蔬菜,水果中微量锗含量的测定

采用胶束增溶分光光度法测定蔬菜、水果中微量锗的含量。样品采用硝酸－硫酸回流消化，用ＮａＯＨ溶解残渣，加ＨＣｌ定容进行测定。锗测定的批间变异系数为１．６％～２．３％，蔬菜、水果中微量锗的回收率为９８．２８％±２．５９％，对测定的条件进行了实验。用本方法测定蔬菜、水果中的微量锗，具有方法简单，准确度高，精密度好。     

Faraday Rotation of Dy2O3, CeF3 and Y3Fe5O12 at the Mid-Infrared Wavelengths

The relatively narrow choice of magneto-active materials that could be used to construct Faraday devices (such as rotators or isolators) for the mid-infrared wavelengths arguably represents a pressing issue that is currently limiting the development of the mid-infrared lasers. Furthermore, the knowledge of the magneto-optical properties of the yet-reported mid-infrared magneto-active materials is usually restricted to a single wavelength only. To address this issue, we have dedicated this work to a comprehensive investigation of the magneto-optical properties of both the emerging (Dy2O3 ceramics and CeF3 crystal) and established (Y3Fe5O12 crystal) mid-infrared magneto-active materials. A broadband radiation source was used in a combination with an advanced polarization-stepping method, enabling an in-depth analysis of the wavelength dependence of the investigated materials’ Faraday rotation. We were able to derive approximate models for the examined dependence, which, as we believe, may be conveniently used for designing the needed mid-infrared Faraday devices for lasers with the emission wavelengths in the 2-μm spectral region. In the case of Y3Fe5O12 crystal, the derived model may be used as a rough approximation of the material’s saturated Faraday rotation even beyond the 2-μm wavelengths.     

二羧乙基锗倍半氧化物中锗含量的石墨炉原子吸收分光光度测定法

本文用石墨炉原子吸收分光光度法测定二羧乙基锗倍半氧化物中锗的含量并以此作为评价该药物质量的依据,探讨了各种实验条件,选择了最佳测定浓度范围和实验溶剂以及最佳原子化温度和灰化温度。实验结果在0.1％～0.5％mg/L的浓度范围内其吸收度与浓度呈线性关系,平均回收率为103％,变异系数小于5,样品中锗的平均含量为42.7±1.69％,与42.9％理论值相近。本法具有灵敏、简便、快速、准确、重现性好等优点,可用于原料及制剂的分析。     

羧乙基锗倍半氧化物对正常和异丙基肾上腺素损伤培养乳鼠心肌细胞的影响

羧乙基锗倍半氧化物(Ge—132)能促进培养乳鼠心肌细胞DNA和RNA的合成,提高超氧化物歧化酶(SOD)的活性,维持细胞膜结构的稳定。异丙基肾上腺素可使心肌细胞乳酸脱氢酶(LDH)释放增加,细胞搏动停止,超微结构显示肌膜和线粒体严重受损。Ge—132可显著减少异两基肾上腺素引起心肌细胞释放LDH,维持细胞的搏动功能和超微结构的完整。     

Germanium dioxide induces mitochondria-mediated apoptosis in Neuro-2A cells

Germanium (Ge) is commonly used in the semiconductor industry as well as health-promoting and medical field. Biologically, germanium possesses erythropoietic, anti-microbial, anti-tumor, anti-amyloidosis, and immunomodulative effects. However, toxic effects of Ge-containing compounds on kidney, muscle, neuronal cells, and nerves have been reported. Mitochondrial dysfunction was found to be involved in the pathogenesis of GeO(2)-induced nephropathy and myopathy. Since it is well known that mitochondria play a major role in apoptosis triggered by many stimuli, an effort was made to examine whether the Ge-induced neurotoxicity occurs through mitochondria-mediated apoptosis. A mouse neuroblastoma cell line, Neuro-2A, was used in the present study. After incubating with 0.1-800microM of GeO(2) for 0-72h, the cell viability of Neuro-2A cells was inhibited in a dose- and time-dependent manner. Further analysis showed that aside from the changes in the nuclear morphology responsible for apoptosis, the release of cytochrome c, the loss of mitochondrial membrane potential, the translocation of Bax, and the reduction of Bcl-2 expression were also observed in Neuro-2A cells after GeO(2) treatment. These results indicate that the mitochondria-mediated apoptosis is involved in this in vitro model of GeO(2)-induced neurotoxicity.     

Transmission of Q-switched erbium:YSGG (λ=2.79 μm) and erbium:YAG (λ=2.94 μm) laser radiation through germanium oxide and sapphire optical fibres at high pulse energies

The erbium:YSGG and erbium:YAG lasers are used for tissue ablation in dermatology, dentistry and ophthalmology. The purpose of this study was to compare germanium oxide and sapphire optical fibres for transmission of sufficient Q-switched erbium laser pulse energies for potential use in both soft and hard tissue ablation applications. Fibre transmission studies were conducted with Q-switched (500 ns) Er:YSGG (=2.79 m) and Er:YAG (=2.94 m) laser pulses delivered at 3 Hz through 1-m-long, 450-m germanium oxide and 425-m sapphire optical fibres. Transmission of free-running (300 s) Er:YSGG and Er:YAG laser pulses was also conducted for comparison. Each set of measurements was carried out on seven different sapphire or germanium fibres, and the data were then averaged. Fibre attenuation of Q-switched Er:YSGG laser energy measured 1.3±0.1 dB/m and 1.0±0.2 dB/m for the germanium and sapphire fibres, respectively. Attenuation of Q-switched Er:YAG laser energy measured 0.9±0.3 dB/m and 0.6±0.2 dB/m, respectively. A maximum Q-switched Er:YSGG pulse energy of 42 mJ (26–30 J/cm²) was transmitted through the fibres. However, fibre tip damage was observed at energies exceeding 25 mJ (n=2). Both germanium oxide and sapphire optical fibres transmitted sufficient Q-switched Er:YSGG and Er:YAG laser radiation for use in both soft and hard tissue ablation. This is the first report of germanium and sapphire fibre optic transmission of Q-switched erbium laser energies of 25–42 mJ per pulse.     

双—β乙基碳酸锗倍半氧化物的抗肿瘤作用

本文报道一种有机锗化合物对小鼠移植瘤的影响,以此药(200mg/ks、po、ip)给荷瘤动物连续灌胃10天时,S_(180)、EAC(实体瘤)和肺癌 C_(57)被抑制,其抑癌率为73～91%。移植肿瘤40天后有机锗化合物组的小鼠存活率在50%以上。将此药经胃管给大鼠时,其 LD_(60)在10g/kg 以上。     

高锗酵母的研究

本研究从１２株食用酵母中选育出１株酵母（命名为Ｇｅ－１６８）在含锗麦芽汁培养基中培养高锗酵母，其菌体含锗量达到８１０．９ｐｐｍ，有机化程度达到９６．７％，表明以酵母为有机载体能较好地将二氧化锗转化为生物有机锗，菌体含锗量、菌体产量受培养基含锗量、培养温度、时间、ｐＨ等参数的影响，驯化可提高菌株富集锗能力。实验室结果提示，含锗量１００ｐｐｍ麦芽汁培养基、ｐＨ５．５、温度２９～３０℃，培养２４ｈ是较合     

羧乙基锗倍半氧化物对兔血小板聚集的影响

Ge-132体内外给药的剂量分别是5mg/kg和3.3—2062.5μg/ml时,均显著地抑制花生四烯酸和Ca~(2+)诱导的血小板聚集作用。体外实验证明对凝血酶诱导的聚集无效,但能显著地抑制可乐定诱导的聚集作用。     

有机锗Ge-132对氧自由基和由羟自由基诱导的脂质过氧化的影响

 有机锗Ge-132对邻苯二酚自氧化过程中产生的超氧阴离子自由基具有清除作用,但比抗坏血酸弱;Ge-132对由Fenton反应产生的羟自由基具有清除作用,对羟自由基诱导的大鼠肝匀浆脂质过氧化具有抑制作用?在清除羟自由基抗脂质过氧化方面,Ge-132的作用强于甘露醇?