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鱼类的胚胎干细胞(英文) 被引量:6
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作者 洪云汉 桂建芳 +2 位作者 陈松林 邓娇蓉 Manfred SCHARTL 《动物学报》 SCIE CAS CSCD 北大核心 2003年第3期281-294,共14页
胚胎干细胞 (ES)是未分化的细胞培养物 ,来自动物的早期胚胎。它们能成为稳定的细胞系和长期冻存。在适当的条件下 ,ES细胞能分化成各种细胞类型 ,包括生殖细胞。这样 ,ES细胞就提供了一个有效的纽带 ,将动物基因组的体外和体内遗传操... 胚胎干细胞 (ES)是未分化的细胞培养物 ,来自动物的早期胚胎。它们能成为稳定的细胞系和长期冻存。在适当的条件下 ,ES细胞能分化成各种细胞类型 ,包括生殖细胞。这样 ,ES细胞就提供了一个有效的纽带 ,将动物基因组的体外和体内遗传操作连系起来。ES细胞的魅力就由其在产生和分析基因敲除老鼠中显现出来。目前 ,ES细胞技术仅见之老鼠 ,因其它脊椎动物的ES细胞的培养和建系难获成功。在鱼类 ,人们已做了大量的尝试。我们以青 (Oryziaslatipes)作为建立鱼类ES细胞技术的模式 ,通过建立并应用无滋养层细胞的培养条件 ,获得了来自中期囊胚的ES细胞系。青的ES细胞和老鼠的ES细胞有很多共同特征 ,如二倍体核型、分化潜力和形成嵌合体。因此 ,在鱼类建立和应用ES细胞技术是可能的。青ES细胞的培养条件已成功地应用到其它鱼类如斑马鱼甚至海水鱼。本文旨在以青为模式 ,综述获得和应用模式鱼和经济鱼ES细胞的主要进展和前景 [动物学报 49( 3) :2 81~ 2 94,2 0 0 3]。 展开更多
关键词 鱼类 胚胎干细胞 细胞分化 细胞培养 动物克隆 基因打靶
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鲢生长激素cDNA表达载体构建及在大肠杆菌中的表达
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作者 陈松林 Y.Hong M.Schartl 《水产学报》 CAS CSCD 北大核心 2002年第3期201-205,共5页
应用RT—PCR技术从白鲢垂体mRNA中扩增出GH全长cDNA片段 ,长度 1.2kb。将 1.2kb白鲢GHcDNA克隆到载体质粒pBluescriptKSII +(pBSKSII +)中 ,构建了pBS -scGHcDNA克隆 ;通过含有NdeI酶切位点的特异引物扩增出不含信号肽序列的cDNA片段 ,... 应用RT—PCR技术从白鲢垂体mRNA中扩增出GH全长cDNA片段 ,长度 1.2kb。将 1.2kb白鲢GHcDNA克隆到载体质粒pBluescriptKSII +(pBSKSII +)中 ,构建了pBS -scGHcDNA克隆 ;通过含有NdeI酶切位点的特异引物扩增出不含信号肽序列的cDNA片段 ,将其重组到pRSET5b载体质粒中 ,构建了白鲢GHcDNA表达质粒pRSET -scGH。将此表达质粒转化BL2 1(DE3)大肠杆菌 ,经IPTG诱导后 ,在转化的大肠杆菌中检测到GH蛋白的存在。Western印迹表明该蛋白带与草鱼GH单克隆抗体具有强烈的免疫反应。 展开更多
关键词 生长激素 CDNA 表达载体 大肠杆菌
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Antioxidants,inflammation and cardiovascular disease 被引量:30
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作者 Harald Mangge Kathrin Becker +1 位作者 Dietmar Fuchs Johanna M Gostner 《World Journal of Cardiology》 CAS 2014年第6期462-477,共16页
Multiple factors are involved in the etiology of cardiovascular disease(CVD). Pathological changes occur in a variety of cell types long before symptoms become apparent and diagnosis is made. Dysregulation of physiolo... Multiple factors are involved in the etiology of cardiovascular disease(CVD). Pathological changes occur in a variety of cell types long before symptoms become apparent and diagnosis is made. Dysregulation of physiological functions are associated with the activation of immune cells,leading to local and finally systemic inflammation that is characterized by production of high levels of reactive oxygen species(ROS). Patients suffering from inflammatory diseases often present with diminished levels of antioxidants either due to insufficient dietary intake or,and even more likely,due to increased demand in situations of overwhelming ROS production by activated immune effector cells like macrophages. Antioxidants are suggested to beneficially interfere with diseases-related oxidative stress,however the interplay of endogenous and exogenous antioxidants with the overall redox system is complex. Moreover,molecular mechanisms underlying oxidative stress in CVD are not fully elucidated. Metabolic dybalances are suggested to play a major role in disease onset and progression. Several central signalingpathways involved in the regulation of immunological,metabolic and endothelial function are regulated in a redox-sensitive manner. During cellular immune response,interferon γ-dependent pathways are activated such as tryptophan breakdown by the enzyme indoleamine 2,3-dioxygenase(IDO) in monocyte-derived macrophages,fibroblasts,endothelial and epithelial cells. Neopterin,a marker of oxidative stress and immune activation is produced by GTP-cyclohydrolase Ⅰ in macrophages and dendritic cells. Nitric oxide synthase(NOS) is induced in several cell types to generate nitric oxide(NO). NO,despite its low reactivity,is a potent antioxidant involved in the regulation of the vasomotor tone and of immunomodulatory signaling pathways. NO inhibits the expression and function of IDO. Function of NOS requires the cofactor tetrahydrobiopterin(BH4),which is produced in humans primarily by fibroblasts and endothelial cells. Highly toxic peroxynitrite(ONOO-) is formed solely in the presence of superoxide anion(O2-). Neopterin and kynurenine to tryptophan ratio(Kyn/Trp),as an estimate of IDO enzyme activity,are robust markers of immune activation in vitro and in vivo. Both these diagnostic parameters are able to predict cardiovascular and overall mortality in patients at risk. Likewise,a significant association exists between increase of neopterin concentrations and Kyn/Trp ratio values and the lowering of plasma levels of vitamin-C,-E and-B. Vitamin-B deficiency is usually accompanied by increased plasma homoycsteine. Additional determination of NO metabolites,BH4 and plasma antioxidants in patients with CVD and related clinical settings can be helpful to improve the understanding of redox-regulation in health and disease and might provide a rationale for potential antioxidant therapies in CVD. 展开更多
关键词 ATHEROGENESIS Cardiovascular disease NEOPTERIN Nitric oxide TETRAHYDROBIOPTERIN TRYPTOPHAN Oxidative stress HOMOCYSTEINE VITAMINS Antioxidative therapy
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Lipid transport to avian oocytes and to the developing embryo 被引量:7
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作者 Wolfgang J.Schneider 《The Journal of Biomedical Research》 CAS CSCD 2016年第3期174-180,共7页
Studies of receptor-mediated lipoprotein metabolic pathways in avian species have revealed that physiological intricacies of specific cell types are highly analogous to those in mammals. A prime example for the power ... Studies of receptor-mediated lipoprotein metabolic pathways in avian species have revealed that physiological intricacies of specific cell types are highly analogous to those in mammals. A prime example for the power of com- parative studies across different animal kingdoms, elucidated in the chicken, is that the expression of different lipo- protein receptors in somatic cells and oocytes are the key to oocyte growth. In avian species, yolk precursor transport from the hen's liver to rapidly growing oocytes and the subsequent transfer of yolk nutrients via the yolk sac to the developing embryo are highly efficient processes. Oocytes grow from a diameter of 5 mm to 2.5-3 cm in only 7 days, and the yolk sac transfers nutrients from the yolk stored in the mature oocyte to the embryo within just 2 weeks. The underlying key transport mechanism is receptor-mediated endocytosis of macromolecules, i.e., of hepatically synthesized yolk precursors for oocyte growth, and of mature yolk components for embryo nutrition, respectively. Recently, the receptors involved, as well as the role of lipoprotein synthesis in the yolk sac have been identified. As outlined here, lipoprotein degradation/resynthesis cycles and the expression of lipoprotein receptors are not only coordinated with the establishment of the tbllicular architecture embedding the oocyte, but also with the generation of the yolk sac vasculature essential for nutrient transfer to the embryo. 展开更多
关键词 chicken embryo OOCYTE yolk sac lipoprotein receptors VASCULARIZATION
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Seasonal variations of acute appendicitis and nonspecific abdominal pain in Finland 被引量:7
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作者 Imre Ilves Anne Fagerstrm +3 位作者 Karl-Heinz Herzig Petri Juvonen Pekka Miettinen Hannu Paajanen 《World Journal of Gastroenterology》 SCIE CAS 2014年第14期4037-4042,共6页
AIM: To investigate whether seasonal changes had an effect on the incidence of acute appendicitis (AA) or nonspecific abdominal pain (NSAP).
关键词 Acute appendicitis APPENDECTOMY Nonspecific abdominal pain INCIDENCE SEASONAL Temperature Humidity
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多球果型马尾松的形态和生殖生物学特征研究 被引量:11
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作者 王孜昌 Gerd hause +5 位作者 邓伦秀 王宏艳 刘开跃 任志得 江艺 徐涵 《种子》 CSCD 北大核心 2004年第7期30-39,42,共11页
本文对多球果型马尾松和常见型马尾松在生长状态、形态结构、生殖发育等方面的差异进行研究和分析。在多球果型马尾松雌性生殖枝上 ,能够着生 4 0~ 80个球果 (大孢子叶球 ) ,有的甚至可以达到 1 93个以上。而在常见型马尾松的雌性生殖... 本文对多球果型马尾松和常见型马尾松在生长状态、形态结构、生殖发育等方面的差异进行研究和分析。在多球果型马尾松雌性生殖枝上 ,能够着生 4 0~ 80个球果 (大孢子叶球 ) ,有的甚至可以达到 1 93个以上。而在常见型马尾松的雌性生殖枝上 ,通常只着生有 1~ 8个球果 ,最常见的是着生 2~ 4个球果。多球果型马尾松和常见型马尾松在雌球花的芽组织结构和雌球花的分化过程中有着明显的差异。通过显微分析我们发现 :多球果型马尾松雌球花原基的发育在当年生过冬顶芽的下部 ,在它的上部 ,还发育有一系列的营养芽原基 (1 0列以上 )。而常见型马尾松雌球花原基的发育在当年生过冬顶芽的顶端。雌球花发育机理的不同 ,决定了多球果型马尾松球果的着生部位发生了变异。多球果型马尾松球果着生在春梢的下 (基 )部 ,常见型马尾松球果着生在春梢的顶部。多球果型马尾松与常见型马尾松球果 (大孢子叶球 )的发育过程和发育起始时间不相同。通过对 8~ 1 2月标本进行显微切片分析 ,多球果型马尾松球果的发育起始时间在当年的 8月 (过冬顶芽开始形成的同时 ) ,与小孢子叶球的发育起始时间同步。常见型马尾松球果的发育起始时间是当年的 1 1月 ,两种类型马尾松的大孢子叶球都是在次年 4月受粉 ,到第三年的 1 展开更多
关键词 多球果型马尾松 形态特征 生殖生物学特征 无性繁殖
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The myelin membrane-associated enzyme 2′,3′-cyclic nucleotide 3′-phosphodiesterase:on a highway to structure and function 被引量:2
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作者 Arne Raasakka Petri Kursula 《Neuroscience Bulletin》 SCIE CAS CSCD 2014年第6期956-966,共11页
The membrane-anchored myelin enzyme 2′,3′-cyclic nucleotide 3′-phosphodiesterase(CNPase) was discovered in the early 1960 s and has since then troubled scientists with its peculiar catalytic activity and high exp... The membrane-anchored myelin enzyme 2′,3′-cyclic nucleotide 3′-phosphodiesterase(CNPase) was discovered in the early 1960 s and has since then troubled scientists with its peculiar catalytic activity and high expression levels in the central nervous system. Despite decades of research, the actual physiological relevance of CNPase has only recently begun to unravel. In addition to a role in myelination, CNPase is also involved in local adenosine production in traumatic brain injury and possibly has a regulatory function in mitochondrial membrane permeabilization. Although research focusing on the CNPase phosphodiesterase activity has been helpful, several open questions concerning the protein function in vivo remain unanswered. This review is focused on past research on CNPase, especially in the fields of structural biology and enzymology, and outlines the current understanding regarding the biochemical and physiological significance of CNPase, providing ideas and directions for future research. 展开更多
关键词 2′ 3′-cyclic nucleotide 3′-phosphodiesterase CALMODULIN central nervous system CYTOSKELETON myelin proteins RNA
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Knockouts of RecA-Like Proteins RadC1 and RadC2 Have Distinct Responses to DNA Damage Agents in Sulfolobus islandicus 被引量:2
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作者 Peng-Juan Liang Wen-Yuan Han +4 位作者 Qi-Hong Huang Yan-Ze Li Jin-Feng Ni Qun-Xin She Yu-Long Shen 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2013年第10期533-542,共10页
RecA family recombinases play essential roles in maintaining genome integrity. A group of RecA-like proteins named RadC are present in all archaea, but their in vivo functions remain unclear. In this study, we perform... RecA family recombinases play essential roles in maintaining genome integrity. A group of RecA-like proteins named RadC are present in all archaea, but their in vivo functions remain unclear. In this study, we performed phylogenetic and genetic analysis of two RadC proteins from Sulfolobus islandicus. RadC is closer to the KaiC lineage of cyanobacteria and proteobacteria than to the lineage of the recombinases (RecA, RadA, and Rad51) and the recombinase paralogs (e.g., RadB, Rad55, and Rad51B). Using the recently- established S. islandicus genetic system, we constructed deletion and over-expression strains of radC1 and radC2. Deletion of radC1 rendered the cells more sensitive to DNA damaging agents, methyl methanesulfonate (MMS), hydroxyurea (HU), and ultraviolet (UV) radiation, than the wild type, and a AradCIAradC2 double deletion strain was more sensitive to cisplatin and MMS than the AradC1 single deletion mutant. In addition, ectopic expression of His-tagged RadC 1 revealed that RadC I was co-purified with a putative structure-specific nuclease and ATPase, which is highly conserved in archaea. Our results indicate that both RadCI and RadC2 are involved in DNA repair. RadCl may play a general or primary role in DNA repair, while RadC2 plays a role in DNA repair in response to specific DNA damages. 展开更多
关键词 RecA-like protein RADA RadC SULFOLOBUS DNA repair
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Transient expression of the <i>Arabidopsis thaliana</i>callose synthase PMR4 increases penetration resistance to powdery mildew in barley 被引量:4
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作者 Antje Blümke Shauna C. Somerville Christian A. Voigt 《Advances in Bioscience and Biotechnology》 2013年第8期810-813,共4页
Localized cell wall thickenings, so called papillae, are a common plant defense response to fungal attack at sites of penetration of the plant cell. The major constituent of papillae is callose, a (1,3)-β-glucan poly... Localized cell wall thickenings, so called papillae, are a common plant defense response to fungal attack at sites of penetration of the plant cell. The major constituent of papillae is callose, a (1,3)-β-glucan polymer, which contributes to slowing or blocking the invading fungal hyphae. In the model plant Arabidopsis thaliana, we could recently show that the overexpression of PMR4(POWDERY MILDEW RESITANT 4), which encodes a stress induced callose synthase, results in complete powdery mildew resistance. To evaluate if these findings are also transferable to monocot crops, we transiently expressed PMR4 under control of the 35S promoter in leaves of barley (Hordeum vulgare) seedlings, which were subsequently inoculated with the virulent powdery mildew Blumeria graminis f. sp. hordei. Fusion of the green fluorescent protein (GFP) to PMR4 allowed the identification of successfully transformed barley cells, which showed an increased penetration resistance to B. graminis compared to control cells that express only GFP.PMR4-GFP localized in a similar pattern at the site of attempted fungal penetration as observed inA. thaliana, which suggests that similar transport mechanisms of the callose synthase might exist in dicot and monocot plants. 展开更多
关键词 Biotic Stress CALLOSE Glucan Fungal Resistance PLANT Defense PLANT Engineering
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Grazing impact on forage quality and macronutrient content of rangelands in Qilian Mountains, NW China 被引量:2
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作者 Alina BARANOVA Jens OLDELAND +1 位作者 WANG Shun-li Udo SCHICKHOFF 《Journal of Mountain Science》 SCIE CSCD 2019年第1期43-53,共11页
An important indicator of the rangeland health, associated with land degradation, is the ability of semi-natural rangelands to provide forage of sufficient quality for livestock production. In Qilian Mountains(Gansu P... An important indicator of the rangeland health, associated with land degradation, is the ability of semi-natural rangelands to provide forage of sufficient quality for livestock production. In Qilian Mountains(Gansu Province, NW China) biomass production and forage quality are dependent on the seasonality of precipitation and temperature; most of the precipitation falls during summer season, when sheep, goats and yaks graze mountain rangelands. To sustain the rangelands and to improve the management strategies, the assessment of the forage quality should be implemented. The purpose of this research was to study the response of biomass, forage quality and macronutrient content different levels of grazing intensity in Qilian rangelands. We sampled aboveground biomass in the growing seasons in 2012 and 2013 within spring/autumn or summer grazing regimes in two altitudinal zones below and above 3000 m a.s.l.(montane-subalpine and subalpine-alpine respectively). In order to estimate forage quality, biomass was sampled in 1 m × 1 m plots, assigned to the center of 10 ×10 m sites, fromwhich we collected different indicator parameters of rangeland health. Mineral and fiber content of forage biomass was estimated under different levels of grazing intensity with regard to the growing period. It was found that an increase in grazing intensity led to a decrease in dry matter weight. No linearity was observed in the relationship between nutritive value and grazing intensity. The highest fiber content(59.20 %) was found in plots mostly disturbed by grazing. The highest protein(16.30 %) and the lowest fiber(51.30 %) contents were associated with slightly grazing intensity. Concentrations of the mineral elements, such as Zn, P, K and S varied significantly and showed maximum values under low grazing intensity. 展开更多
关键词 Grazing intensity Nutritive value FORAGE quality Mineral concentrations Alpine Subalpine PASTURES
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Proteomic analysis of the dorsal spinal cord in the mouse model of spared nerve injury-induced neuropathic pain 被引量:3
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作者 Eun-sung Park Jung-mo Ahn +4 位作者 Sang-min Jeon Hee-jung Cho Ki-myung Chung Je-yoel Cho Dong-ho Youn 《The Journal of Biomedical Research》 CAS CSCD 2017年第6期494-502,共9页
Peripheral nerve injury often causes neuropathic pain and is associated with changes in the expression of numerous proteins in the dorsal horn of the spinal cord. To date, proteomic analysis method has been used to si... Peripheral nerve injury often causes neuropathic pain and is associated with changes in the expression of numerous proteins in the dorsal horn of the spinal cord. To date, proteomic analysis method has been used to simultaneously analyze hundreds or thousands of proteins differentially expressed in the dorsal horn of the spinal cord in rats or dorsal root ganglion of rats with certain type of peripheral nerve injury. However, a proteomic study using a mouse model of neuropathic pain could be attempted because of abundant protein database and the availability of transgenic mice. In this study, whole proteins were extracted from the ipsilateral dorsal half of the 4th-6th lumbar spinal cord in a mouse model of spared nerve injury(SNI)-induced neuropathic pain. In-gel digests of the proteins size-separated on a polyacrylamide gel were subjected to reverse-phase liquid-chromatography coupled with electrospray ionization ion trap tandem mass spectrometry(MS/MS). After identifying proteins, the data were analyzed with subtractive proteomics using ProtAn, an in-house analytic program. Consequently, 15 downregulated and 35 upregulated proteins were identified in SNI mice. The identified proteins may contribute to the maintenance of neuropathic pain,and may provide new or valuable information in the discovery of new therapeutic targets for neuropathic pain. 展开更多
关键词 PROTEOMICS spinal dorsal horn neuropathic pain spared nerve injury MOUSE
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Technical and conceptual considerations forusing animated stimuli in studies of animalbehavior 被引量:11
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作者 Laura CHOUINARD-THULY Stefanie GIERSZEWSKI +10 位作者 Gil G. ROSENTHAL Simon M. READER Guillaume RIEUCAU Kevin L. Woo Robert GERLAI Cynthia TEDORE Spencer J. INGLEY John R. STOWERS Joachim G.FROMMENI Francine L. DOLINS Klaudia WITTE 《Current Zoology》 SCIE CAS CSCD 2017年第1期5-19,共15页
Rapid technical advances in the field of computeropened new avenues in animal behavior research.animation (CA) and virtual reality (VR) haveAnimated stimuli are powerful tools as theyoffer standardization, repeata... Rapid technical advances in the field of computeropened new avenues in animal behavior research.animation (CA) and virtual reality (VR) haveAnimated stimuli are powerful tools as theyoffer standardization, repeatability, and complete control over the stimulus presented, thereby"reducing" and "replacing" the animals used, and "refining" the experimental design in line withthe 3Rs. However, appropriate use of these technologies raises conceptual and technical questions.In this review, we offer guidelines for common technical and conceptual considerations related tothe use of animated stimuli in animal behavior research. Following the steps required to create ananimated stimulus, we discuss (I) the creation, (11) the presentation, and (111) the validation of CAsand VRs. Although our review is geared toward computer-graphically designed stimuli, consider-ations on presentation and validation also apply to video playbacks. CA and VR allow both new be-havioral questions to be addressed and existing questions to be addressed in new ways, thus weexpect a rich future for these methods in both ultimate and proximate studies of animal behavior. 展开更多
关键词 ANIMAL behavior animated stimulus COMPUTER animation experimental design virtual reality visual communication.
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first record of sphenomorphus incognitus (thompson, 1912) (squamata:scincidae) from vietnam with some notes on natural history 被引量:3
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《Asian Herpetological Research》 SCIE 2012年第2期-,共4页
Sphenomorphus incognitus is recorded for the first time outside of China. The new locality record is from the Tay Yen Tu Nature Reserve in Bac Giang Province, northeastern Vietnam at elevations between 200–450 m. Bas... Sphenomorphus incognitus is recorded for the first time outside of China. The new locality record is from the Tay Yen Tu Nature Reserve in Bac Giang Province, northeastern Vietnam at elevations between 200–450 m. Based on the newly collected specimens, we present an expanded description and provide data on the natural history of this species in northern Vietnam. 展开更多
关键词 new record Sphenomorphus incognitus Tay Yen Tu Nature Reserve Bac Giang Province VIETNAM
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Single-cell transcriptomics reveals cell type diversity of human prostate 被引量:1
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作者 Yang Chen Peng Zhang +14 位作者 Jinling Liao Jiwen Cheng Qin Zhang Tianyu Li Haiying Zhang Yonghua Jiang Fangxing Zhang Yanyu Zeng Linjian Mo Haibiao Yan Deyun Liu Qinyun Zhang Chunlin Zou Gong-Hong Wei Zengnan Mo 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2022年第11期1002-1015,共14页
Extensive studies have been performed to describe the phenotypic changes occurring during malignant transformation of the prostate.However,the cell types and associated changes that contribute to the development of pr... Extensive studies have been performed to describe the phenotypic changes occurring during malignant transformation of the prostate.However,the cell types and associated changes that contribute to the development of prostate diseases and cancer remain elusive,largely due to the heterogeneous composition of prostatic tissues.Here,we conduct a comprehensive evaluation of four human prostate tissues by singlecell RNA sequencing(sc RNA-seq)to analyze their cellular compositions.We identify 18 clusters of cell types,each with distinct gene expression profiles and unique features;of these,one cluster of epithelial cells(Ep)is found to be associated with immune function.In addition,we characterize a special cluster of fibroblasts and aberrant signaling changes associated with prostate cancer(PCa).Moreover,we provide insights into the epithelial changes that occur during the cellular senescence and aging.These results expand our understanding of the unique functional associations between the diverse prostatic cell types and the contributions of specific cell clusters to the malignant transformation of prostate tissues and PCa development. 展开更多
关键词 scRNA-seq Human prostate Cell type diversity IMMUNITY Cellular senescence Prostate cancer
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预治疗患儿血中氢化可的松浓度可预测支气管肺发育不良高危婴儿对预防性应用皮质醇的反应 被引量:2
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作者 Peltoniemi O. Kari M.A. +2 位作者 Heinonen K. M. Hallman 李丹 《世界核心医学期刊文摘(儿科学分册)》 2005年第10期55-55,共1页
Objectives: To investigate the effect of hydrocortisone treatment on survival without bronchopulmonary dysplasia (BPD) and to study whether serum cortisol con centrations predict the response. Study design: We perform... Objectives: To investigate the effect of hydrocortisone treatment on survival without bronchopulmonary dysplasia (BPD) and to study whether serum cortisol con centrations predict the response. Study design: We performed a randomized, place bo-controlled trial on infants with gestation ≤30 weeks, body weight of 501 to 1250 g, and respiratory failure. Hydrocortisone was started before 36 hours of age and given for 10 days at doses from 2.0 to 0.75 mg/kg per day. Shortly befor e hydrocortisone treatment, basal and stimulated (ACTH, 0.1 μg/kg) serum cortis ols were measured. Results: The study was discontinued early, because of gastroi ntestinal perforations in the hydrocortisone group (4/25 vs 0/26, P =. 05); 3 of the 4 had received indomethacin/ibuprofen. The incidence of BPD (28%vs placebo 42%, P = 0.28) tended to be lower, and patent ductus arteriosus (36%vs 73%, P =. 01)was lower in the hydrocortisone group. The hydrocortisone-treated infan ts with serum cortisol concentrations above the median had a high risk of gastro intestinal perforation. In infants with cortisol values below the median, hydroc ortisone treatment increased survival without BPD. Conclusions: Serum cortisol c oncentrations measured shortly after birth may identify those very high-risk in fants who may benefit from hydrocortisone supplementation. 展开更多
关键词 预治疗 预防性应用 测定基础 胃肠穿孔 存活儿 对照试验 安慰剂 呼吸衰竭 随机化 消炎痛
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The Multiplicity of Heat Stress Transcription Factors Controlling the Complex Heat Stress Response of Plants
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作者 LutzNover 《Acta Genetica Sinica》 SCIE CAS CSCD 北大核心 2004年第9期1006-1007,共2页
Heat stress proteins (Hsp) and heat stress transcription factors (Hsf) are structurally and functionally conserved elements of the eukaryotic heat stress response. However, compared to other organisms, plants have muc... Heat stress proteins (Hsp) and heat stress transcription factors (Hsf) are structurally and functionally conserved elements of the eukaryotic heat stress response. However, compared to other organisms, plants have much more elaborate systems of chaperones and at least 21 transcription factors controlling their expression. 展开更多
关键词 植物 热应激 转录因子 多样性 热应激蛋白
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Metabolomic changes in fatty liver can be modified by dietary protein and calcium during energy restriction 被引量:1
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作者 Taru K Pilvi Tuulikki Seppnen-Laakso +6 位作者 Helena Simolin Piet Finckenberg Anne Huotari Karl-Heinz Herzig Riitta Korpela Matej Orei Eero M Mervaala 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第28期4462-4472,共11页
AIM: To characterise the effect of energy restriction (ER) on liver lipid and primary metabolite profile by using metabolomic approach. We also investigated whether the effect of energy restriction can be further e... AIM: To characterise the effect of energy restriction (ER) on liver lipid and primary metabolite profile by using metabolomic approach. We also investigated whether the effect of energy restriction can be further enhanced by modification of dietary protein source and calcium. METHODS: Liver metabolomic profile of lean and obese C57BI/6J mice (n = 10/group) were compared with two groups of weight-reduced mice. ER was performed on control diet and whey protein-based high-calcium diet (whey + Ca). The metabolomic analyses were performed using the UPLC/MS based lipidomic platform and the HPLC/MS/MS based primary metabolite platform.RESULTS: ER on both diets significantly reduced hepatic lipid accumulation and lipid droplet size, while only whey + Ca diet significantly decreased blood glucose (P 〈 0.001) and serum insulin (P 〈 0.01). In hepatic lipid species the biggest reduction was in the level of triacylglycerols and cerarnides while the level of cholesterol esters was significantly increased during ER. Interestingly, diacylglycerol to phospholipid ratio, an indicator of relative amount of diabetogenic diglyceride species, was increased in the control ER group, but decreased in the whey + Ca ER group (P 〈 0.001, vs obese). ER on whey + Ca diet also totally reversed the obesity induced increase in the relative level of lipotoxic cerarnides (P 〈 0.001, vs obese; P 〉 0.05, vs lean). These changes were accompanied with up-regulated TCA cycle and pentose phosphate pathway rnetabolites. CONCLUSION: ER-induced changes on hepatic rnetabolornic profile can be significantly affected by dietary protein source. The therapeutic potential of whey protein and calcium should be further studied. 展开更多
关键词 Fatty liver Metabolomics Energy restriction Whey protein Dietary calcium
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The Synaptonemal Complex of Basal Metazoan Hydra:More Similarities to Vertebrate than Invertebrate Meiosis Model Organisms
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作者 Johanna Fraune Miriam Wiesner Ricardo Benavente 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2014年第3期107-115,共9页
The synaptonemal complex (SC) is an evolutionarily well-conserved structure that mediates chromosome synapsis during prophase of the first meiotic division. Although its structure is conserved, the characterized pro... The synaptonemal complex (SC) is an evolutionarily well-conserved structure that mediates chromosome synapsis during prophase of the first meiotic division. Although its structure is conserved, the characterized protein components in the current metazoan meiosis model systems (Drosophila melanogaster, Caenorhabditis elegans, and Mus musculus) show no sequence homology, challenging the question of a single evolutionary origin of the SC. However, our recent studies revealed the monophyletic origin of the mammalian SC protein components. Many of them being ancient in Metazoa and already present in the cnidarian Hydra. Remarkably, a comparison between different model systems disclosed a great similarity between the SC components of Hydra and mammals while the proteins of the ecdysozoan systems (D. rnelanogaster and C. elegans) differ significantly. In this review, we introduce the basal-branching metazoan species Hydra as a potential novel invertebrate model system for meiosis research and particularly for the investigation of SC evolution, function and assembly. Also, available methods for SC research in Hydra are summarized. 展开更多
关键词 MEIOSIS Synaptonemal complex HYDRA Evolution
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Strain Mesorhizobium sp.CCNWGX035:A Stress-Tolerant Isolate from Glycyrrhiza glabra Displaying a Wide Host Range of Nodulation
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作者 WEI Ge-Hong YANG Xue-Ying +2 位作者 ZHANG Zhi-Xin YANG Ya-Zhen K. LINDSROM 《Pedosphere》 SCIE CAS CSCD 2008年第1期102-112,共11页
Thirty-nine rhizobial isolates were isolated from the root nodules of Glycyrrhiza uralensis and Glyeyrrhiza glabra, growing in the arid and semiarid regions of northwestern China, to test their taxonomic position and ... Thirty-nine rhizobial isolates were isolated from the root nodules of Glycyrrhiza uralensis and Glyeyrrhiza glabra, growing in the arid and semiarid regions of northwestern China, to test their taxonomic position and stress tolerance and to select one promising putative inoeulant strain for further studies. On the basis of 113 physiological and biochemical characteristics, the isolates were clustered into three groups. One isolate CCNWGX035 was found to have high tolerance to NaC1, pH, and temperature. By sequencing the 16S rDNA, isolate CCNWGX035 was placed in genus Mesorhizobium. Nodulation tests demonstrated that the isolate not only formed nitrogen-fixing nodules on its original host plant Glyeyrrhiza glabra, but also on Sophora vieiifolia, Lotus cornieulatus, Trifolium repens, Melilotus suaveolens, and Sophora alopecuroides. On the basis of sequence analysis of the nodA gene, isolate CCNWGX035 was closely related to strains of the genus Mesorhizobium, exhibiting some novel characteristics of root nodule bacteria. 展开更多
关键词 GLYCYRRHIZA host range MESORHIZOBIUM nodA stress tolerance
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多球果型马尾松形态及生殖生物学特征研究
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作者 王孜昌 Gerd hause +4 位作者 邓伦秀 王宏艳 刘开跃 任志得 徐涵 《中国造纸学报》 CAS CSCD 北大核心 2004年第z1期375-379,共5页
多球果型马尾松是马尾松种群内的一个具特异性状的变异体.在多球果型马尾松雌性生殖枝上,能够着生40~80个球果(大孢子叶球),有的甚至可以达到193个以上.而在常见型马尾松的雌性生殖枝上,通常只着生有1~8个球果,最常见的着生2-4个球果... 多球果型马尾松是马尾松种群内的一个具特异性状的变异体.在多球果型马尾松雌性生殖枝上,能够着生40~80个球果(大孢子叶球),有的甚至可以达到193个以上.而在常见型马尾松的雌性生殖枝上,通常只着生有1~8个球果,最常见的着生2-4个球果.本文对多球果型马尾松和常见型马尾松在生长状态、形态结构、生殖发育等方面的差异进行了研究和分析. 展开更多
关键词 马尾松 多球果 特征 发生机理 繁殖
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