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高中生性过把瘾就死?——校园性过错调查
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作者 星星 《福建基础教育研究》 2005年第Z2期25-28,共4页
在大多数人眼里,也许“同居”这个话题跟高中生根本搭不上什么边,认为那是大学里的专利,但是一封不同寻常的来信让记者改变了看法。“编辑部的叔叔阿姨你们好!我是一名高中生,虽然我今年只有16岁,但我在学校里却谈了一个女朋友。女朋友... 在大多数人眼里,也许“同居”这个话题跟高中生根本搭不上什么边,认为那是大学里的专利,但是一封不同寻常的来信让记者改变了看法。“编辑部的叔叔阿姨你们好!我是一名高中生,虽然我今年只有16岁,但我在学校里却谈了一个女朋友。女朋友每到周末都让我陪她一起去逛街,有一次我们玩晚了进不了校园,她就提议在外面的录像厅里包夜。 展开更多
关键词 学校 专利 性过错 中生性 医院 手术室 编辑部 性行为 调查
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原发皮肤CD4^(+)小到中等大T细胞淋巴组织增生性疾病临床病理观察
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作者 申龙树 谢玲 +3 位作者 司海鹏 王剑蓉 可飞 章宜芬 《诊断病理学杂志》 2021年第10期848-852,共5页
目的观察原发皮肤CD4+小到中等大T细胞淋巴组织增生性疾病(Primary cutaneous CD4+small/medium T-cell lymphoproliferative disorder,PCSMTCLPD)临床病理特征。方法收集3例PCSMTCLPD患者临床资料,取病变组织进行病理检查,利用HE染色... 目的观察原发皮肤CD4+小到中等大T细胞淋巴组织增生性疾病(Primary cutaneous CD4+small/medium T-cell lymphoproliferative disorder,PCSMTCLPD)临床病理特征。方法收集3例PCSMTCLPD患者临床资料,取病变组织进行病理检查,利用HE染色、免疫组化等方法明确诊断并随访,结合文献分析疾病的临床病理特点。结果2例表现为背部皮肤单发性结节,1例表现为头颈部多发性结节;光镜下见真皮内致密淋巴细胞弥漫、结节状、条带状浸润,局部浸润到皮下脂肪组织,皮肤附件内可见少量淋巴细胞浸润,并见小血管增生现象;其中异型淋巴细胞形态小到中等大,形态多样,核深染,可见小核仁;免疫组化阳性表达CD3、CD4,部分阳性表达Bcl-6、PD-1、CXCL-13,阴性表达CD10、CD8,细胞增殖活性较低,Ki-67约10~20%,诊断为PCSMTCLPD。随访10~39月,未见病变复发或进展,患者健康状况良好。结论PCSMTCLPD具有惰性临床过程,正确诊断并选择适当的治疗措施具有重要临床意义。 展开更多
关键词 原发皮肤CD4^(+)小到等大T细胞淋巴组织增生性疾病 免疫组化 外周T细胞淋巴瘤
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人体增生性疤痕中的成肌纤维细胞和细胞凋亡:干扰素α2b的作用
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作者 蔡振鑫 《国外医学(外科学分册)》 2002年第3期168-168,共1页
关键词 人体增生性疤痕 成肌纤维细胞 细胞凋亡干扰 Α2B 作用
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Integrative analysis of bone-formation associated genes and immune cell infiltration in osteoporosis, and the prediction of active ingredients in targeted traditional Chinese medicine
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作者 WANG Kai DONG Ping GUO Hongzhang 《Digital Chinese Medicine》 CAS CSCD 2024年第2期160-170,共11页
Objective To explore the differential expression and mechanisms of bone formation-related genes in osteoporosis(OP)leveraging bioinformatics and machine learning methodologies;and to predict the active ingredients of ... Objective To explore the differential expression and mechanisms of bone formation-related genes in osteoporosis(OP)leveraging bioinformatics and machine learning methodologies;and to predict the active ingredients of targeted traditional Chinese medicine(TCM)herbs.Methods The Gene Expression Omnibus(GEO)and GeneCards databases were employed to conduct a comprehensive screening of genes and disease-associated loci pertinent to the pathogenesis of OP.The R package was utilized as the analytical tool for the identification of differentially expressed genes.Least absolute shrinkage and selection operator(LASSO)logis-tic regression analysis and support vector machine-recursive feature elimination(SVM-RFE)algorithm were employed in defining the genetic signature specific to OP.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses for the selected pivotal genes were conducted.The cell-type identification by estimating rela-tive subsets of RNA transcripts(CIBERSORT)algorithm was leveraged to examine the infiltra-tion patterns of immune cells;with Spearman’s rank correlation analysis utilized to assess the relationship between the expression levels of the genes and the presence of immune cells.Coremine Medical Database was used to screen out potential TCM herbs for the treatment of OP.Comparative Toxicogenomics Database(CTD)was employed for forecasting the TCM ac-tive ingredients targeting the key genes.AutoDock Vina 1.2.2 and GROMACS 2020 softwares were employed to conclude analysis results;facilitating the exploration of binding affinity and conformational dynamics between the TCM active ingredients and their biological targets.Results Ten genes were identified by intersecting the results from the GEO and GeneCards databases.Through the application of LASSO regression and SVM-RFE algorithm;four piv-otal genes were selected:coat protein(CP);kallikrein 3(KLK3);polymeraseγ(POLG);and transient receptor potential vanilloid 4(TRPV4).GO and KEGG pathway enrichment analy-ses revealed that these trait genes were predominantly engaged in the regulation of defense response activation;maintenance of cellular metal ion balance;and the production of chemokine ligand 5.These genes were notably associated with signaling pathways such as ferroptosis;porphyrin metabolism;and base excision repair.Immune infiltration analysis showed that key genes were highly correlated with immune cells.Macrophage M0;M1;M2;and resting dendritic cell were significantly different between groups;and there were signifi-cant differences between different groups(P<0.05).The interaction counts of resveratrol;curcumin;and quercetin with KLK3 were 7;3;and 2;respectively.It shows that the interac-tions of resveratrol;curcumin;and quercetin with KLK3 were substantial.Molecular docking and molecular dynamics simulations further confirmed the robust binding affinity of these bioactive compounds to the target genes.Conclusion Pivotal genes including CP;KLK3;POLG;and TRPV4;exhibited commendable significant prognostic value;and played a crucial role in the diagnostic assessment of OP.Resveratrol;curcumin;and quercetin;natural compounds found in TCM;showed promise in their potential to effectively modulate the bone-forming gene KLK3.This study provides a sci-entific basis for the interpretation of the pathogenesis of OP and the development of clinical drugs. 展开更多
关键词 OSTEOPOROSIS Bone formation Differentially expressed genes Biological information Traditional Chinese medicine(TCM) Active ingredients Molecular mechanism
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广东内伶仃岛台湾相思群落在15年间的演替研究 被引量:7
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作者 徐华林 袁天天 +2 位作者 王蕾 关开朗 廖文波 《生态科学》 CSCD 2016年第4期12-22,共11页
针对1997—1998年在广东内伶仃岛设置并调查的5个台湾相思林固定样地,15年后于2013年再次进行调查并研究群落的演替。结果表明:(1)经过15年的演替,5个台湾相思群落的优势种群发生明显变化,少数种群消退,另又增添了部分优势种群,并且整... 针对1997—1998年在广东内伶仃岛设置并调查的5个台湾相思林固定样地,15年后于2013年再次进行调查并研究群落的演替。结果表明:(1)经过15年的演替,5个台湾相思群落的优势种群发生明显变化,少数种群消退,另又增添了部分优势种群,并且整体上以中生性树种为主;(2)在演替过程中,台湾相思群落的物种多样性指数有上升,亦有下降,但5个群落其乔木层的物种组成更加丰富,年龄结构更加复杂;(3)在5个群落中,台湾相思多以第Ⅳ、Ⅴ龄级立木存在,缺少Ⅰ、Ⅱ、Ⅲ级立木,说明其均为衰退种群。总体上,内伶仃岛的台湾相思群落在后期将演替成为以中生性树种为主的常绿阔叶林群落。 展开更多
关键词 台湾相思 群落演替 广东省内伶仃岛 中生性树种
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Estimates of Heritability and Genetic Correlations for Growth Traits in Chinese Shrimp Fenneropenaeus chinensis 被引量:2
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作者 何玉英 王清印 +3 位作者 谭乐义 李健 陈华增 李吉涛 《Agricultural Science & Technology》 CAS 2011年第4期613-616,共4页
[Objective] The aim was to estimate the heritability and genetic correlations of growth traits of Chinese shrimp Fenneropenaeus chinensis so as to provide basis and technical parameters for the breeding and selecting ... [Objective] The aim was to estimate the heritability and genetic correlations of growth traits of Chinese shrimp Fenneropenaeus chinensis so as to provide basis and technical parameters for the breeding and selecting of Chinese shrimp.[Method] 51 full-sib families(including 35 half-sib families)of the Chinese shrimp F.chinensis were obtained by artificial insemination.Four growth traits of these families were measured,including body length,cephalothorax length,abdorminal segment length and body weight.According to quantitative genetics theory,the heritability of each growth trait,genetic and phenotypic correlation among these traits was statistically studied.[Result] The heritability was 0.36-0.51 for body length,0.14-0.24 for cephalothorax length,0.25-0.50 for abdominal segment length,and 0.04-0.29 for body weight.High and positive genetic correlations were obtained among growth traits.The genetic correlation between body weight and abdominal segment length was the highest(0.92),followed by body length and abdominal segment length(0.91),body length and body weight(0.88),body weight and cephalothorax length(0.87),abdominal segment length and cephalothorax length(0.86),while the genetic correlation between body length and cephalothorax length was the lowest(0.83).[Conclusion] The phenotypic correlation of body length,cephalothorax length,abdorminal segment length and body weight of Chinese shrimp F.chinensis were from 0.80 to 0.90 with extremely significant difference(P0.01)among the four growth traits by t-test. 展开更多
关键词 Fenneropenaeus chinensis Growth traits HERITABILITY Genetic correlation
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Effects of a Self-made Compound Chinese Herbal Medicine Additive on Growth Performance and Occurrence of Diarrhea in Weaned Piglets 被引量:3
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作者 赖宝色 林秋敏 +1 位作者 林伯全 纪忠 《Agricultural Science & Technology》 CAS 2015年第2期327-329,共3页
In this study,the effects of compound Chinese herbal medicine on growth performance and occurrence of diarrhea in weaned piglets were investigated.A compound Chinese herbal medicine that consisted of Astragalus membra... In this study,the effects of compound Chinese herbal medicine on growth performance and occurrence of diarrhea in weaned piglets were investigated.A compound Chinese herbal medicine that consisted of Astragalus membranaceus,Codonopsis pilosula,Epimedium sagittatum,massa medicata fermentata,Atractylodes macrocephala,malt,Glycyrrhiza uralensis,Angelica sinensis and Crataegus pinnatifida,was crushed and then passed through a 500-mesh sieve.The obtained powder was added to the basal diet of weaned piglets.A total of 100 healthy crossbred weaned piglets,aging 26±2 days,were selected.They were randomly divided into 5groups(20 piglets/group) in according to principles of similar parity(3-5),similar body weight and half male and half female.The piglets in the control group were fed with basal diet.For the piglets in the I,II and III groups,0.4%,0.7% and 1.0%of Chinese herbal medicine additive were added to the basal diets,respectively.The basal diet of piglets in the IV group was added with 30 mg/kg of oxytetracycline.The results showed the incidences of diarrhea in I,II and III groups were4.85%,5.14% and 5.63% lower than that of control groups(P〈0.05).There was no significant difference in incidence of diarrhea between the control and the IV groups. 展开更多
关键词 Chinese herbal medicine ANTIBIOTICS Growth performance Incidence of diarrhea
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Nestedness of bird assemblages in the karst forest fragments of southwestern Guangxi, China 被引量:3
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作者 李肇天 陆舟 +3 位作者 舒晓莲 蒋光伟 许亮 周放 《Chinese Birds》 CSCD 2013年第2期170-183,共14页
The limestone region in southwestern Guangxi contains the most typical karst landforms in the world. Due to their destruction, the original forests mainly survive in nature reserves in the form of fragmented areas. Fr... The limestone region in southwestern Guangxi contains the most typical karst landforms in the world. Due to their destruction, the original forests mainly survive in nature reserves in the form of fragmented areas. From June 2009 to September 2010 we conducted an investigation of 13 relatively isolated habitats or sites, selected from each of the 13 nature reserves in southwestern Guangxi, with the least amount of anthropological activity and the largest presence of the original vegetation, in order to study the distribution of birds on forest fragments. The distribution patterns of the birds and the factors which affect them were analyzed by using the 'BINMATNEST' software and the Spearman’s rank correlation analysis, to determine: 1) whether nested patterns of birds in the karst area of southwestern Guangxi exist or not and 2) which factors are correlated with the nested patterns and the effect of these factors on forming nested patterns. The results show that the birds had statistically significant nested patterns in the karst area and the specificity of the habitat of the birds had a significant effect on the nested patterns. We suggest possible reasons for these results, based on the characteristics of the seasonal tropical rain forests in the study area and on neutral theory. We also urgently recommend that close attention be paid to the protection of the diversity of the environment for birds in all fragmented habitats. 展开更多
关键词 BIRDS NESTEDNESS habitat fragmentation karst area neutral theory
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Discovery of the Male Adult of Celaenorrhinus kiku Hering, 1918 (Lepidoptera: Hesperiidae: Pyrginae) 被引量:2
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作者 薛国喜 张雅林 袁锋 《Entomotaxonomia》 CSCD 北大核心 2009年第4期305-309,共5页
Ninety years after Celaenorrhinus kiku was reported as new to science, the male of this species was discovered and described for the first time in the present paper. Both external and genitalic characters proved it to... Ninety years after Celaenorrhinus kiku was reported as new to science, the male of this species was discovered and described for the first time in the present paper. Both external and genitalic characters proved it to be a good species. 展开更多
关键词 LEPIDOPTERA Skippers Male genitalia TAXONOMY China
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Effects of Different Padding on Air Quality in Broiler House and Growth Physiological Index of Broilers 被引量:1
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作者 刘雪兰 张燕 +5 位作者 阎佩佩 井庆川 魏祥法 刘瑞亭 石天虹 武彬 《Agricultural Science & Technology》 CAS 2015年第12期2764-2769,共6页
[Objective] This study aimed to investigate the effects of different padding on ammonia concentration in broiler house and growth performance and blood indi- cators of broilers. [Method] A total of 480 one-day-old 817... [Objective] This study aimed to investigate the effects of different padding on ammonia concentration in broiler house and growth performance and blood indi- cators of broilers. [Method] A total of 480 one-day-old 817 broilers were selected. They were randomly divided into four groups with different paddings, and each group was in triplicate. The weights of broilers and feed were weighed weekly. The growth performance of broilers was determined. On day 30, the ammonia concentra- tions in broiler houses were determined. On day 35, 6 broilers were randomly se- lected from each group, and their vein blood was sampled. In the sampled vein blood, the concentrations of ammonia, glucose, globulin, serum total protein and urea nitrogen were determined. [Result] There were significant differences in ammo- nia concentration among broiler houses laid with different paddings (P〈0.05). The ammonia concentration in group 1 was significantly lower than those in group 3 and group 4 (P〈0.05). No significant difference was found in ammonia concentrations in broiler houses between group 2 and group 3 (P〉0.05). The ammonia concentration in group 4 was significantly higher than those in group1, group 2 and group 3 (,0〈 0.05). There were also significant differences in blood indicators among different groups (P〈0.05). The blood ammonia, blood glucose and serum urea nitrogen con- centrations in group 1 were significantly lower than those in other groups (P〈0.05), the serum total protein concentration was significantly higher than those in group 3 and group 4 (P〈0.05), and the serum globulin concentration was significantly higher than those in group 2, group 3 and group 4 (P〈0.05). Significant differences were observed in feed intake, body weight gain and slaughter weight between different groups (P〈0.05), but there were no significant differences in feed to grain ratio (P〉 0.05). [Conclusion] Under the experimental conditions, the padding of Chinese medicine residue showed better effect on reducing ammonia concentration in broiler house, which was conducive to play of production potential of broilers. 展开更多
关键词 Chinese medicine residue PADDING Ammonia concentration Production performance Blood indicators
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Fifty Years of Botanical Gardens in China 被引量:10
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作者 贺善安 《Acta Botanica Sinica》 CSCD 2002年第9期1123-1133,共11页
The development, distribution and features of one hundred and forty botanical gardens (BGs) in China are reported and their functions on research, conservation, display and utilization of biodiversity are summarized i... The development, distribution and features of one hundred and forty botanical gardens (BGs) in China are reported and their functions on research, conservation, display and utilization of biodiversity are summarized in this paper. The contributions to the social and economic development in the early stage of Chinese BGs with the researches of economic plant (tobacco), medicinal plant (yam) and wild fruit tree resources are evaluated. The theoretical and applied achievements in recent years in seed science, plant conservation, economic plant introduction, acclimatization and breeding are also described. A general scope of living plant collections in Chinese BGs is presented and the outstanding ones, including Magnoliaceae, Zingiberaceae, Cycadaceae, medicinal plants, Actinidia and Rhododendron are particularly mentioned. With special reference to Chinese penjing art garden and silicified wood garden, the development of scientific popularization and tourism in BGs is reviewed. 展开更多
关键词 botanical garden BIODIVERSITY plant conservation medicinal plant plant introduction and acclimatization plant breeding plant collection
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The Study on the Localization of Acid Phosphatase Activity During Spermiogenesis in Chinese Mitten-Handed Crab,Eriocheir sinensis
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作者 刘桂荣 康现江 +2 位作者 郭明申 孙文佳 王琦 《Marine Science Bulletin》 CAS 2007年第1期13-19,共7页
Ultrastructural cytochemical techniques and electron microscopy were used for localization of acid phosphatase activity during spermiogenesis in Eriocheir sinemsis. The results showed that: Acid phosphatase was synth... Ultrastructural cytochemical techniques and electron microscopy were used for localization of acid phosphatase activity during spermiogenesis in Eriocheir sinemsis. The results showed that: Acid phosphatase was synthesized in the endoplasmic reticulum in the early spermatids. The acid phosphatase was found gradually in nucleus, the membrane of acrosomal vesicle, the cytoplasmic region and the acrosomal tubule. And then the reaction product particles became thicker during the spermiogenesis. In the mature sperm, acid phosphatase was localized in the percutor organ slightly, but it was massive and compact in the acrosomal tubule. 展开更多
关键词 SPERMIOGENESIS Acid phosphatase Eriocheir sinensis
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Effects of Applying Bio-bacterial Fertilizer on Aroma Components of Flue-cured Tobacco
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作者 景延秋 高玉珍 +7 位作者 王卫峰 朱金峰 袁秀秀 张豹林 程玉渊 李怀奇 张月华 鲁平 《Agricultural Science & Technology》 CAS 2015年第6期1209-1211,1215,共4页
Objective] This research aimed to investigate the effects of bio-bacterial fertilizer on quality of flue-curved tobacco. [Method] The various concentrations of bio-bacterial fertilizer were applied to flue-cured tobac... Objective] This research aimed to investigate the effects of bio-bacterial fertilizer on quality of flue-curved tobacco. [Method] The various concentrations of bio-bacterial fertilizer were applied to flue-cured tobacco as leaf fertilizer and base fertilizer respectively. [Result] The effect of bio-bacterial fertilizer on flue-cured tobac-co differed among different treatments. Compared with the control, the bio-bacterial fertilizer significantly affected the quality of flue-cured tobacco. Among al the treat-ments, Treatment 3(leaf fertilizer) showed the best treatment effect, and it significant-ly improved the quality of flue-cured tobacco. [Conclusion] The bio-bacterial fertilizer showed significant improving effect on quality of flue-cured tobacco if spayed as leaf fertilizer. 展开更多
关键词 Bio-bacterial fertilizer Plasmid pigment Neutral aroma components Flue-cured tobacco
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Dynamic change of arborous species diversity in natural secondary forests after selective cutting on the north slope of Changbai Mountain, Northeast China
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作者 金永焕 周莉 +3 位作者 谷会岩 代力民 申光日 刘军 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期299-302,共4页
The community characteristics of natural secondary forests on the north slope of Changbai Mountain after selective cutting were investigated, and the dynamics of arborous species diversity during the restoration perio... The community characteristics of natural secondary forests on the north slope of Changbai Mountain after selective cutting were investigated, and the dynamics of arborous species diversity during the restoration period of 28 years were studied. The results showed that the arborous species richness (S) had little change and kept the range of 18-22 all along, the Simpson index (D) of the secondary layer and regeneration layer and whole stand had similar trends of change, but that of the canopy layer descended slowly in initial 15 years and had little change later, and the change of diversity index was not obvious and the Shannon-Wiener index (H? fluctuated in a very small scopes (H±10%). 展开更多
关键词 Arborous species diversity Natural secondary forests Selective cutting Northeast China
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Bird functional traits affect seed dispersal patterns of China's endangered trees across different disturbed habitats 被引量:7
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作者 Ning Li Zheng Wang +1 位作者 Xinhai Li Zhaohui Li 《Avian Research》 CSCD 2018年第2期144-149,共6页
Background: The most dominant global threat to natural forests and their biodiversity is land-cover change, which has negative impacts on both species persistence and ecosystem functions. Land-cover change could alter... Background: The most dominant global threat to natural forests and their biodiversity is land-cover change, which has negative impacts on both species persistence and ecosystem functions. Land-cover change could alter animal behaviour and disrupt seed dispersal mutualisms. However, its effects on the role of bird functional traits in seed dispersal are not well studied.Methods: In the present study, we assessed the contributions of bird functional traits(behavioural traits: food habit, foraging pattern, foraging frequency, and habitat specialisation; morphological traits: weight, body length, wing length, and tail length) to both seed removal patterns and seed dispersal distances of an endangered and native tree species, Chinese yew(Taxus chinensis), in farmland, patchy habitat, and natural habitat, of southeast China.Results: We found that the ability of T. chinensis trees to form seed dispersal mutualisms with local birds varied across the different disturbed habitats. As a consequence of these mutualisms, more seeds were removed by birds from the patchy habitat than from the other two habitats. The number of seeds removed increased with bird foraging frequency. Moreover, the dispersal distance from the three habitats differed, and the longest dispersal distances were observed at both the patchy habitat and the farmland site. Seed dispersal distance increased with bird tail and wing length.Conclusions: Our results highlight the importance of bird functional traits in the seed dispersal patterns of endangered trees across disturbed forest habitats, which should be considered for tree conservation and management. 展开更多
关键词 Functional traits Seed dispersal Frugivorous birds Behavioural traits Morphological traits
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Relationship between Living Rate of Bud and Emergence Rate of Ratoon Rice and Characteristics of the First Cropping Mid-season Hybrid Rice
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作者 张林 熊洪 +4 位作者 徐富贤 朱永川 郭晓艺 周兴兵 刘茂 《Agricultural Science & Technology》 CAS 2012年第9期1873-1876,1895,共5页
[Objective] The aim was to study the relationship of plant characters with bud living rate and mother stem emergence rate of ratoon rice before harvest. [Method] Eighteen mid-season hybrid rice cultivators approved re... [Objective] The aim was to study the relationship of plant characters with bud living rate and mother stem emergence rate of ratoon rice before harvest. [Method] Eighteen mid-season hybrid rice cultivators approved recently were taken as materials and relationship of plant characters including bud living rate and moth- er stem emergence rate of ratoon rice before harvest was explored, based on relat- ed data. [Result] The shorter rice with lower harvesting index is the main character of high emergence rate for first cropping rice; decline of plant height and increase of ear-bearing percentage would improve emergence of regenerative seedlings. [Conclusion] The research provided scientific reference for breeding of rice cultivars with high regenerative capacity. 展开更多
关键词 Mid-season hybrid rice Plant characters Bud living rate Emergencerate
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Differences of Physiological and Biochemical Indexes of Upper Fresh Leaves and Post-growth Roots in Different Quality Stages 被引量:1
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作者 谢碧君 裴晓东 +5 位作者 邓小华 蔡兴 何命军 李帆 黄松青 陈金 《Agricultural Science & Technology》 CAS 2017年第11期2033-2036,2044,共5页
In order to explore the physiological and biochemical characteristics of fresh upper leaves and roots of different qualities of tobacco, the malonaldehyde (MDA), superoxide dismutase (SOD) activity, chlorophyllase... In order to explore the physiological and biochemical characteristics of fresh upper leaves and roots of different qualities of tobacco, the malonaldehyde (MDA), superoxide dismutase (SOD) activity, chlorophyllase activity, amylase activity, medium trace element content, chemical component content, root fresh weight, dry weight and activity in the normal tobacco leaves, tobacco leaves rich in nutrients and premature grey tobacco leaves were studied. The results showed that compared with the normal tobacco leaves, the root fresh weight, dry weight and activity in the premature grey tobacco leaves decreased by 41.22%, 14.44% and 60.29% respectively, while malonaldehyde content increased by 34.82%, and chlorophyllase, α-amylase, β-amylase and SOD activity declined by 89.55%, 65.71%, 71.26% and 37.25% respectively. Chlorophyllase, co-amylase and 13-amylase activity in the tobacco leaves rich in nutrients decreased by 58.76%, 36.19% and 41.93% respectively. The content of medium trace elements in the tobacco leaves rich in nutrients and premature grey tobacco leaves was lower than that of the normal tobacco leaves. Starch, total sugar, reducing sugar and potassium content in the normal tobacco leaves were higher than that of the tobacco leaves rich in nutrients and premature grey tobacco leaves. 展开更多
关键词 Upper tobacco leaves Root activity Physiological and biochemical properties Medium trace elements Chemical components
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Three new species of Batrachospermum Roth (Batrachosper-maceae,Rhodophyta) in China 被引量:5
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作者 谢树莲 施之新 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第2期204-209,共6页
Three new species of Batrachospermum Roth (Batrachospermales, Rhodophyta) from China are described in this paper. B. yunnanense sp. nov. has long-cylindrical trichogynes with long stalks and is diagnostic of section V... Three new species of Batrachospermum Roth (Batrachospermales, Rhodophyta) from China are described in this paper. B. yunnanense sp. nov. has long-cylindrical trichogynes with long stalks and is diagnostic of section Virescentia. Within this section, B. yunnanense is similar to B. helminthosum Bory emend. Sheath et al., but it is dioecious and has curved carpogonial branches, while the latter is monoecious and has straight carpogonial branches. It is also similar to B. transtaganum Reis, but it differs from the latter in long carpogonia, big carposporophytes and carposporangia. It is considered that B. nothocladoideum sp. nov. is assigned to section Contorta, subsection Kushiroense, because its carpogonial branches are twisted and gonimoblast filaments are loosely agglomerated. This new species similar to B. iriomotense Kumano, but with short fascicles, long-ovoid or subpyriform cells, numerous terminal hairs, long-ellipsoid trichogynes, big carposporophytes and small carpo- sporangia. The plant is quite tough and cartilaginous and similar to Nothocladus in gross morphology, but its carposporophytes are compact instead of diffuse. This shows that it may be a transitional species between section Contorta and genus Nothocladus. So, B. transitorium sp. nov. should belong to section Contorta, subsection Kushiroense, because of its curved or twisted carpogonial branches and loosely agglomerated gonimoblast filaments, with globose or subglobose cells in fascicles similar to B. spermatiophorum Vis et Sheath, but no colourless spermatiophores. In terms of small and numerous carposporophytes, B. transitorium sp. nov. is similar to some species of section Batrachospermum. However, their other features are unique, indicating its transitional nature between section Contorta and Batrachospermum. 展开更多
关键词 freshwater red algae Batrachospermum B. yunnanense S. L. Xie et Z. X. Shi B. nothocladoideum S. L. Xie et Z. X. Shi B. transitorium S. L. Xie et Z. X. Shi new species China
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Pollination ecology in China from 1977 to 2017 被引量:5
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作者 Zongxin Ren Yanhui Zhao +4 位作者 Huan Liang Zhibin Tao Hui Tang Haiping Zhang Hong Wang 《Plant Diversity》 SCIE CAS CSCD 2018年第4期172-180,共9页
China is one of most biodiverse countries in the world, containing at least 10% of all angiosperm species.Therefore, we should anticipate a diverse, pollinator fauna. China also has a long history of applied ethnobiol... China is one of most biodiverse countries in the world, containing at least 10% of all angiosperm species.Therefore, we should anticipate a diverse, pollinator fauna. China also has a long history of applied ethnobiology, including a sustainable agriculture based on apiculture and plant-pollinator interactions.However, the science of pollination ecology is a far younger sub-discipline in China, compared to in the West. Chinese studies in pollination ecology began in the 1970 s. For this review, we compiled a complete reference database(>600 publications) of pollination studies in China. Using this database, we identified and analyzed gaps and limitations in research on the pollination systems of native and naturalized species. Specifically, we asked the following questions: 1) What do we know about the pollination systems of native, Chinese species? 2) How does Chinese pollination ecology compare with the development of pollination research abroad and which aspects of research should be pursued by Chinese anthecologists in the near future? 3) What research on pollination in China will advance our understanding and contribute to our ongoing analyses of endemism and conservation? Subsequently, we segregated and identified prospective lines of future research that are unique to China and can only be done in China. This requires discussing priorities within a systematic approach. 展开更多
关键词 China BIODIVERSITY CONSERVATION HIMALAYAS POLLINATION POLLINATORS
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Neutral Complex Extraction and Synergistic Extraction of Macrolide Antibiotics 被引量:1
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作者 李洲 秦峰 +2 位作者 鲍浩 谷雪蔷 戴玲妹 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2000年第4期304-309,共6页
Based on the theory of reactive extraction, new solvent systems were developed to replace butylacetate for extraction of macrolide antibiotics (erythromycin, kitasamycin, spiramycin meleumycin etc.). A new neutral com... Based on the theory of reactive extraction, new solvent systems were developed to replace butylacetate for extraction of macrolide antibiotics (erythromycin, kitasamycin, spiramycin meleumycin etc.). A new neutral complex solvent extraction system, fatty alcohol-kerosene (marked by El), was used for extraction of erythromycin, one of the macrolide antibiotics. The extraction equilibrium equation is obtained, and the extraction distribution is as followsD = exp (-36.33×103/RT + 18.77)[B](o)1.1/(1 + 108.07-PH)The effects of several parameters on extraction equilibrium were investigated. Furthermore, a new synergistic extraction system (marked by E2) was developed, in which another solvent was used as synergistic agent to replace the diluent kerosene in the neutral complex extraction system. Based on these new extraction systems, an improved process for extraction of erythromycin was developed, showing remarkable advantages in technology and economics owing to its low solvent consumption of 3kg per billion unit compared with 9—10 for butylacetate. The recovery process of solvent from raffinate may be eliminated. 展开更多
关键词 macrolide antibiotics ERYTHROMYCIN neutral complex extraction synergistic extraction
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