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101.
背景 冷过敏是炎性痛和神经病理性疼痛的一个常见症状,其内在机制尚不清楚. 目的 阐明瞬时受体电位通道A1 (transient receptor potential cation channel,subfamily A,member 1,TRPA1)和瞬时受体电位通道M8(transient receptor potential melastatin 8,TRPM8)参与冷过敏的机制. 内容 综述TRPA1和TRPM8的分子结构和门控机制及其在有害的冷、炎性痛和神经病理性疼痛的冷过敏形成、维持中的作用等方面的研究. 趋向 深入研究TRPA1和TRPM8在冷过敏发生中的作用,有助于阐明冷过敏的机制,并为开发拮抗剂提供理论依据. 相似文献
102.
Keigo Murakami Yasuhiro Nakamura Yasunori Miyasaka Toshinobu Sato Naoki Kawagishi Hironobu Sasano 《Pathology international》2020,70(5):270-279
Intestinal necrosis associated with cation exchange resin (CER) is considered related to sorbitol, but it has been reported even in patients receiving CER alone. This study was performed to identify the risk factors of CER‐related intestinal necrosis. The pathological database of 61 end‐stage renal disease patients with surgical intervention for intestinal perforation was reviewed. The correlations between CER treatment and clinicopathological factors were studied among three groups: (i) patients administered CER and with CER at the perforation site (n = 23), (ii) patients administered CER with undetected CER at the perforation site (n = 12) and (iii) patients not administered CER (n = 26). The majority of the perforation site in group 1 was in the sigmoid colon (82.6%) with significantly higher average age and more frequent CER adhesion rates to the mucosa around the perforation site than group 2. The laxative administration rate in group 1 was significantly higher than group 3 and tended to be higher than group 2. The incidence of CER‐related intestinal necrosis was estimated at 0.57%. CER should be used with extreme caution in elderly patients with passage disturbance. 相似文献
103.
Superoxide dismutases (SODs) are ubiquitous family of metalloenzymes involved in protecting organisms from excess reactive oxygen species damage. In this paper, a novel intracellular Cu/ZnSOD from Sepiella maindroni (designated as SmSOD) was identified and characterized. The full-length cDNA sequence of SmSOD (GenBank accession No. KF908850) was 709 bp containing an open reading frame (ORF) of 459 bp, encoding 153 amino acid residues peptide with predicted pI/MW (6.02/15.75 kDa), a 131 bp-5′- and 116 bp-3′- untranslated region (UTR). BLASTn analysis and phylogenetic relationship strongly suggested that the sequence shared high similarity with known Cu/Zn SODs. Several highly conserved motifs, including two typical Cu/Zn SOD family domains, two conserved Cu-/Zn-binding sites (H-47, H-49, H-64, H-120 for Cu binding, and H-64, H-72, H-81, D-84 for Zn binding) and intracellular disulfide bond (C-58 and C-146), were also identified in SmSOD. Time-dependent mRNA expression of SmSOD in hepatopancreas was recorded by quantitative real-time RT-PCR after Vibrio harveyi injection and Cd2+ exposure. The results indicated that SmSOD was an acute-phase protein involved in the immune responses against pathogens and biological indicator for metal contaminants in aquatic environment. 相似文献
104.
Katrin Bäsell Andreas Otto Sabryna Junker Daniela Zühlke Gerd-Martin Rappen Sabrina Schmidt Christian Hentschker Boris Macek Knut Ohlsen Michael Hecker Dörte Becher 《International journal of medical microbiology : IJMM》2014,304(2):121-132
Phosphorylation events on proteins during growth and stress/starvation can represent crucial regulation processes inside the bacterial cell. Therefore, serine, threonine and tyrosine phosphorylation patterns were analyzed by two powerful complementary proteomic methods for the human pathogen Staphylococcus aureus. Using 2D-gel analysis with a phosphosensitive stain (Pro-Q Diamond) and gel-free titanium dioxide based phosphopeptide enrichment, 103 putative phosphorylated proteins with successfully mapped 68 different phosphorylation sites were found in the soluble proteome of S. aureus. Additionally, in a proof of concept study, 8 proteins phosphorylated on arginine residues have been identified. Most important for functional analyses of S. aureus, proteins related to pathogenicity and virulence were found to be phosphorylated: the virulence regulator SarA, the potential antimicrobial target FbaA and the elastin-binding protein EbpS. Besides newly identified phosphorylation sites we compared our dataset with existing data from literature and subsequent experiments revealed additional phosphorylation events on highly conserved localizations in FbaA. Differential analysis of phosphorylation signals on the 2D-gels showed significant changes in phosphorylation under different physiological conditions for 10 proteins. Among these, we were able to detect newly appearing signals for phosphorylated isoforms of FdaB and HchA under nitrosative stress conditions. 相似文献
105.
越来越多的研究结果表明,Cajal间质细胞是胃肠道平滑肌慢波电位和自发性节律性收缩活动的起搏细胞.关于Cajal间质细胞起搏电流产生机制的研究近来进展很快,但仍存在一些分歧.本文就目前关于起搏电流的产生及传播机制的研究进展作一综述. 相似文献
106.
107.
胰腺癌中表观遗传修饰研究进展 总被引:1,自引:0,他引:1
胰腺癌的形成受遗传学和表现遗传修饰的影响.基因突变或缺失(遗传学)参与肿瘤的形成,DNA甲基化、组蛋白修饰和RNA干扰等(表观遗传修饰)调节基因表达.随着基因组筛选技术的发展,胰液中DNA甲基化定量检测是诊断胰腺癌的潜在工具,以DNA甲基化和组蛋白乙酰化为基础的表观遗传学是胰腺癌治疗领域中的新靶点.本文对胰腺癌发生发展过程中出现的表遗传修饰异常,以及其生物学和临床意义前景作一介绍. 相似文献
108.
Rolf W. Sparidans Jan den Hartigh Pieter Vermeij 《Journal of pharmaceutical and biomedical analysis》1995,13(12):1545-1550
An ion-exchange chromatographic method using an anion-exchange column was developed for the analysis of a number of bisphosphonates. The bisphosphonates were in-line complexed by copper(II) ions and added to the acidic eluent, to yield an UV-absorbing complex. Chromatographic parameters were studied for eight different bisphosphonates, particularly amino-1-hydroxyalkyl-1,1-bisphosphonates; special attention was paid to the relationship between retention and complex formation. The method was applied to the quality control of pamidronate injection concentrate and olpadronate tablets. The lower detection limit was 8 ng of disodium pamidronate, and the inter-assay precision was 1.0% for both pamidronate and olpadronate standard solutions and 1.8% for a 3 mg ml−1 disodium pamidronate injection concentrate. The method was compared with a previously described ion-exchange chromatographic method with conductivity detection, without copper(II) ions in the eluent. 相似文献
109.
110.