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131.
Acute liver failure (ALF) is an inflammation-mediated hepatocyte death process associated with ferroptosis. Avicularin (AL), a Chinese herbal medicine, exerts anti-inflammatory and antioxidative effects. However, the protective effect of AL and the mechanism on ALF have not been reported. Our in vivo results suggest that AL significantly alleviated lipopolysaccharide (LPS)/D-galactosamine (D-GalN)-induced hepatic pathological injury, liver enzymes, inflammatory cytokines, reactive oxygen species and iron levels and increased the antioxidant enzyme activities (malondialdehyde and glutathione). Our further in vitro experiments demonstrated that AL suppressed inflammatory response in LPS-stimulated RAW 264.7 cells via blocking the toll-like receptor 4 (TLR4)/myeloid differentiation protein-88 (MyD88)/nuclear factor kappa B (NF-κB) pathway. Moreover, AL attenuated ferroptosis in D-GalN-induced HepG2 cells by activating the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1)/glutathione peroxidase 4 (GPX4) pathway. Therefore, AL can alleviate inflammatory response and ferroptosis in LPS/D-GalN-induced ALF, and its protective effects are associated with blocking TLR4/MyD88/NF-κB pathway and activating Nrf2/HO-1/GPX4 pathway. Moreover, AL is a promising therapeutic option for ALF and should be clinically explored.  相似文献   
132.
从73个尖孢镰孢(Fusarium oxysporum)不同专化型菌株上获得684个硝酸盐营养突变株(nit mutant)。作相关氮源利用试验及亚硝酸反应后,鉴定出一新硝酸盐营养突变类型:亚硝酸盐还原酶结构基因类型,命名为nit8,占总突变株的6.7%。同时被鉴别的还有nit1、nit3和Nit M三种突变类型,它们分别占突变株总数的81.0%,3.8%和8.5%。此外,首次引入一种亚硝酸反应在这类研究中的应用,还提出了互补指数概念与公式来表示nit突变株营养体之间亲和的能力。  相似文献   
133.
In this work, binding interactions of artemisinin (ART) and dihydroartemisinin (DHA) with human serum albumin (HSA) and bovine serum albumin (BSA) were investigated thoroughly to illustrate the conformational variation of serum albumin. Experimental results indicated that ART and DHA bound strongly with the site I of serum albumins via hydrogen bond (H-bond) and van der Waals force and subsequently statically quenched the intrinsic fluorescence of serum albumins through concentration-dependent manner. The quenching abilities of two drugs on the intrinsic fluorescence of HSA were much higher than the quenching abilities of two drugs on the intrinsic fluorescence of BSA. Both ART and DHA, especially DHA, caused the conformational variation of serum albumins and reduced the α-helix structure content of serum albumins. DHA with hydrophilic hydroxyl group bound with HSA more strongly, suggesting the important roles of the chemical polarity and the hydrophilicity during the binding interactions of two drugs with serum albumins. These results reveal the molecular understanding of binding interactions between ART derivatives and serum albumins, providing vital information for the future application of ART derivatives in biological and clinical areas.  相似文献   
134.
Fang  Siyu  Li  Jie  Zheng  Wenfeng  Liu  Zhiyong  Feng  Hui  Zhang  Yun 《Protoplasma》2023,260(1):225-236

Isolated microspore culture has been implemented in breeding programs to produce doubled haploid (DH) lines and thus accelerates the breeding process. However, low microspore embryogenesis frequency in flowering Chinese cabbage remains a key obstacle to the practical application of this technique. This study aimed to establish an efficient microspore culture protocol for flowering Chinese cabbage that would be applied for heterosis breeding. Microspores of five genotypes, 19AY05, 19AY06, 19AY10, 19AY12, and 19AY15, were successfully induced to produce embryos in NLN-13 medium. Microspores of two genotypes, 19AY05 and 19AY15, were cultivated in NLN-13 medium supplemented with different concentrations (0, 0.01, 0.05, 0.1, or 0.2 mg·L−1) of compound sodium nitrophenol (sodium nitrophenol, 5-nitrophenol) to enhance microspore embryogenesis and plant regeneration without an intervening callus phase. The results showed that 0.05 ~ 0.1 mg· L−1 sodium nitrophenol and 0.01 ~ 0.2 mg· L−1 of 5-nitrophenol significantly promoted the induction of microspore embryogenesis of two genotypes, and the best concentrations required for different genotypes are different. Moreover, 0.1 mg· L−1 sodium nitrophenol can significantly increase the plant regeneration rate of the two genetypes. The 5-nitrophenol at 0.01 mg·L−1 significantly increased rate of embryos directly convert to plant in 19AY15. In addition, the average doubled haploid rates in the five genotypes were close to 63%. Horticultural traits of DH lines from 19AY05 were identified and all of them were self-incompatible lines. They showed a high uniformity and consistency that can be directly used for hybrid breeding. Furthermore, the hybrid combination was prepared with the selected DH lines and the Guangdong nucleus genic sterile line GMS019 to screen the excellent hybrid combination for the flowering Chinese cabbage breeding program. This method accelerates the application of microspore culture in hybrid breeding of flowering Chinese cabbage.

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135.
Different from the traditional knowledge about kelp, three sexual phenotypes (female, male, and monoecious) exist in the haploid gametophytes of Undaria pinnatifida. However, the sex-determining mechanisms remain unknown. Genetic linkage mapping is an efficient tool to identify sex-linked regions. In the present study, we resequenced a segregating gametophyte family based on the male genome of U. pinnatifida. A high-density genetic linkage map was constructed using 9887 SNPs, with an average distance of 0.41 cM between adjacent SNPs. On the basis of this genetic map and using the composite interval mapping method, we identified 62 SNPs significantly linked with the sexual phenotype. They were located at a position of 67.67 cM on the linkage group 23, corresponding to a physical range of 14.67 Mbp on the HiC_Scaffold_23 of the genome. Reanalysis of the previous specific length amplified fragment sequencing data according to the reference genome led to the identification of a sex-linked genomic region that encompassed the above-mentioned 14.67 Mbp region. Hence, this overlapped genomic range was likely the sex-determining region. Within this region, 129 genes were retrieved and 39 of them were annotated with explicit function, including the potential male sex-determining gene-encoding high mobility group (HMG) domain protein. Relative expression analysis of the HMG gene showed that its expression was higher in male gametophytes during the vegetative phase and monoecious gametophytes during both the vegetative and gametogenesis phases, but significantly lower in male gametophytes during the gametogenesis phase. These results provide a foundation for deciphering the sex-determining mechanism of U. pinnatifida.  相似文献   
136.
Gui  Runfei  Mo  Zhaowen  Zeng  Shan  Wen  Zhiqiang  Long  Weisi 《Journal of Plant Growth Regulation》2023,42(3):1604-1613

Compared with the standard method of manual fertilizer broadcasting (MFB), mechanized hill-drilling direct-seeding with deep application of slow-release nitrogen fertilizer (MHDDF) is an efficient method to integrate both fertilization and seeding. However, there are few studies that combine the use of slow-release fertilizer with MHDDF. We sought to explore the combined effect of MHDDF with slow-release fertilizer on rice yield and nitrogen, phosphorus, and potassium utilization, compared to MFB. We compared three different MHDDF methods (D30: 450 kg ha?1, D40: 600 kg ha?1, D50: 750 kg ha?1), with one MFB method (B50: 750 kg ha?1), and one control (CK: 0 kg ha?1). We found that the yield of all MHDDF method was higher than that of both the MFB method. Yield was the highest in the D50 treatment and was 14.14–46.03% higher than that in B50 treatment. Biomass accumulation, nutrient accumulation, and nutrient use efficiency were similarly higher in MHDDF method than both MFB and CK. Compared to B50, the D50 treatment increased nitrogen recovery efficiency by 170.53–231.50%, phosphorus recovery efficiency by 480.00–724.25%, and potassium recovery efficiency by 201.55–169.59%. Overall, we found that combining MHDDF with slow-release fertilizer was an effective method to increase rice yield and nutrient use efficiency compared with MFB.

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137.
催产时鳝卵磷酸酶活性的变化及其与排卵的关系   总被引:2,自引:0,他引:2  
本实验采用Gomori组织化学法和磷酸苯二钠法,分别检测黄鳝卵ALP、ACP的细胞定位和活性变化。结果表明,催产后72h,ALP活性显著高于临近注射时(Oh),催产后48h和96h(p<0.05);临产前(催产后96h),ACP活性极显著高于试验组其它各时程(p<0.01)。提示ALP和ACP活性增强与卵母细胞成熟、排放有直接关系。本研究为探索排卵机制提供资料。  相似文献   
138.
异育银鲫及其人工杂合种外源遗传物质的检测分析   总被引:22,自引:4,他引:18  
采用 DNA 杂交的方法,对异育银鲫及其人工杂合种进行了外源 DNA 的检测分析,发现两个雌核发育系的异育银鲫及其人工杂合种的 DNA 与红鲤 DNA 片段间的分子杂交均有阳性斑点出现,这表明,在异育银鲫及其人工杂合种产生过程中,父本(红鲤)的 DNA 片段的确可以随机地掺入到母本细胞的 DNA 中,从而产生了异精效应,使其子代生长加快,并出现父本性状。  相似文献   
139.
竹溪县现有种子植物127科483属863种。地理成分复杂,联系广泛,以温带成分占主导地位,占非世界分布属的64.83%,热带分布属则占29.39%,木本植物占种子植物总数的42.59%,主要植补类型计7个植补型组,10个植被型,49个联系。地处竹溪中南部的云雾溪是目前亚热带区域保存较为完整,具有多方面保护价值的综合区,建议辟为自然保护区。  相似文献   
140.
(Zn·Cd)S:Ag-KI催化的光合磷酸化   总被引:3,自引:0,他引:3  
以半导体材料(Zn·Cd)S:Ag-KI为催化剂,在普通卤钨灯光照射下,成功地模拟了光合作用的光合磷酸化.文章报导了光强、照光时间、ADP浓度、Pi浓度及催化剂量等对ATP合成的影响.在合适的条件下,ADP浓度为1×10~(-3)mmolL时转化率可达到4-6°.最后有一简单讨论.  相似文献   
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