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排序方式: 共有140条查询结果,搜索用时 15 毫秒
1.
为了对比野生与种植青海川西獐牙菜中微量元素的变化,分别采集野生川西獐牙菜与种植青海川西獐牙菜种子采收前后的全植株,采用原子吸收光谱仪测定了其铜、锌、铁、锰、钴等微量元素含量。结果表明,野生川西獐牙菜较种植青海川西獐牙菜中微量元素含量高,种植川西獐牙菜在成熟种子采收后较采收前(花果期)铁、锰、钴、锌等元素含量高。 相似文献
2.
《Arabian Journal of Chemistry》2022,15(4):103712
Although recent decades have witnessed the synthesis of 1,3,4-thiadiazoles via phosphorus POCl3-promoted cyclization reaction, simultaneous access to 2-amino-1,3,4-thiadiazole and 2-amino-1,3,4-oxadiazole analogs remains unexpected and elusive. Herein, a detailed regiocontrolled synthesis of 2-amino-1,3,4-thiadiazoles in good to high yields with good regioselectivities from readily available thiosemicarbazides using POCl3 was disclosed. Meantime, to establish a comprehensive structure–activity relationship, 2-amino-1,3,4-oxadiazole derivatives as single regioisomers were prepared via EDCI·HCl-triggered cyclization of the thiosemicarbazide intermediates. The in vitro anti-influenza assays proved that the selected compounds with the pyrazine/pyridine ring exhibited certain inhibitory activities against influenza A virus strains A/HK/68 (H3N2) and A/PR/8/34 (H1N1) in MDCK cells. Among them, N-(adamantan-1-yl)-5-(5-(azepan-1-yl)pyrazin-2-yl)-1,3,4-thiadiazol-2-amine (4j) was the most active compound, and exhibited favorable activity with EC50 values of 3.5 μM and 7.5 μM, respectively. In addition, the molecular docking results explained the reason why compound 4j had dual inhibitory activity and revealed the reasonable binding mode of this compound with the M2-S31N and M2-WT ion channels. This compound had the potential to be further developed as an anti-influenza drug. 相似文献
3.
We study wild embeddings of S
1 in S
n which are tame in a sense introduced by Quinn. We show that if is a finitely presented group with H
1()=H
2()=0, then any finiteness obstruction K
0() can be realized on the complement of such an embedded S
1. We also realize trivially symmetric K
–1() obstructions on the complements of such embeddings. For trivially symmetric , the embeddings constructed are shown to be isotopy homogeneous. 相似文献
4.
Mushrooms, the fruiting bodies of fungi, are known for a long time in different cultures around the world to possess medicinal properties and are used to treat various human diseases. Mushrooms that are parts of traditional medicine in Asia had been extensively studied and this has led to identification of their bioactive ingredients. North America, while home to one of the world’s largest and diverse ecological systems, has not subjected its natural resources especially its diverse array of mushroom species for bioprospecting purposes: Are mushrooms native to North America a good source for drug discovery? In this review, we compile all the published studies up to September 2020 on the bioprospecting of North American mushrooms. Out of the 79 species that have been investigated for medicinal properties, 48 species (60%) have bioactivities that have not been previously reported. For a mere 16 selected species, 17 new bioactive compounds (10 small molecules, six polysaccharides and one protein) have already been isolated. The results from our literature search suggest that mushrooms native to North America are indeed a good source for drug discovery. 相似文献
5.
Chul-Joong Kim Hyeon-Yeol Ryu Somin Lee Han-Joo Lee Yoon-Soek Chun Jong-Kyu Kim Chang-Yeon Yu Bimal Kumar Ghimire Jae-Geun Lee 《Molecules (Basel, Switzerland)》2021,26(10)
Wild ginseng has better pharmacological effects than cultivated ginseng. However, its industrialization is limited by the inability to grow wild ginseng on a large scale. Herein, we demonstrate how to optimize ginseng production through cultivation, and how to enhance the concentrations of specific ginsenosides through fermentation. In the study, we also evaluated the ability of fermented cultured wild ginseng root extract (HLJG0701-β) to inhibit acetylcholinesterase (AChE), as well as its neuroprotective effects and antioxidant activity. In in vitro tests, HLJG0701-β inhibited AChE activity and exerted neuroprotective and antioxidant effects (showing increased catalyst activity but decreased reactive oxygen species concentration). In in vivo tests, after HLJG0701-β was orally administered at doses of 0, 125, 250, and 500 mg/kg in an animal model of memory impairment, behavioral evaluation (Morris water maze test and Y-maze task test) was performed. The levels of AChE, acetylcholine (ACh), blood catalase (CAT), and malondialdehyde (MDA) in brain tissues were measured. The results showed that HLJG0701-β produced the best results at a dose of 250 mg/kg or more. The neuroprotective mechanism of HLJG0701-β was determined to involve the inhibition of AChE activity and a decrease in oxidative stress. In summary, both in vitro and in vivo tests confirmed that HJG0701-β administration can lead to memory improvement. 相似文献
6.
RENÉ A. SALINAS WILLIAM H. STIVER JOSEPH L. CORN SUZANNE LENHART CHARLES COLLINS MARGUERITE MADDEN KURT C. VERCAUTEREN BRANDON B. SCHMIT ELLEN KASARI AGRICOLA ODOI GRAHAM HICKLING HAMISH MCCALLUM 《Natural Resource Modeling》2015,28(1):18-36
The expansion of feral hog (Sus scrofa) populations in the United States has resulted in increased efforts to develop and implement control strategies designed to minimize the impacts done by this invasive species. We describe an individual‐based model for feral hogs in Great Smoky Mountains National Park (GSMNP). The objectives of the model are to provide an understanding of the population dynamics of this feral hog population and to determine the efficacy of the annual harvest as a population control method. Results suggest that the dynamics of the population are driven by fall hard mast production and the GSMNP harvests currently limit growth of the population, but these control efforts have not reduced the population. 相似文献
7.
Elisa Roda Fabrizio De Luca Carlo Alessandro Locatelli Daniela Ratto Carmine Di Iorio Elena Savino Maria Grazia Bottone Paola Rossi 《Molecules (Basel, Switzerland)》2020,25(22)
Bioactive metabolites isolated from medicinal mushrooms (MM) used as supportive treatment in conventional oncology have recently gained interest. Acting as anticancer agents, they interfere with tumor cells and microenvironment (TME), disturbing cancer development/progression. Nonetheless, their action mechanisms still need to be elucidated. Recently, using a 4T1 triple-negative mouse BC model, we demonstrated that supplementation with Micotherapy U-Care, a MM blend, produced a striking reduction of lung metastases density/number, paralleled by decreased inflammation and oxidative stress both in TME and metastases, together with QoL amelioration. We hypothesized that these effects could be due to either a direct anticancer effect and/or to a secondary/indirect impact of Micotherapy U-Care on systemic inflammation/immunomodulation. To address this question, we presently focused on apoptosis/proliferation, investigating specific molecules, i.e., PARP1, p53, BAX, Bcl2, and PCNA, whose critical role in BC is well recognized. We revealed that Micotherapy U-Care is effective to influence balance between cell death and proliferation, which appeared strictly interconnected and inversely related (p53/Bax vs. Bcl2/PARP1/PCNA expression trends). MM blend displayed a direct effect, with different efficacy extent on cancer cells and TME, forcing tumor cells to apoptosis. Yet again, this study supports the potential of MM extracts, as adjuvant supplement in the TNBC management. 相似文献
8.
Annalisa Maruca Roberta Rocca Raffaella Catalano Francesco Mesiti Giosu Costa Delia Lanzillotta Alessandro Salatino Francesco Ortuso Francesco Trapasso Stefano Alcaro Anna Artese 《Molecules (Basel, Switzerland)》2020,25(23)
Mushrooms can be considered a valuable source of natural bioactive compounds with potential polypharmacological effects due to their proven antimicrobial, antiviral, antitumor, and antioxidant activities. In order to identify new potential anticancer compounds, an in-house chemical database of molecules extracted from both edible and non-edible fungal species was employed in a virtual screening against the isoform 7 of the Histone deacetylase (HDAC). This target is known to be implicated in different cancer processes, and in particular in both breast and ovarian tumors. In this work, we proposed the ibotenic acid as lead compound for the development of novel HDAC7 inhibitors, due to its antiproliferative activity in human breast cancer cells (MCF-7). These promising results represent the starting point for the discovery and the optimization of new HDAC7 inhibitors and highlight the interesting opportunity to apply the “drug repositioning” paradigm also to natural compounds deriving from mushrooms. 相似文献
9.
10.
基于曲线拟合的形态相似鹅膏菌的傅里叶变换红外光谱研究 总被引:8,自引:0,他引:8
利用傅里叶变换红外光谱仪测试了形态相似的灰疣鹅膏菌、灰绒鹅膏菌和灰褶鹅膏菌的光谱,结果显示,它们的傅里叶变换红外光谱主要由蛋白质和多糖的振动吸收带组成,其蛋白质的吸收频率略有差。选择酰胺I带(中心频率1647cm-1)进行傅里叶自去卷积和曲线拟合处理后3种鹅膏菌中蛋白质在酰胺I带的吸收峰都由12个子峰叠加而成,其中在无序(1650cm-1)、α螺旋(1658cm-1)和β转角结构(1666cm-1)的振动吸收峰上,灰褶鹅膏菌吸收峰的面积百分比分别是20.98%、4.47%和17.14%,明显地区别于其它两种鹅膏菌(灰疣鹅膏菌:10.26%、12.58%和7.71%;灰绒鹅膏菌:14.33%、9.76%和8.83%)。在1683cm-1处的β转角吸收峰上,灰绒鹅膏菌吸收峰的面积百分比是1.92%,明显小于其它两种鹅膏菌(灰疣鹅膏菌:8.03%;灰褶鹅膏菌:6.65%)。研究表明:傅里叶变换红外光谱技术能提供大型真菌所含蛋白质二级结构信息。 相似文献