测血清透明质酸(hyaluronic acid,HA)、层粘连蛋白(laminin,LN)、Ⅲ型前胶原(typeⅢprocollagen,PCⅢ)及Ⅳ型胶原(collagenⅣ,Ⅳ-C)、转化生长因子-β1(transforming growth factor-β1,TGF-β1)、白细胞介素-1β(interleukin-1β,IL-1β)、白细胞介素-8(interleukin-8,IL-8)及白细胞介素-6(interleukin-6,IL-6)表达水平。结果与正常组相比,模型组大鼠反应迟钝,肝脾指数增大(P<0.01),肝组织呈现明显纤维化,血清ALT、AST、MDA、LN、HA、PCⅢ和Ⅳ-C水平显著升高(P<0.01),血清TP、ALB、SOD及GSH-Px水平显著下降(P<0.01);血清中TGF-β1、IL-1β、IL-8及IL-6蛋白表达水平显著上调(P<0.01)。与模型组比较,岩黄连总生物碱中、高剂量组均能明显改善大鼠状态和肝脾指数(P<0.05,P<0.01),有效调节大鼠肝组织病理学损伤和纤维增生;显著降低大鼠血清ALT、AST、MDA含量(P<0.01),明显提高血清TP、ALB、SOD及GSH-Px的表达水平(P<0.05,P<0.01);并能明显下调LN、HA、PCⅢ、Ⅳ-C、TGF-β1、IL-1β、IL-8及IL-6蛋白的表达水平(P<0.05,P<0.01)。结论岩黄连总生物碱具有明显的抗肝纤维化作用,其作用机制可能与抗氧化、抑制炎症因子表达相关。 展开更多
关键词 岩黄连 总生物碱 四氯化碳 肝纤维化 抗氧化 炎症因子
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1,3-二硫环已烷系列衍生物的合成及表征 被引量:8
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作者 胡卫兵 刘红霞 +1 位作者 余爱农 陈雄波 《应用化学》 CAS CSCD 北大核心 2005年第3期340-342,共3页
Seven derivatives of 1,3-dithiocyclohexane were prepared via the reaction o f 7 aldehydes(or ketones) with Bunte′s salt prepared from 1,3-dichloroprop ane and sodium thiosulfate. The procedure has the feature of easi... Seven derivatives of 1,3-dithiocyclohexane were prepared via the reaction o f 7 aldehydes(or ketones) with Bunte′s salt prepared from 1,3-dichloroprop ane and sodium thiosulfate. The procedure has the feature of easier operation, s horter reaction time and higher yield. The yields of seven derivatives of 1,3- dithiocyclohexane are between 58% and 75%. The optimum molar ratio of 1,3-d ichloropropane to sodium thiosulfate was 1∶1 in the preparati on of Bunte′s salt. The structures of seven derivatives were characterized by m eans of IR, 1H NMR, MS. 展开更多
关键词 bunteSalt法 合成 二硫环己烷 香料 表征
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