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Remediation of Coastal Sediments by Addition of Calcium Nitrate and Presence of Benthos in a Muddy Tidal Flat 被引量:2
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作者 Hiroyuki Harada Kotarou Akagi +1 位作者 Hiroaki Tutioka Atushi Hashimoto 《Journal of Environmental Protection》 2014年第8期703-708,共6页
This study investigated the change in denitrification rate in muddy tidal flats sediment by chemical and biological remediation. Column experiments were conducted to determine the dependence of denitrification rate on... This study investigated the change in denitrification rate in muddy tidal flats sediment by chemical and biological remediation. Column experiments were conducted to determine the dependence of denitrification rate on the redox potential. Filtered seawater was fed continuously to the pipe filled with sediment from the muddy tidal flats. An increase in the redox potential from -198 mV to 21 mV with bioturbation led to increases in the denitrification rate from 24.2 mg/m2/day to 29.8 mg/m2/day. The increase in denitrification was explained by the acceleration of mass transfer in the sediment. Redox-potential increased from -400 mV to -200 mV by the addition of 10 g calcium nitrate, acid volatile sulfide was below the detection limit to 20 cm depth, and denitrification rate was increased from 21.3 mg/m2/day to 36.4 mg/m2/day. It is considered that the increased nitrogen concentration led to an increase in microbial activity. 展开更多
关键词 Redox Potential MUDDY TIDAL Sediment DENITRIFICATION BIOTURBATION calcium nitrate
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The impact of foliar application of calcium nitrate fertilizer on the yield,quality,and post harvest life of two varieties of roses(Rosa hybrida L.)in a soilless cultivation system
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作者 Saeed Khosravi Ali Tehranifar +2 位作者 Yahya Selahvarzi Amir Hossein Khoshgoftarmanesh Leyla Cheheltanan 《植物营养与肥料学报》 CAS CSCD 北大核心 2024年第12期2392-2402,共11页
【Objectives】Rose(Rosa hybrida L.)is a beautiful and widely cultivated flowering plant around the world whose quality is of great commercial importance.The objective of this study was to investigate the impact of fol... 【Objectives】Rose(Rosa hybrida L.)is a beautiful and widely cultivated flowering plant around the world whose quality is of great commercial importance.The objective of this study was to investigate the impact of foliar application of calcium nitrate on the quality and postharvest life of two rose varieties(cvs.Samurai,and Jumilia)in a soilless culture system.【Methods】The research used a hydroponic culture method,the roses plants were grown in Hoagland nutrient solution containing 50%less Ca for a total span of 4 months.One month was dedicated to plant acclimatization,and 3 months for spray treatment.Two rose varieties(Rosa hybrida L.),cvs.Samurai and Jumilia plants were used as test materials and planted in pots containing 100%perlite(3-5 mm).After one month of culture,160 mg/kg CaNO3 solution was sprayed,and each treatment corresponded to the first,second,and third harvests,respectively.The plant and flower growth indicators and flower vase life were investigated after each harvesting immediately.【Results】A positive impact of foliar-applied Ca on stem characteristics,pedicel dimensions,corolla size,flower attributes,and vase life was found.Furthermore,a general trend was observed,wherein an increase in the number of harvesting stages led to improved traits.Notably,Jumilia rose consistently exhibited lower values for all studied traits,except for flower vase life,in comparison to the Samurai rose.While there were no significant differences in length values between Samurai and Jumilia roses due to calcium foliar application across the three harvesting stages.Duncan’s grouping revealed a specific effect on Jumilia roses during the third harvest stage.Calcium fertilizer significantly increased photosynthesis rates of of rose leaves in the calcium treatments compared with the control treatment.【Conclusions】Foliar spraying of calcium nitrate is an effective measure to promote the growth of roses and improve the yield,quality and bottle life of fresh cut flowers. 展开更多
关键词 calcium fertilizer foliar application vase life ROSE soilless culture
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Psoriasis treatment: Unconventional and non-standard modalities in the era of biologics 被引量:1
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作者 Vikram K Mahajan 《World Journal of Dermatology》 2016年第1期17-51,共35页
Psoriasis is a potentially debilitating inflammatory dermatosis affecting 0.2%-4.8% of the population worldwide causing a significant occupational, personal or psychosocial morbidity to these patients for life. The ba... Psoriasis is a potentially debilitating inflammatory dermatosis affecting 0.2%-4.8% of the population worldwide causing a significant occupational, personal or psychosocial morbidity to these patients for life. The basic aim of psoriasis therapy is to control the disease to maximum possible extent and improve the patient's quality of life. Management of triggers for flareups, lifestyle modifications, and dietary supplements are often recommended. Intermittent or rotational therapy with frequent alterations in treatment options is usually needed to reduce toxicity of anti-psoriatic drugs in the absence of safer alternatives. Currently, several biological agents categorized as either T-cell targeted(e.g., Alefacept, Efalizumab) or cytokine modulating(e.g., Adalimumab, Infliximab, Etanercept) are available for treating severe psoriasis. However, their high cost is often precluding for most patients. The usefulness of systemic(methotrexate, cyclosporine, acitretin or several other therapeutic agents) or topical(tar, anthralin, corticosteroids or calcipotriol ointments, phototherapy with or without psoralens) therapies has been well established for the management of psoriasis. The literature is also replete with benefits of less used non-standard and unconventional treatment modalities(hydroxycarbamide, azathioprine, leflunomide, mycophenolate mofetil, isotretinoin, fumarates, topical calcineurin inhibitors, peroxisome proliferator-activated receptors agonists, statins, sulfasalazine, pentoxifylline, colchicine, grenz ray therapy, excimer laser, climatotherapy and balneophototherapy, peritoneal dialysis, tonsillectomy, ichthyotherapy, etc.). These can be used alternatively to treat psoriasis patients who have mild/minimal lesions, are intolerant to conventional drugs, have developed side effects or achieved recommended cumulative dose, where comorbidities pose unusual therapeutic challenges, or may be as intermittent, rotational or combination treatment alternatives. 展开更多
关键词 Acetretin Azathioprine Balneophototherapy Calcineurin inhibitors CALCIPOTRIOL calcium dobesilate Climatotherapy Colchicine Cyclosporine DAPSONE Excimer laser Fumarates Grenz ray therapy Hydroxycarbamide Ichthyotherapy ISOTRETINOIN Leflunamide Methotrexate MYCOPHENOLATE mofetil Pentoxifylline Peritoneal dialysis Phototherpy Plaque PSORIASIS Peroxisome proliferator-activated receptors agonists Statins SULFASALAZINE Tonsillectomy
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Effects of Calcium Nitrate Levels and Soaking Durations on Cocopeat Nutrient Content
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作者 Sheku N. Gbollie Samuel M. Mwonga Anthony M. Kibe 《Journal of Agricultural Chemistry and Environment》 2021年第3期372-388,共17页
Cocopeat, a by-product of the coconut (<em>Cocos nucifera </em>L.), is an important soilless media that contains high potassium (K), sodium (Na), and electrical conductivity (EC) depending on its source. M... Cocopeat, a by-product of the coconut (<em>Cocos nucifera </em>L.), is an important soilless media that contains high potassium (K), sodium (Na), and electrical conductivity (EC) depending on its source. Methods for extracting these elements and thus lowering EC are yet to be standardized. This study was therefore carried out to investigate two extraction methods of these elements in cocopeat. A greenhouse pot experiment was carried out at the Climate and Water Smart Agriculture Centre of Egerton University, Kenya. It was laid out in a 5 × 4 factorial completely randomized design. Five soaking durations (12, 24, 36, 48, and 72 hours) and four calcium nitrate (Ca(NO<sub>3</sub>)<sub>2</sub>) levels (0, 60, 100, and 150 g) were used. The experiment was done in two folds: the leachate and treated cocopeat examination for their chemical properties. The General Linear Model procedures were used for Analysis of Variance at (P ≤ 0.05). The results showed that the addition of Ca(NO<sub>3</sub>)<sub>2</sub> 100 g extracted significantly more K and Na in the leachate than Ca(NO<sub>3</sub>)<sub>2</sub> 0.0 g and 60 g. The EC levels in the leachate increased with the application levels of Ca(NO<sub>3</sub>)<sub>2</sub> while the pH levels were reducing. In the treated cocopeat, Ca(NO<sub>3</sub>)<sub>2</sub> 100 g and soaking duration 36 hours significantly reduced K and Na and sufficiently supplemented Ca and N. Irrespective of Ca(NO<sub>3</sub>)<sub>2</sub> and soaking durations, after the cocopeat is washed, the EC and pH values fall within their suitable ranges. There was a strong negative correlation between Ca and Na, Ca and K, and between Na and EC. Also, strong positive correlation between Ca and N and Ca and EC. Effective supplementation of Ca and N, and optimal reduction of K and Na by 78.44% and 92%, respectively can be achieved with 100 g of Ca(NO<sub>3</sub>)<sub>2</sub> 1.5 kg<sup>-1</sup> of cocopeat in 15 liters of water with a soaking duration of 36 hours. 展开更多
关键词 calcium nitrate Cocopeat LEACHATE POTASSIUM SOAKING
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Potassium and calcium channels in different nerve cells act as therapeutic targets in neurological disorders
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作者 Qing Qiu Mengting Yang +2 位作者 Danfeng Gong Haiying Liang Tingting Chen 《Neural Regeneration Research》 SCIE CAS 2025年第5期1258-1276,共19页
The central nervous system, information integration center of the body, is mainly composed of neurons and glial cells. The neuron is one of the most basic and important structural and functional units of the central n... The central nervous system, information integration center of the body, is mainly composed of neurons and glial cells. The neuron is one of the most basic and important structural and functional units of the central nervous system, with sensory stimulation and excitation conduction functions. Astrocytes and microglia belong to the glial cell family, which is the main source of cytokines and represents the main defense system of the central nervous system. Nerve cells undergo neurotransmission or gliotransmission, which regulates neuronal activity via the ion channels, receptors, or transporters expressed on nerve cell membranes. Ion channels, composed of large transmembrane proteins, play crucial roles in maintaining nerve cell homeostasis. These channels are also important for control of the membrane potential and in the secretion of neurotransmitters. A variety of cellular functions and life activities, including functional regulation of the central nervous system, the generation and conduction of nerve excitation, the occurrence of receptor potential, heart pulsation, smooth muscle peristalsis, skeletal muscle contraction, and hormone secretion, are closely related to ion channels associated with passive transmembrane transport. Two types of ion channels in the central nervous system, potassium channels and calcium channels, are closely related to various neurological disorders, including Alzheimer's disease, Parkinson's disease, and epilepsy. Accordingly, various drugs that can affect these ion channels have been explored deeply to provide new directions for the treatment of these neurological disorders. In this review, we focus on the functions of potassium and calcium ion channels in different nerve cells and their involvement in neurological disorders such as Parkinson's disease, Alzheimer's disease, depression, epilepsy, autism, and rare disorders. We also describe several clinical drugs that target potassium or calcium channels in nerve cells and could be used to treat these disorders. We concluded that there are few clinical drugs that can improve the pathology these diseases by acting on potassium or calcium ions. Although a few novel ion-channelspecific modulators have been discovered, meaningful therapies have largely not yet been realized. The lack of target-specific drugs, their requirement to cross the blood–brain barrier, and their exact underlying mechanisms all need further attention. This review aims to explain the urgent problems that need research progress and provide comprehensive information aiming to arouse the research community's interest in the development of ion channel-targeting drugs and the identification of new therapeutic targets for that can increase the cure rate of nervous system diseases and reduce the occurrence of adverse reactions in other systems. 展开更多
关键词 ASTROCYTES calcium channels central nervous system extracellular ion concentration MICROGLIA neurological disorders NEURONS potassium channels
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Poly Ethylene Glycols as Efficient Media for the Synthesis of <i>β</i>-Nitro Styrenes from <i>α</i>, <i>β</i>-Unsaturated Carboxylic Acids and Metal Nitrates under Conventional and Non-Conventional Conditions
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作者 Kamatala Chinna Rajanna Kola Ramesh +3 位作者 Soma Ramgopal Somannagari Shylaja Pochampally Giridhar Reddy Pondichery Kuppuswamy Saiprakash 《Green and Sustainable Chemistry》 2011年第4期132-148,共17页
Poly ethylene glycols (PEG-200, 400, 600, 4000 and 6000) supported reactions were conducted with certain α, β-unsaturated acids in presence of metal nitrates under solvent free (solid state) and mineral acid free co... Poly ethylene glycols (PEG-200, 400, 600, 4000 and 6000) supported reactions were conducted with certain α, β-unsaturated acids in presence of metal nitrates under solvent free (solid state) and mineral acid free conditions. The reactants were ground in a mortar with a pestle for about 30 minutes. The aromatic acids underwent nitro decarboxylation and afforded β-nitro styrene derivatives in very good yield while α, β-unsaturated aliphatic carboxylic acids gave corresponding nitro derivatives. Addition of PEG accelerated rate of the reaction enormously. Reaction times substantially decreased from several hours to few minutes followed by highly significant increase in the product yield. Among the several PEGs PEG-300 has been found to be much more effective than other PEGs. 展开更多
关键词 Poly Ethylene Glycols (PEG) Rate Accelerations α β-Unsaturated ACIDS Metal nitrates Solvent Free (Solid State) β-Nitro Styrene DERIVATIVES β-Unsaturated Aliphatic ACIDS NITRO DERIVATIVES
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一维链状2-氧-1(4H)-吡啶乙酸桥联钙配位聚合物[Ca(2-OPA)_2(H_2O)_2]_n的合成、晶体结构及热稳定性研究 被引量:1
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作者 高山 张竹艳 +2 位作者 霍丽华 赵辉 赵经贵 《无机化学学报》 SCIE CAS CSCD 北大核心 2005年第5期771-774,共4页
A novel coordination polymer of [Ca(2-OPA)2(H2O)2]n (2-OPA-=2-oxo-1(4H)-pyridineacetate anion) was synthesized and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. The title complex cr... A novel coordination polymer of [Ca(2-OPA)2(H2O)2]n (2-OPA-=2-oxo-1(4H)-pyridineacetate anion) was synthesized and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. The title complex crystallizes in orthorhombic with space group Pna21, a=0.799 96(16) nm, b=0.823 77(16) nm, c=2.415 3(5) nm, V=1.591 6(6) nm3, Z=4, R=0.030 3, wR=0.070 0. The Ca atom is eight-coordinated by six O atoms of four 2-OPA- ligands and two water molecules, and displays a dodecahedron coordination geometry. Each 2-OPA- ligand bridges two adjacent Ca atoms, forming a infinite chain along the a direction. The Ca...Ca distance is 0.4102 2(8)nm. A two-dimensional supramolecular framework is further constructed by the hydrogen bonds and the weak π-π interactions. The results of TG analysis show the chain structure of the title complex was stable under 297.5 ℃. CCDC: 251669. 展开更多
关键词 analysis complex framework crystal chain direct and space group the The with atom show was CA TG IR π
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依托咪酯对大脑皮质突触体钙离子通道亚型的作用 被引量:3
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作者 张军 庄心良 +1 位作者 李士通 王莹恬 《复旦学报(医学版)》 CAS CSCD 北大核心 2005年第2期216-218,228,共4页
目的 研究依托咪酯对大鼠大脑皮质突触体上不同钙通道的作用 ,探讨其抑制突触体内钙离子浓度升高可能涉及的钙离子通道亚型。方法 利用SD大鼠新鲜分离的大脑皮质突触体为研究对象 ,以KCl作为化学刺激剂去极化 ,采用荧光分光光度法测... 目的 研究依托咪酯对大鼠大脑皮质突触体上不同钙通道的作用 ,探讨其抑制突触体内钙离子浓度升高可能涉及的钙离子通道亚型。方法 利用SD大鼠新鲜分离的大脑皮质突触体为研究对象 ,以KCl作为化学刺激剂去极化 ,采用荧光分光光度法测定依托咪酯 10 0mmol/L单用或与钙通道阻断剂合用的情况下对KCl诱发的突触体内钙离子浓度升高的影响。结果 P/Q型钙通道约占突触体钙内流的 5 0 % ,N型钙通道约占 2 0 % ,而L型钙通道不影响KCl诱发的突触体内钙离子浓度的升高。P/Q型钙通道阻断剂ω agatoxinIVA在单用或及与加入依托咪酯 10 0 μmol/L合用后对钙内流抑制作用没有差异 ,而L或N型钙通道阻断剂在加入依托咪酯后抑制钙内流作用增加。结论 P、N型钙通道在神经末梢去极化后钙离子内流中起主要作用。依托咪酯抑制高浓度KCl刺激引起的突触体内钙离子浓度升高可能与阻断P型 (可能还包括Q型 )钙离子通道有关。 展开更多
关键词 P/Q mol/L N L KCl SD Cl IVA
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香港东北角吉澳群岛入侵植物调查 被引量:10
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作者 严岳鸿 何祖霞 +2 位作者 佘书生 黄忠良 邢福武 《植物研究》 CAS CSCD 北大核心 2005年第2期242-248,共7页
什么样的生态系统容易入侵是入侵生态学关心的核心问题之一。最近,我们对香港东北角吉澳群岛中的鸦洲湾、小鸦洲、鸦洲、拦船排、虎王洲、娥眉洲、往湾洲、吉澳等8个岛屿上的所有外来植物及本土植物的种类、数量和盖度进行了调查,结果表... 什么样的生态系统容易入侵是入侵生态学关心的核心问题之一。最近,我们对香港东北角吉澳群岛中的鸦洲湾、小鸦洲、鸦洲、拦船排、虎王洲、娥眉洲、往湾洲、吉澳等8个岛屿上的所有外来植物及本土植物的种类、数量和盖度进行了调查,结果表明:具有高钙低硅土壤基质的鸦洲、小鸦洲、鸦洲湾等三个小岛上分布有大量外来入侵植物的种类和数量,而具有高硅低钙土壤基质的拦船排、虎王洲、娥眉洲、往湾洲等岛屿上外来植物的种类和数量稀少,吉澳岛虽然外来植物的种类多,但外来植物的个体数量少。分析说明:钙离子可能是影响外来植物的入侵能力或生态系统的可入侵性的关键因子。此外,文章还讨论及介绍了外来植物在石灰岩生境、盐碱地、海岸沙滩、温带广布的各种钙土、地中海气候影响下形成的干旱土等钙离子丰富的生态系统中入侵情况。 展开更多
关键词 屿
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燃煤固体产物中含钙矿物的迁移与多相反应 被引量:23
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作者 刘豪 邱建荣 +4 位作者 熊全军 孔凡海 张小平 王泉海 肖贤云 《中国电机工程学报》 EI CSCD 北大核心 2005年第11期72-78,共7页
燃煤灰渣中含钙矿物的组成和多相反应与灰渣活性密切相关。该文对SBF试验台上煤粉与添加剂混烧后的灰样进行XRD分析,并采用F*A*C*T软件包对煤和添加剂组成的多组分系统进行热力学计算,探讨了不同条件下灰渣中含钙矿物的组成特性。结果表... 燃煤灰渣中含钙矿物的组成和多相反应与灰渣活性密切相关。该文对SBF试验台上煤粉与添加剂混烧后的灰样进行XRD分析,并采用F*A*C*T软件包对煤和添加剂组成的多组分系统进行热力学计算,探讨了不同条件下灰渣中含钙矿物的组成特性。结果表明,燃煤灰渣中含钙矿物主要参与固相反应和固硫反应,固相反应生成的含钙矿物主要包括CaO-SiO2、CaO-Al2O3、CaO-Fe2O3以及CaO-SiO2-Al2O3类矿物。随着CaO含量的增加,灰渣中生成的最主要矿物从莫来石→钙长石→钙黄长石→硅酸二钙过渡。在CaSO4稳定存在的温度范围内,固硫反应比固相反应更易进行;随着温度的升高,CaSO4发生分解或者进一步反应生成硫铝酸钙或硫硅酸钙从而使得钙向硅酸盐矿物迁移。 展开更多
关键词 CASO4 XRD CaO
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微电极法测定水稻叶片液泡中硝酸根离子的再调动 被引量:11
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作者 贾莉君 范晓荣 +2 位作者 尹晓明 曹云 沈其荣 《中国农业科学》 CAS CSCD 北大核心 2005年第7期1379-1385,共7页
作物液泡中硝酸根离子的再调动和再利用与作物氮素高效利用关系密切。利用硝酸根离子微电极技术测定了在外界继续供应和停止供应硝态氮后,不同水稻品种叶片细胞质和液泡中硝酸根离子活度在24h内的变化情况。结果表明:(1)在继续供应硝态... 作物液泡中硝酸根离子的再调动和再利用与作物氮素高效利用关系密切。利用硝酸根离子微电极技术测定了在外界继续供应和停止供应硝态氮后,不同水稻品种叶片细胞质和液泡中硝酸根离子活度在24h内的变化情况。结果表明:(1)在继续供应硝态氮后,水稻植株组织水平的硝酸根离子浓度没有显著的变化,而停止供应硝态氮的植株体内硝酸根离子浓度却有随缺氮时间延长而降低的趋势;(2)水稻叶片细胞质和液泡中硝酸根离子活度存在着明显不同的变化趋势。在停止供应硝态氮的24h内,水稻叶片液泡中的硝酸根离子浓度逐渐降低,而细胞质中的硝酸根离子却维持在一个较低的浓度且基本稳定;(3)扬稻6号液泡中和细胞质中的硝酸根离子活度均高于农垦57,且在停止供应硝态氮的不同时间段,液泡中硝酸根离子的释放速率也均高于农垦57。上述结果表明在受到硝态氮营养胁迫时,水稻先前积累在叶片液泡中的硝酸根离子可以在细胞中进行重新的利用和分配,而且籼稻品种扬稻6号对液泡硝酸根离子再调动能力显然高于粳稻农垦57。 展开更多
关键词 6
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足月新生儿缺氧缺血性脑病患儿脑脊液Na^+、游离Ca^(2+)含量的分析 被引量:2
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作者 陈莎 姚辉 +1 位作者 艾洪武 游上游 《检验医学》 CAS 北大核心 2005年第3期227-229,共3页
目的 探讨足月新生儿缺氧缺血性脑病(HIE)患儿脑脊液钠离子(Na+ )、游离钙离子(Ca2+ )含量的变化与HIE脑损伤程度之间的关系。方法 采用全自动电解质分析仪检测脑脊液Na+、游离Ca2+水平。结果 中、重度HIE组患儿急性期脑脊液Na+、游... 目的 探讨足月新生儿缺氧缺血性脑病(HIE)患儿脑脊液钠离子(Na+ )、游离钙离子(Ca2+ )含量的变化与HIE脑损伤程度之间的关系。方法 采用全自动电解质分析仪检测脑脊液Na+、游离Ca2+水平。结果 中、重度HIE组患儿急性期脑脊液Na+、游离Ca2+含量与对照组比较明显降低(P<0. 05、P<0. 01 ),而轻度HIE组和治疗后恢复期组与对照组比较,脑脊液Na+、游离Ca2+水平虽有降低,但组间差异无显著性(P>0. 01、P>0. 05)。13例中、重度HIE组的急性期患儿治疗后恢复期与治疗前比较,脑脊液及血浆游离Ca2+上升幅度明显高于Na+,其中血浆游离Ca2+上升幅度明显高于脑脊液游离Ca2+。结论 HIE患儿病情越重脑脊液中Na+、游离Ca2+越低,反之病情好转,脑脊液Na+、游离Ca2+有上升趋势。 展开更多
关键词 CA^2%PLUS% NA^%PLUS% CA^2%PLUS% HIE HIE 0.05
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圆叶决明对低温胁迫的生理响应及施Ca^(2+)预防效果的研究 被引量:4
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作者 翁伯琦 江福英 +3 位作者 方金梅 黄毅斌 应朝阳 李延 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第B06期22-27,共6页
对圆叶决明(Chamaecristarotundifolia)牧草CPI86134品系苗期进行15、10、5、0℃的低温胁迫,以25℃胁迫为对照.结果表明:随低温胁迫强度的提高和胁迫时间的延长,植株体内O-·2净产生速率增加;同时植株体内活性氧清除酶SOD、POD、AsA... 对圆叶决明(Chamaecristarotundifolia)牧草CPI86134品系苗期进行15、10、5、0℃的低温胁迫,以25℃胁迫为对照.结果表明:随低温胁迫强度的提高和胁迫时间的延长,植株体内O-·2净产生速率增加;同时植株体内活性氧清除酶SOD、POD、AsAPOD的活性在0~48h胁迫时间之内以较快的速率提高,48h之后提高速率趋缓.其中冷害温度0℃分别胁迫6、12、18、24h后,叶片光合色素含量较对照(25℃)下降21.89%、26.04%、28.16%、29.31%,可溶性蛋白质含量和O-·2净产生速率随胁迫时间延长而提高,活性氧清除酶SOD的活性随胁迫时间延长先上升而后下降.在胁迫前施Ca2+处理可明显降低叶片O-·2净产生速率和电解质渗透率,同时提高了光合色素含量和活性氧清除酶SOD活性,其中以0.5mmol/L浓度的CaCl2处理效果为最佳,说明Ca2+对低温胁迫下圆叶决明的膜结构起有效的保护作用. 展开更多
关键词 Ca^2%PLUS% O2^- SOD CaCl2 POD ASA
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骨代谢生化指标临床应用专家共识(2020) 被引量:192
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作者 张萌萌 张秀珍 +30 位作者 邓伟民 张智海 徐辉 葛继荣 王永福 黄宏兴 史晓林 张东伟 毛未贤 马倩倩 高远 杨茂伟 郭郡浩 张红红 张晓梅 印平 赵方 郑洪新 晁爱军 张岩 孔西建 李英华 李毅中 赵国阳 胡玲 董红宇 吴岩 吴涤 邹军 周惠琼 范馨月 《中国骨质疏松杂志》 CAS CSCD 北大核心 2020年第6期781-796,共16页
骨代谢生化指标包括钙磷代谢调节指标、骨形成标志物、骨吸收标志物、激素与细胞因子。骨代谢生化指标分别来源于骨、软骨、软组织、皮肤、肝、肾、小肠、血液及内分泌腺体等,是由成骨细胞或破骨细胞分泌的酶和激素,以及骨基质的胶原蛋... 骨代谢生化指标包括钙磷代谢调节指标、骨形成标志物、骨吸收标志物、激素与细胞因子。骨代谢生化指标分别来源于骨、软骨、软组织、皮肤、肝、肾、小肠、血液及内分泌腺体等,是由成骨细胞或破骨细胞分泌的酶和激素,以及骨基质的胶原蛋白或非胶原蛋白代谢产物。骨代谢生化指标可及时反映骨转换状态,灵敏度高、特异性强,用于骨质疏松诊断分型、预测骨折风险、抗骨质疏松治疗疗效评价,以及代谢性骨病的诊断与鉴别诊断。并且在骨质疏松流行病学、发病机制、骨质疏松药物的研究方面具有重要的临床意义。本文对《骨代谢生化指标临床应用专家共识(2019)》进行了修订,共有41处修改,保留了经典文献,删减了部分内容,增加了近三年的文献,收集整理了骨代谢指标实验检测参考范围。 展开更多
关键词 D3 25-D3 1 25-D3 IC- IN- IC- IN- 尿 尿 -1 -6 β
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不同钙磷水平对0~4周龄五龙鹅生产性能及血浆和胫骨生化指标的影响 被引量:2
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作者 李文立 王宝维 +1 位作者 刘光磊 林英庭 《动物营养学报》 CAS CSCD 北大核心 2005年第1期60-60,共1页
试验选用1日龄健康五龙鹅雏,研究了饲粮中不同钙磷水平对0~4周龄五龙鹅生产性能、血浆钙磷含量和碱性磷酸酶(AKP)活性以及胫骨灰分及钙磷含量的影响。试验采用4×2二因子设计,饲粮钙水平设计为0.65%、0.75%、0.85%和0.95%,非植酸磷... 试验选用1日龄健康五龙鹅雏,研究了饲粮中不同钙磷水平对0~4周龄五龙鹅生产性能、血浆钙磷含量和碱性磷酸酶(AKP)活性以及胫骨灰分及钙磷含量的影响。试验采用4×2二因子设计,饲粮钙水平设计为0.65%、0.75%、0.85%和0.95%,非植酸磷(NPP)水平设计为0.3%和0.4%。结果表明:①本次试验条件下,以五龙鹅最大体增重、采食量及最高饲料利用率为衡量指标,饲料中适宜的钙水平为0.65%,NPP为0.3%。钙磷间的交互作用对体增重、饲料消耗及料重比影响显著,以体增重与饲料消耗为衡量指标,最佳组合为0.65%Ca×0.3%NPP,Ca/NPP比为2.17,以料重比衡量最佳组合为0.65%Ca×0.4%NPP,Ca/NPP比为1.63。②以较高的血钙、血磷含量和较低的血浆AKP活性为衡量指标,饲粮中适宜的钙水平为0.65%,NPP为0.4%。钙磷间的交互作用对血浆钙磷水平及AKP活性影响极显著,以较高的血钙浓度为衡量指标较理想组合为0.65%Ca×0.4%NPP,以较高的血磷含量为衡量指标较理想组合为0.85%Ca×0.4%NPP,以较低的血浆AKP活性为衡量指标较理想组合为0.65%Ca×0.3%NPP。③以较高的胫骨灰分及钙磷含量为衡量指标,饲粮中适宜的钙水平为0.65%,NPP为0.4%。钙磷互作对胫骨灰分及钙磷含量影响极显著,以胫骨粗灰分及磷含量为衡量指标的较佳组合为0.75%Ca×0.4%NPP。 展开更多
关键词 NPP AKP Ca
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丙泊酚对新生和成年大鼠心肌细胞钙离子移动的影响 被引量:5
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作者 张莹 李士通 +1 位作者 庄心良 沈浩 《复旦学报(医学版)》 CAS CSCD 北大核心 2005年第2期189-191,228,共4页
目的 观察不同浓度丙泊酚对氯化钾和咖啡因诱发的新生和成年大鼠心肌细胞钙离子移动的影响 ,探讨其心肌抑制作用的可能机制。方法 用Fluo 3AM钙荧光指示剂染色培养的新生大鼠或急性分离的成年大鼠心肌细胞 ,在激光共聚焦显微镜下动... 目的 观察不同浓度丙泊酚对氯化钾和咖啡因诱发的新生和成年大鼠心肌细胞钙离子移动的影响 ,探讨其心肌抑制作用的可能机制。方法 用Fluo 3AM钙荧光指示剂染色培养的新生大鼠或急性分离的成年大鼠心肌细胞 ,在激光共聚焦显微镜下动态观察使用丙泊酚前及丙泊酚 (5 0 ,2 5 0 μmol/L)预处理后 ,氯化钾和咖啡因诱发的细胞内钙离子浓度的变化。结果 丙泊酚 5 0 μmol/L使氯化钾诱发的新生或成年大鼠心肌细胞内钙荧光强度的峰值下降 ,较对照组有明显差异 (P <0 .0 1 ) ,对新生大鼠心肌细胞的抑制作用较成年大鼠明显。丙泊酚 2 5 0 μmol/L使细胞内钙荧光强度峰值进一步降低。但两种浓度的丙泊酚对咖啡因诱发的两种心肌细胞钙荧光强度的升高均无明显影响 (P >0 .0 5 )。结论 丙泊酚浓度依赖地降低心肌细胞内钙离子浓度 ,与其抑制细胞外钙内流有关 ,它对新生大鼠心肌细胞的抑制作用更强。提示临床上使用丙泊酚作为麻醉剂 ,尤其对小儿麻醉时应有足够重视。 展开更多
关键词 mol/L
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Plasma membrane calcium ATPase proteins as novel regulators of signal transduction pathways 被引量:1
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作者 Mary Louisa Holton Michael Emerson +1 位作者 Ludwig Neyses Angel L Armesilla 《World Journal of Biological Chemistry》 CAS 2010年第6期201-208,共8页
Emerging evidence suggests that plasma membrane calcium ATPases (PMCAs) play a key role as regulators of calcium-triggered signal transduction pathways via interaction with partner proteins. PMCAs regulate these pathw... Emerging evidence suggests that plasma membrane calcium ATPases (PMCAs) play a key role as regulators of calcium-triggered signal transduction pathways via interaction with partner proteins. PMCAs regulate these pathways by targeting specific proteins to cellular sub-domains where the levels of intracellular freecalcium are kept low by the calcium ejection properties of PMCAs. According to this model, PMCAs have been shown to interact functionally with the calcium-sensitive proteins neuronal nitric oxide synthase, calmodulindependent serine protein kinase, calcineurin and endothelial nitric oxidase synthase. Transgenic animals with altered expression of PMCAs are being used to evaluate the physiological significance of these interactions. To date, PMCA interactions with calcium-dependent partner proteins have been demonstrated to play a crucial role in the pathophysiology of the cardiovascular system via regulation of the nitric oxide and calcineurin/nuclear factor of activated T cells pathways. This new evidence suggests that PMCAs play a more sophisticated role than the mere ejection of calcium from the cells, by acting as modulators of signaling transduction pathways. 展开更多
关键词 Plasma membrane calcium ATPASE Signal TRANSDUCTION Regulation NITRIC oxide CALCINEURIN Nuclear factor of activated T cells
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高效液相色谱法测定血浆中左亚叶酸钙的含量 被引量:6
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作者 邓富良 陈本美 +4 位作者 饶均明 周平 邓世林 陈新 余俊龙 《分析化学》 SCIE EI CAS CSCD 北大核心 2005年第7期996-998,共3页
建立了测定血浆中左亚叶酸钙含量的RPHPLC方法。采用DiamonsilC18色谱柱(150mm×4.6mm,5μm),乙腈50mmol/L磷酸氢二钾/磷酸二氢钾缓冲溶液(10∶90,V/V,用磷酸调pH至4.0)为流动相,用前经0.45μm的过滤膜,超声脱气,流速为1.0mL/min,... 建立了测定血浆中左亚叶酸钙含量的RPHPLC方法。采用DiamonsilC18色谱柱(150mm×4.6mm,5μm),乙腈50mmol/L磷酸氢二钾/磷酸二氢钾缓冲溶液(10∶90,V/V,用磷酸调pH至4.0)为流动相,用前经0.45μm的过滤膜,超声脱气,流速为1.0mL/min,紫外检测波长为290nm,柱温为35℃,进样量20μL。该方法最低检出限为0.2ng;线性范围为0.05~10mg/L,方法平均回收率在97.0%以上;日内及日间精密度的相对标准偏差分别小于4%和6%。该方法简单,快速,灵敏度高,重复性好。 展开更多
关键词 HPLC 线 6mm C18 min
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Characterization of LDPE Reinforced with Calcium Carbonate—Fly Ash Hybrid Filler 被引量:1
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作者 Samson Oluropo Adeosun Mohammed Awwalu Usman +1 位作者 Emmanuel Isaac Akpan Winifred Ifeoma Dibie 《Journal of Minerals and Materials Characterization and Engineering》 2014年第4期334-345,共12页
The synergetic effect of calcium carbonate (CC)-fly ash (FA) hybrid filler particles on the mechanical and physical properties of low density polyethylene (LDPE) has been investigated. Low density polyethylene is fill... The synergetic effect of calcium carbonate (CC)-fly ash (FA) hybrid filler particles on the mechanical and physical properties of low density polyethylene (LDPE) has been investigated. Low density polyethylene is filled with varying weight percentages of FA and CC using melt casting. Composites are characterized for mechanical, thermal, microstructural and physical properties. Results show that the flexural strength increases with increases in FA content of the hybrid filler. It is evident from the study that to achieve optimum density a certain combination of both fillers need to be used. The optimum combination of CC and FA for a higher density (1.78 g/cm3) is found to be at 20 wt% FA and 30 wt% CC. An increase of 7.27% in micro-hardness over virgin polyethylene is obtained in composites with 10 wt% FA and 40 wt% CC. The presence of higher amount of CC is seen to be detrimental to the crystallinity of composites. X-ray, FTIR and DSC results show that composite with 45 wt% CC and 5 wt% FA exhibits a typical triclinic polyethylene structure indicating that the composite is amorphous in nature. There was the synergy between FA and CC fillers on flexural strength and crystallinity of composite. However, the fillers show the antagonistic effect on energy at peak and micro-hardness. 展开更多
关键词 LDPE calcium CARBONATE Coal FLY Ash CRYSTALLINITY Melt Flow Index FLEXURAL Strength Micro-Hardness Energy at Peak
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氯化钙与硫酸盐复配处理高泥质煤泥水的试验研究 被引量:5
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作者 李亚峰 郭勇 +1 位作者 陈健 班福忱 《沈阳建筑大学学报(自然科学版)》 EI CAS 2005年第3期238-241,共4页
目的复配一种高效混凝剂取代常用的氯化钙混凝剂,不仅使煤泥水得到有效的处理并满足回用要求,而且减轻Cl-对管道和设备的腐蚀.方法利用氯化钙与硫酸镁、硫酸铁、硫酸铝复配出新的药剂,进行了3种复配药剂处理煤泥水的对比试验,并通过实... 目的复配一种高效混凝剂取代常用的氯化钙混凝剂,不仅使煤泥水得到有效的处理并满足回用要求,而且减轻Cl-对管道和设备的腐蚀.方法利用氯化钙与硫酸镁、硫酸铁、硫酸铝复配出新的药剂,进行了3种复配药剂处理煤泥水的对比试验,并通过实验与理论分析对复配药剂处理煤泥水的作用机理进行研究.结果实验研究结果说明,氯化钙与硫酸镁复配处理煤泥水的效果最好,处理后煤泥水的各项指标均能达到国家排放标准,且能满足洗煤工艺的用水要求.氯化钙与硫酸镁的适宜比例为1∶1.结论实验研究与理论分析结果表明:钙镁复合药剂对煤泥水的混凝机理并不完全符合DLVO理论,它是多方面因素共同作用的结果. 展开更多
关键词 DLVO Cl^-
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