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Marzenna Nasiadek Joanna Stragierowicz Anna Kilanowicz 《International journal of molecular sciences》2022,23(23)
Cadmium (Cd) is an environmental pollutant known to pose a public health issue. The mechanism of Cd toxicity on the uterus, including the protective role of metallothionein (MT), is still not fully understood. The aim of the study was to evaluate the degree of MT-Cd binding in the uterus of rats exposed per os to Cd at daily doses of 0.09, 0.9, 1.8 and 4.5 mg Cd/kg b.w. for 90 days. To assess the permanence of the bond, the rats were observed over long observation periods: 90 and 180 days after termination of exposure. Additionally, uterine concentration of Zn, Cu, Ca, Mg was determined. Cd leads immediately after exposure to a max. 30-fold increase in the concentration of Cd in the uterus, with only small amounts being bound to MT. After 90 days following termination of exposure, and especially after 180 days, an increase in MT-Cd concentration was noted for the three highest doses; even so, the degree of Cd binding by MT was still small. Additionally, the accumulation of Cd in the uterus disturbs the homeostasis of determined essential elements, manifested by a significant increase in Cu concentration and a decrease in Zn, Mg and Ca, especially 180 days after termination of exposure. The obtained results indicate that MT has only a slight protective role in the uterus and that Cd ions may have harmful effects not related to MT: directly on the uterine tissue, and indirectly by disturbing the homeostasis of its essential elements. 相似文献
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Ochiai Y Kaburagi S Okano Y Masaki H Ichihashi M Funasaka Y Sakurai H 《International journal of cosmetic science》2008,30(2):105-112
Oxidative stress caused by ultraviolet (UV) radiation generates reactive oxygen species (ROS) in the skin, induces the secretion of melanocyte growth and activating factors from keratinocytes, which results in the formation of cutaneous hyper-pigmentation. Thus, increasing the anti-oxidative ability of skin cells is expected to be a good strategy for skin-lightening cosmetics. Metallothionein (MT) is one of the stress-induced proteins and is known to exhibit a strong anti-oxidative property. We previously reported that a zinc(II) complex with glycine (Zn(II)(Gly)(2)) effectively induces MT expression in cultured human keratinocytes. To determine its potential as a new skin lightening active, we examined whether Zn(II)(Gly)(2) regulates the release of melanocyte-activating factors from UVB-irradiated keratinocytes and affects melanin production in a reconstructed human epidermal equivalent. Conditioned medium from UVB-irradiated keratinocytes accelerated melanocyte proliferation to 110%, and that increase could be prevented by pre-treatment with Zn(II)(Gly)(2). In addition, Zn(II)(Gly)(2) significantly reduced both the production of prostaglandin E(2) and proopiomelanocortin expression in UVB-irradiated keratinocytes. Zn(II)(Gly)(2) also decreased melanin production in a reconstructed human epidermal equivalent. These results indicate that MT-induction in the epidermis effectively up-regulates tolerance against oxidative stress and inhibits the secretion of melanocyte growth and activating factors from keratinocytes. Thus, Zn(II)(Gly)(2) is a good candidate as a new skin-lightening active. 相似文献
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Kurasaki Masaaki; Emoto Tadasu; Arias Ana Rosa Linde; Okabe Masashi; Yamasaki Futoshi; Oikawa Shinji; Kojima Yutaka 《Protein engineering, design & selection : PEDS》1996,9(12):1173-1180
We examined the independent self-assembly of the - and ß-fragmentsof human metallothionein (MT) into cadmiumbinding conformationin an Escherichia coli expression system, in addition to wild-typeMT expression. The expressed -fragment formed independentlythe structure of a metal-binding cluster without the aid ofthe ß-fragment. The -fragment and wild-type MT expressedin E.coli were purified and analyzed for their biochemical andspectroscopic properties. The apparent cadmium binding of the-fragment was approximately 12-fold greater than that for thewild-type MT, whereas in other respects the studied biochemicalproperties were similar. In contrast, we were unable to obtainany independently expressed ß-fragment as the cadmium-bindingform in this study. Possible explanations for this phenomenonare discussed. 相似文献
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研究了转金属硫蛋白基因平菇对不同模型小鼠抗氧化能力的影响。结果表明:在小鼠饲料中掺入1%和3.16%的转金属硫蛋白基因平菇干粉(前者相当于50~60kg体重的人每日摄食鲜菇1kg),可明显增强受辐照小鼠血清SOD活性,降低其血清MDA含量;明显增强铅中毒小鼠血清SOD活性和抗活性氧能力;对衰老小鼠血清SOD活性的降低、MDA含量的升高无明显改善作用。结论:转金属硫蛋白基因平菇可提高受辐照和铅中毒小鼠的抗氧化能力,对增强D-半乳糖致衰老模型小鼠抗氧化能力无明显效果。 相似文献
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Metals are essential cofactors for bio‐chemical processes, including oxidative phosphorylation, gene regulation and free‐radical homeostasis. Abnormalities in metal ions concentration in organisms, lead towards the eco‐physiological hazards in the aquatics. In aquatic organisms, metal absorption involves transfer of metals to the circulatory system following : uptake by the apical membrane; movement through the cell as well as interaction with intracellular ligands and efflux across the basolateral membrane. Sequestration of metals in an immobilized form occurs throughout the various tissues and organs involved in pathways for metal uptake, transport, utilization and release. Metallothioneins, metal binding proteins, regulate the essential metals (Cu, Zn), detoxify the toxic metals (Cd, Hg) and play key role to the sequestering metals. Plasma proteins play the central role in metal transport in the vertebrates. Besides, blood cells in aquatic invertebrates, hemocytes in mollusks concentrate a variety of metals. Aquatic organisms utilize renal, digestive pathways and diapedesis for the excretion of a variety of metals. This paper briefly reviews current information about the processes associated with metal uptake, transport, release, accumulation in the aquatic organisms and discuss about eco‐toxicological aspect of bio‐accumulation and suggest further necessary researches for future endeavor. 相似文献