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Evolution of the Madrean-Tethyan disjunctions and the North and South American amphitropical disjunctions in plants 被引量:14
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作者 jun wen Stefanie M. ICKERT-BOND 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第5期331-348,共18页
The present paper reviews advances in the study of two major intercontinental disjunct biogeographic patterns: (i) between Eurasian and western North American deserts with the Mediterranean climate (the Madrean- T... The present paper reviews advances in the study of two major intercontinental disjunct biogeographic patterns: (i) between Eurasian and western North American deserts with the Mediterranean climate (the Madrean- Tethyan disjunctions); and (ii) between the temperate regions of North and South America (the amphitropical disjunctions). Both disjunct patterns have multiple times of origin. The amphitropical disjunctions have largely resulted from long-distance dispersal, primarily from the Miocene to the Holocene, with available data indicating that most lineages dispersed from North to South America. Results of recent studies on the Mediterranean disjuncts between the deserts of Eurasia and western North America support the multiple modes of origin and are mostly consistent with hypotheses of long-distance dispersal and the North Atlantic migration. Axelrod's Madrean-Tethyan hypothesis, which implies vicariance between the two regions in the early Tertiary, has been favored by a few studies. The Beringian migration corridor for semiarid taxa is also supported in some cases. 展开更多
关键词 amphitropical disjunctions BIOGEOGRAPHY Madrean-Tethyan disjunctions Mediterranean disjuncts North-South American disjunctions.
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Phylogenetic analysis of Toxicodendron(Anacardiaceae) and its biogeographic implications on the evolution of north temperate and tropical intercontinental disjunctions 被引量:6
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作者 Ze-Long NIE Hang SUN +1 位作者 Ying MENG jun wen 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第5期416-430,共15页
Toxicodendron is a genus in the Rhus complex of Anacardiaceae with a disjunct distribution between eastern Asia and North America, extending to southeastern Asia and the neotropics. Nuclear (internal transcribed spac... Toxicodendron is a genus in the Rhus complex of Anacardiaceae with a disjunct distribution between eastern Asia and North America, extending to southeastern Asia and the neotropics. Nuclear (internal transcribed spacer, external transcribed spacer, and NIA-i3) and chloroplast (ndhF and trnL-F) sequences were used to construct phylogenetic relationships of Toxicodendron. Phylogenetic analysis of these data strongly support Toxieodendron as a monophyletic group distinct from other genera of the Rhus complex, and the phylogeny does not fully corroborate classification at the sectional level. Two temperate disjunct lineages were detected, one from section Toxicodendron and the other between the eastern North American Toxicodendron vernix and the eastern Asian Toxicodendron vernieifluum. Their divergence times were estimated to be 13.46 (7.95-19.42) and 7.53 (2.76-12.86) mya, respectively. The disjunction between section Griffithii (taxa from warm temperate to tropical Asia) and Toxieodendron striatum (from the neotropics) was supported and their divergence time was estimated to be 20.84 (11.1 6-30.52) mya in the early Miocene. Our biogeographic results and the paleontological data support the Bering land bridge as the most likely route to explain the temperate disjunctions, yet the tropical disjunction in Toxicodendron seems to be best explained by the North Atlantic land bridge hypothesis. 展开更多
关键词 ANACARDIACEAE biogeography DISJUNCTION eastern Asia NEOTROPICS North America PHYLOGENETICS Toxicodendron.
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Evolution of biogeographic disjunction between eastern Asia and North America in Chamaecyparis:Insights from ecological niche models 被引量:2
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作者 Ping Liu jun wen Tingshuang Yi 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第3期111-116,共6页
The disjunct distribution of plants between eastern Asia(EA) and North America(NA) is one of the most well-known biogeographic patterns. However, the formation and historical process of this pattern have been long deb... The disjunct distribution of plants between eastern Asia(EA) and North America(NA) is one of the most well-known biogeographic patterns. However, the formation and historical process of this pattern have been long debated. Chamaecyparis is a good model to test previous hypotheses about the formation of this disjunct pattern as it contains six species disjunctly distributed in EA, western North America(WNA)and eastern North America(ENA). In this study, we applied ecological niche models to test the formation of the disjunct pattern of Chamaecyparis. The model calibrated with the EA species was able to predict the distribution of eastern NA species well, but not the western NA species. Furthermore, the eastern Asian species were shown to have higher niche overlap with the eastern North American species. The EA species were also shown to share more similar habitats with ENA species than with WNA species in the genus. Chamaecyparis species in WNA experienced a significant niche shift compared with congeneric species. Chamaecyparis had a low number of suitable regions in Europe and the middle and western NA during the Last Glacial Maximum(LGM) period, and became extinct in the former region whereas it retains residual distribution in the latter. The extirpations in western NA and Europe in response to the late Neogene and Quaternary climatic cooling and the more similar habitats between ENA and EA ultimately shaped the current intercontinental disjunct distribution of Chamaecyparis. Both current hypotheses may be also jointly applied to explain more eastern Asian and eastern North American disjunctions observed today. 展开更多
关键词 DISJUNCTION Eastern Asia North America CHAMAECYPARIS Ecological niche models MAXENT
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桦木科植物化石多样性及其在北半球的演化历史 被引量:1
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作者 吴隼 jun wen +1 位作者 孟盈 聂泽龙 《植物资源与环境学报》 CAS CSCD 北大核心 2023年第1期77-88,共12页
桦木科(Betulaceae)主要分布于北半球,具有非常丰富的化石记录,是研究北半球生物地理演化历史非常重要的代表类群。本文首次对桦木科植物化石数据进行全面的搜集和整理。结果显示:桦木科植物化石记录共有889条,主要来自桤木属(Alnus Mil... 桦木科(Betulaceae)主要分布于北半球,具有非常丰富的化石记录,是研究北半球生物地理演化历史非常重要的代表类群。本文首次对桦木科植物化石数据进行全面的搜集和整理。结果显示:桦木科植物化石记录共有889条,主要来自桤木属(Alnus Mill.)、桦木属(Betula Linn.)、鹅耳枥属(Carpinus Linn.)、榛属(Corylus Linn.)和铁木属(Ostrya Scop.)5个现存属以及拟榛属(Corylites Gardner)和古鹅耳枥属(Palaeocarpinus Crane)等12个灭绝属。桦木科植物化石主要分布于北半球的东亚、欧洲和北美洲的晚白垩世至更新世地层中。桦木科植物化石证据表明东亚中纬度地区是晚白垩世桦木科植物早期多样化的中心;古新世-始新世桦木科植物开始多样化,并在欧洲和北美洲多地扩散;到渐新世桦木科大部分灭绝属不再出现,少数类群继续扩张(如桤木属和桦木属);由于中新世气候变化与地质事件发生,该时期桦木科植物多样性达到顶峰;上新世-更新世桦木科植物化石数量与多样性急剧减少。桦木科植物的历史地理分布格局可能与北半球的地质变化、第四纪的冰川活动、古气候以及古地理的变迁紧密相连。 展开更多
关键词 桦木科 生物地理 化石 多样性 北半球
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Climate-Vegetation Coverage Interactions in the Hengduan Mountains Area, Southeastern Tibetan Plateau, and Their Downstream Effects
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作者 Congxi FANG Jinlei CHEN +4 位作者 Chaojun OUYANG Lu WANG Changfeng SUN Quan ZHANG jun wen 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期701-716,共16页
Little is known about the mechanism of climate-vegetation coverage coupled changes in the Tibetan Plateau(TP)region,which is the most climatically sensitive and ecologically fragile region with the highest terrain in ... Little is known about the mechanism of climate-vegetation coverage coupled changes in the Tibetan Plateau(TP)region,which is the most climatically sensitive and ecologically fragile region with the highest terrain in the world.This study,using multisource datasets(including satellite data and meteorological observations and reanalysis data)revealed the mutual feedback mechanisms between changes in climate(temperature and precipitation)and vegetation coverage in recent decades in the Hengduan Mountains Area(HMA)of the southeastern TP and their influences on climate in the downstream region,the Sichuan Basin(SCB).There is mutual facilitation between rising air temperature and increasing vegetation coverage in the HMA,which is most significant during winter,and then during spring,but insignificant during summer and autumn.Rising temperature significantly enhances local vegetation coverage,and vegetation greening in turn heats the atmosphere via enhancing net heat flux from the surface to the atmosphere.The atmospheric heating anomaly over the HMA thickens the atmospheric column and increases upper air pressure.The high pressure anomaly disperses downstream via the westerly flow,expands across the SCB,and eventually increases the SCB temperature.This effect lasts from winter to the following spring,which may cause the maximum increasing trend of the SCB temperature and vegetation coverage in spring.These results are helpful for estimating future trends in climate and eco-environmental variations in the HMA and SCB under warming scenarios,as well as seasonal forecasting based on the connection between the HMA eco-environment and SCB climate. 展开更多
关键词 Hengduan Mountains Area normalized difference vegetation index climate change net heat flux downstream effects
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Large Eddy Simulation of Vertical Structure and Size Density of Deep Layer Clouds
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作者 Bangjun CAO Xianyu YANG +2 位作者 jun wen Qin HU Ziyuan ZHU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1629-1642,1668-1670,共17页
In a convective scheme featuring a discretized cloud size density, the assumed lateral mixing rate is inversely proportional to the exponential coefficient of plume size. This follows a typical assumption of-1, but it... In a convective scheme featuring a discretized cloud size density, the assumed lateral mixing rate is inversely proportional to the exponential coefficient of plume size. This follows a typical assumption of-1, but it has unveiled inherent uncertainties, especially for deep layer clouds. Addressing this knowledge gap, we conducted comprehensive large eddy simulations and comparative analyses focused on terrestrial regions. Our investigation revealed that cloud formation adheres to the tenets of Bernoulli trials, illustrating power-law scaling that remains consistent regardless of the inherent deep layer cloud attributes existing between cloud size and the number of clouds. This scaling paradigm encompasses liquid, ice, and mixed phases in deep layer clouds. The exponent characterizing the interplay between cloud scale and number in the deep layer cloud, specifically for liquid, ice, or mixed-phase clouds, resembles that of shallow convection,but converges closely to zero. This convergence signifies a propensity for diminished cloud numbers and sizes within deep layer clouds. Notably, the infusion of abundant moisture and the release of latent heat by condensation within the lower atmospheric strata make substantial contributions. However, this role in ice phase formation is limited. The emergence of liquid and ice phases in deep layer clouds is facilitated by the latent heat and influenced by the wind shear inherent in the middle levels. These interrelationships hold potential applications in formulating parameterizations and post-processing model outcomes. 展开更多
关键词 deep layer cloud cloud spatial structure cloud size density large eddy simulation
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微探头超声内镜对肝硬化患者行食管静脉曲张套扎术治疗的预后价值评估 被引量:7
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作者 王春妍 文君 +6 位作者 胡东胜 张国梁 门昌君 张彦 赵黎莉 陆伟 李嘉 《中国内镜杂志》 2019年第4期6-10,共5页
目的应用微探头超声内镜(EUS)对肝硬化患者食管静脉曲张套扎术(EVL)治疗的预后评估。方法选择2015年8月-2017年8月于天津市第二人民医院住院治疗的肝硬化患者64例,均进行EVL根治术治疗。EVL根治术后,患者每半年复查胃镜及EUS,随访1年,... 目的应用微探头超声内镜(EUS)对肝硬化患者食管静脉曲张套扎术(EVL)治疗的预后评估。方法选择2015年8月-2017年8月于天津市第二人民医院住院治疗的肝硬化患者64例,均进行EVL根治术治疗。EVL根治术后,患者每半年复查胃镜及EUS,随访1年,胃镜观察有无食管静脉复发。EUS观察食管黏膜下静脉曲张及侧枝静脉的最大直径,记录其曲张程度。结果①EVL根治术后1年内,死亡2例,其余62例均完成随访。其中,复发30例,复发率48.4%(30/62);再次出现食管静脉曲张破裂出血患者4例,出血率6.5%(4/62);②与治疗前相比,EVL根治术后食管黏膜下静脉曲张中/重度例数、食管旁静脉曲张及周围静脉曲张重度例数,差异无统计学意义(P>0.05);③EVL根治术后,与食管静脉曲张未复发组相比,复发组食管黏膜下静脉曲张中/重度例数明显增多,食管旁静脉曲张及周围静脉曲张重度例数明显增多,差异有统计学意义(P=0.000)。结论应用微探头EUS随访EVL根治术患者,观察食管黏膜下静脉曲张及食管侧枝静脉的程度,对EVL术后食管静脉曲张复发有一定的预测价值。 展开更多
关键词 肝硬化 微探头超声内镜 食管静脉曲张套扎术 预后
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三元单体可控接枝聚氯乙烯纤维吸附剂的吸铀性能 被引量:5
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作者 刘德建 匙芳廷 +6 位作者 梁丹 吴昊岩 苟涵 阴金玉 文君 熊洁 胡胜 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第1期89-95,共7页
以聚氯乙烯(PVC)为基材,利用电子转移活化再生原子转移自由基聚合法(ARGET-ATRP)在PVC上引入丙烯腈(AN)、甲基丙烯酸甲酯(MMA)和二乙烯基苯(DVB),合成了具有高强度、高接枝率(1052%)的PVC-AO-MMA-DVB三元共聚吸附剂。并探究了PVC-AO-MMA... 以聚氯乙烯(PVC)为基材,利用电子转移活化再生原子转移自由基聚合法(ARGET-ATRP)在PVC上引入丙烯腈(AN)、甲基丙烯酸甲酯(MMA)和二乙烯基苯(DVB),合成了具有高强度、高接枝率(1052%)的PVC-AO-MMA-DVB三元共聚吸附剂。并探究了PVC-AO-MMA-DVB三元共聚吸附剂在不同固液比、不同p H、不同温度等实验条件下对铀酰离子U(Ⅵ)的吸附性能。结果表明,在固液比为1/2时,吸附量达到最高;偕胺肟吸附剂吸附铀酰离子的最佳p H范围为5. 0~5. 5;由动力学分析,PVC-AO-MMA-DVB三元共聚吸附剂吸附铀酰离子过程伴随着物理吸附和化学吸附,化学吸附占优。 展开更多
关键词 电子转移活化再生原子转移自由基聚合 接枝率 偕胺肟 铀酰
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Comparison of efficacy and safety of transpancreatic septotomy, needle-knife fistulotomy or both based on biliary cannulation unintentional pancreatic access and papillary morphology 被引量:11
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作者 jun wen Tao Li +2 位作者 Yi Lu Li-Ke Bie Biao Gong 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2019年第1期73-78,共6页
Background: Precut sphincterotomy has been widely performed to facilitate selective biliary access when standard cannulation attempts failed during endoscopic retrograde cholangiopancreatography(ERCP). However, scarce... Background: Precut sphincterotomy has been widely performed to facilitate selective biliary access when standard cannulation attempts failed during endoscopic retrograde cholangiopancreatography(ERCP). However, scarce data are available on different precut techniques for difficult biliary cannulation. This study aimed to evaluate the efficacy and safety of transpancreatic septotomy(TPS), needle-knife fistulotomy(NKF) or both based on the presence of unintentional pancreatic access and papillary morphology. Methods: Between March 2008 and December 2016, 157 consecutive patients undergoing precutting for an inaccessible bile duct during ERCP were identified. Precut techniques were chosen depending on repetitive inadvertent pancreatic cannulation and the papillary morphology. We retrospectively assessed the rates of cannulation success and procedure-related complications among three groups, namely TPS, NKF, and TPS followed by NKF. Results: The baseline characteristics of the three groups were comparable. The overall success rate of biliary cannulation reached 98.1%, including 111 of 113(98.2%) with TPS, 35 of 36(97.2%) with NKF and 8 of 8(100%) with NKF following TPS, without significant difference among groups. The incidences of total complications and post-ERCP pancreatitis were 9.6% and 7.6%, respectively. There was a trend towards less frequent post-ERCP pancreatitis after NKF(0%) compared with 11 cases(9.7%) after TPS and one case(12.5%) after NKF following TPS, but not significantly different( P = 0.07). No severe adverse event occurred during this study period. Conclusions: The choice of precut techniques by the presence of unintended pancreatic access and the papillary morphology brought about a high success rate without increasing risk in difficult biliary cannulation. 展开更多
关键词 Difficult BILIARY CANNULATION Endoscopic retrograde cholangiopancreatography Needle-knife FISTULOTOMY PRECUT techniques Transpancreatic septotomy
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有机氟化物的电化学合成 被引量:1
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作者 张子杭 李思哲 +2 位作者 阚立言 温俊 卞江 《大学化学》 CAS 2021年第12期193-213,共21页
有机氟化物在很多领域(尤其是药物方面)有着广泛的应用,但鉴于氟的特殊反应性,氟原子的引入一直是有机化学中的难题。而有机电化学合成作为近年来新兴的合成手段,大大拓宽了有机反应的界限,使得更多绿色简易的氟化方法被开发了出来。本... 有机氟化物在很多领域(尤其是药物方面)有着广泛的应用,但鉴于氟的特殊反应性,氟原子的引入一直是有机化学中的难题。而有机电化学合成作为近年来新兴的合成手段,大大拓宽了有机反应的界限,使得更多绿色简易的氟化方法被开发了出来。本文就将集中列举这些有机电化学方法氟化的实例,并探讨电化学方法对于氟化学这一领域可能的推动作用。 展开更多
关键词 有机电化学 氟化学 有机合成 方法学
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New evidence for the links between the local water cycle and the underground wet sand layer of a mega-dune in the Badain Jaran Desert, China 被引量:7
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作者 jun wen ZhongBo SU +5 位作者 TangTang ZHANG Hui TIAN YiJian ZENG Rong LIU Yue KANG Rogier van der VELDE 《Journal of Arid Land》 SCIE CSCD 2014年第4期371-377,共7页
Scientists and the local government have great concerns about the climate change and water resources in the Badain Jaran Desert of western China. A field study for the local water cycle of a lake-desert system was con... Scientists and the local government have great concerns about the climate change and water resources in the Badain Jaran Desert of western China. A field study for the local water cycle of a lake-desert system was conducted near the Noertu Lake in the Badain Jaran Desert from 21 June to 26 August 2008. An underground wet sand layer was observed at a depth of 20–50 cm through analysis of datasets collected during the field experiment. Measurements unveiled that the near surface air humidity increased in the nighttime. The sensible and latent heat fluxes were equivalent at a site about 50 m away from the Noertu Lake during the daytime, with mean values of 134.4 and 105.9 W/m2 respectively. The sensible heat flux was dominant at a site about 500 m away from the Noertu Lake, with a mean of 187.7 W/m2, and a mean latent heat flux of only 26.7 W/m2. There were no apparent differences for the land surface energy budget at the two sites during the night time. The latent heat flux was always negative with a mean value of –12.7 W/m2, and the sensible heat flux was either positive or negative with a mean value of 5.10 W/m2. A portion of the local precipitation was evaporated into the air and the top-layer of sand dried quickly after every rainfall event, while another portion seeped deep and was trapped by the underground wet sand layer, and supplied water for surface psammophyte growth. With an increase of air humidity and the occurrence of negative latent heat flux or water vapor condensation around the Noertu Lake during the nighttime, we postulated that the vapor was transported and condensed at the lakeward sand surface, and provided supplemental underground sand pore water. There were links between the local water cycle, underground wet sand layer, psammophyte growth and landscape evolution of the mega-dunes surrounding the lakes in the Badain Jaran Desert of western China. 展开更多
关键词 mega-dune water cycle observation wet sand layer Badain Jaran Desert
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High-grade myofibroblastic sarcoma in the liver: A case report 被引量:5
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作者 jun wen Wei Zhao +2 位作者 Chuan Li jun-Yi Shen Tian-Fu wen 《World Journal of Gastroenterology》 SCIE CAS 2017年第38期7054-7058,共5页
Only two cases of myofibroblastic sarcoma in the liver have been reported in the literature. Here, we report the case of a male patient with high-grade myofibroblastic sarcoma mimicking echinococcosis in the liver. Th... Only two cases of myofibroblastic sarcoma in the liver have been reported in the literature. Here, we report the case of a male patient with high-grade myofibroblastic sarcoma mimicking echinococcosis in the liver. The 25-year-old male patient complained of right upper quadrant swelling pain for one week and was initially diagnosed with echinococcosis. He was then scheduled for an exploratory laparotomy. During the operation, a huge mass exceeding 16 cm in diameter was found to occupy nearly the entire right trisegment of the liver, with a clear boundary and a round shape, and the mass was resected by right hepatic trisegmentectomy. Immunohistochemical staining revealed that the tumor tissue was positive for desmin, alpha-smooth muscle actin, CD56, and vimentin and negative for ALK-1, myogenin, calponin, beta-catenin, S100, and glypican-3, with a Ki-67 (MIB-1) index of approximately 20%. Based on the histological manifestations and immunohistochemical staining, a diagnosis of myofibroblastic sarcoma was established. The postoperative recovery was uneventful. There was no evidence of recurrence or metastasis through the last follow-up, 6 mo after surgery, despite a lack of postoperative chemotherapy or radiotherapy. To the best of our knowledge, the present case is the first reported case of high-grade myofibroblastic sarcoma in the liver, and it is also the first reported case in a male patient. 展开更多
关键词 Myofibroblastic sarcoma LIVER HIGH-GRADE MALE Immunohistochemical staining
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Phylogenetic inferences in Prunus (Rosaceae) using chloroplast ndhF and nuclear ribosomal ITS sequences 被引量:8
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作者 jun wen Scott T. BERGGREN +6 位作者 Chung-Hee LEE Stefanie ICKERT-BOND Ting-Shuang YI Ki-Oug YOO Lei XIE Joey SHAW Dan POTTER 《植物分类学报》 CSCD 北大核心 2008年第3期322-332,共11页
Sequences of the chloroplast ndhF gene and the nuclear ribosomal ITS regions are employed to recon-struct the phylogeny of Prunus (Rosaceae), and evaluate the classification schemes of this genus. The two data sets ar... Sequences of the chloroplast ndhF gene and the nuclear ribosomal ITS regions are employed to recon-struct the phylogeny of Prunus (Rosaceae), and evaluate the classification schemes of this genus. The two data sets are congruent in that the genera Prunus s.l. and Maddenia form a monophyletic group, with Maddenia nested within Prunus. However, the ndhF data set is incongruent with the ITS data supporting two major groups within Prunus: one consisting of subgenera Laurocerasus (including Pygeum) and Padus as well as the genus Maddenia and another of subgenera Amygdalus, Cerasus, and Prunus. The ITS data, on the other hand, support a clade composed of subgenera Amygdalus and Prunus and Prunus sect. Microcerasus in addition to a paraphyletic grade of subgenera Laurocerasus and Padus (and the genus Maddenia) taxa. In general, the subgeneric classifications of Prunus s.l. are not supported. The ITS and ndhF phylogenies differ mainly in interspecific relationships and the relative position of the Padus/Laurocerasus group. Both ITS and ndhF data sets suggest that the formerly recog-nized genus Pygeum is polyphyletic and that the distinction of the subgenera Padus and Laurocerasus is not supported. The biogeographic interactions of the temperate and tropical members in the Padus/Laurocera- sus/Maddenia alliance including Pygeum are shown to be highly dynamic and complex. 展开更多
关键词 系统发生学 叶绿体 核糖体 层序 核子
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Molecular phylogeny and inflorescence evolution of Prunus(Rosaceae)based on RAD-seq and genome skimming analyses 被引量:4
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作者 Na Su Richard G.J.Hodel +8 位作者 Xi Wang jun-Ru Wang Si-Yu Xie Chao-Xia Gui Ling Zhang Zhao-Yang Chang Liang Zhao Daniel Potter jun wen 《Plant Diversity》 SCIE CAS CSCD 2023年第4期397-408,共12页
Prunus is an economically important genus widely distributed in the temperate Northern Hemisphere.Previous studies on the genus using a variety of loci yielded conflicting phylogenetic hypotheses.Here,we generated nuc... Prunus is an economically important genus widely distributed in the temperate Northern Hemisphere.Previous studies on the genus using a variety of loci yielded conflicting phylogenetic hypotheses.Here,we generated nuclear reduced representation sequencing data and plastid genomes for 36 Prunus individuals and two outgroups.Both nuclear and plastome data recovered a well-resolved phylogeny.The species were divided into three main clades corresponding to their inflorescence types,-the racemose group,the solitary-flower group and the corymbose group-with the latter two sister to one another.Prunus was inferred to have diversified initially in the Late Cretaceous around 67.32 million years ago.The diversification of the three major clades began between the Paleocene and Miocene,suggesting that paleoclimatic events were an important driving force for Prunus diversification.Ancestral state reconstructions revealed that the most recent common ancestor of Prunus had racemose inflorescences,and the solitary-flower and corymb inflorescence types were derived by reduction of flower number and suppression of the rachis,respectively.We also tested the hybrid origin hypothesis of the racemose group proposed in previous studies.Prunus has undergone extensive hybridization events,although it is difficult to identify conclusively specific instances of hybridization when using SNP data,especially deep in the phylogeny.Our study provides well-resolved nuclear and plastid phylogenies of Prunus,reveals substantial cytonuclear discord at shallow scales,and sheds new light on inflorescence evolution in this economically important lineage. 展开更多
关键词 PRUNUS ROSACEAE RAD-Seq Chloroplast genome Hybridization Inflorescence evolution
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Long-term outcomes of endoscopic papillary balloon dilation for removal of bile duct stones in Billroth Ⅱ gastrectomy patients 被引量:6
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作者 Tao Li jun wen +2 位作者 Li-Ke Bie Yi Lu Biao Gong 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2018年第3期257-262,共6页
Background: Endoscopic papillary balloon dilation (EPBD) for common bile duct (CBD) stones removal in Billroth II gastrectomy patients is feasible. However, the long-term outcomes of this technique are notclear. ... Background: Endoscopic papillary balloon dilation (EPBD) for common bile duct (CBD) stones removal in Billroth II gastrectomy patients is feasible. However, the long-term outcomes of this technique are notclear. The aim of this study was to evaluate the procedural and long-term outcomes of EPBD for removal of CBD stones in Billroth II gastrectomy patients. 展开更多
关键词 Endoscopic retrograde CHOLANGIOPANCREATOGRAPHY Endoscopic papillary balloon dilation Common bile duct stonesBillroth II gastrectomy
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体外培养乳牙牙髓干细胞向血管内皮细胞定向分化的实验研究 被引量:6
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作者 刘琼 文军 +1 位作者 吴小明 钱虹 《中国现代医学杂志》 CAS 2019年第1期29-34,共6页
目的研究体外培养乳牙牙髓干细胞向血管内皮细胞的定向分化。方法选取南方医科大学口腔医院29例健康儿童的滞留乳牙,在4 h内进行乳牙牙髓干细胞的原代提取。采用免疫磁珠分选法进行细胞分选,并对分选出的细胞进行特定的血管内皮细胞定... 目的研究体外培养乳牙牙髓干细胞向血管内皮细胞的定向分化。方法选取南方医科大学口腔医院29例健康儿童的滞留乳牙,在4 h内进行乳牙牙髓干细胞的原代提取。采用免疫磁珠分选法进行细胞分选,并对分选出的细胞进行特定的血管内皮细胞定向诱导。对乳牙牙髓干细胞及血管内皮细胞定向诱导后的细胞进行镜下形态观察、血管生成实验,以及免疫表型鉴定。结果镜下形态观察显示,经过血管内皮定向诱导的乳牙牙髓干细胞呈典型血管内皮细胞的形态特征;血管生成实验表明,经过血管内皮定向诱导的乳牙牙髓干细胞可呈现明显的血管样结构;免疫表型鉴定显示经过血管内皮定向诱导的乳牙牙髓干细胞血管内皮细胞表面抗原呈阳性。结论乳牙牙髓干细胞可定向分化为血管内皮细胞。 展开更多
关键词 干细胞 内皮细胞 细胞分化 血管生成实验 免疫表型
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Isoflavones’effects on pharmacokinetic profiles of main iridoids from Gardeniae Fructus in rats 被引量:3
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作者 Ruirui Chang Jialin Liu +5 位作者 Yusha Luo Taohong Huang Qiang Li jun wen Weidong Chen Tingting Zhou 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第6期571-580,共10页
Gardeniae Fructus(GF)and Semen Sojae Praeparatum(SSP)are both medicine food homologies and widely used in Chinese clinical prescriptions together.The research investigated the pharmacokinetics of four iridoids in norm... Gardeniae Fructus(GF)and Semen Sojae Praeparatum(SSP)are both medicine food homologies and widely used in Chinese clinical prescriptions together.The research investigated the pharmacokinetics of four iridoids in normal rats and isolfavones-fed rats,which were administered with isolfavones from SSP for 7,14,21 and 28 consecutive days.A validated LC-MS/MS method was developed for determining shanzhiside,genipin-1-gentiobioside,geniposide and their metabolite genipin in rat plasma.Plasma samples were pretreated by solid-phase extraction using paeoniflorin as the internal standard.The chromatographic separation was performed on a Waters Atlantis T3(4.6 mm×150 mm,3 mm)column using a gradient mobile phase consisting of acetonitril and water(containing 0.06%acetic acid).The mass detection was under the multiple reaction monitoring(MRM)mode via polarity switching between negative and positive ionization modes.The calibration curves exhibited good linearity(r>0.997)for all components.The lower limit of quantitation was in the range of 1 e10 ng/m L.The intra-day and inter-day precisions(RSD)at three different levels were both less than 12.2%and the accuracies(RE)ranged fromà10.1%to 16.4%.The extraction recovery of them ranged from 53.8%to 99.7%.Pharmacokinetic results indicated the bioavailability of three iridoid glycosides and the metabolite,genipin in normal rats was higher than that in rats exposed to isoflavones.With the longer time of administration of isoflavones,plasma concentrations of iridoids decreased,while genipin sulfate,the phase II metabolite of genposide and genipin-1-gentiobioside,appeared the rising exposure.The pharmacokinetic profiles of main iridoids from GF were altered by isoflavones. 展开更多
关键词 IRIDOIDS Gardeniae fructus ISOFLAVONES RAT PHARMACOKINETICS LC-MS/MS
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Impact of time lags on diurnal estimates of canopy transpiration and canopy conductance from sap-flow measurements of Populus cathayana in the Qinghai–Tibetan Plateau 被引量:3
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作者 Hui Wang Kangning He +4 位作者 Runjie Li Zhuping Sheng Yun Tian jun wen Bo Chang 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第3期481-490,共10页
Recently, canopy transpiration (Ec) has been often estimated by xylem sap-flow measurements. However, there is a significant time lag between sap flow measured at the base of the stem and canopy transpiration due to... Recently, canopy transpiration (Ec) has been often estimated by xylem sap-flow measurements. However, there is a significant time lag between sap flow measured at the base of the stem and canopy transpiration due to the capacitive exchange between the transpiration stream and stem water storage. Significant errors will be introduced in canopy conductance (gc) and canopy transpiration estimation if the time lag is neglected. In this study, a cross-correlation analysis was used to quantify the time lag, and the sap flowbased transpiration was measured to pararneterize Jarvistype models of gc and thus to simulate Ec of Populus cathayana using the Penman-Monteith equation. The results indicate that solar radiation (Rs) and vapor pressure deficit (VPD) are not fully coincident with sap flow and have an obvious lag effect; the sap flow lags behind Rs and precedes VPD, and there is a 1-h time shift between Eo and sap flow in the 30-min interval data set. A parameterized Jarvis-type gc model is suitable to predict P. cathayana transpiration and explains more than 80% of the variation observed in go, and the relative error was less than 25%, which shows a preferable simulation effect. The root mean square error (RMSEs) between the predicted and measured Ec were 1.91×10^-3 (with the time lag) and 3.12×10^-3cm h^-1 (without the time lag). More importantly, Ec simulation precision that incorporates time lag is improved by 6% compared to the results without the time lag, with the mean relative error (MRE) of only 8.32% and the mean absolute error (MAE) of 1.48 × 10^-3 cm h^-1. 展开更多
关键词 Canopy transpiration Model - Populuscathayana Qinghai-Tibetan Plateau Sap flow Time lags
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M2 macrophages mediate fibrotic scar formation in the early stages after cerebral ischemia in rats 被引量:2
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作者 Jia-Gui Huang Jiang-Xia Ren +9 位作者 Yue Chen Ming-Fen Tian Li Zhou jun wen Xiao-Song Song You-Lin Wu Qing-Huan Yang Pei-Ran Jiang Jia-Ni Wang Qin Yang 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第10期2208-2218,共11页
In the central nervous system, the formation of fibrotic scar after injury inhibits axon regeneration and promotes repair. However, the mechanism underlying fibrotic scar formation and regulation remains poorly unders... In the central nervous system, the formation of fibrotic scar after injury inhibits axon regeneration and promotes repair. However, the mechanism underlying fibrotic scar formation and regulation remains poorly understood. M2 macrophages regulate fibrotic scar formation after injury to the heart, lung, kidney, and central nervous system. However, it remains to be clarified whether and how M2 macrophages regulate fibrotic scar formation after cerebral ischemia injury. In this study, we found that, in a rat model of cerebral ischemia induced by middle cerebral artery occlusion/reperfusion, fibrosis and macrophage infiltration were apparent in the ischemic core in the early stage of injury(within 14 days of injury). The number of infiltrated macrophages was positively correlated with fibronectin expression. Depletion of circulating monocyte-derived macrophages attenuated fibrotic scar formation. Interleukin 4(IL4) expression was strongly enhanced in the ischemic cerebral tissues, and IL4-induced M2 macrophage polarization promoted fibrotic scar formation in the ischemic core. In addition, macrophage-conditioned medium directly promoted fibroblast proliferation and the production of extracellular matrix proteins in vitro. Further pharmacological and genetic analyses showed that sonic hedgehog secreted by M2 macrophages promoted fibrogenesis in vitro and in vivo, and that this process was mediated by secretion of the key fibrosis-associated regulatory proteins transforming growth factor beta 1 and matrix metalloproteinase 9. Furthermore, IL4-afforded functional restoration on angiogenesis, cell apoptosis, and infarct volume in the ischemic core of cerebral ischemia rats were markedly impaired by treatment with an sonic hedgehog signaling inhibitor, paralleling the extent of fibrosis. Taken together, our findings show that IL4/sonic hedgehog/transforming growth factor beta 1 signaling targeting macrophages regulates the formation of fibrotic scar and is a potential therapeutic target for ischemic stroke. 展开更多
关键词 central nervous system extracellular matrix FIBRONECTIN fibrotic scar macrophage interleukin 4 ischemic cerebral injury neurological function Sonic hedgehog transforming growth factorβ1
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Plastid phylogenomics and biogeography of the medicinal plant lineage Hyoscyameae(Solanaceae) 被引量:2
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作者 Feng-Wei Lei Ling Tong +3 位作者 Yi-Xuan Zhu Xian-Yun Mu Tie-Yao Tu jun wen 《Plant Diversity》 SCIE CAS CSCD 2021年第3期192-197,共6页
The cosmopolitan family Solanaceae,which originated and first diversified in South America,is economically important.The tribe Hyoscyameae is one of the three clades in Solanaceae that occurs outside of the New World;... The cosmopolitan family Solanaceae,which originated and first diversified in South America,is economically important.The tribe Hyoscyameae is one of the three clades in Solanaceae that occurs outside of the New World;Hyoscyameae genera are distributed mainly in Europe and Asia,and have centers of species diversity in the Qinghai-Tibet Plateau and adjacent regions.Although many phylogenetic studies have focused on Solanaceae,the phylogenetic relationships within the tribe Hyoscyameae and its biogeographic history remain obscure.In this study,we reconstructed the phylogeny of Hyoscyameae based on whole chloroplast genome data,and estimated lineage divergence times according to the newly reported fruit fossil from the Eocene Patagonia,Physalis infinemundi,the earliest known fossil of Solanaceae.We reconstructed a robust phylogeny of Hyoscyameae that reveals the berry fruit-type Atropa is sister to the six capsule-bearing genera(Hyoscyameae sensu stricto),Atropanthe is sister to the clade(Scopolia,Physochlaina,Przewalskia),and together they are sister to the robustly supported AnisoduseHyoscyamus clade.The stem age of Hyoscyameae was inferred to be in the Eocene(47.11 Ma,95%HPD:36.75e57.86 Ma),and the crown ages of Hyoscyameae sensu stricto were estimated as the early Miocene(22.52 Ma,95%HPD:15.19e30.53 Ma),which shows a close correlation with the rapid uplift of the Qinghai-Tibet Plateau at the Paleogene/Neogene boundary.Our results provide insights into the phylogenetic relationships and the history of the biogeographic diversification of the tribe Hyoscyameae,as well as plant diversification on the Qinghai-Tibet Plateau. 展开更多
关键词 BIOGEOGRAPHY Hyoscyameae Plastid phylogenomics Qinghai-Tibet Plateau Rapid radiation SOLANACEAE
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