He-Ne激光对增强紫外线-B辐射小麦叶片胞质ATP酶活性的影响

为探讨He-Ne激光对UV-B辐射损伤修复途径,采用He-Ne激光(5 mW·mm-2)辐照方法,对增强UV-B(10.08 kJ·m-2·d-1)辐射下的六日龄小麦叶片胞质中的Ca2+-ATP酶,Mg2+-ATP酶和Na+-/K+-ATP酶活力变化进行研究.结果表明,经UV-B处理(B)后,小麦叶片中的Ca2+-ATP酶和Mg2+-ATP酶活性低于对照组(CK)(P＜0.01),Na+/K+-ATP酶活性高于对照组(CK)(P＞0.05);单独激光(L)处理,小麦叶片中的Ca2+-ATP酶,Mg2+-ATP酶和Na+/K+-ATP酶活性高于对照组(P＜0.01);经He-Ne激光和UV-B复合处理(BL)后,小麦叶片中Ca2+-ATP酶和Mg2+-ATP酶活性高于UV-B处理组,低于对照组,而Na+/K+-ATP酶的活性高于对照组.说明He-Ne激光能够提高ATP酶活性.表明He-Ne激光对增强UV-B辐射造成小麦的损伤具有一定的修复作用.     

RCa_2Mg_2(VO_4)_3(R=Li,K,Na)荧光粉的制备及发光性能研究

采用高温固相法合成了RCa2Mg2(VO4)3(R=Li,K,Na)自激活系列荧光粉,并用X射线衍射仪和荧光分光光度计对合成样品的结构和发光性能进行了表征。结果表明:在750℃下煅烧得到的RCa2Mg2(VO4)3荧光粉具有较好的晶体结构。在331 nm的紫外光激发下,RCa2Mg2(VO4)3荧光粉在491 nm处具有较强的宽峰发射,其中Na Ca2Mg2(VO4)3的发光强度最好。Li Ca2Mg2(VO4)3、KCa2Mg2(VO4)3、Na Ca2Mg2(VO4)3的色坐标分别为(0.245,0.392)、(0.265,0.425)、(0.211,0.326),位于蓝绿光区。Eu3+掺杂后,Na Ca2Mg2(VO4)3:Eu3+样品光谱图中620 nm处出现Eu3+的发射峰,有效促使Na Ca2Mg2(VO4)3色坐标从蓝绿区(0.211,0.326)移到近白光区(0.260,0.322)。     

牛磺酸对顺铂导致培养的原代兔肾小管细胞损伤的保护作用

目的：研究牛磺酸对顺铂导致培养的原代兔肾近端小管细胞(PTC)损伤的保护作用。方法：在体外建立原代兔肾近端小管细胞培养。采用溴乙锭荧光法测量DNA链间交联和Fur-2／AM测量细胞内游离钙离子浓度。首先将牛磺酸(0．1，1，10g．L^-1)与PTC保温24小时,然后，加入顺铂使其终浓度达到26μmol.L^-1,再继续保温24小时。顺铂损伤组同样培养48小时。前24小时不加入牛磺酸和顺铂,后24小时加入顺铂使其终浓度为26μmol.L^-1。对照组不加入牛磺酸和顺铂，同样培养48小时。结果：顺铂导致损伤组形成DNA链间交联和细胞内游离钙离子浓度升高．牛磺酸1．10g．L^-1可明显降低DNA链间交联和细胞内游离钙离子浓度。结论：牛磺酸可保护顺铂对PTC的损伤。     

低强度微波对烟草叶片细胞膜系统和POD同工酶的非热效应

在300MHz低强度微波辐射下,烟草叶片细胞膜电解质渗漏率增加,膜脂过氧化产物丙二醛(MDA)含量增加,超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性降低,表明微波抑制了细胞膜保护酶系统的活性,使膜脂产生了过氧化作用。进一步的研究表明,烟草类囊体膜膜脂不饱和度指数(index of unsaturated fatty ac id,IUFA)下降,膜流动性减小,类囊体膜结合酶Ca2 -ATP酶和Mg2 -ATP酶活性升高。低强度微波还使烟草叶片过氧化物酶(POD)活性发生了变化,电泳分析显示,POD同工酶谱的染色和条带都有所改变。烟草叶片细胞发生的这些变化是微波对光合细胞的一种非热效应。     

牛磺酸在体外对缺血/再灌注新生大鼠心肌细胞内游离钙的影响

目的:观察低氧、复氧对心肌细胞内Ca2+浓度([Ca2+]i)的影响,以及牛磺酸模拟心肌缺血/再灌注(I/R)过程中减轻钙超载的作用。方法:采用SD大鼠乳鼠进行心肌细胞培养,建立模拟I/R模型。实验分4组:①正常对照组;②模拟缺血/缺氧组:细胞低氧180min;③模拟I/R组:细胞低氧180min,复氧180min;③牛磺酸+I/R组:先加入终浓度为20mmol.L-1的牛磺酸,再行低氧180min,复氧180min。以Fluo-4/AM荧光指示剂负载,应用激光共聚焦显微镜技术检测心肌细胞[Ca2+]i变化。结果:对照组心肌细胞[Ca2+]i荧光强度(23.71±2.37)U和荧光光密度较低;低氧180min后复氧即刻,[Ca2+]i荧光强度开始增加(57.52±8.31),复氧180min后[Ca2+]i荧光强度(71.13±4.74)U和光密度显著增高(P<0.01vs对照组)。而牛磺酸组细胞内荧光强度和光密度较模拟I/R组显著降低[(42.42±4.17)U vs(71.13±4.74)U,P<0.01]。结论:心肌细胞缺血/缺氧导致Ca2+超载;模拟I/R Ca2+超载加剧,而牛磺酸有明显减轻心肌细胞模拟I/R时Ca2+超载的作用。     

NaK(E)态的离解和Na(3PJ)精细结构分支比

研究了Na(3S) +K(4S) +nhν→Na(3PJ) +K(4S) +(n - 1 )hν过程 ,激光频率ν调到Na共振跃迁的两翼 ,分支比定义为I(D1 ) /I(D2 ) ,I(D1 ) ,I(D2 )分别是NaD1 ,D2 线的强度 ,在K密度 2～ 8× 1 0 2 0 m-3 范围内 ,测量了从Na共振跃迁的蓝翼 30 0cm-1 到红翼 1 0 0cm-1 的分支比 ,得到了离解率之比和精细结构转移截面 ,在近翼 ,分支比与ν有很大的关系。用对Na3PJ 态共振激发的方法 ,也得到了精细结构转移截面 ,对结果进行了讨论     

碱金属氧化物添加剂对(Mg_(1–x)Ca_x)TiO_3陶瓷微波性能的影响

采用固相反应法制备了(Mg1–xCax)TiO3微波介质陶瓷。探讨了复合添加Na2O和K2O对(Mg1–xCax)TiO3陶瓷烧结性能和介电性能的影响。结果表明:复合添加碱金属氧化物,陶瓷的主晶相为MgTiO3和CaTiO3,同时,可以抑制中间相MgTi2O5的产生,有效降低陶瓷的烧结温度至1280℃。当Na2O和K2O添加总量为质量分数1.2%,且Na2O/K2O质量比为2∶1时,所制陶瓷介电性能最佳:εr=19.71,Q.f=3.59×104GHz(7.58 GHz),τf=–1.40×10–6/℃。     

Yb~(3+),Er~(3+)共掺磷酸盐铒玻璃光谱性质研究

研究了Yb3+ ,Er3+ 共掺磷酸盐铒玻璃的吸收光谱和荧光光谱性质。通过测定和计算各种Yb3 + ,Er3 + 共掺磷酸盐铒玻璃光谱参数 ,初步探明了Yb3+ 离子浓度、碱金属氧化物R2 O(R =Li,Na ,K)和碱土金属氧化物MO(M =Zn ,Mg ,Ca,Ba)的引入及网络生成体P2 O5 的含量对Yb3 + ,Er3 + 共掺磷酸盐铒玻璃光谱性质的影响。在Yb3+ ,Er3+共掺磷酸盐铒玻璃中实现了Er3+ 荧光寿命达 7 5ms,受激发射截面为 0 8× 10 - 2 0 cm2 的光谱特性 ,为今后该玻璃的激光实验提供了重要参数     

铜掺杂量对钴酸钙热电性能的影响研究

采用sol-gel法制备了掺Cu的钴酸钙(Ca3Co4O9)热电材料,研究了Cu掺杂量对其物相、电导率σ、Seebeck系数S和功率因子P的影响。结果表明:随着Cu掺杂量的增加,试样中Ca3Co4O9的含量下降,但试样的电导率增加;试样的Seebeck系数和功率因子先增加后下降。试样(Ca0.90Cu0.10)3Co4O9在973 K时的功率因子最大,为15.3×10–4 W.m–1.K–2。     

电镜酶细胞化学技术及其应用

电镜酶细胞化学是在超微结构水平上研究酶的活性定位和变化的新技术。用此技术,有利于综合分析细胞的超微结构特征与酶活性分布之间的相互联系,对研究各种生理病理情况下酶的定位和代谢特征有很重要的意义。近年来,我们摸索、引用或改进了十八种酶(5′—核苷酸酶、核苷二磷酸酶、钠—钾—ATP酶、Mg~(++)-ATP酶、Ca~(++)-ATP酶、细胞色素氧化酶、腺苷酸环化酶、糖原合成酶、LDH、MAO、ALP、ACP、AChE、SDH、CMP酶、TPP酶、G-6-P酶、NADP酶)的电镜细胞化学方法,并应用于高压氧医学和脑肿瘤酶活性定位研究。在应用中我们体会到:(1)用2％多聚甲醛—0.5％戊二醛(0.1M二甲砷酸缓冲液或PBS配成,加6.5％蔗糖)混合固定液固定对大多数酶是合适的。少数酶如SDH不耐固定,须用     

低能量He-Ne激光照射体外循环血液对IDDM患者红细胞膜ATPase活性的影响

本文研究了低能量He-Ne激光照射体外循环血液对IDDM患者红细胞膜ATPase(Na~+/K~+-ATPase,Ca~(2+)-ATPase、Mg~(2+)-ATPase)活性的影响,结果表明,IDDM患者膜泵功能活性显著降低;低能量He-Ne激光照射血液可激活膜ATPase活性。作者讨论了膜泵功能降低及激光作用的可能机制。     

低功率激光对细胞质膜通透性及细胞功能的影响

目的:探索低功率激光对细胞质膜通透性及细胞功能的影响。方法:以波长为632.8nm,功率密度为5.4mW/cm~2的氦氖激光照射人外周血淋巴细胞15、30、60分钟,并采用钙荧光指示剂Fura—2/Am定量测试法检测淋巴细胞内游离钙浓度和质膜Ca~(2+)—Mg~(2+)—ATP酶活性变化。结果:照射后淋巴细胞内游离钙浓度明显低于正常(P<0.05);同时细胞膜Ca~(2+)—Mg~(2+)—ATP酶活性增加(P<0.05);而且照射后细胞内游离钙浓度降低与质膜上Ca~(2+)—Mg~(2+)—ATP酶的激活呈负相关。结论:低功率激光照射激活细胞膜Ca~(2+)—Mg~(2+)—ATP酶活性,使细胞膜对钙通透性发生变化,且影响到细胞内Ca~(2+)贮存,造成细胞膜通透性和细胞功能的改变。     

A Progress Report on Metal–Sulfur Batteries

Nonaqueous conversion‐reaction sulfur chemistry has been attracting increasing attention over the past decade for the development of next‐generation lithium‐based batteries. Li–S batteries are currently approaching a nexus stage from lab‐scale experiments to possible pragmatic applications. Inspired by the success of Li–S chemistry, other metal–sulfur batteries with a variety of metallic anodes, such as sodium, potassium, magnesium, calcium, and aluminum, have also started to attract attention. In comparison to lithium, Na, Mg, Al, K, and Ca are naturally more abundant and affordable. The Na‐S, Mg‐S, Al‐S, K‐S, and Ca‐S battery systems provide a great potential for improving the volumetric energy density of sulfur‐based batteries. The multivalent metal‐sulfur systems, Mg‐S, Al‐S, and Ca‐S, offer better safety features as well. However, the research and development on Na‐S, Mg‐S, Al‐S, K‐S, and Ca‐S batteries is far behind the Li–S system due to many critical challenges. In this progress report, the fundamental principles of various metal–sulfur chemistries are first presented and compared. Then, the historical progress, recent advances, and key challenges of the Li–S, Na‐S, Mg‐S, Al‐S, K‐S, and Ca‐S systems are summarized and discussed. Finally, future efforts and directions for both the fundamental and practical research are prospected.     

Applying secondary ion mass spectrometry to the analysis of elements in goblet cells of conjunctiva

We investigated the location of elements in the goblet cells of rat conjunctiva by analyzing ion images produced by secondary ion mass spectrometry (SIMS) and comparing them with those produced by energy dispersive X-ray analyser (EDX). Conjunctivas of normal Spraque-Dawley rats were quenched in propane prechilled liquid nitrogen. Semi-thin sections were made with a cryo-ultramicrotome, freeze-dried, carbon-coated and observed under a light microscope, SIMS and scanning electron microscope (SEM). In the element analysis by SIMS, images of positive ions were examined with an O2+ primary ion source and images of negative ions with a Ga+ ion source. The same sections were observed and analysed with SEM-EDX. Morphological features and images of elements with SIMS and EDX were compared. Na, Mg, K, and Ca were detected as positive ions and OH, CN, P, S, and Cl as negative ions with SIMS, but C, N, O, Na, Mg, P, S, Cl, K, and Ca were detected with EDX. The spatial resolution of SIMS in element location was higher than that of EDX. Many elements were clearly located in the goblet cells on ion images by SIMS. Element ion images were demonstrated more densely in goblet cells than in other parts within conjunctiva and by SIMS compared to EDX. SIMS is a useful method for the detection of elements and their locations in ocular tissues and cells.     

Presenilin1基因对心肌细胞肌浆网钙容量的影响

目的:探讨Presenilin1基因对心肌细胞肌浆网钙容量的影响.方法:本实验以AAV-9为载体构建心肌特异性PS1-shRNA重组腺相关病毒,通过尾静脉注射PS1-shRNA重组腺相关病毒干扰大鼠心肌组织中Presenilin1基因的表达,并利用激光扫描共聚焦显微镜检测并记录心肌细胞肌浆网钙容量及舒张期自发钙释放事件的变化;同时,采用western blot技术分析各组大鼠心肌组织中雷诺丁受体及钙泵表达水平的改变.结果:与对照组相比,PS1-shRNA重组腺相关病毒干预组大鼠心肌细胞肌浆网钙容量显著降低,自发钙释放事件明显增加;雷诺丁受体表达水平略降低,钙泵表达水平无显著性变化.结论:Presenilin1基因表达水平降低会引起心肌细胞钙泄漏,从而造成心肌细胞肌浆网钙容量降低.     

Electron microprobe analysis of impurity heterogeneities in thermally grown silicon oxide

The electron probe X-ray microanalyzer is a powerful tool for studying impurity distribution and motion in thin films. This analytical instrument is capable of detecting metallic impurities present in areas as small as 1 × 10^-6mm²and in concentrations of greater than 1 × 10¹⁹atoms/cm³. The analysis requires no sample preparation and is essentially a nondestructive test. This instrument was used to examine unoxidized and oxidized silicon surfaces and a finished microcircuit. With the electron microprobe, aluminum-bearing regions approximately one microns in diameter were detected on the bare surface of mechanically polished silicon slices. These aluminum-rich regions are believed to be alumina abrasive used in polishing. If these regions are not removed by chemical etching they will generate oxide defects during oxidation. These defects were found to contain Al (1 × 10²¹atoms/cm³and Na (1 × 10²⁰atoms/cm³). Other oxide defects, i.e., pinholes, generated during oxidation varied in size from 0.5 to 5.0 microns and were found to contain Na (1×10²¹atoms/cm³) and K (5×10²¹atoms/cm³). Mg and Ca (1 × 10²⁰atoms/cm³) were occasionally observed in these defects. After oxidation, all these impurities could be removed with a hot hydrochloric acid and deionized water rinse; surprisingly, this treatment reduced the silicon surface charge in the MOS structure (X_{0} cong 1500Å) by approximately 1.4 × 10¹¹charges/cm². The surface charge could be further reduced by heating the oxidized wafer at 900°C in a silicon nitride tube.     

Ca2+, Mg2+-ATPase activity of the erythrocyte membrane in patients with lung cancer

The activity of erythrocyte membrane Ca2+, Mg2+-ATPase (EC 3.6.1.3) was studied in 22 patients suffering from lung cancer. The enzyme activity was found to increase. The observed changes indicate significant disturbances in the mechanisms of ion transport in organs and tissues during tumour growth.     

小鼠先天性心脏畸形动物模型的建立

目的：利用丙戊酸（VPA;2-propyl-pentanoic acid）干扰孕鼠子宫内胚胎的发育,致胎鼠心脏发育畸形〔1,2〕,为探讨先天性心脏病的发病机制建立可靠的动物模型。方法：妊娠第6,7,8,9天的ICR孕鼠腹腔注射VPA（700mg/kg）为时间处理组;妊娠第7天的ICR孕鼠腹腔注射200mg/kg,400mg/kg,600mg/kg,700mg/kg的VPA,为处理组;腹腔注射0.9%Nacl为对照组;观察胎鼠心脏畸形发生率。结果：第6,7,8,9天孕鼠在VPA作用后,胎鼠心脏畸形发生率均明显高于对照组（p〈0.05）,以第7天孕鼠组的胎鼠心脏畸形发生率20.90%为最高。第7天孕鼠用200mg/kg,400mg/kg,600mg/kg,700mg/kgVPA腹腔注射后,胎鼠心脏畸形发生率均高于对照组（p〈0.05,以700mg/kg剂量为最高。结论：VPA可致胎鼠心脏发育畸形,以孕期第七天,700mg/kg剂量胎鼠心脏畸形发生率为最高。     

胆小管超微细胞酶学研究

以电镜细胞化学的方法,观察了小鼠胆小管酶的分布。观察的12种酶中,NDPase和G6Pase三种酶分布于胆小管微绒毛;AlPase、Na~+-K~+ATPase、Mg~(++)-ATPase、Ca~(++)-ATPase、CMPase、ACase和5＇-Nase等7种酶分布于胆小管微绒毛,也分布于肝细胞邻接面细胞膜和Disse间隙微绒毛;ACPase、细胞色素氧化酶以及线粒体ATPase不分布胆小管微绒毛,也不分布Disse间隙微绒毛和肝细胞膜。据信,胆小管微绒毛上的酶参与胆汁成份的转运,提供转运所需能量以及还可能与某些代谢过程有关。本实验中磷酸水解酶类使用的铈基法及亚铁氰化钾半还原的锇酸后固定法,效果优于铅法。