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91.
92.
木质素过氧化物酶是一种重要的具有工业应用前景的木质素降解酶,但已报道真菌来源的木质素过氧化物酶只能在酸性低温条件下发挥作用,限制了其进一步的工业应用.通过培养一株耐热耐碱放线茵——绿色糖单孢茵发酵产酶,采用DEAE-Cellulose,CM-Cellulose和Superdex 75凝胶过滤层析等分离纯化方法,得到一种具有耐热耐碱特性的木质素过氧化物酶.经凝胶电泳检测其为单一蛋白,分子量为41 kD.最终纯化倍数达到20倍,活性回收率为6%.采用LTQ法对纯酶进行蛋白质归类鉴定,得到其部分氨基酸片段,为该酶的进一步分子生物学研究奠定基础. 相似文献
93.
Leina Zheng Wenwei Zhang Xingang Chen Jing Ma Weiwei Chen Zhigang Zhao Huqu Zhai Jianmin Wan 《Journal of Plant Biology》2011,54(5):321-328
Protein content (PC) and protein index (PI) play important roles in determining nutritional quality in rice (Oryza sativa L.). We used 71 lines derived from “Asominori/IR24” to analyze the developmental behavior of PC and PI through unconditional
and conditional QTL mapping methods. In all, 10 unconditional QTLs and 6 conditional QTLs for PC, and 11 unconditional QTLs
and 9 conditional QTLs for PI, were identified at four stages of grain filling. More were identified in the first three stages
than at the final stage. Temporal patterns of gene expression for PC and PI differed over time, with several QTLs being expressed
across two or three stages but many being expressed at only one stage. Some of these QTLs were closely linked with maturity
QTLs reported previously. Many QTLs for PC and PI were co-localized, supporting the significant correlation found between
PC and PI. Our results suggest that dynamic QTL mapping might be a valid means for revealing more genetic information about
protein accumulations during seed development. 相似文献
94.
95.
DKK1 (dickkopf homolog 1) is a potent inhibitor of the canonical Wnt/β-cantenin signalling pathway, which plays a pivotal role
in myogenesis, adipogenesis, and many other crucial biological processes. In this study, DKK1 was assigned to porcine 14q25-26 by using the radiation hybrid (IMpRH) panel. A G1757A single nucleotide polymorphism site
by Csp6I PCR-RFLP was identified. Association analysis showed that different genotypes were associated with loin muscle area (P = 0.0281). Semi-quantitative-RT-PCR analysis revealed that DKK1 was highly expressed in spleen and lymph node at two developmental stages, while in skeletal muscle, further real-time PCR
quantified that DKK1 was down-regulated in Large White pigs compared to Tongcheng pigs, accompanied by the down-regulation of CTTNB1 and TCF4, the up-regulation of LRP6, suggesting that the phenotypic difference between lean and obese pigs might be correlated with the activity of Wnt/β-cantenin
signalling pathway. 相似文献
96.
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
97.
南四湖自然保护区具有较高的生态保护地位和经济价值。研究以南四湖自然保护区1975—2015年8期土地利用类型数据为基础, 借助SPSS、ArcGIS等软件, 分析南四湖自然保护区近40年土地利用变化及其对生态系统服务价值时空分布的影响。结果表明: 1975—2015年水体始终是南四湖自然保护区的优势土地利用类型。40年间未利用地面积减少88.90% (8807.68 hm2), 而水田、草地、旱地、建成区、林地和水体面积分别增加4626.45 hm2、405.06 hm2、1660.67 hm2、401.54 hm2、76.76 hm2和1621.60 hm2。40年间南四湖自然保护区的生态系统服务总价值增加了0.03% (1.13×106 US$), 其中支持服务功能价值减少1.14×107 US$, 文化服务功能价值减少5.61×106 US$, 供给服务功能价值减少2.15×106 US$, 仅调节服务功能价值增加2.02×107 US$。表现在空间上则是自然保护区西侧生态系统服务价值变化较东侧更为明显。导致1975—2015年生态系统服务价值变化的主要影响因子是水体和未利用地面积的改变, 生态系统服务价值与水体面积呈现显著正相关, 与未利用地呈现显著负相关。研究结果能为南四湖自然保护区的土地利用决策提供理论支持。 相似文献
98.
99.
Differential intensity‐dependent effects of pulsed electromagnetic fields on RANKL‐induced osteoclast formation,apoptosis, and bone resorbing ability in RAW264.7 cells 下载免费PDF全文
100.
Chunlei Li Yanxia Fu Yinyin Wang Yanhua Kong Mengdi Li Danhui Ma Wanli Zhai Hao Wang Yuting Lin Sihan Liu Fangli Ren Jun Li Yi Wang 《Cell biochemistry and function》2017,35(7):420-425
Mesenchymal stromal cells (MSCs) have been extensively investigated as a potential antiinflammatory treatment in many inflammatory‐related diseases; however, it remains unclear whether MSCs could be used to treat acute allergic rhinitis. A rat model of allergic rhinitis was treated with MSCs. The effect of MSCs on the inflammation of allergic rhinitis was evaluated by sneezing, nose rubbing, the pathology of the nasal mucosa, and the expression of interleukin 4, tumour necrosis factor alpha, and immunoglobulin E in the serum of rats. Also, the population of MSCs isolated from umbilical cords of humans was evaluated to determine if they could inhibit the symptoms and inflammation of acute allergic rhinitis in a rat model. We observed that this population of cells inhibited sneezing, nose rubbing, and changes in the pathology of the nasal mucosa. Intriguingly, we observed that MSCs reduced the expression of interleukin 4, tumour necrosis factor alpha, and immunoglobulin E in the serum. Furthermore, MSCs reduced the expression of histamine and the recruitment of macrophages in the nasal mucosa of allergic rhinitis rats. We reasoned that the effect of MSCs on allergic rhinitis might be through its regulation of the secretion of related cytokines from macrophages during the process of acute allergic rhinitis. This work suggested that MSCs from the umbilical cords of humans could be used as a positive clinical therapy for the human disease. 相似文献