变应性鼻炎患者血清中金属元素的测定

对４５例变应性鼻炎患者和３１例正常人进行了血清微量元素铜、锌、铁、钙、镁的检测。结果：变应性鼻炎患者血清中锌、钙明显下降（Ｐ＜０．０５），而Ｃｕ值（铜锌比）明显升高。铁镁值与正常组无明显差异。提示：铜、锌，钙参与变应性鼻炎的发病过程。     

耐热锻炼对钙和镁代谢的影响

目的　观察耐热锻炼对钙、镁代谢的影响 ,以探明夏季高温下体力锻炼时补充钙、镁的需要。方法　 2 0名健康青年男子 ,在炎热气候下 (三球温度指数WBGT 31 8℃ )进行 5km越野锻炼 ,2周内锻炼 1 0～ 1 2次。锻炼期前一天和后一天进行高温快步行进标准试验 (WBGT 30 3℃ ,受试者负重 1 6kg ,以速度为 4～5km/h快步行进 90min ,共 7km)。结果　耐热锻炼获得了热习服 ,显著提高了耐热能力。热应激时 ,汗钙、镁浓度分别为 1 35 2mmol/L和 0 36 4mmol/L ;热习服后 ,汗钙、镁浓度分别降低 34 6 %和 36 8% (P <0 0 5 ) ,全天流失量分别减少 1 1 2mg和 1 9 6mg。热应激日粪、尿钙排出量分别为 2 0 5 1mg和 31 4 2mg ,镁分别为2 0 7 6mg和 4 1 82mg;热习服后 ,粪钙、镁都分别减少 2 1 5 % (P <0 0 5 ) ,尿钙增加 1 8 1 % ,而尿镁减少6 6 %。热应激日钙、镁分别负平衡 2 6 1mg和 1 2 4mg ;热习服后热应激日钙负平衡 2 0 5mg ,镁则基本接近平衡。血清钙原处于正常值低限 ,镁尚在正常水平 ,热应激后钙升镁降 (P <0 0 5 ) ;热习服后 ,血清钙降至正常值以下 ,镁也下降 7 7% (P <0 0 5 ) ;高温快步行进标准试验后 ,血清钙下降 ,并与锻炼期前差异有非常显著性 (P <0 0 1 ) ,而实验期间钙、镁摄取量仅为 30     

不同镁离子浓度对TTV核酸检测的影响

目的 :确定输血传播病毒TTV核酸检测方法中的最佳镁离子浓度。方法 :根据TTVORF2区基因序列 ,设计并合成引物和荧光标记探针。结果 :在确定最佳引物浓度之后 ,分别建立不同镁离子浓度的PCR检测体系 ,根据反应曲线选择最佳镁离子浓度。结论 :最佳镁离子浓度应为 4 .0mmol/L。     

原子吸收火焰法测定门冬氨酸钾镁注射液中钾、镁含量

目的 采用原子吸收火焰法测定门冬氨酸钾镁注射液中钾、镁的含量.方法 采用空气.乙炔火焰原子吸收光谱法,氯化镧作为释放剂.结果 本方法的平均回收率分别为100.5%(钾)、102.3%(镁).结论 本方法操作简便,结果准确,适合于门冬氨酸钾镁注射液中钾、镁的含量测定.     

Radioligand binding and functional responses of ligands for human recombinant adenosine A(3) receptors

The binding and functional properties of adenosine receptor ligands were compared in Chinese hamster ovary cells transfected with human adenosine A(3) receptors. Inhibition of [(125)I]-aminobenzyl-5'-N-methylcarboamidoadenosine ([(125)I]-AB-MECA) binding by adenosine receptor ligands was examined in membrane preparations. Inhibition of forskolin-induced cAMP accumulation by agonists was measured using a cAMP enzyme immunoassay. The rank order of agonist potency for both assays was N(6)-(3-iodobenzyl)-adenosine-5'-N-methyluronamide (IB-MECA) > 5'-N-ethylcarboxamidoadenosine (NECA) > (-)-N(6)-[(R)-phenylisopropyl] adenosine (R-PIA) > 4-aminobenzyl-5'-N-methylcarboxamidoadenosine (AB-MECA) > N(6)-cyclopentyl adenosine (CPA) > adenosine. The radioligand binding rank order of antagonist potency was N-[9-chloro-2-(2-furanyl)[1,2,4]-triazolo[1,5-c]quinazolin-5-benzeneacetamide (MRS1220) > 1,3-dipropyl-8-cyclopentylxanthine (DPCPX) > 8-phenyltheophylline (8-PT) > 8-(p-sulfophenyl)-theophylline (8-SPT). MRS1220 competitively inhibited the effect of IB-MECA on cAMP production, with a K(B) value of 0.35 nm. These data are characteristic of adenosine A(3) receptors. The absence of Mg(2+) and presence of guanosine 5'-(gamma-thio)triphosphate (GTPgammaS) significantly reduced agonist binding inhibition potency, indicating binding to high- and low-affinity states. The IB-MECA, NECA and R-PIA IC(50) values were greater for the cAMP assay than for radioligand binding, suggesting an efficient stimulus-response transduction pathway.     

糖尿病患者血清镁与尿蛋白三项的关系探讨

目的　探讨尿蛋白三项与血清镁 (Mg2 + )水平的关系。方法　分别采用Arsenzo -III方法及放射免疫分析法检测 2 46例 2型糖尿病患者血清Mg2 + 水平及尿蛋白三项。结果　血清Mg2 + 不仅与尿 β2 微球蛋白 ( β2 -MG)、免疫球蛋白 (IgG)、白蛋白 (Alb)直线相关 (P <0 0 0 5 ) ,并与年龄直线相关 (P <0 0 0 5 )。血清Mg2 + 随着尿蛋白三项中的一种或两种不同蛋白的升高而升高 (P <0 0 0 5 ) ,然而单存Alb升高组血清Mg2 + 却较三项正常组稍低 (P =0 991)。结论　糖尿病肾病 (DN)病情越重血清Mg2 + 水平越高 ,DN进入临床期后使用胰岛素增敏剂及镁剂应慎重。尿蛋白三项与血清Mg2 + 的联合检测有助于DN早期诊断     

Fabrication and characterization of Mg/P(LLA-CL)-blended nanofiber scaffold

Poly(l-lactic acid-co-ε-caprolactone) (P(LLA-CL)) is a kind of copolymer polymerized from lactic acid and ε-caprolactone. Electrospun P(LLA-CL) nanofibers have good biocompatibility, biodegradability, and mechanical property. However, this type of nanofibers will produce acid groups during the degradation, so that, the pH value of the environment will decrease and result in tissue inflammation. On the other hand, Magnesium (Mg) alloy tissue engineering scaffolds will show alkaline during the degradation because of the electrochemical corrosion. Based on the principle of acid-based neutralization, combination of these two kinds of materials through electrospinning could keep the pH of the degradation environment neutral. In this paper, fabrication and characterization of Mg/P(LLA-CL)-blended nanofiber scaffolds with different ratios will be studied by scanning electron microscopy and universal materials testing machines to observe the morphology and mechanical properties of nanofibers, respectively. Furthermore, PIECs were cultured and seeded on the scaffolds for different time to evaluate the proliferation behavior on the scaffolds by MTT assay. The degradation tests of the samples lasted for three?months in phosphate-buffered saline to evaluate the pH values of degradation solutions and the weight loss of nanofibers during degradation. The results showed that the mechanical property and biocompatibility of Mg/P(LLA-CL)-blended nanofibers were worse than that of pure P(LLA-CL). Moreover, the addition of Mg in the nanofibers accelerated the weight loss of the Mg/P(LLA-CL) blending fibers and increased the pH values of the environment during degradation of Mg/P(LLA-CL)-blended nanofibers.     

Relationship between Biodegradation Rate and Grain Size Itself Excluding Other Structural Factors Caused by Alloying Additions and Deformation Processing for Pure Mg

This work studied the relationship between biodegradation rate and grain size itself, excluding other structural factors such as segregations, impure inclusions, second phase particles, sub-structures, internal stresses and textures caused by alloying additions and deformation processing for pure Mg. A spectrum of grain size was obtained by annealing through changing the annealing temperature. Grain boundary influenced the hardness and the biodegradation behavior. The hardness was grain size-dependent, following a typical Hall–Petch relation: HV=18.45+92.31d−12. The biodegradation rate decreased with decreasing grain size, following a similar Hall–Petch relation: Pi=0.17−0.68d−12 or Pw=1.34−6.17d−12. This work should be helpful for better controlling biodegradation performance of biodegradable Mg alloys through varying their grain size.     

Optical Properties of Magnesium-Zinc Oxide for Thin Film Photovoltaics

Motivated by their utility in CdTe-based thin film photovoltaics (PV) devices, an investigation of thin films of the magnesium-zinc oxide (Mg_xZn_1−xO or MZO) alloy system was undertaken applying spectroscopic ellipsometry (SE). Dominant wurtzite phase MZO thin films with Mg contents in the range 0 ≤ x ≤ 0.42 were deposited on room temperature soda lime glass (SLG) substrates by magnetron co-sputtering of MgO and ZnO targets followed by annealing. The complex dielectric functions ε of these films were determined and parameterized over the photon energy range from 0.73 to 6.5 eV using an analytical model consisting of two critical point (CP) oscillators. The CP parameters in this model are expressed as polynomial functions of the best fitting lowest CP energy or bandgap E₀ = E_g, which in turn is a quadratic function of x. As functions of x, both the lowest energy CP broadening and the Urbach parameter show minima for x ~ 0.3, which corresponds to a bandgap of 3.65 eV. As a result, it is concluded that for this composition and bandgap, the MZO exhibits either a minimum concentration of defects in the bulk of the crystallites or a maximum in the grain size, an observation consistent with measured X-ray diffraction line broadenings. The parametric expression for ε developed here is expected to be useful in future mapping and through-the-glass SE analyses of partial and complete PV device structures incorporating MZO.     

Transport Mechanisms and Dielectric Features of Mg-Doped ZnO Nanocrystals for Device Applications

Magnesium-doped zinc oxide “ZnO:Mg” nanocrystals (NCs) were fabricated using a sol gel method. The Mg concentration impact on the structural, morphological, electrical, and dielectric characteristics of ZnO:Mg NCs were inspected. X-ray diffraction (XRD) patterns display the hexagonal wurtzite structure without any additional phase. TEM images revealed the nanometric size of the particles with a spherical-like shape. The electrical conductivity of the ZnO NCs, thermally activated, was found to be dependent on the Mg content. The impedance spectra were represented via a corresponding circuit formed by a resistor and constant phase element (CPE). A non-Debye type relaxation was located through the analyses of the complex impedance. The conductivity diminished with the incorporation of the Mg element. The AC conductivity is reduced by raising the temperature. Its plot obeys the Arrhenius law demonstrating a single activation energy during the conduction process. The complex impedance highlighted the existence of a Debye-type dielectric dispersion. The various ZnO:Mg samples demonstrate high values of dielectric constant with small dielectric losses for both medium and high-frequency regions. Interestingly, the Mg doping with 3% content exhibits colossal dielectric constant (more than 2 × 10⁴) over wide temperature and frequency ranges, with Debye-like relaxation. The study of the electrical modulus versus the frequency and at different temperatures confirms the non-Debye relaxation. The obtained results reveal the importance of the ZnO:Mg NCs for device applications. This encourages their application in energy storage.