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排序方式: 共有750条查询结果,搜索用时 15 毫秒
731.
732.
Jennifer Trox Vellingiri Vadivel Walter Vetter Wolfgang Stuetz Dietmar R. Kammerer Reinhold Carle Veronika Scherbaum Ute Gola Donatus Nohr Hans Konrad Biesalski 《Food chemistry》2011
Catechins in testa and bioactive compounds in testa-free and testa-containing kernels of cashew nuts were analysed. The cashew nut testa contained (+)-catechin and (−)-epicatechin with concentrations of 5.70 and 4.46 g per kg DM, respectively. Testa-containing kernels revealed significantly higher levels of β-carotene (218 vs. 89.6 μg/kg DM), lutein (525 vs. 292 μg/kg DM), and α-tocopherol (10.1 vs. 2.4 mg/kg DM), similar amounts of zeaxanthin (7.0 vs. 7.1 μg/kg DM), γ-tocopherol (10.6 vs. 10.1 mg/kg DM), stearic acid (41 vs. 43 g/kg DM), oleic acid (214 vs. 219 g/kg DM) and linoleic acid (69 vs. 62 g/kg DM), but a lower concentration of thiamine (3.0 vs. 10.7 mg/kg DM) in comparison to testa-free samples. The testa-containing kernels provide high amounts of catechins and higher concentrations of β-carotene, lutein and α-tocopherol than do testa-free cashew nut kernels. This could have potential health benefits for consumers. 相似文献
733.
Yixuan Ma Sina Sender Anett Sekora Weibo Kong Peter Bauer Najim Ameziane Ruslan Al-Ali Susann Krake Mandy Radefeldt Frank Ulrich Weiss Markus M. Lerch Alisha Parveen Dietmar Zechner Christian Junghanss Hugo Murua Escobar 《International journal of molecular sciences》2022,23(8)
The aberrant activation of the phosphoinositide 3-kinase (PI3K)/ protein kinase B (AKT) pathway is common in pancreatic ductal adenocarcinomas (PDAC). The application of inhibitors against PI3K and AKT has been considered as a therapeutic option. We investigated PDAC cell lines exposed to increasing concentrations of MK-2206 (an AKT1/2/3 inhibitor) and Buparlisib (a pan-PI3K inhibitor). Cell proliferation, metabolic activity, biomass, and apoptosis/necrosis were evaluated. Further, whole-exome sequencing (WES) and RNA sequencing (RNA-seq) were performed to analyze the recurrent aberrations and expression profiles of the inhibitor target genes and the genes frequently mutated in PDAC (Kirsten rat sarcoma virus (KRAS), Tumor protein p53 (TP53)). MK-2206 and Buparlisib demonstrated pronounced cytotoxic effects and limited cell-line-specific effects in cell death induction. WES revealed two sequence variants within the direct target genes (PIK3CA c.1143C > G in Colo357 and PIK3CD c.2480C > G in Capan-1), but a direct link to the Buparlisib response was not observed. RNA-seq demonstrated that the expression level of the inhibitor target genes did not affect the efficacy of the corresponding inhibitors. Moreover, increased resistance to MK-2206 was observed in the analyzed cell lines carrying a KRAS variant. Further, increased resistance to both inhibitors was observed in SU.86.86 carrying two TP53 missense variants. Additionally, the presence of the PIK3CA c.1143C > G in KRAS-variant-carrying cell lines was observed to correlate with increased sensitivity to Buparlisib. In conclusion, the present study reveals the distinct antitumor effects of PI3K/AKT pathway inhibitors against PDAC cell lines. Aberrations in specific target genes, as well as KRAS and TP53, individually or together, affect the efficacy of the two PI3K/AKT pathway inhibitors. 相似文献
734.
Temporal and spatial distributions of phosphine in Taihu Lake, China 总被引:19,自引:0,他引:19
Niu X Geng J Wang X Wang C Gu X Edwards M Glindemann D 《The Science of the total environment》2004,323(1-3):169-178
Phosphine is a natural gaseous carrier of phosphorus in its geochemical cycles, and it might be of importance to the phosphorus balance of eutrophic lakes. Phosphine concentration levels in Taihu Lake, a typical shallow eutrophic lake in China, were intensely investigated in this work. Results show that in the period of 2002 the variation of phosphine concentration in the atmosphere near Taihu Lake is significant, with a maximum value 2.85 pg/l. Concurrent sampling of phosphine in surface and bottom water of the lake had no distinct change. The mean concentration of phosphine in the water ranged from 1.92 to 3.01 pg/l. Approximately 84-90% of the phosphine was removed from lake water during passage of the sample through a 0.45 microm pore size filter, i.e. the average phosphine concentrations of filtered lake water in all sampling locations were from 0.37 to 0.40 pg/l with the highest value 0.73 pg/l and the lowest 0.08 pg/l, whereas phosphine concentrations in unfiltered samples were 5-9 times higher. Phosphine levels in lake sediments were positively correlated with different contamination of the samples. The concentration levels of phosphine were also higher in severe polluted sites. The local average values of the phosphine concentrations were from 21550 to 563,100 pg/kg. Its highest value was 919,238 pg/kg at 6# site (Zhihu harbor), a severely polluted sampling site. 相似文献
735.
Carmen Ranftler Andreas Rhrich Andreas Sparer Cornelius Tschegg Dietmar Nagl 《International journal of molecular sciences》2022,23(9)
Various gluten-related diseases (celiac disease, wheat allergy, gluten sensitivity) are known and their incidence is growing. Gluten is a specific type of plant storage protein that can impair the health of gluten-prone persons following consumption, depending on the origin. The most severe effects are induced by wheat, barley, and rye. The only treatment is based on the absolute avoidance of those foods, as even traces might have severe effects on human well-being. With the goal of binding gluten impurities after ingestion, an in vitro setting was created. A special processed kind of zeolite, purified clinoptilolite-tuff (PCT), was implemented as an adsorber of gluten derived from different origins. Zeolites are known for their excellent sorption capacities and their applications in humans and animals have been studied for a long time. Tests were also performed in artificial gastric and intestinal fluids, and the adsorption capacity was determined via a certified validated method (ELISA). Depending on the kind of gluten source, 80–130 µg/mg of gluten were bound onto PCT. Hence, purified clinoptilolite-tuff, which was successfully tested for wheat, barley, and rye, proved to be suitable for the adsorption of gluten originating from different kinds of crops. This result might form the basis for an expedient human study in the future. 相似文献
736.
Manfred Schulz Gerd West Uta Müller Dietmar Henke 《Advanced Synthesis \u0026amp; Catalysis》1976,318(6):946-954
Photochemical Reactions of 3-Pyrazolidone Betains. VI. Influence of Substituents on Photochemical Diaziridine Formation from 3-Pyrazolidone Azomethinimines UV-irradiation of 3-pyrazolidone azomethinimines 1a–g in methanol as a solvent produces 40–92% yields of the corresponding 1-(methoxycarbonylethyl)-3-aryl-diaziridines 3a–g . The formation of these products occurs by ring opening of the bicyclic diaziridines 2a–g primarily formed. Although the bicyclic diaziridines 2h and 2i are formed on UV-irradiation in methanol, the betains 1h and 1i do not yield the corresponding diaziridine esters 3 . Kinetical investigations of the acid catalyzed re-formation of the betaines 1a, c, h , and i from the corresponding bicyclic diaziridines show that the basicity of the diaziridine ring in 2 , influenced by substituents in the phenyl ring, is responsible for the re-formation to 1 and the reaction to 3 , respectively. In contrast to the behaviour of the other betains 1 , compound 1j does not react photochemically to yield the bicyclic diaziridine 2j . This shows that an extension of the 4-electron system of the dipolaric azomethinimine group in 1 is necessary for the photochemical cyclization to diaziridines 2 . 相似文献
737.
Guerguerian G Elhordoy F Pereyra CJ Marotti RE Martín F Leinen D Ramos-Barrado JR Dalchiele EA 《Nanotechnology》2011,22(50):505401
ZnO/CdS core/shell nanorod arrays were fabricated by a two-step method. Single-crystalline ZnO nanorod arrays were first electrochemically grown on SnO(2):F (FTO) glass substrates. Then, CdS nanocrystals were deposited onto the ZnO nanorods, using the successive ion layer adsorption and reaction (SILAR) technique, to form core/shell nanocable architectures. Structural, morphological and optical properties of the nanorod heterojunctions were investigated. The results indicate that CdS single-crystalline domains with a mean diameter of about 7 nm are uniformly and conformally covered on the surface of the single-crystalline ZnO nanorods. ZnO absorption with a bandgap energy value of 3.30 ± 0.02 eV is present in all optical transmittance spectra. Another absorption edge close to 500 nm corresponding to CdS with bandgap energy values between 2.43 and 2.59 eV is observed. The dispersion in this value may originate in quantum confinement inside the nanocrystalline material. The appearance of both edges corresponds with the separation of ZnO and CdS phases and reveals the absorption increase due to CdS sensitizer. The photovoltaic performance of the resulting ZnO/CdS core/shell nanorod arrays has been investigated as solar cell photoanodes in a photoelectrochemical cell under white illumination. In comparison with bare ZnO nanorod arrays, a 13-fold enhancement in photoactivity was observed using the ZnO/CdS coaxial heterostructures. 相似文献
738.
YANG Jikuang XU Wei OTTE Dietmar 《机械工程学报(英文版)》2008,21(4):81-86
This paper aims at investigating brain injury mechanisms and predicting head injuries in real world accidents. For this purpose, a 3D human head finite element model (HBM-head) was developed based on head-brain anatomy. The HBM head model was validated with two experimental tests. Then the head finite element(FE) model and a multi-body system (MBS) model were used to carry out reconstructions of real world vehicle-pedestrian accidents and brain injuries. The MBS models were used for calculating the head impact conditions in vehicle impacts. The HBM-head model was used for calculating the injury related physical parameters, such as intracranial pressure, stress, and strain. The calculated intracranial pressure and strain distribution were correlated with the injury outcomes observed from accidents. It is shown that this model can predict the intracranial biomechanical response and calculate the injury related physical parameters. The head FE model has good biofidelity and will be a valuable tool for the study of injury mechanisms and the tolerance level of the brain. 相似文献
739.
The review focuses on the use on ultrasound in the synthesis of organofluorine compounds by direct introduction of fluorine atoms or fluorine containing moieties. After a short introduction about sonochemical effects reactions involving difluoromethyl, trifluoromethyl and higher perfluoroalkyl derivatives are described. Furthermore, the preparation of monofluorinated molecules from alkenes, alcohols, epoxides and aryl halides is reported. 相似文献
740.