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121.
Xunwei Wu Suhua Su Rihong Zhai Kekuan Chen Taiyi Jin Bo Huang Yuanfen Zhou Xianmin Ge Guoming Wei Ruiqing Liao 《Biometals》2004,17(4):435-441
The aim of this study was to evaluate the effect of ethylenediaminetetraacetic acid (EDTA) on cadmium (Cd) induced renal dysfunction. Seventeen workers (14 males, 3 females) were diagnosed with occupational Cd poisoning in 1986. These individuals had between 7 to 39 years of Cd exposure. From 1986 to 1999, patients received periodic EDTA therapy as part of their follow-up, all at the same hospital. Levels of urinary cadmium (UCd) and urinary beta2-microglobulin (B2M) were measured before and after each annual EDTA treatment period. Renal dysfunction was defined as urinary B2M > 0.8 mg/g Cr (creatinine). In these workers, patients with UCd level higher than 10 microg/g Cr in 1986 had abnormal B2M excretions (> or = 0.8 mg/g Cr) or trended to have abnormal B2M levels during the treatment period. However, in subjects with UCd concentration lower than 10 microg/g Cr in 1986, their urinary B2M excretions either remained normal (< 0.8 mg/g Cr) or returned to normal during the treatment period. The prevalence of renal dysfunction increased during the follow up period regardless of whether UCd levels increased or not, indicating a progressive renal dysfunction despite removal from Cd exposure. Our results suggest that reversibility of renal dysfunction caused by Cd related to the level of Cd exposure at the time of removal from exposure: renal dysfunction could be reversed if initial UCd < 10 microg/g Cr, but was irreversible when UCd > 10 microg/g Cr. Repeated examinations on these 17 Cd exposed workers from 1986 to 1999 also revealed that periodic administration of EDTA had no beneficial effects on chronic Cd-induced renal dysfunction. 相似文献
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探索恒河猴皮肤干细胞的体外培养及纯化条件,为进一步的研究奠定基础. 通过组织块培养法和消化培养法 在体外培养恒河猴表皮细胞,然后用Ⅳ型胶原吸附法吸附20 min,获得快吸附细胞. 对快吸附细胞进行克隆培养,并进行免疫细胞化学双标染色、RT PCR鉴定 β1 整合素和角蛋白15的表达,用流式细胞仪鉴定纯化前后的细胞中 β1 整合素和角蛋白15的阳性细胞比例,并通过透射电镜观察细胞的超微结构. 组织块培养法和消化培养法均可获得表皮细胞,Ⅳ型胶原纯化后的细胞胞体较小,饱满,核/浆比例大,细胞镶嵌状排列. 细胞克隆分析显示,细胞全克隆生长率高. 细胞免疫荧光显示,分选后的细胞显示 β1 整合素和角蛋白15阳性. RT PCR检查呈现 β1 整合素和角蛋白15的特异性片段. 流式细胞仪检查显示,纯化前的细胞中角蛋白15阳性细胞占总细胞中的比例为8%, β1 整合素阳性细胞的比例为10.7%;纯化后,角蛋白15阳性细胞的比例为89.4%, β1 整合素阳性细胞的比例为88.5%. 通过组织块培养法和消化培养法均可培养获得活性良好的表皮细胞,Ⅳ型胶原吸附法是一种简便、有效的皮肤干细胞分离方法,可以为进一步的眼表上皮替代重建眼表提供足量的高纯度的干细胞建立可靠的物质基础. 相似文献
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Mycopathologia - Onychomycosis was a common nail disease caused by dermatophytes, yeasts or molds. The prevalence of onychomycosis varied in different counties and it was necessary to understand... 相似文献
125.
Wang Linwen Wang Hui Wang Yuncai Che Yue Ge Zhiwei Mao Lingfeng 《Biodiversity and Conservation》2022,31(7):1771-1796
Biodiversity and Conservation - As a form of green infrastructure, green roofs can enhance urban biodiversity by providing complex vegetation structures, supplying increased foraging and roosting... 相似文献
126.
Jorge Mansur Medina Juliany Cola Fernandes Rodrigues Otacilio C Moreira Geórgia Atella Wanderley de Souza Hector Barrabin 《Memórias do Instituto Oswaldo Cruz》2015,110(1):48-55
Phytomonas serpens are flagellates in the family Trypanosomatidae that parasitise the
tomato plant (Solanum lycopersicum L.), which results in fruits with low commercial
value. The tomato glycoalkaloid tomatine and its aglycone tomatidine inhibit the
growth of P. serpens in axenic cultures. Tomatine, like many other saponins, induces
permeabilisation of the cell membrane and a loss of cell content, including the
cytosolic enzyme pyruvate kinase. In contrast, tomatidine does not cause
permeabilisation of membranes, but instead provokes morphological changes, including
vacuolisation. Phytomonas treated with tomatidine show an increased accumulation of
labelled neutral lipids (BODYPY-palmitic), a notable decrease in the amount of
C24-alkylated sterols and an increase in zymosterol content. These
results are consistent with the inhibition of 24-sterol methyltransferase (SMT),
which is an important enzyme that is responsible for the methylation of sterols at
the 24 position. We propose that the main target of tomatidine is the sterols
biosynthetic pathway, specifically, inhibition of the 24-SMT. Altogether, the results
obtained in the present paper suggest a more general effect of alkaloids in
trypanosomatids, which opens potential therapeutic possibilities for the treatment of
the diseases caused by these pathogens. 相似文献
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