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SIP高度可用性和可靠性的新范例
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作者 Contributed by F5Networks.Inc 《世界电信》 2004年第6期54-55,共2页
关键词 会话初始化协议 SIP 高度可用性 可靠性 代理服务器 服务质量
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Treatment of gastric cancer 被引量:121
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作者 Michele Orditura Gennaro Galizia +10 位作者 Vincenzo Sforza Valentina Gambardella Alessio Fabozzi Maria Maddalena Laterza Francesca Andreozzi Jole Ventriglia Beatrice Savastano Andrea Mabilia Eva Lieto Fortunato Ciardiello Ferdinando De Vita 《World Journal of Gastroenterology》 SCIE CAS 2014年第7期1635-1649,共15页
The authors focused on the current surgical treatment of resectable gastric cancer, and significance of peri- and post-operative chemo or chemoradiation. Gastric cancer is the 4<sup>th</sup> most commonly ... The authors focused on the current surgical treatment of resectable gastric cancer, and significance of peri- and post-operative chemo or chemoradiation. Gastric cancer is the 4<sup>th</sup> most commonly diagnosed cancer and the second leading cause of cancer death worldwide. Surgery remains the only curative therapy, while perioperative and adjuvant chemotherapy, as well as chemoradiation, can improve outcome of resectable gastric cancer with extended lymph node dissection. More than half of radically resected gastric cancer patients relapse locally or with distant metastases, or receive the diagnosis of gastric cancer when tumor is disseminated; therefore, median survival rarely exceeds 12 mo, and 5-years survival is less than 10%. Cisplatin and fluoropyrimidine-based chemotherapy, with addition of trastuzumab in human epidermal growth factor receptor 2 positive patients, is the widely used treatment in stage IV patients fit for chemotherapy. Recent evidence supports the use of second-line chemotherapy after progression in patients with good performance status 展开更多
关键词 Gastric cancer SURGERY RADIOTHERAPY Adjuvant chemotherapy Palliative chemotherapy CHEMORADIATION
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MYB Transcription Factors as Regulators of Phenylpropanoid Metabolism in Plants 被引量:91
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作者 Jingying Liu Anne Osbourm Pengda Ma 《Molecular Plant》 SCIE CAS CSCD 2015年第5期689-708,共20页
Phenylpropanoid-derived compounds represent a diverse family of secondary metabolites that originate from phenylalanine. These compounds have roles in plant growth and development, and in defense against biotic and ab... Phenylpropanoid-derived compounds represent a diverse family of secondary metabolites that originate from phenylalanine. These compounds have roles in plant growth and development, and in defense against biotic and abiotic stress. Many of these compounds are also beneficial to human health and welfare. V-myb myeloblastosis viral oncogene homolog (MYB) proteins belong to a large family of transcription factors and are key regulators of the synthesis of phenylpropanoid-derived compounds. This review summarizes the current understanding of MYB proteins and their roles in the regulation of phenylpropanoid metabolism in plants. 展开更多
关键词 MYB MONOLIGNOL flavonoid phenolic acid STILBENE
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小麦指纹图谱数据库的建立及SSR分子标记试剂盒的研发 被引量:64
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作者 李根英 Susanne Dreisigacker +3 位作者 Marilyn L.Warburton 夏先春 何中虎 孙其信 《作物学报》 CAS CSCD 北大核心 2006年第12期1771-1778,共8页
本研究以国际玉米小麦改良中心(CIMMYT)、国际干旱地区农业研究中心(ICARDA)、法国Agropolis研究所和中国农业科学院作物科学研究所提供的数据为基础,建立了包括134个SSR引物、2457个普通小麦基因型的指纹图谱数据库。利用荧光标记法的... 本研究以国际玉米小麦改良中心(CIMMYT)、国际干旱地区农业研究中心(ICARDA)、法国Agropolis研究所和中国农业科学院作物科学研究所提供的数据为基础,建立了包括134个SSR引物、2457个普通小麦基因型的指纹图谱数据库。利用荧光标记法的分析结果,用代表性基因型在某一位点的扩增片段作为银染法的读带依据,开发了SSR分子标记试剂盒,包括46对SSR引物及其PCR反应程序、代表性基因型的DNA样品、592个等位变异的代表性基因型清单及试剂盒使用说明等。该数据库的建立和试剂盒的开发,为利用SSR分子标记技术进行小麦种质遗传多样性研究,实现小麦遗传资源和信息资源全球共享提供了重要工具和技术平台。 展开更多
关键词 小麦 指纹图谱 数据库 SSR引物 标准基因型 试剂盒
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Immobilization of Lead and Cadmium in Contaminated Soil Using Amendments: A Review 被引量:59
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作者 Amanullah MAHAR WANG Ping +1 位作者 LI Ronghua ZHANG Zengqiang 《Pedosphere》 SCIE CAS CSCD 2015年第4期555-568,共14页
Since the inception of industrial revolution, metal refining plants using pyrometallurgical processes have generated the prodigious emissions of lead(Pb) and cadmium(Cd). As the core target of such pollutants, a large... Since the inception of industrial revolution, metal refining plants using pyrometallurgical processes have generated the prodigious emissions of lead(Pb) and cadmium(Cd). As the core target of such pollutants, a large number of soils are nowadays contaminated over widespread areas, posing a great threat to public health worldwide. Unlike organic pollutants, Pb and Cd do not undergo chemical or microbial breakdown and stay likely in site for longer duration after their release. Immobilization is an in-situ remediation technique that uses cost-effective soil amendments to reduce Pb and Cd availability in the contaminated soils. The Pb and Cd contamination in the soil environment is reviewed with focus on source enrichment, speciation and associated health risks, and immobilization options using various soil amendments. Commonly applied and emerging cost-effective soil amendments for Pb and Cd immobilization include phosphate compounds, liming, animal manure, biosolids, metal oxides, and biochar. These immobilizing agents could reduce the transfer of metal pollutants or residues to food web(plant uptake and leaching to subsurface water) and their long-term sustainability in heavy metal fixation needs further assessment. 展开更多
关键词 BIOAVAILABILITY BIOCHAR BIOSOLIDS heavy metal public health REMEDIATION soil extraction
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Risk for colorectal cancer in ulcerative colitis:Changes,causes and management strategies 被引量:58
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作者 Peter Laszlo Lakatos Laszlo Lakatos 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第25期3937-3947,共11页
The risk of colorectal cancer for any patient with ulcer-ative colitis is known to be elevated, and is estimated to be 2% after 10 years, 8% after 20 years and 18% after 30 years of disease. Risk factors for cancer in... The risk of colorectal cancer for any patient with ulcer-ative colitis is known to be elevated, and is estimated to be 2% after 10 years, 8% after 20 years and 18% after 30 years of disease. Risk factors for cancer in-clude extent and duration of ulcerative colitis, primary sclerosing cholangitis, a family history of sporadic colorectal cancer, severity of histologic bowel inflam-mation, and in some studies, young age at onset of colitis. In this review, the authors discuss recent epide-miological trends and causes for the observed chang-es. Population-based studies published within the past 5 years suggest that this risk has decreased over time, despite the low frequency of colectomies. The crude annual incidence rate of colorectal cancer in ulcerative colitis ranges from approximately 0.06% to 0.16% with a relative risk of 1.0-2.75. The exact mechanism for this change is unknown; it may partly be explained by the more widespread use of maintenance therapy and surveillance colonoscopy. 展开更多
关键词 Ulcerative colitis Colorectal cancer RISKFACTORS SURVEILLANCE Chemprevention
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Potential and challenges of tannins as an alternative to in-feed antibiotics for farm animal production 被引量:57
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作者 Qianqian Huang Xiuli Liu +2 位作者 Guoqi Zhao Tianming Hu Yuxi Wang 《Animal Nutrition》 SCIE 2018年第2期137-150,共14页
Naturally occurring plant compounds including tannins, saponins and essential oils are extensively assessed as natural alternatives to in-feed antibiotics.Tannins are a group of polyphenolic compounds that are widely ... Naturally occurring plant compounds including tannins, saponins and essential oils are extensively assessed as natural alternatives to in-feed antibiotics.Tannins are a group of polyphenolic compounds that are widely present in plant region and possess various biological activities including antimicrobial,anti-parasitic, anti-viral, antioxidant, anti-inflammatory, immunomodulation, etc.Therefore, tannins are the major research subject in developing natural alternative to in-feed antibiotics.Strong protein affinity is the well-recognized property of plant tannins, which has successfully been applied to ruminant nutrition to decrease protein degradation in the rumen, and thereby improve protein utilization and animal production efficiency.Incorporations of tannin-containing forage in ruminant diets to control animal pasture bloat, intestinal parasite and pathogenic bacteria load are another 3 important applications of tannins in ruminant animals.Tannins have traditionally been regarded as "anti-nutritional factor" for monogastric animals and poultry, but recent researches have revealed some of them, when applied in appropriate manner, improved intestinal microbial ecosystem, enhanced gut health and hence increased productive performance.The applicability of plant tannins as an alternative to in-feed antibiotics depends on many factors that contribute to the great variability in their observed efficacies. 展开更多
关键词 TANNINS Biological activities In-feed antibiotics Natural feed additives Farm animal
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Immunopathology of inflammatory bowel disease 被引量:48
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作者 Kori L Wallace Li-Bo Zheng +1 位作者 Yoshitake Kanazawa David Q Shih 《World Journal of Gastroenterology》 SCIE CAS 2014年第1期6-21,共16页
Inflammatory bowel disease (IBD) results from a complex series of interactions between susceptibility genes, the environment, and the immune system. The host microbiome, as well as viruses and fungi, play important ro... Inflammatory bowel disease (IBD) results from a complex series of interactions between susceptibility genes, the environment, and the immune system. The host microbiome, as well as viruses and fungi, play important roles in the development of IBD either by causing inflammation directly or indirectly through an altered immune system. New technologies have allowed researchers to be able to quantify the various components of the microbiome, which will allow for future developments in the etiology of IBD. Various components of the mucosal immune system are implicated in the pathogenesis of IBD and include intestinal epithelial cells, innate lymphoid cells, cells of the innate (macrophages/monocytes, neutrophils, and dendritic cells) and adaptive (T-cells and B-cells) immune system, and their secreted mediators (cytokines and chemokines). Either a mucosal susceptibility or defect in sampling of gut luminal antigen, possibly through the process of autophagy, leads to activation of innate immune response that may be mediated by enhanced toll-like receptor activity. The antigen presenting cells then mediate the differentiation of na&#x000ef;ve T-cells into effector T helper (Th) cells, including Th1, Th2, and Th17, which alter gut homeostasis and lead to IBD. In this review, the effects of these components in the immunopathogenesis of IBD will be discussed. 展开更多
关键词 Inflammatory bowel disease Crohn’ s disease Ulcerative colitis Microbiome Autophagy T helper 17 Innate immune system Adaptive immune system Innate lymphoid cells TL1A
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Response of microbial communities to biochar-amended soils:a critical review 被引量:47
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作者 Kumuduni Niroshika Palansooriya James Tsz Fung Wong +6 位作者 Yohey Hashimoto Longbin Huang Jörg Rinklebe Scott X.Chang Nanthi Bolan Hailong Wang Yong Sik Ok 《Biochar》 2019年第1期3-22,共20页
Application of biochar to soils changes soil physicochemical properties and stimulates the activities of soil microorganisms that influence soil quality and plant performance.Studying the response of soil microbial co... Application of biochar to soils changes soil physicochemical properties and stimulates the activities of soil microorganisms that influence soil quality and plant performance.Studying the response of soil microbial communities to biochar amendments is important for better understanding interactions of biochar with soil,as well as plants.However,the effect of biochar on soil microorganisms has received less attention than its influences on soil physicochemical properties.In this review,the following key questions are discussed:(i)how does biochar affect soil microbial activities,in particular soil carbon(C)mineralization,nutrient cycling,and enzyme activities?(ii)how do microorganisms respond to biochar amendment in contaminated soils?and(iii)what is the role of biochar as a growth promoter for soil microorganisms?Many studies have demonstrated that biochar-soil application enhances the soil microbial biomass with substantial changes in microbial community composition.Biochar amendment changes microbial habitats,directly or indirectly affects microbial metabolic activities,and modifies the soil microbial community in terms of their diversity and abundance.However,chemical properties of biochar,(especially pH and nutrient content),and physical properties such as pore size,pore volume,and specific surface area play significant roles in determining the efficacy of biochar on microbial performance as biochar provides suitable habitats for microorgan-isms.The mode of action of biochar leading to stimulation of microbial activities is complex and is influenced by the nature of biochar as well as soil conditions. 展开更多
关键词 Carbon cycling Microbial habitat MICROORGANISMS Nutrient cycling Enzyme activity
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Effects of dietary supplementation of probiotic,Clostridium butyricum,on growth performance,immune response,intestinal barrier function,and digestive enzyme activity in broiler chickens challenged with Escherichia coli K88 被引量:46
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作者 Ling Zhang Lingling Zhang +5 位作者 Xiu'an Zhan Xinfu Zeng Lin Zhou Guangtian Cao An'guo Chen Caimei Yang 《Journal of Animal Science and Biotechnology》 CAS CSCD 2016年第1期107-115,共9页
Background: Colibacillosis caused by enterotoxigenic Escherichia coil (E. coil} results in economic losses in the poultry industry. Antibiotics are usually used to control colibacillosis, however, E. coli has varyin... Background: Colibacillosis caused by enterotoxigenic Escherichia coil (E. coil} results in economic losses in the poultry industry. Antibiotics are usually used to control colibacillosis, however, E. coli has varying degrees of resistance to different antibiotics. Therefore the use of probiotics is becoming accepted as an alternative to antibiotics. In this study, we evaluated the effects of Clostfidium butyricum (C. butyficum) on growth performance, immune response, intestinal barrier function, and digestive enzyme activity in broiler chickens challenged with Eschefichia coli (E. coil) K88. Methods: The chickens were randomly divided into four treatment groups for 28 days. Negative control treatment (NC) consisted of birds fed a basal diet without E. coil K88 challenge and positive control treatment (PC) consisted of birds fed a basal diet and challenged with E. coil K88. C. buO/ricum probiotic treatment (CB) consisted of birds fed a diet containing 2 x 107 cfu C. buO/ricum/kg of diet and challenged with E. coil K88. Colistin sulfate antibiotic treatment (CS) consisted of birds fed a diet containing 20 mg colistin sulfate/kg of diet and challenged with E. coil K88. Results: The body weight (BW) and average day gain (ADG) in the broilers of CB group were higher (P 〈 0.05) than the broilers in the PC group overall except the ADG in the 14-21 d post-challenge. The birds in CB treatment had higher (P 〈 0.05) concentration of tumor necrosis factor-a (TNF-a) at 3 and 7 d post-challenge, and higher (P 〈 0.05) concentration of interleukin-4 (IL-4) at 14 d post-challenge than those in the PC treatment group. The concentration of serum endotoxin in CB birds was lower (P 〈 0.05) at 21 d post-challenge, and the concentrations of serum diamine oxidase in CB birds were lower (P 〈 0.05) at 14 and 21 d post-challenge than in PC birds. Birds in CB treatment group had higher (P 〈 0.05) jejunum villi height than those in PC, NC, or CS treatment at 展开更多
关键词 Broiler chickens Clostridium butyricum Digestive enzyme activity Escherichia coli K88 Growth performance Immune response Intestinal barrier
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Impact of oxygation on soil respiration, yield and water use efficiency of three crop species 被引量:46
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作者 Xinming Chen Jay Dhungel +3 位作者 Surya P.Bhattarai Manouchehr Torabi Lance Pendergast David J.Midmore 《Journal of Plant Ecology》 SCIE 2011年第4期236-248,共13页
Oxygation refers to irrigation of crops with aerated water,through air injection using the venturi principle or the supply of hydrogen peroxide in the root zone,both using subsurface drip irrigation(SDI)system.Oxygati... Oxygation refers to irrigation of crops with aerated water,through air injection using the venturi principle or the supply of hydrogen peroxide in the root zone,both using subsurface drip irrigation(SDI)system.Oxygation improves water use efficiency(WUE),producing more yield and,and therefore,optimizes the use of drip and SDI.But the efficiency of oxygation is quite possibly dependent on a number of factors.The primary objective of this study was,therefore,to quantify the effects of oxygation,emitter depths and soil type on crop root zone oxygen content,soil respiration,plant physiological response,biomass yield,quality and WUE of three crop species.Methods This study investigated the potential of oxygation to enhance soil respiration,plant growth,yield and water use efficiencies(WUE)of cotton and wheat in experiments in enclosed heavy-duty concrete troughs(tubs)and pineapple and cotton in field experiments.Experimental treatments in tubs for wheat included comparisons between two soil types(vertisol and ferrosol)and superimposed were two oxygation methods(Mazzei air injector and Seair Diffusion System)compared to a control,and for cotton,emitters at two depths using Mazzei air injectors were compared to a control.The field experiments compared Mazzei air injectors and a control for cotton in Emerald and pineapple in Yeppoon,both in central Queensland,Australia.Important findings In all experiments,soil oxygen content and soil respiration markedly increased in response to the oxygation treatments.The O2 concentration in the crop root zone increased by 2.4–32.6%,for oxygation compared to control at the same depth.The soil respiration increased by 42–100%.The number of wheat ears,leaf dry weight and total dry matter were significantly greater in Mazzei and Seair oxygation compared to the control.Fresh biomass of wheat increased by 11 and 8%,and dry weight of wheat increased by 8 and 3%in Mazzei and Seair oxygation treatments compared to the control,respectively.Likewise,the irrigation water use efficiency incre 展开更多
关键词 oxygation subsurface drip irrigation soil respiration YIELD water use efficiencies
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美国临床肿瘤学会IV期非小细胞肺癌化疗的临床实践指南更新 被引量:43
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作者 Christopher G. AZZOLI Sherman Baker JR +21 位作者 Sarah TEMIN William PAO Timothy ALIFF Julie BRAHMER David H. JOHNSON Janessa L. LASKIN Gregory MASTERS Daniel MILTON Luke NORDQUIST David G. PFISTER Steven PIANTADOSI Joan H. SCHILLER Reily SMITH Thomas J. SMITH John R. STRAWN David TRENT Giuseppe GIACCONE 丁燕(翻译) 南娟(翻译) 刘谦(翻译) 周清华(校对) 陈军(校对) 《中国肺癌杂志》 CAS 2010年第3期171-189,共19页
本文旨在为IV期非小细胞肺癌患者的治疗提供更新版推荐。本文资料检索源自2002年以来公布的相关随机试验文献。此指南范围限于化疗与生物治疗。更新委员会对这些文献进行了总结并提供了推荐更新。162篇文献符合标准被纳入参考。本推荐... 本文旨在为IV期非小细胞肺癌患者的治疗提供更新版推荐。本文资料检索源自2002年以来公布的相关随机试验文献。此指南范围限于化疗与生物治疗。更新委员会对这些文献进行了总结并提供了推荐更新。162篇文献符合标准被纳入参考。本推荐基于可改善总生存期的治疗方法。仅改善无进展生存期的治疗方法推动了对毒性及生存质量的监测。对于体力状态评分为0分或1分患者的一线治疗,可推荐以铂类为基础的细胞毒性药物的两药联用。对铂类治疗有禁忌的患者,可采用非铂类细胞毒性两药联合。对于体力状态评分为2分的患者,单一细胞毒性药物即可。对于疾病进展或经过4个周期的治疗仍对治疗无反应的患者,应停止一线细胞毒性化疗。即使在6个周期后患者对治疗仍有反应,亦应停止两药细胞毒性化疗。对于伴有明确的表皮生长因子受体(epidermal growth factor receptor,EGFR)突变的患者,可推荐一线采用吉非替尼治疗;对于EGFR突变为阴性或不明确的患者,细胞毒性化疗更佳。除具有特定临床特征的患者外,可推荐贝伐单抗与卡铂-紫杉醇联用。对于通过免疫组化证实EGFR阳性的肿瘤患者,可推荐西妥昔单抗与顺铂-长春瑞滨联用。多西紫杉醇、厄洛替尼、吉非替尼或培美曲塞被推荐作为二线治疗。对于未曾接受过厄洛替尼或吉非替尼治疗的患者,可推荐厄洛替尼作为三线治疗。现有数据不足以推荐常规三线采用细胞毒性药物。已有的证据也不足以推荐常规应用分子标记物选择化疗。 展开更多
关键词 临床实践指南 非小细胞肺癌 选择化疗 美国临床肿瘤学会 细胞毒性药物 表皮生长因子受体 RECEPTOR 肺癌患者
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A scientometric review of biochar research in the past 20 years(1998-2018) 被引量:43
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作者 Ping Wu Syed Tahir Ata-Ul-Karim +7 位作者 Bhupinder Pal Singh Hailong Wang Tongliang Wu Cun Liu Guodong Fang Dongmei Zhou Yujun Wang Wenfu Chen 《Biochar》 2019年第1期23-43,共21页
Biochar is the carbon-rich product obtained from the thermochemical conversion of biomass under oxygen-limited conditions.Biochar has attained extensive attention due to its agronomical and environmental benefits in a... Biochar is the carbon-rich product obtained from the thermochemical conversion of biomass under oxygen-limited conditions.Biochar has attained extensive attention due to its agronomical and environmental benefits in agro-ecosystems.This work adopts the scientometric analysis method to assess the development trends of biochar research based on the literature data retrieved from the Web of Science over the period of 1998-2018.By analysing the basic characteristics of 6934 publications,we found that the number of publications grew rapidly since 2010.Based on a keyword analysis,it is concluded that scholars have had a fundamental recognition of biochar and preliminarily found that biochar application had agronomic and environmental benefits during the period of 1998-2010.The clustering results of keywords in documents published during 2011-2015 showed that the main research hotspots were“biochar production”,“biochar and global climate change”,“soil quality and plant growth”,“organic pollutants removal”,and“heavy metals immobilization”.While in 2016-2018,beside these five main research hotspots,“biochar and composting”topic had also received greater attention,indicating that biochar utilization in organic solid waste composting is the current research hotspot.Moreover,updated reactors(e.g.,microwave reactor,fixed-bed reactor,screw-feeding reactor,bubbling fluidized bed reactor,etc.)or technologies(e.g.,solar pyrolysis,Thermo-Catalytic Reforming process,liquefaction technology,etc.)applied for efficient energy production and modified biochar for environmental remediation have been extensively studied recently.The findings may help the new researchers to seize the research frontier in the biochar field. 展开更多
关键词 BIOCHAR CiteSpace Research hotspots COMPOSTING Energy MODIFICATION
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Intestinal barrier in inflammatory bowel disease 被引量:40
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作者 Lena Antoni Sabine Nuding +1 位作者 Jan Wehkamp Eduard F Stange 《World Journal of Gastroenterology》 SCIE CAS 2014年第5期1165-1179,共15页
A complex mucosal barrier protects as the first line of defense the surface of the healthy intestinal tract from adhesion and invasion by luminal microorganisms. In this review, we provide an overview about the major ... A complex mucosal barrier protects as the first line of defense the surface of the healthy intestinal tract from adhesion and invasion by luminal microorganisms. In this review, we provide an overview about the major components of this protective system as for example an intact epithelium, the synthesis of various antimicrobial peptides (AMPs) and the formation of the mucus layer. We highlight the crucial importance of their correct functioning for the maintenance of a proper intestinal function and the prevention of dysbiosis and disease. Barrier disturbances including a defective production of AMPs, alterations in thickness or composition of the intestinal mucus layer, alterations of pattern-recognition receptors, defects in the process of autophagy as well as unresolved endoplasmic reticulum stress result in an inadequate host protection and are thought to play a crucial role in the pathogenesis of the inflammatory bowel diseases Crohn&#x02019;s disease and ulcerative colitis. 展开更多
关键词 Intestinal barrier Antimicrobial peptide Mucus layer Inflammatory bowel disease Crohn’ s disease Ulcerative colitis Goblet cell Paneth cell
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Spatial Variability of Soil Organic Carbon in a Watershed on the Loess Plateau 被引量:37
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作者 WANG Yun-Qiang ZHANG Xing-Chang +1 位作者 ZHANG Jing-Li LI Shun-Ji 《Pedosphere》 SCIE CAS CSCD 2009年第4期486-495,共10页
Soil organic carbon (SOC) has great impacts on global warming, land degradation and food security. Classic statistical and geostatistical methods were used to characterize and compare the spatial heterogeneity of SOC ... Soil organic carbon (SOC) has great impacts on global warming, land degradation and food security. Classic statistical and geostatistical methods were used to characterize and compare the spatial heterogeneity of SOC and related factors, such as topography, soil type and land use, in the Liudaogou watershed on the Loess Plateau of North China. SOC concentrations followed a log-normal distribution with an arithmetic and geometric means of 23.4 and 21.3 g kg-1, respectively, were moderately variable (CV = 75.9%), and demonstrated a moderate spatial dependence according to the nugget ratio (34.7%). The experimental variogram of SOC was best-fitted by a spherical model, after the spatial outliers had been detected and subsequently eliminated. Lower SOC concentrations were associated with higher elevations. Warp soils and farmland had the highest SOC concentrations, while aeolian sand soil and shrublands had the lowest SOC values. The geostatistical characteristics of SOC for the different soil and land use types were different. These patterns were closely related to the spatial structure of topography, and soil and land use types. 展开更多
关键词 GEOSTATISTICS land use soil type spatial pattern TOPOGRAPHY
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Engineering Non-transgenic Gynoecious Cucumber Using an Improved Transformation Protocol and Optimized CRISPR/Cas9 System 被引量:35
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作者 Bowen Hu Dawei Li +6 位作者 Xin Liu Jingjing Qi Dongli Gao Shuqiao Zhao Sanwen Huang Jinjing Sun Li Yang 《Molecular Plant》 SCIE CAS CSCD 2017年第12期1575-1578,共4页
Dear Editor,Gynoecism has been extensively exploited in cucumber breeding. The utilization of a gynoecious line permits earlier pro- duction of hybrids, higher yield, and more concentrated fruit set. In addition, the ... Dear Editor,Gynoecism has been extensively exploited in cucumber breeding. The utilization of a gynoecious line permits earlier pro- duction of hybrids, higher yield, and more concentrated fruit set. In addition, the utilization of a gynoecious line eliminates the need for hand emasculation and reduces the labor cost of crossing (Robinson, 2000). Therefore, the development of gynoeoious inbred lines is instrumental for cucumber breeding. Gynoecious inbreds can be produced by selection from crosses of monoecious inbreds, or can arise spontaneously from natural variation. However, both methods have disadvantages. For instance, the time-consuming and laborious process of crossing can also lead to the introduction of undesirable traits, 展开更多
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分娩早期及晚期使用硬膜外镇痛对剖宫产风险的影响 被引量:34
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作者 Wong C.A. Scavone B.M. +1 位作者 Peaceman A.M. 张剑萍 《世界核心医学期刊文摘(妇产科学分册)》 2005年第7期3-4,共2页
BACKGROUND: Epidural analgesia initiated early in labor (when the cervix is less than 4.0 cm dilated) has been associated with an increased risk of cesarean delivery. It is unclear, however, whether this increase in r... BACKGROUND: Epidural analgesia initiated early in labor (when the cervix is less than 4.0 cm dilated) has been associated with an increased risk of cesarean delivery. It is unclear, however, whether this increase in risk is due to the analgesia or is attributable to other factors. METH- ODS: We conducted a randomized trial of 750 nulliparous women at term who were in spontaneous labor or had spontaneous rupture of the membranes and who had a cervical dilatation of less than 4.0 cm. Women were randomly assigned to receive intrathecal fentanyl or systemic hydromorphone at the first request for analgesia. Epidural analgesia was initiated in the intrathecal group at the second request for analgesia and in the systemic group at a cervical dilatation of 4.0 cm or greater or at the third request for analgesia. The primary outcome was the rate of cesarean delivery. RESULTS: The rate of cesarean delivery was not significantly different between the groups (17.8 percent after intrathecal analgesia vs. 20.7 percent after systemic analgesia; 95 percent confidence interval for the difference, - 9.0 to 3.0 percentage points; P=0.31). The median time from the initiation of analgesia to complete dilatation was significantly shorter after intrathecal analgesia than after systemic analgesia (295 minutes vs. 385 minutes, P<0.001), as was the time to vaginal delivery (398 minutes vs. 479 minutes, P<0.001). Pain scores after the first intervention were significantly lower after intrathecal analgesia than after systemic analgesia (2 vs. 6 on a 0- to- 10 scale, P<0.001). The incidence of one- minute Apgar scores below 7 was significantly higher after systemic analgesia (24.0 percent vs. 16.7 percent, P=0.01). CONCLUSIONS: Neuraxial analgesia in early labor did not increase the rate of cesarean delivery, and it provided better analgesia and resulted in a shorter duration of labor than systemic analgesia. 展开更多
关键词 硬膜外镇痛 宫口扩张 静脉镇痛 镇痛分娩 镇痛法 初产妇 镇痛效果 宫口开全 无显著性差异 硬膜外注射
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烷基磷酸酯钾盐抗静电性及其吸湿性研究 被引量:20
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作者 NIU Yu-rong WANG Wen +1 位作者 王文 牛予蓉 《精细化工》 EI CAS CSCD 北大核心 2001年第3期156-158,共3页
从涤纶短纤维的静电产生入手 ,对烷基磷酸酯钾盐在不同温湿度下的抗静电机理以及吸湿性进行了研究。
关键词 油剂 抗静电性 吸湿性 烷基磷酸酯甲盐 涤纶短纤维
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Use of Biochar as an Amendment for Remediation of Heavy Metal-Contaminated Soils:Prospects and Challenges 被引量:30
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作者 Altaf Hussain LAHORI GUO Zhanyu +8 位作者 ZHANG Zengqiang LI Ronghua Amanullah MAHAR Mukesh Kumar AWASTHI SHEN Feng Tanveer Ali SIAL Farhana KUMBHAR WANG Ping JIANG Shuncheng 《Pedosphere》 SCIE CAS CSCD 2017年第6期991-1014,共24页
Biochar(BC), known as the new black gold, is a stable, novel carbonaceous by-product that is synthesized through pyrolysis of biological materials in the absence of O_2.Recently, an emerging interest in the applicatio... Biochar(BC), known as the new black gold, is a stable, novel carbonaceous by-product that is synthesized through pyrolysis of biological materials in the absence of O_2.Recently, an emerging interest in the application of BC as a robust soil amendment has given rise to a broad research area in science and technology.It is considered a promising remediation option for heavy metal(HM)-contaminated soils to reduce HM bioavailability to plants.Remediation efficacy of BC depends on the porosity, composition,pyrolysis temperature, feedstock, and residence time of pyrolysis.This review article aimed to present an overview of BC use in the immobilization of HMs, i.e., Cd, As, Pb, Zn, Ni, Cu, Mn, Cr, and Sb, in contaminated soils.The remaining uncertain factors, including the specific soil HM immobilization mechanisms, long-term beneficial effects, and potential environmental risks associated with BC application are analyzed.Future research must be conducted to ensure that the management of environmental pollution is in accord with ecological sustainability and adaptation of the black gold biotechnology on a commercial basis for immobilization of HMs in contaminated soils. 展开更多
关键词 additives environmental pollution FEEDSTOCK IMMOBILIZATION pyrolysis temperature remediation efficacy
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Effect of Ryegrasses on Soil Runoff and Sediment Control 被引量:31
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作者 ZHOU Zheng-Chao SHANGGUAN Zhou-Ping 《Pedosphere》 SCIE CAS CSCD 2008年第1期131-136,共6页
Living plants and plant roots can reduce runoff and soil erosion. Using a rain simulator, a series of soil erosion experiments were conducted to study the influence of living roots and canopies of ryegrasses (Lolium ... Living plants and plant roots can reduce runoff and soil erosion. Using a rain simulator, a series of soil erosion experiments were conducted to study the influence of living roots and canopies of ryegrasses (Lolium perenne L.) during the growing season on sediment yields and runoff of a silt loam soil. The results indicated that during the growing season, decrements in runoff and sediment yields increased with time. Sediment yields (τ^2 = 0.999) and decrements in runoff (τ2 = 0.946) were closely related to the root surface area density. The contributions of roots and canopies of ryegrasses to the reductions in runoff and sediment yields were different. Canopies usually contributed more to the runoff decrement than the roots, whereas roots contributed up to 96% of the decrease in sediment yields in the late stage of the growing season. 展开更多
关键词 CANOPY ROOT RUNOFF RYEGRASS sediment yield
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