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11.
Xu  Jing  Zhang  Zheng  He  Xiao-Mei  Wang  Ren-Qi  Hussain  Dilshad  Feng  Yu-Qi 《Mikrochimica acta》2018,185(1):1-9
Microchimica Acta - Porous graphitic carbon nitride (g-C3N4) was prepared by a one-step acid etching and ultrasonication process. It is found that the strong blue fluorescence of g-C3N4 (with...  相似文献   
12.
Flavonoids are famous for their antioxidant capacity and redox potential. They can combat with cell aging, lipid peroxidation, and cancer. In the present study, Artemisia annua hybrid (Hyb8001r) was subjected to qualitative and quantitative analysis of flavonoids through HPLC. Rol genes transgenics of A. annua were also evaluated for an increase in their flavonoid content along with an increase in antioxidant and cytotoxic potential. This was also correlated with the expression level of flavonoids biosynthetic pathway genes as determined by real-time qPCR. Phenylalanine ammonia-lyase and chalcone synthase genes were found to be significantly more highly expressed in rol B (four to sixfold) and rol C transgenics (3.8–5.5-fold) than the wild-type plant. Flavonoids detected in the wild-type A. annua through HPLC include rutin (0.31 mg/g DW), quercetin (0.01 mg/g DW), isoquercetin (0.107 mg/g DW) and caffeic acid (0.03 mg/g DW). Transgenics of the rol B gene showed up to threefold increase in rutin and caffeic acid, sixfold increase in isoquercetin, and fourfold increase in quercetin. Whereas, in the case of transgenics of rol C gene, threefold increase in rutin and quercetin, 5 fold increase in isoquercetin, and 2.6-fold increase in caffeic acid was followed. Total phenolics and flavonoids content was also found to be increased in rol B (1.5-fold) and rol C (1.4-fold) transgenics as compared to the wild-type plant along with increased free radical scavenging activity. Similarly, the cytotoxic potential of rol gene transgenics against MCF7, HeLA, and HePG2 cancer cell lines was found to be significantly enhanced than the wild-type plant of A. annua. Current findings support the fact that rol genes can alter the secondary metabolism and phytochemical level of the plant. They increased the flavonoids content of A. annua by altering the expression level of flavonoids biosynthetic pathway genes. Increased flavonoid content also enhanced the antioxidant and cytotoxic potential of the plant.  相似文献   
13.
The purpose of this study was to find the biological propensities of the vegetable plant Pleurospermum candollei by investigating its phytochemical profile and biological activities. Phytochemical analysis was done by spectroscopic methods to investigate the amount of total polyphenols, and biological evaluation was done by the different antioxidant, enzyme inhibitory (tyrosinase, α-amylase, and α-glucosidase), thrombolytic, and antibacterial activities. The highest amount of total phenolic and flavonoid contents was observed in methanolic extract (240.69 ± 2.94 mg GAE/g and 167.59 ± 3.47 mg QE/g); the fractions showed comparatively less quantity (57.02 ± 1.31 to 144.02 ± 2.11 mg GAE/g, and 48.21 ± 0.75 to 96.58 ± 2.30 mg QE/g). The effect of these bioactive contents was also related to biological activities. GCMS analysis led to the identification of bioactive compounds with different biological effects from methanolic extract (antioxidant; 55.07%, antimicrobial; 56.41%), while the identified compounds from the n-hexane fraction with antioxidant properties constituted 67.86%, and those with antimicrobial effects constituted 82.95%; however, the synergetic effect of polyphenols may also have contributed to the highest value of biological activities of methanolic extract. Molecular docking was also performed to understand the relationship of identified secondary metabolites with enzyme-inhibitory activities. The thrombolytic activity was also significant (40.18 ± 1.80 to 57.15 ± 1.10 % clot lysis) in comparison with streptokinase (78.5 ± 1.53 to 82.34 ± 1.25% clot lysis). Methanolic extract also showed good activity against Gram-positive strains of bacteria, and the highest activity was observed against Bacillus subtilis. The findings of this study will improve our knowledge of phytochemistry, and biological activities of P. candollei, which seems to be a ray of hope to design formulations of natural products for the improvement of health and prevention of chronic diseases; however, further research may address the development of novel drugs for use in pharmaceuticals.  相似文献   
14.
Journal of Solid State Electrochemistry - In the recent work, the scheelite-type ABO4 compound (A = Nd and B = Os) is synthesized via a hydrothermal route directly...  相似文献   
15.
Successful hydrothermal synthesis of pure ZSM-22 devoid of impurities is achieved under mild conditions of 433 K and horizontal stirring at 20 revolutions per minute (rpm) using Teflon-coated bar magnets to enhance gel mixing.  相似文献   
16.
In this research, bimetallic supported CNT modified electrode ( Fe,Ni/CNTs/GCE) has been developed for sensitive, stable and highly elctroactive sensing of glucose, ascorbic acid and hydrogen peroxide. Transition metals such as Iron (Fe) and Nickel (Ni) offer high electrical and thermal conductance, high active surface‐to‐volume ratio and presence of d‐band electrons gives enhanced electrocatalytic behavior. While, CNTs provide high surface area, stability and excellent conductivity. Synthesized material is characterized by SEM, EDS, XRD and FTIR to access morphology, elemental composition and structure. This unique combination is employed for the electrochemical sensing of ascorbic acid, glucose and hydrogen peroxide and different experimental parameters are optimized. Fe,Ni/CNTs/GCE shows good sensing efficiency at pH 7.4 which is ideally suitable for variety of analytes. The modified electrode also show good reproducibility and sensitivity under optimized conditions and can be reused upto 30 cycles without compromising the efficiency. With good linearity, reproducibility and limit of detection, this material possess significant potential as non‐enzymatic biosensor for variety of analytes.  相似文献   
17.
A comparative study of chiral separation of pantoprazole and rabeprazole is carried out using supercritical fluid chromatography and high-performance liquid chromatography. The columns used were Chiralpak IA and Chiralpak IE. The best mobile phase in supercritical fluid chromatography was carbon dioxide-0.2% triethylamine in methanol (60:40) and 0.1% triethylamine in n-hexane-ethanol (50:50) in high-performance liquid chromatography. For supercritical fluid chromatography, values of the retention factor of pantoprazole enantiomers were 3.97 and 4.88. These values for rabeprazole enantiomers were 6.10 and 7.52. The values of separation and resolution factor for pantoprazole and rabeprazole were 1.23 and 1.23 and 2.20 and 3.36, respectively. Similarly, for high-performance liquid chromatography, the values of retention factor for enantiomers of pantoprazole were 4.02 and 7.32. These values for rabeprazole enantiomers were 5.32 and 7.88, respectively. The values of separation and resolution factor for pantoprazole and rabeprazole were 1.82 and 1.48 and 9.22 and 6.58, respectively. A comparison was carried out, which confirmed supercritical fluid chromatography as the best method due to its fastness, eco-friendly, and inexpensiveness. The reported methods are effective, efficient, and reproducible and may be used to separate and identify pantoprazole and rabeprazole in any unknown samples.  相似文献   
18.
Enrichment of glycoproteins has been important because of their dynamicity and role in biological systems. Study of glycoproteins is complex because of the simultaneous glycosylation and deglycosylation inside the body. Often employed affinities for glycopeptides are hydrazide, boronic acid, or physiosorbed lectin on support materials. Cellulose, a natural polysaccharide, has rich surface chemistry, stable structure, low cost and availability in different variants. In present study, fibrous cellulose is oxidized using periodate to modify with boronic acid. Attachment of boronic acid is confirmed by Fourier transform infrared spectroscopy. Particle size and morphology of boronic acid@fibrous cellulose is studied by scanning electron microscopy. The enrichment efficiency is evaluated by using horseradish peroxidase as model protein. Boronic acid@fibrous cellulose is selective up to 1:250 for spiked horseradish peroxidase in bovine serum albumin digest, sensitive down to 0.1 femtomol and recovering 88.15% glycopeptides. Moreover, protein binding capacity is determined as 213 mg/g and 41% sequence coverage of horseradish peroxidase protein with all eight glycosylation sites detected. Total of 18 glycopeptides are enriched from immunoglobulin digest showing ability of boronic acid@fibrous cellulose to enrich glycoproteins from multiglycoforms. Enrichment from human serum recovers 18% extracellular and 72% secreted glycoproteins via bottom‐up approach and online tools.  相似文献   
19.
Three new compounds, the degraded ring Cseco‐tetranortriterpenoid nimbolicidin ( 1 ), the degraded hexanortriterpenoid nimbocin ( 2 ), and the seco‐norabietane diterpene nimbocinin ( 3 ), were isolated from the root bark of Azadirachta indica A.Juss . Compound 1 is O‐bearing both at C(28) and C(29), which has been hitherto unreported in tetranortriterpenoids; 2 represents the first hexanortriterpenoid with a truncated apotirucallane (or apoeuphane) skeleton; 3 is an unprecedented seco‐norabietane. Spectroscopic data and chemical transformations of these compounds provided their complete structures.  相似文献   
20.
The extraction of berberine was carried out from Berberis vulgaris, Berberis aquifolium, and Hydrastis canadensis plants using ethanol and water (70:30, v/v). The extracted berberine was characterized by ultraviolet-visible and Fourier-transform infrared spectroscopy. The purity of berberine was ascertained by thin-layer chromatography using n-propanol-formic acid-water (95:1:4) and (90:1:9) solvents. hRf values were in the range of 44–49 with compact spots (diameter 0.2–0.4 cm). HPLC was carried out using ammonium acetate buffer and acetonitrile in gradient mode with Zodiac (4.6 × 150 mm, 3 μm) column. The flow rate was 1.0 mL/min and detection was at 220 nm. The values of separation and resolution factors of the standard and the extracted berberine were in the range of 1.13–1.16 and 1.40–1.71, respectively. A comparison has shown that both thin-layer chromatography and high-performance liquid chromatography (HPLC) methods found applications in different situations and requirements. The extracted berberine samples were used to treat Leishmaniosis and the results showed better activity of berberine in comparison to the standard drug Amphotericin B. Briefly, the reported research is a novel and may be used to extract berberine from plants, separation and identification of berberine by thin layer chromatography and HPLC and to treat Leishmaniosis.  相似文献   
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