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喷钙对‘黄金梨’钙动态及亚细胞分布的影响
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作者 张泽杰 李冬梅 +6 位作者 周君 文滨滨 宋文亮 肖伟 高东升 陈修德 李玲 《植物生理学报》 CAS CSCD 北大核心 2019年第8期1259-1266,共8页
以‘黄金梨’(Pyrus pyrifolia ‘Whangkeumbae’)为试材,研究幼果期喷0.5%氨基酸钙和0.5%硝酸钙对树体钙含量变化、果实钙组分及亚细胞分布的影响。结果表明,叶片和新梢在果实发育前期对钙的吸收速率较快,喷施氨基酸钙明显提高了果实... 以‘黄金梨’(Pyrus pyrifolia ‘Whangkeumbae’)为试材,研究幼果期喷0.5%氨基酸钙和0.5%硝酸钙对树体钙含量变化、果实钙组分及亚细胞分布的影响。结果表明,叶片和新梢在果实发育前期对钙的吸收速率较快,喷施氨基酸钙明显提高了果实发育期的叶片钙含量,而对新梢和多年生枝影响不显著。果皮和果肉的钙含量在幼果期最高,随着果实生长,总钙含量逐渐下降。与对照相比,喷施氨基酸钙及硝酸钙均可以显著增加果实钙素养分。而且喷钙可以提高梨果肉中各钙组分的含量。通过透射电镜观察,钙处理影响了梨果肉中钙亚细胞分布,显著提高了细胞间质与细胞壁中钙的分布,且细胞中钙均匀分布于液泡膜和细胞膜上。因此,在幼果期喷钙是有效提高‘黄金梨’钙含量的重要措施。 展开更多
关键词 '黄金梨’ 钙动态 亚细胞
响应面法制备小球藻多肽-钙螯合物的制备工艺 预览
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作者 花朋朋 熊煜 +2 位作者 于志颖 刘斌 赵立娜 《农产品加工》 2019年第5期47-52,共6页
为探究小球藻多肽-钙螯合物的较佳制备工艺,以小球藻干粉作为原料,对其进行酶解,获得小球藻多肽,以螯合率为指标,对小球藻多肽与CaCl2的螯合工艺进行了优化,考查了螯合时间、螯合温度、肽钙质量比、底物质量分数和pH值对螯合反应的影响... 为探究小球藻多肽-钙螯合物的较佳制备工艺,以小球藻干粉作为原料,对其进行酶解,获得小球藻多肽,以螯合率为指标,对小球藻多肽与CaCl2的螯合工艺进行了优化,考查了螯合时间、螯合温度、肽钙质量比、底物质量分数和pH值对螯合反应的影响,通过Box-Behnken试验设计与响应面分析,同时建立螯合物制备工艺的二次项数学模型并验证其可靠性,优化后确定为螯合温度50℃,pH值9,肽钙质量比3∶1,底物质量分数5%,螯合时间60 min,最终螯合率可达96.14%。研究为合成新型补钙制剂(多肽-钙螯合物)的开发提供了理论依据,也为小球藻的开发利用提供了一个新的开拓思路。 展开更多
关键词 小球藻多肽 螯合 响应面法 小球藻多肽-钙螯合物
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钙调蛋白激酶Ⅱ的结构及其在神经系统中的作用
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作者 王彤彤 陈治池 +4 位作者 叶鑫 傅维达 陈梦娇 李俊楠 孙臣友 《解剖学报》 CAS CSCD 北大核心 2019年第3期395-399,共5页
钙离子(Ca2+)是通过局部信号获得特异性刺激的关键细胞内信使分子。Ca2+结合蛋白,如钙调蛋白(CaM)及其靶蛋白是Ca 2+依赖性反应信号传导的关键靶点。钙/钙调蛋白依赖性蛋白酶Ⅱ(CaMKⅡ)是一种多聚体酶,它是哺乳动物前脑总蛋白的重要组... 钙离子(Ca2+)是通过局部信号获得特异性刺激的关键细胞内信使分子。Ca2+结合蛋白,如钙调蛋白(CaM)及其靶蛋白是Ca 2+依赖性反应信号传导的关键靶点。钙/钙调蛋白依赖性蛋白酶Ⅱ(CaMKⅡ)是一种多聚体酶,它是哺乳动物前脑总蛋白的重要组成部分,并且是形成突触后致密部的主要成分。近年来国内外研究显示,CaMKⅡ包含α、β、γ和δ4种亚型,其中α和β主要在神经组织中表达,而γ和δ则在全身多种组织均有表达,它们参与特定的突触可塑性和记忆巩固过程,对神经系统的兴奋性及一些神经系统疾病的发生起重要作用。前期也有研究表明CaMKⅡδ在促进神经元存活中起重要作用。本文就CaMKⅡ的结构及其在神经系统中的作用和与相关神经系统疾病的关系作一综述。 展开更多
关键词 钙离子 钙调蛋白 钙调蛋白激酶Ⅱ
Absorption Characteristics of Novel Compound Calcium Carbonate Granules:Effects of Gastric Acid Deficiency and Exogenous Weak Acids 预览
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作者 Hong-dan CHEN Yi-ping CHEN +3 位作者 Rui XIE Qin-yu HU Qi CHENG Ming XIANG 《当代医学科学(英文)》 SCIE CAS 2019年第2期337-342,共6页
Calcium carbonates are commonly administered as supplements for conditions of calcium deficiency.We report here pharmacokinetic characteristics of a novel formulation,calcium carbonate compound granules(CCCGs).forming... Calcium carbonates are commonly administered as supplements for conditions of calcium deficiency.We report here pharmacokinetic characteristics of a novel formulation,calcium carbonate compound granules(CCCGs).forming complexes of calcium carbonate and calcium citrate in water.CCCGs were compared to a kind of commonly?used calcium carbonate preparation(CC)in the market in 5-week-old mice that had been treated with omeprazole,to suppress gastric acid secretion,and in untreated control mice.The results showed that:(1)CCCGs had better water solubility than CC in vitro;(2)In control mice,calcium absorption rates after CCCGs administration were comparable to those after CC administration;(3)Inhibition of gastric acid secretion did not affect calcium absorption after CCCGs,but moderately decreased it after CC;(4)The presence of phytic acid or tannin did not affect calcium absorption rates after CCCGs but did for CC;and(5)In nonnal mice,CCCGs did not inhibit gastric emptying and intestinal propulsion,and did not alter the gastrointestinal honnones.The results suggest that CCCGs may be therapeutically advantageous over more commonly used calcium supplement formulations,particularly for adolescents,because of their stable calcium absorption characteristics and their relatively favorable adverse effect profile. 展开更多
关键词 CALCIUM carbonate gastric ACID inhibition phytic ACID TANNIN CALCIUM absorption
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人RPE细胞通过隧道纳米管传递钙信号的研究进展 预览
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作者 王舒 蔡善君 《遵义医学院学报》 2019年第3期345-349,共5页
Ca^2+信号传导在细胞生理过程中至关重要,Ca^2+是决定细胞命运的主要信号分子,包括细胞分化和细胞死亡。细胞间通讯也是依赖于Ca^2+信号的传导,近年来,报道了一种新型的动物细胞间通讯,它连接单个细胞并选择性的促进远距离细胞与细胞之... Ca^2+信号传导在细胞生理过程中至关重要,Ca^2+是决定细胞命运的主要信号分子,包括细胞分化和细胞死亡。细胞间通讯也是依赖于Ca^2+信号的传导,近年来,报道了一种新型的动物细胞间通讯,它连接单个细胞并选择性的促进远距离细胞与细胞之间的通讯,这些高度敏感的纳米管状结构被称为隧道纳米管(tunneling nanotubes,TNT),人视网膜色素上皮细胞(retinal pigment epithelial,RPE)细胞株Arpe-19具有TNT来交换细胞间的分子信息,并且可以利用Ca^2+显像技术来显示细胞间钙信号通过TNT传递,人RPE细胞系通过隧道纳米管进行通讯,为RPE细胞之间的通讯提供了一种新的途径,因此,未来需要进一步研究细胞间通过隧道纳米管传递钙离子。 展开更多
关键词 钙离子 钙信号 隧道纳米管 人RPE细胞
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同步辐射微束荧光分析技术在兔髌骨-髌腱界面中钙、锌元素分布的应用
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作者 陈洋 陈灿 +1 位作者 陈华斌 吕红斌 《中华实验外科杂志》 CAS CSCD 北大核心 2019年第1期57-59,共3页
目的利用同步辐射微束荧光分析技术(SR-μXRF)表征兔髌骨-髌腱界面(PPTI)中钙、锌元素的含量及分布特点。方法兔PPTI经切片及抛光处理后,于上海光源行SR-μXRF检测,检测后样本行苏木素-伊红(HE)及樊基森(Van-Gieson)染色进行匹配观察。... 目的利用同步辐射微束荧光分析技术(SR-μXRF)表征兔髌骨-髌腱界面(PPTI)中钙、锌元素的含量及分布特点。方法兔PPTI经切片及抛光处理后,于上海光源行SR-μXRF检测,检测后样本行苏木素-伊红(HE)及樊基森(Van-Gieson)染色进行匹配观察。结果组织学染色显示兔PPTI钙化的纤维软骨层厚度为(163.00±42.00) μm;SR-μXRF检测可见兔PPTI中钙含量最大值93 853 cps(位于钙化纤维软骨层与软骨下骨的交界区)是髌腱的(28.00±9.05)倍;锌含量最大值10 100 cps(位于钙化与未钙化纤维软骨层的交界区)是髌腱的(3.20±0.65)倍;钙含量的最大值是锌的(8.70±3.20)倍;钙、锌含量的最大值所处位置相距(135.00±16.00) μm,与组织学染色结果一致(r^2=0.935)。结论SR-μXRF可超微分辨地表征PPTI中微量元素的含量及分布特征. 展开更多
关键词 同步辐射微束荧光分析技术 钙元素 锌元素 骨腱界面
钙离子调节改变与心肌缺血/再灌注损伤
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作者 肖滨 黄小波 《心脏杂志》 CAS 2019年第1期98-102,共5页
心肌细胞钙离子失去稳态调节是多种心脏病变的基础,与缺血/再灌注损伤关系密切。缺血/再灌注引起细胞内外钙离子调节方式发生变化,导致胞浆及线粒体基质钙超载;通过能量依赖性肌纤维过度收缩、钙蛋白酶介导的细胞蛋白水解、线粒体渗透... 心肌细胞钙离子失去稳态调节是多种心脏病变的基础,与缺血/再灌注损伤关系密切。缺血/再灌注引起细胞内外钙离子调节方式发生变化,导致胞浆及线粒体基质钙超载;通过能量依赖性肌纤维过度收缩、钙蛋白酶介导的细胞蛋白水解、线粒体渗透性转换孔的开放、诱导细胞凋亡,以及关闭缝隙连接通道使细胞活动失同步等途径致使心肌结构破坏、功能下降或电生理紊乱。干预细胞钙离子调节不同的环节,纠正或维持钙离子稳态则被证实有助于防止或减轻心肌缺血/再灌注损伤。 展开更多
关键词 钙离子 稳态 钙超载 钙蛋白酶 线粒体渗透性转换孔 心肌 缺血/再灌注损伤
A genetically encoded ratiometric calcium sensor enables quantitative measurement of the local calcium microdomain in the endoplasmic reticulum
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作者 Chen Luo Huiyu Wang +3 位作者 Qi Liu Wenting He Lin Yuan Pingyong Xu 《生物物理学报:英文版》 CSCD 2019年第1期31-42,共12页
The local Ca^2+ release from the heterogeneously distributed endoplasmic reticulum (ER) calcium store has a critical role in calcium homeostasis and cellular function. However;single fluorescent proteinbased ER calciu... The local Ca^2+ release from the heterogeneously distributed endoplasmic reticulum (ER) calcium store has a critical role in calcium homeostasis and cellular function. However;single fluorescent proteinbased ER calcium probes experience challenges in quantifying the ER calcium store in differing live cells, and intensity-based measurements make it difficult to detect local calcium microdomains in the ER. Here, we developed a genetically encoded ratiometric ER calcium indicator [GCEPIA1-SNAPer] that can detect the real-time ER calcium store and local calcium microdomains in live cells. GCEPIA1-SNAPer was located in the lumen of the ER and showed a linear;reversible and rapid response to changes in the ER calcium store. The GCEPIA1-SNAPer probe effectively monitored the depletion of the ER calcium store by TG or starvation treatment, and through 让s use we identified heterogeneously distributed calcium microdomains in the ER which were correlated w让h the distribution of STIM1 clusters upon ER calcium store depletion. Lastly, GCEPIA1-SNAPer can be used to detect the ER calcium store by high-throughput flow cytometry and confers the ability to study the function of calcium microdomains of the ER. 展开更多
关键词 RATIOMETRIC CALCIUM sensor LOCAL CALCIUM microdomain Endoplasmic reticulum
Application of phosphate-containing materials affects bioavailability of rare earth elements and bacterial community in soils
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作者 JIN ShuLan HU ZhongJun +3 位作者 MAN BaiYing PAN HuaHua KONG Xiao JIN DeCai 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第9期1616-1627,共12页
The exploitation and smelting of rare earths can cause serious pollution to the farmland around the mining area. The rare earth elements(REEs) are absorbed by crops and enter the human body through the food chain, whi... The exploitation and smelting of rare earths can cause serious pollution to the farmland around the mining area. The rare earth elements(REEs) are absorbed by crops and enter the human body through the food chain, which threatens people’s health. The effects of four phosphorus-containing materials-calcium superphosphate(SSP), phosphate rock(PR), calcium magnesium phosphate(CMP) and bone charcoal(BC) on rice growth and bacterial community structure in REE mining area of Xinfeng County were studied by pot experiment. The soil solution was collected during rice transplanting and harvest periods respectively, the rice and soil samples were collected and sequenced. The concentrations of water-soluble REEs were measured by inductively coupled plasma mass spectrometry(ICP-MS), and bacteria in soil was deeply sequenced by the Illumina Miseq sequencing platform. PR, CMP and BC promoted the growth of rice, improved the biomass of rice roots, shoots and grains, and significantly reduced absorption and accumulation of REEs in rice roots, shoots and grains. SSP treatment reduced the pH value of soil, significantly improved the concentration of REE solution in soil and improved biomass of rice roots, shoots and grains,and significantly improved the concentration of REEs in grain. The effects of phosphorus-containing materials on the absorption and accumulation of 15 REEs in rice roots, shoots and grains were very different, and significantly influenced the soil bacterial community. SSP reduced richness and diversity of bacteria. CMP improved the diversity of soil bacteria, but reduced their richness. PR and BC treatment improved the richness and diversity of soil bacteria, and significantly increased the abundance of Bacillus. The results showed that adding PR, CMP and BC to soil in the REE mining area of Xinfeng can improve food security and eco-environmental quality, and hence, are potential restorative materials;SSP is not recommended for use in acidic soils. 展开更多
关键词 CALCIUM SUPERPHOSPHATE PHOSPHATE rock CALCIUM magnesium phosphorus bone charcoal rare earth elements rice bacterial community
In situ Raman imaging of high-temperature solid-state reactions in the CaSO4-SiO2 system 预览
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作者 Nadine Bohme Kerstin Hauke +1 位作者 Manuela Neuroth Thorsten Geisler 《国际煤炭科学技术学报:英文版》 2019年第2期247-259,共13页
The deposition of mineral phases on the heat transfer surfaces of brown coal power plants may have a negative effect on power plant boilers. The paragenesis of these deposits contains information about the actual temp... The deposition of mineral phases on the heat transfer surfaces of brown coal power plants may have a negative effect on power plant boilers. The paragenesis of these deposits contains information about the actual temperature prevailed during the combustion of lignite, if the temperature-dependences of distinct mineral transformations or reactions are known. Here, we report results of a sintering study (to ?1100℃) with samples containing anhydrite, quartz, and gehlenite, which are typical components of Rhenish lignite ashes. Thermal decompositions and solid-state reactions were analyzed (1) in situ and (2) both in situ and after quenching using confocal hyperspectral Raman imaging. This novel application of confocal Raman spectroscopy provides temperature-and time-resolved, 2-dimensional information about sintering processes with a micrometer-scale resolution. In the course of the sintering experiments with anhydrite and quartz with a weight ratio of 2:1 both polymorphs wollastonite and pseudowollastonite were identified in situ at about 920 and 1000℃, respectively. The formation of pseudowollastonite was thus observed about 120℃ below the phase transition temperature, demonstrating that it can form metastably. In addition,α′L-Ca2SiO4 was identified at about 1100℃. In samples containing equal weight fractions of anhydrite and quartz that were quenched after firing for 9h at about 1100℃,β-Ca2SiO4 (larnite) crystallized as rims around anhydrite grains and in direct contact to wollastonite. We furthermore observed that, depending on the ratio between quartz and anhydrite, wollastonite replaced quartz grains between 920 and 1100℃., i.e., the higher the quartz content, the lower the formation temperature of wollastonite. 展开更多
关键词 ASH deposition CALCIUM SILICATE CALCIUM SULFATE High-temperature RAMAN imaging
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EDTA络合滴定法快速测定矿石中钙、镁 预览
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作者 韩晓 《中国无机分析化学》 CAS 2019年第2期54-57,共4页
试样用盐酸、硝酸、氢氟酸、高氯酸分解,在pH值为6~9时,经六次甲基四胺-铜试剂分离铁、铝、镍、钴、铅、锌、铜、镉、锰等干扰元素后,在pH=10的氨水和氯化铵缓冲溶液中,以酸性铬蓝K-萘酚绿B为指示剂,用EDTA络合滴定法测定钙镁合量;另在... 试样用盐酸、硝酸、氢氟酸、高氯酸分解,在pH值为6~9时,经六次甲基四胺-铜试剂分离铁、铝、镍、钴、铅、锌、铜、镉、锰等干扰元素后,在pH=10的氨水和氯化铵缓冲溶液中,以酸性铬蓝K-萘酚绿B为指示剂,用EDTA络合滴定法测定钙镁合量;另在氢氧化钾溶液中,用钙试剂为指示剂,以EDTA络合滴定法测定钙量,从而计算镁的含量。当样品钙高镁低或者镁高钙低时,低含量的镁量或钙量(<5%)可用电感耦合等离子体原子发射光谱(ICP-AES)法准确测定,使结果更准确。实验中对三个标准样品中的钙和镁进行多次测定,结果与认定值相符,相对标准偏差在0.69%~1.3%(n=7),加标回收率在99%~102%。方法实用性强,已经成功应用于各类矿石中钙镁的检测。 展开更多
关键词 容量法 ICP-AES 矿石
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PSGL-1 Ligation-Induced Activation of Mac-1 under Flows
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作者 Xiaoxi Sun Yuping Pan +1 位作者 Ying Fang Jianhua Wu 《医用生物力学》 CAS CSCD 北大核心 2019年第A01期90-91,共2页
Inflammation and thrombosis usually occur together in many diseases,such as cardiovascular disease(CVD)and stroke,which remain to be the mostdetrimental human health killers.The crucial relevant cellular and molecular... Inflammation and thrombosis usually occur together in many diseases,such as cardiovascular disease(CVD)and stroke,which remain to be the mostdetrimental human health killers.The crucial relevant cellular and molecular events include platelet-leukocyte interaction,platelet P-selectin secretion of activated platelet and activation of leukocyte integrin Mac-1(also known asαMβ2 or CD11b/CD18),which has binding site of platelet receptor glycoprotein lbα(GPlboα). Circulating leukocytes tethered to,rolled on and firmly adhered at the activated platelets on vascular wall,through interaction of platelet P-selectin with leukocyte P-selectin glycoprotein ligand-1(PSGL-1)and Mac-1 with GPlbα.We assume that there is a rapid signaling pathway in PSGL-1 ligation-induced activation of Mac-1,for forming a stable gap junction intracellular communication between platelet and leukocyte.To test this assumption,we observed the tethering events and calcium bursting of neutrophils on immobilized P-selectin only or plus GPlbαwith use of the parallel plate flow chamber(PPFC)technique and intracellular calcium ion detector Fluo-4 AM at various wall shear stresses,and examined the dynamic force spectrum for interaction of Mac-1 plus Mn2+and GPlbαby single-molecule atomic force microscopy(AFM).In the PPFC experiments,the intracellular calcium flux of firmly adhered neutrophils on immobilized P-selectin only or plus GPlbαwas observed in real timeby fluorescence microscopy,and the tether events of neutrophils was recorded by an inverted microscope and a high speed CMOS acquisition system in 1280 pixels×1024 pixels at 100 frames per second(fps). Captured images were analyzed by Image Pro Plus.Our results indicated that force triggered,enhanced and quickened the cytoplasmic calcium bursting of neutrophils.Calcium bursting may be induced first by interaction of the activated neutrophil Integrin Mac-1 and GPlbα,but not by P-selectin ligation to its ligand PSGL-1.Being triggered and speeded up by wall shear stress,the P-selectin-induced a 展开更多
关键词 INTEGRIN activation Mac-1-GPIbα interaction cellular calcium BURSTING force-chemical coupling
锂、钠、钾、镁、钙、氯复合电解质冰冻人血清国家标准品的研制和性能评价 预览
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作者 于婷 沈敏 +1 位作者 曲守方 黄杰 《检验医学》 CAS 2019年第5期457-462,共6页
目的研制锂、钠、钾、镁、钙、氯复合电解质冰冻人血清国家标准品,并评价其性能,促进锂、钠、钾、镁、钙、氯电解质测定的标准化。方法收集含不同浓度锂、钠、钾、镁、钙、氯离子的无溶血、脂血和黄疸血清,经多重过滤、除菌后分装,制备... 目的研制锂、钠、钾、镁、钙、氯复合电解质冰冻人血清国家标准品,并评价其性能,促进锂、钠、钾、镁、钙、氯电解质测定的标准化。方法收集含不同浓度锂、钠、钾、镁、钙、氯离子的无溶血、脂血和黄疸血清,经多重过滤、除菌后分装,制备成3个水平的候选品,-70℃保存。以钾离子作为均匀性评价的特性量,采用单因素方差分析评价候选品的均匀性。以钾、钠、氯离子作为稳定性评价的特性量,采用线性回归分析评价候选品的稳定性。采用参考方法或经验证的方法定值,并计算不确定度。评估候选品、新鲜血清样本在参考方法或经验证的方法与4个常规检测系统间的互通性。结果3个水平侯选品中,钾离子的均匀性检验F值分别为1.6301、1.4986和1.0208,均<F0.05;钾、钠、氯离子在2~8℃、20~25℃和-20℃条件下,均至少可稳定30d。3个水平侯选品中,锂离子定值结果分别为(0.649±0.022)、(1.195±0.032)、(1.334±0.008)mmol/L(k=2),钠离子定值结果分别为(120.057±2.206)、(142.030±1.521)、(158.228±1.293)mmol/L(k=2),钾离子定值结果分别为(5.042±0.143)、(5.739±0.106)、(6.158±0.094)mmol/L(k=2),镁离子定值结果分别为(0.732±0.021)、(0.857±0.026)、(1.144±0.026)mmol/L(k=2),钙离子定值结果分别为(2.014±0.078)、(2.348±0.056)、(3.070±0.024)mmol/L(k=2),氯离子定值结果分别为(90.814±2.005)、(108.875±0.908)、(128.156±1.453)mmol/L(k=2)。钠、钾、镁、钙和氯离子3个水平侯选品浓度均在新鲜血清样本的95%可信区间内,互通性良好。结论制备的锂、钠、钾、镁、钙、氯复合电解质冰冻人血清国家标准品候选品均匀性、稳定性好,钠、钾、镁、钙和氯离子侯选品互通性良好,定值准确可靠,可作为国家标准品使用。 展开更多
关键词 冰冻人血清 国家标准品
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硅钙对日光温室黄瓜光合作用及产量和品质的影响
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作者 翟江 高原 +4 位作者 张晓伟 韩鲁杰 毕焕改 李清明 艾希珍 《园艺学报》 CAS CSCD 北大核心 2019年第4期701-713,共13页
为了探明硅和钙对黄瓜生长发育的调控机理,以’津优35号’黄瓜(Cucumis sativus L.’Jinyou35’)为试材,用盆栽基质培养方法,以不添加硅、钙为对照,研究单施硅(Si)、单施钙(Ca)和硅钙配施(Si+Ca)对黄瓜光合特性、产量及品质的影响。结... 为了探明硅和钙对黄瓜生长发育的调控机理,以’津优35号’黄瓜(Cucumis sativus L.’Jinyou35’)为试材,用盆栽基质培养方法,以不添加硅、钙为对照,研究单施硅(Si)、单施钙(Ca)和硅钙配施(Si+Ca)对黄瓜光合特性、产量及品质的影响。结果表明:Si、Ca和Si+Ca处理均能提高黄瓜叶片的净光合速率(Pn);Si处理的气孔导度(Gs)和蒸腾速率(Tr)显著小于对照,Ca处理显著大于对照,Si+Ca处理与对照差异不显著;Ca和Si+Ca处理可使胞间CO2浓度(Ci)明显升高,而Si处理与对照差异不显著。与对照相比,Si、Ca和Si+Ca处理Rubisco活化酶(RCA)、果糖-1,6-二磷酸酶(FBPase)、景天庚酮糖-1,7-二磷酸酶(SBPase)、果糖-1,6-二磷酸醛缩酶(FBA)和转酮醇酶(TK)活性显著升高;Si+Ca处理的核酮糖-1,5-二磷酸羧化酶(RuBPCase)活性也明显升高,Si、Ca处理无显著变化。Si、Ca和Si+Ca处理的Rubisco大亚基(rbcL)和小亚基(rbcS)、RCA、FBP、SBP、FBA和TK mRNA相对表达量均显著大于对照。Si、Ca和Si+Ca处理叶片的暗适应下PSⅡ最大光化学效率(Fv/Fm)无显著变化,但光下PSⅡ实际光化学效率(ΦPSⅡ)均明显高于对照。Si、Ca和Si+Ca均可促进黄瓜植株生长,产量分别比对照增加11.75%、14.23%和21.28%,黄瓜果实的可溶性糖、蛋白质、游离氨基酸、维生素C含量显著升高,亚硝酸盐和单宁含量明显降低。可见,Si、Ca和Si+Ca可提高黄瓜叶片的Calvin循环关键酶活性与基因表达,增强光合碳同化能力,提高光化学效率,从而促进植株生长,产量和品质显著提高。3个处理相比,Si+Ca处理的光合能力最强,生长量最大,提质增产效果最佳。 展开更多
关键词 黄瓜 光合酶 产量 品质
钙水平对无限生长型番茄钙吸收利用及果实品质和产量的影响 预览
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作者 吴一群 林琼 +1 位作者 陈子聪 林静芬 《水土保持学报》 CSCD 北大核心 2019年第5期185-189,共5页
利用基质栽培水肥一体化技术,设计不同钙素营养供给水平(0,1,3,6 mmol/L),研究钙对无限生长型番茄钙吸收利用及果实品质和产量的影响。结果表明:钙在番茄植物各部位中的分布极不均匀,且同一部位不同时期钙含量差异也很大,植物体内钙的... 利用基质栽培水肥一体化技术,设计不同钙素营养供给水平(0,1,3,6 mmol/L),研究钙对无限生长型番茄钙吸收利用及果实品质和产量的影响。结果表明:钙在番茄植物各部位中的分布极不均匀,且同一部位不同时期钙含量差异也很大,植物体内钙的分布和变化受钙素营养水平和气温的影响;随着钙水平的提高,番茄果实钙含量不断增加,缺钙将降低果实的产量和品质,虽然钙与K、Mg、P、N元素之间存在拮抗作用,但是高钙不会造成果实产量和品质的下降;高温会诱导植株缺钙症状及果实脐腐病的出现,严重影响番茄的产量和品质,高钙处理对高温胁迫具有一定的缓解作用。 展开更多
关键词 番茄 无限生长型 吸收利用 胁迫
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维生素D钙和扩张性心肌病与猝死
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作者 张亚男 张会丰 《中国实用儿科杂志》 CSCD 北大核心 2019年第7期565-568,共4页
低钙性心肌病可以引起突发性充血性心力衰竭、心源性休克或猝死。低血钙性心肌病是充血性心力衰竭的原因之一。对婴幼儿阶段的扩张性心肌病做出诊断时,都要警惕低钙性心肌病。低血钙性心肌病,低血钙是生化特征,心肌病是病理变化。维生素... 低钙性心肌病可以引起突发性充血性心力衰竭、心源性休克或猝死。低血钙性心肌病是充血性心力衰竭的原因之一。对婴幼儿阶段的扩张性心肌病做出诊断时,都要警惕低钙性心肌病。低血钙性心肌病,低血钙是生化特征,心肌病是病理变化。维生素D缺乏是心肌病的初始原因。低血钙性心肌病发病基础是维生素D或钙缺乏。低血钙性心肌病对维生素D和钙补充呈现的良好反应。 展开更多
关键词 维生素D缺乏 心肌病 猝死
Investigation of the medium calcium based non-burnt brick made by red mudand fly ash:durability and hydration characteristics 预览
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作者 Ying-tang Xu Bo Yang +4 位作者 Xiao-ming Liu Shuai Gao Dong-sheng Li Emile Mukiza Hua-jian Li 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第8期983-991,共9页
Red mud is a type of highly alkaline waste residue produced in the process of alumina smelting by the Bayer process.Based on the idea of medium calcium content,solid wastes such as red mud and fly ash were used to pre... Red mud is a type of highly alkaline waste residue produced in the process of alumina smelting by the Bayer process.Based on the idea of medium calcium content,solid wastes such as red mud and fly ash were used to prepare non-burnt bricks;and the mass ratio of CaO/SiO2 was selected in the range of 0.88–1.42.Mechanical properties and durability were investigated with a compressive strength test.X-ray diffractometry(XRD),scanning electron microscope(SEM),and Fourier transform infrared spectroscopy(FTIR)techniques were used to characterize the hydration characteristic.The environmental performance was analyzed by Inductively Coupled Plasma Mass Spectrometry(ICP).The results indicated that the mechanical properties and the durability were optimal when the mass ratio of CaO/SiO2 was 1.23.The hydration products were mostly C–S–H gel,ettringite,Na4Ca(Si10All6)O32·12H2O and Ca3Al2(SiO4)(OH)8.They were responsible for the strength development,and the CaO/SiO2 mass ratio of 1.23 had the best polymerized structure.The results of an environmental performance test showed that the heavy metals in the raw materials were well-solidified in the brick.Therefore,this paper provides an effective solution for use of solid wastes in building material. 展开更多
关键词 MEDIUM CALCIUM content red MUD fly ash non-burnt BRICK
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钙尔奇D联合重组人生长激素对特发性矮身材儿童骨代谢及血清IGF-1、25-(OH)D水平变化的影响研究
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作者 唐秀平 李玲 闫保瑞 《中国儿童保健杂志》 CAS 2019年第7期729-732,共4页
目的探讨钙尔奇D辅助重组人生长激素(rhGH)治疗特发性矮身材(ISS)儿童的疗效及对骨代谢指标、胰岛素样生长因子-1(IGF-1)、25羟维生素D[25-(OH)D]水平的影响。方法选取2015年1月-2017年6月本院收治的90例ISS患儿(ISS组),随机分为观察组... 目的探讨钙尔奇D辅助重组人生长激素(rhGH)治疗特发性矮身材(ISS)儿童的疗效及对骨代谢指标、胰岛素样生长因子-1(IGF-1)、25羟维生素D[25-(OH)D]水平的影响。方法选取2015年1月-2017年6月本院收治的90例ISS患儿(ISS组),随机分为观察组与对照组,每组45例。另选同期性别、年龄相匹配的健康体检患儿45例作为正常组。对照组采用rhGH治疗,观察组采用rhGH加用钙尔奇D治疗。观察两组患儿治疗前及治疗后6、12个月身高(Ht)、骨龄(BA)、生长速度(GV)、身高均值标准差积分(HtSDS)、BA与生活年龄比值(BA/CA)、血清骨代谢指标[骨钙素(OC)、Ⅰ型前胶原氨基端延长肽(P1NP)]及25-(OH)D水平,并与45例健康正常儿童(正常组)进行比较。结果 ISS组的BA、Ht、GV、HtSDS、BA/CA及血清OC、PICP、IGF-1、25-(OH)D水平均显著低于正常组(P<0.05);治疗6、12个月,观察组的BA、Ht、GV、HtSDS、BA/CA及血清OC、PICP、IGF-1、25-(OH)D水平较治疗前显著提高(P<0.05),对照组的25-(OH)D水平无明显变化(P<0.05),且观察组的Ht、GV、HtSDS、HtSDS、及血清OC、PICP、IGF-1、25-(OH)D水平均显著高于对照组(P<0.05)。结论 ISS患儿存在骨代谢异常及IGF-1、25-(OH)D低水平现象,钙尔奇D辅助治疗可改善患儿的骨代谢状态并提高IGF-1、25-(OH)D水平,从而改善生长状况。 展开更多
关键词 特发性矮身材 钙尔奇D 骨代谢 胰岛素样生长因子-1 25羟维生素D
腹膜透析患者血清钙磷及全段甲状旁腺素达标率分析研究 预览
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作者 赵先 刘丽茹 +3 位作者 崔敏 赵美珠 张雨 何敏华 《大理大学学报》 CAS 2019年第2期70-75,共6页
目的:调查大理大学第一附属医院腹膜透析(PD)患者钙磷及全段甲状旁腺素(iPTH)的达标率,并探讨残余尿量对钙磷代谢的影响。方法:收集2017年10月至2018年3月期间在大理大学第一附属医院接受PD治疗3个月以上并规律随访的88例患者的临床资... 目的:调查大理大学第一附属医院腹膜透析(PD)患者钙磷及全段甲状旁腺素(iPTH)的达标率,并探讨残余尿量对钙磷代谢的影响。方法:收集2017年10月至2018年3月期间在大理大学第一附属医院接受PD治疗3个月以上并规律随访的88例患者的临床资料进行横断面研究。根据K/DOQI标准对血钙、磷和iPTH进行达标率统计,并与国内外研究进行比较。对残余尿量进行分组,比较组间钙、磷、iPTH的差异。结果:88例PD患者的血钙、磷、iPTH达标率分别为44.3%、40.9%、12.5%,3项同时达标为4.5%。与其他研究结果相比,钙磷达标率相近,iPTH达标率较低。无尿组(尿量<100mL/d)血磷、钙磷乘积高于有尿组(尿量≥100mL/d)(P<0.05)。结论:PD患者钙磷代谢紊乱及其继发性甲状旁腺功能亢进控制较差,有待于进一步加强。 展开更多
关键词 腹膜透析 全段甲状旁腺素 达标率
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Leaf water potential and gas exchange of eucalypt clonal seedlings to leaf solar protectant 预览
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作者 Talita Miranda Teixeira Xavier Jose Eduardo Macedo Pezzopane +1 位作者 Ricardo Miguel Penchel Jose Ricardo Macedo Pezzopane 《林业研究:英文版》 CAS CSCD 2019年第1期57-64,共8页
This experiment was carried out in acclimatized greenhouses with seedlings of two hybrid clones of Eucalyptus urophylla×Eucalyptus grandis.A sunscreen protector consisting of 62.5%calcium carbonate was sprayed on... This experiment was carried out in acclimatized greenhouses with seedlings of two hybrid clones of Eucalyptus urophylla×Eucalyptus grandis.A sunscreen protector consisting of 62.5%calcium carbonate was sprayed on the seedlings at weekly intervals.Water stress was induced by suspending irrigation until the soil reached 30%available water and water was then replaced so that it returned to field capacity.Gas exchange and leaf water status were measured after 50 days.The experiment was set up in a 4×2 factorial randomized block design in four distinct environments:(1)temperatures less than 21.2℃and vapor pressure deficit of 0.15 kPa;(2)intermediate temperatures of 24.2℃and vapor pressure deficit of 0.69 kPa;(3)high temperatures of 27.0℃and high vapor pressure deficit of 1.4 kPa;and,(4)high temperature of 27.0℃and vapor pressure deficit below 1.10 kPa.Two leaf sun protector treatments were used,with five replications each.High atmospheric demand acted as a stress factor for the seedlings during the initial growth phase.Applications of leaf sunscreen protector provided beneficial effects in maintaining optimum water status and gas exchanges of the plants under water stress. 展开更多
关键词 EUCALYPTUS urophylla×Eucalyptus grandis Calcium CARBONATE Water stress ATMOSPHERIC DEMAND
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