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51.
Bipolar disorder is a decidedly heterogeneous and multifactorial disease, with significant psychosocial and medical disease burden. Much difficulty has been encountered in developing novel therapeutics and objective biomarkers for clinical use in this population. In that regard, gut-microbial homeostasis appears to modulate several key pathways relevant to a variety of psychiatric, metabolic, and inflammatory disorders. Microbial impact on immune, endocrine, endocannabinoid, kynurenine, and other pathways are discussed throughout this review. Emphasis is placed on this system’s relevance to current pharmacology, diet, and comorbid illness in bipolar disorder. Despite the high level of optimism promoted in many reviews on this topic, substantial obstacles exist before any microbiome-related findings can provide meaningful clinical utility. Beyond a comprehensive overview of pathophysiology, this review hopes to highlight several key areas where progress is needed. As well, novel microbiome-associated suggestions are presented for future research.  相似文献   
52.
张福松 《环境卫生工程》2009,17(3):17-18,21
结合火力发电厂采用双膜法对循环排污水预除盐回用于锅炉补给水的工程实例,通过实验取得系统运行数据。结果表明:将微滤作为反渗透的预处理工艺能保证反渗透对进水水质的要求,并能取得良好的经济和社会效益。  相似文献   
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The paper summarizes the results of inhalation toxicology studies associated with para-aramid (p-aramid) fibrils. The review is subdivided into two categories: the results of inhalation toxicity studies and mechanistic inhalation studies. Keratin-associated lesions were observed in the lungs of female rats following chronic exposure to high concentrations of p-aramid. These lesions were originally interpreted as cystic keratinizing squamous cell carcinomas (CKSCC). In recent years, this keratinizing lesion has been observed in the lungs of rats with greater regularity in numerous chronic inhalation studies following exposures to a variety of dusts. In an attempt to reach a consensus on an appropriate diagnosis for this lesion, an international panel of pathologists was convened to evaluate the morphological aspects of this lesion. The panel considered that the most appropriate diagnosis for this lesion was ‘proliferative keratin cyst’ (PKC). the biological potential of the PKC remains controversial, but it appears to be unique to the rat species and has little relevance for humans. Mechanistic studies with p-aramid have demonstrated that acute inhalation of high concentrations of fibrils produces a potent but transient pulmonary inflammatory and cell labelling response. The inhaled fibrils have low durability in the lungs of rats as evidenced by a progressive decrease in median fibre lengths with increasing residence time in the lung. In contrast, in a comparative study, size-separated chrysotile asbestos produced a sustained increase over controls in cellular proliferation responses of terminal airways, parenchyma, subpleural and mesothelial regions. In addition, while the short fibres were cleared at a normal or rapid rate, the long (i.e. > 5 μm) chrysotile fibres were retained in the lung or cleared at a slow rate, suggesting that this subpopulation of fibres is durable in the lungs of exposed rats. These results point out the differences in the lung responses between p-aramid fibrils when compared to chrysotile asbestos fibres, namely, that chrysotile produced enhanced and sustained cell proliferation responses, and that the long chrysotile fibres were retained in the lungs of exposed rats.  相似文献   
55.
Since PTP1B enzyme was discovered in 1988, it has captured the research community’s attention. This landmark discovery has stimulated numerous research studies on a variety of human diseases, including cancer, inflammation, and diabetes. Tremendous progress has been made in finding PTP1B inhibitors and exploring PTP1B regulatory mechanisms. This review investigates for the natural PTP1B inhibitors, and focuses on the common characteristics of the discovered structures and structure–activity relationships. To facilitate understanding, all the natural compounds are here divided into five different classes (fatty acids, phenolics, terpenoids, steroids, and alkaloids), according to their skeletons. These PTP1B inhibitors of scaffold structures could serve as a theoretical basis for new concept drug discovery and design.  相似文献   
56.
三种红树林内生真菌的环肽类次级代谢产物的研究   总被引:1,自引:0,他引:1  
郭志勇  黄忠京  温露  万乔  刘凡  佘志刚  林永成  周世宁 《中药材》2007,30(12):1526-1529
从三种红树林内生真菌Paecilomyces sp.(treel-7),4557,ZZF65中分到九个环肽类的次级代谢产物,分别是viscumamide(1),cyclo(Pro-Iso)(2),cyclo(Phe-Gly)(3),cyclo(Phe-Ana)(4),cyclo(Gly-Pro)(5),cyclo(Gly-Leu)(6),cyclo(Trp-Ana)(7),neoechinulin A(8),cyclo(Pro-Thr)(9)。其中化合物1,7,8,9是首次从海洋真菌中分离得到。  相似文献   
57.
To evaluate the removal of potassium cyanide (KCN) and its toxicity in algae, an initial comprehensive analysis was performed with Chlorella vulgaris. The algae showed potential removal capability for KCN, with the maximal removal rate of 61%. Moreover, effects of KCN on growth, cellular morphology and antioxidant defense system of C. vulgaris were evaluated. Cell number and chlorophyll a content decreased in most cases, with the maximal inhibition rates of 48% and 99%, respectively. The 100 mg L??1 KCN seriously damaged the algal cell membrane. Additionally, activity of superoxide dismutase (SOD) was promoted by KCN exposure among 0.1–50 mg L??1 and inhibited by 100 mg L??1 KCN, while the malondialdehyde (MDA) content gradually decreased in C. vulgaris with increasing exposure concentration compared to the control. The present study reveals that C. vulgaris is useful in bio-treatment of cyanide-contaminated aquatic ecosystem, except in high concentrations which would cause overwhelming effects.  相似文献   
58.
Cancer can invade or spread to almost all parts of the body. The increasing morbidity and high mortality of cancer create a great demand for the development of novel anticancer drugs. Coumarin derivatives are ubiquitous in nature and can readily interact with diverse enzymes and receptors in cancer cells via weak bond interactions; hence, coumarin is a highly privileged pharmacophore for the development of novel anticancer agents. This review will focus on the recent development of coumarin hybrids as potential anticancer agents covering articles published from 2019 to 2020.  相似文献   
59.
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