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921.
Infants often experience complementary food-induced diarrhoea (CFID), which occurs when infants switch from breast milk to solid foods. The relative abundances of Prevotella and Rothia were higher in stools of infants with CFID, while the relative abundances of Enterococcus and Escherichia were higher in healthy infants. The abundance of Lactobacillus spp. normally found in breast milk fed to infants with CFID was significantly reduced, and Enterococcus spp. were less abundant when diarrhoea occurred. Furthermore, Lactobacillus and Enterococcus were present as shared bacteria in both mother and infant, and they were considered potential anti-CFID probiotics as their relative abundances in breast milk were negatively correlated to infant CFID. Kyoto encyclopedia of genes and genomes (KEGG) functional analysis showed that the function of amino acid metabolism differed between infants with CFID and healthy infants. Therefore, CFID might be related to the decomposition of proteins in food supplements. The screening revealed seven hydrolytic casein and five hydrolytic casein and rice protein isolates from 320 suspected Lactobacillus and Enterococcus isolates. The animal experiments demonstrated that a mixture of five isolates effectively hydrolysed the casein and rice protein and prevented diarrhoea in young rats. Thus, the occurrence of CFID was found to be closely related to the intestinal and breast milk microbiota, and bacteria that could assist in the digestion of cereal proteins were involved in CFID.  相似文献   
922.
923.
Shan  Mingqiu  Jiang  Yulan  Fu  Yuanyuan  Zhou  Yongyi  Lu  Zhihui  Yu  Sheng  Yan  Hui  Liu  Chanchan  Chen  Peidong  Bao  Beihua  Zhang  Li  Wu  Qinan 《Phytochemistry Reviews》2021,20(5):991-1012
Phytochemistry Reviews - Nepeta tenuifolia (N. tenuifolia) is a common aromatic herb that is widespread in East Asia. The aerial parts and spikes can be used as the traditional phytomedicines for...  相似文献   
924.
Zhou  Ting  Gou  Xinyu  Xu  Wei  Li  Yong  Zhai  Xiang  Li  Hongjian  Wang  Lingling 《Plasmonics (Norwell, Mass.)》2021,16(2):323-332

We propose a dynamically tunable surface plasmon polaritons (SPPs) waveguide system based on bulk Dirac semimetals (BDS) containing only a side-coupled T-shaped cavity. Plasmon-induced transparency (PIT) is achieved in the terahertz band by introducing a position offset. We have analytically investigated the spectral characteristics of PIT in this system, indicating that the larger the position offset, the higher the peak of the PIT window. The spectrum responses of PIT system can be flexibly regulated via transforming the geometric parameters of the structure. At the same time, it is particularly sensitive to the refractive index of the surrounding medium, which is promising for sensing devices. In addition, the resonance frequency and peak transmission can be actively adjusted by controlling the Fermi energy of the BDS without reconstructing the geometric structure. Moreover, the optical delay time near the PIT peak reaches 11.001 ps, which has good slow-light characteristics and is a candidate in the field of slow-light equipment. The structure we designed may have potential application value in the design of SPPs light-guide devices.

  相似文献   
925.
926.
我国是世界上植物多样性最丰富的国家之一, 1999年发布的《国家重点保护野生植物名录》(下称《名录》(第一批))明确了国家重点保护野生植物的范围, 为依法强化保护、规范无序开发利用、提高公众保护意识奠定了基础。20多年来, 我国野生植物多样性保护形势发生了很大变化, 需要对《名录》进行调整。2018年, 国家林业和草原局、农业农村部启动《名录》调整工作, 物种的遴选遵循了5条基本原则和4条补充性原则, 这些原则主要涉及中国珍稀濒危物种, 具有重要经济、文化、科研、生态等价值物种的入选以及部分物种的排除。经国务院批准, 2021年9月7日, 国家林业和草原局、农业农村部发布了调整后的《名录》, 包括真菌类、藻类、苔藓、石松类和蕨类植物、裸子植物和被子植物, 共计约1,101种(455种和40类)野生植物列入其中。本文简要介绍了《名录》调整的必要性、原则和程序及调整后的情况。  相似文献   
927.
目的探究葛根芩连汤对泄泻肠道湿热证小鼠肠道双糖酶活性的影响。方法采用“高糖高脂+高温高湿+白酒复合灌胃冰水”的方法制备泄泻肠道湿热证小鼠模型,并运用葛根芩连汤进行干预治疗。分别在干预的第0、2、4、6天无菌采集各组小鼠肠黏膜,运用DNS法测定蔗糖酶活性,ONPG法测定乳糖酶活性,观察葛根芩连汤对泄泻肠道湿热证小鼠肠道双糖酶活性的影响。结果经肠道湿热泄泻造模后,小鼠肠道前段和后段黏膜的乳糖酶和蔗糖酶活性均显著下降,与正常组小鼠相比差异有统计学意义(均P<0.01)。随着治疗时间的延长,治疗组小鼠肠道乳糖酶和蔗糖酶活性与正常组相比有显著的提高(均P<0.05),治疗6 d后,肠道前段黏膜蔗糖酶和乳糖酶活性恢复至正常组水平(P>0.05)。肠道后段乳糖酶活性在第4天时最高,后段黏膜蔗糖酶活性在第6天时最高,与正常组和自愈组相比差异有统计学意义(均P<0.05)。结论泄泻肠道湿热证造模使小鼠肠道黏膜蔗糖酶、乳糖酶等双糖酶的活性显著下降,葛根芩连汤能调节泄泻肠道湿热证小鼠肠道黏膜乳糖酶和蔗糖酶的活性,从而发挥治疗泄泻肠道湿热证的疗效。  相似文献   
928.
Zhou  Jingyi  Shi  Yingying  Miao  Li  Zhang  Chunyan  Liu  Yongjuan 《International microbiology》2021,24(3):291-299
International Microbiology - Enterovirus A71 (EV-A71) is an important pathogen of severe hand, foot, and mouth disease (HFMD) in young children. This study aimed to retrospectively analyze the...  相似文献   
929.
Journal of Physiology and Biochemistry - Dexamethasone augments mitochondrial protein abundance. The translocase of the outer membrane (Tom) of mitochondria plays a major role in importing largely...  相似文献   
930.
Composting is widely used to reduce the abundance of antibiotic resistance genes (ARGs) in solid waste. While ARG dynamics have been extensively investigated during composting, the fate and abundance of residual ARGs during the storage remain unexplored. Here, we tested experimentally how ARG and mobile genetic element (MGE) abundances change during compost storage using metagenomics, quantitative PCR and direct culturing. We found that 43.8% of ARGs and 39.9% of MGEs quickly recovered already during the first week of storage. This rebound effect was mainly driven by the regrowth of indigenous, antibiotic-resistant bacteria that survived the composting. Bacterial transmission from the surrounding air had a much smaller effect, being most evident as MGE rebound during the later stages of storage. While hyperthermophilic composting was more efficient at reducing the relative abundance of ARGs and MGEs, relatively greater ARG rebound was observed during the storage of hyperthermophilic compost, exceeding the initial levels of untreated sewage sludge. Our study reveals that residual ARGs and MGEs left in the treated compost can quickly rebound during the storage via airborne introduction and regrowth of surviving bacteria, highlighting the need to develop better storage strategies to prevent the rebound of ARGs and MGEs after composting.  相似文献   
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