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81.
Two new series of furochromone and benzofuran derivatives were designed, synthesized and evaluated for their in vitro anticancer activity against MCF-7 and MDA231 breast cancer cell lines. Compounds 5, 6, 7, 9, 15a, 16, 17a and 18 exhibited the best antiproliferative activities with IC50 values ranging from 1.19 to 2.78?µM against MCF-7 superior to lapatinib as reference standard (IC50; 4.69?µM). Compounds 15a and 18 revealed significant cytotoxic activity against MCF-7 and MDA231, therefore their inhibitory potencies against p38α MAP kinase were evaluated. Remarkably they exhibited significant IC50 of 0.04?µM comparable to SB203580 (IC50; 0.50?µM) as a reference standard. These promising results of cytotoxic activity and significant inhibition of p38α MAP kinase, were confirmed by exploring the effect of benzofuran derivative (18) on the apoptotic induction and cell cycle progression of MCF-7 cell line. Compound 18 induced preG1 apoptosis and cell growth arrest at G2/M phase preventing the mitotic cycle. Moreover it activated the caspase-7 which executes apoptosis. Molecular docking study was carried out using GOLD program to predict the mode of binding interaction of the synthesized compounds into the target p38α MAPK. Additionally, the physicochemical properties and ADME parameters of compound 18 were examined in silico to investigate its drug-likeness.  相似文献   
82.
Hexokinase‐2 is overexpressed in several carcinomas including breast cancer to sustain energy for rapidly dividing cells and associates with chemoresistance. However, the impact of chemo drugs (alone or in combination) on hexokinase activity and autophagic cell death is unclear. In this report, we used an in vivo murine adenocarcinoma model to validate the effects of As2O3 and cisplatin on hexokinase activity and autophagic cancer cell death. We found that the two drugs inhibit hexokinase activity and induce autophagic marker, beclin 1 expression. Interestingly, combining As2O3 with cisplatin synergistically enhanced these effects and alleviated oxidative stress often encountered in As2O3 treatment. Altogether, our data provide direct evidence that inhibition of hexokinase activity and induction of autophagic cell death are mediating the antineoplastic effects of As2O3 and cisplatin. Our findings raise the potential of combining As2O3 with cisplatin as an approach to augment cisplatin‐induced cell death and combat cisplatin chemoresistance in cancer.  相似文献   
83.
Cyclooxygenase-2 (COX-2) and transforming growth factor-beta1 (TGF-beta1) were modulated in a variety of viral infections, but there is a paucity of data about their role in the pathologic process of cirrhosis and/or hepatocellular carcinoma (HCC) following chronic hepatitis C virus (HCV) infection. The material of the current study included 50 cases of chronic hepatitis C (CHC) without cirrhosis, 30 cases of CHC with cirrhosis, and 30 cases of HCC with HCV admitted to the Gastroenterology and Hepatology Department of Theodor Bilharz Research Institute, Giza, Egypt. Fifteen wedge liver biopsies, taken during laparoscopic cholecystectomy, were included in the study as normal controls. Laboratory investigations, serologic markers for viral hepatitis, and serum alpha fetoprotein levels (alpha-FP) were done for all cases of the study. Immunohistochemistry using primary antibodies against both factors revealed weak to faint immunoreactivity to COX-2 and TGF-beta1 in normal hepatic tissue (< 30% and < 50% of the cells, respectively). COX-2 expression was upregulated in patients with CHC with and without cirrhosis, yet 80% of positively stained cirrhotic cases showed marked staining intensity. Higher COX-2 expression was observed in well-differentiated HCC cases (80%) with marked staining intensity (75%) compared with advanced HCC tumors (P < .001). TGF-beta1 was expressed in the hepatocytes of all cases of CHC with and without cirrhosis as well as in 67% of HCC cases. Extensive cytoplasmic expression was detected in 52%, 93.3%, and 46.6% of CHC patients without cirrhosis, patients with cirrhosis, and patients with HCC, respectively. A positive correlation was observed between hepatic expression of COX-2 and TGF-beta1 (r = 0.67, P < .05); however, no correlation was detected between the latter and grade of HCC differentiation (r = 0.33, P > .05). CONCLUSION: These findings may suggest that TGF-beta1 plays a role in hepatic cell damage following HCV infection thus stressing the usefulness of this cytokine as a prognostic marker for liver cell injury. However, COX-2 is a predictive marker for malignant transformation and has a role in the early stages of hepatocarcinogenesis, but not in the advanced stages. The combined expression of both factors in HCV-related HCC suggests their synergistic action in the pathophysiology of hepatocarcinogenesis.  相似文献   
84.
In this article, we report on the alkaloid profile and dynamic of alkaloid content and diversity in two Narcissus plants at different stages of development. The alkaloid profile of the two Narcissus species was investigated by GC/MS and HPTLC. Fifty eight Amaryllidaceae alkaloids were detected, and 25 of them were identified in the different organs of N. tazetta and N. papyraceus. The alkaloid 3‐O‐methyl‐9‐O‐demethylmaritidine is tentatively identified here for the first time from the Amaryllidaceae family, and four alkaloids (tazettamide, sternbergine, 1‐O‐acetyllycorine, 2,11‐didehydro‐2‐dehydroxylycorine) are tentatively identified for the first time in the genus Narcissus. The different organs of the two species analyzed showed remarkable differences in their alkaloid pattern, type of biosynthesis, main alkaloid and number of alkaloids. Lycorine‐type alkaloids dominated the alkaloid, metabolism in N. papyraceus, while alkaloids of narciclasine‐, galanthamine‐ and homolycorine‐types were found only in the species N. tazetta L.  相似文献   
85.
86.
The development of different approaches to use agricultural residues as a source of high value-added products, become a must, especially after the problems emerged due to their accumulation. This contribution demonstrates the potential of agricultural residues, Linuim usitatissium (flax seed) and Nigella sativa (black seed) peels, as raw materials for the production of bioactive products, botanical insecticides, against Cx. pipiens, with deep analysis to their chemical constituents by gas chromatography-mass spectrometry, the larvicidal efficacies of the three crude extracts (methylene chloride, petroleum ether and methanol 70%) from the two plant waste peels were evaluated for the first time against the late third instar larvae of Cx. pipiens. Results indicated different lethal doses in larvae depending on the efficacy of organic solvent used. For both compounds methanol 70% extracts produced the highest dry yield. The most efficient solvent is petroleum ether in case of both flax and Black seed peels. Petroleum ether extract exhibited the highest toxicity against Cx. pipiens with an LC50 of 69.6383 ppm. The same results for black seed indicated that petroleum ether was the most efficient against Cx. pipiens with an LC50 of 40.7748 ppm. The study revealed for the first time the type of phytochemical constituents presents in peels of flax and black seeds using GC–MS analysis which revealed twenty-eight constituents among extracts of flax and black seed peels ranging from to 58.8711% to 99.99% of the total extracts. GC–MS profiling showed that a five constituents, 9-2-Methyl-Z, Z-3, 13 octadecadienol (terpenoid), 9,17-Octadecadienal, (Z)-, Nonanoic acid, 9-oxo-, methyl ester, 9,12-Octadecadienoic acid Z,Z and Octasiloxane, 1,1,3,3,5,5,7,7,9,9,11,11,13,13,15,15-hexadecamethyl- have insecticidal activity beside many other biological activities as recorded from a variety of botanical extracts. While the constituents like Hexadecanoic acid, methyl ester and cis-9-Hexadecenal, both of them are larvicidal, cis-Vaccenic acid and 9-Oxononanoic acid showing only an insecticidal activity beside Undecanoic acid the mosquito repellent. The other six constituents Linoelaidic acid, Oleic Acid, Z-2-Octadecen-1-ol, 1-Methoxy-3-hydroxymethylheptane, Cis-11,14–Eicosadieonic acid-methyl ester and Heptasiloxane, 1,1,3,3,5,5,7,7,9,9,11,11,13,13-tetradecamethyl- are constituents of other plant extracts which showed as a whole an insecticidal activity.  相似文献   
87.
Heparin, a heterogeneous anionic polysaccharide, is the glycosaminoglycan (GAG) used clinically an anticoagulant. This anticoagulant activity is primarily derived from its binding to the serine protease inhibitor antithrombin III, a potent inhibitor of thrombin (factor IIa) and factor Xa. Heparin is a complex natural product and its in vitro synthesis is not yet possible due to the difficulty of organizing the many biosynthetic enzymes required for its synthesis. The principle natural sources for heparin include porcine intestine and bovine lung. These two sources pose concerns for religious and health reasons, respectively. To circumvent these concerns, GAG from the intestinal tissue of one humped camel was isolated. Chemical characterization of this newly isolated GAG and spectroscopic analysis by 1D and 2D 1H-NMR were undertaken. Unsaturated disaccharide compositional analysis was performed on the enzymatically depolymerized GAG and the molecular weight of the isolated GAG was determined by gradient polyacrylamide gel electrophoresis. Anticoagulant activity of the newly isolated GAG was tested by using an anti-factor Xa assay. The results of these studies suggest that the GAG from one humped camel intestine is a mixture of heparin and heparan sulfate and represents an alternative source of heparin.  相似文献   
88.
An integrated approach is used to develop a rapid sampling strategy for the quantitative analysis of in vivo kinetic behavior based on measured concentrations of intracellular metabolites in Saccharomyces cerevisiae. Emphasis is laid on small sample sizes during sampling and analysis. Subsecond residence times are accomplished by minimizing the dead volume of the sterile sampling system and by maximizing flow rates through application of vacuum to the sampling tubes in addition to the overpressure in the fermenter. A specially designed sample tube adapter facilitates sampling intervals of 4 to 5 s for various test tube types. Statistical analysis of the results obtained from enzymatic and liquid chromatography mass spectrometry (LC-MSMS) analysis of the metabolite concentrations was used to optimize the sampling protocol. The most notable improvement is reached through the introduction of vacuum drying of the cell extract. The presented system is capable of reliably dealing with fermenter samples as small as 1-g with a variation of less than 3%, and is thus ideally suited for intracellular measurements on small, lab-scale fermenters.  相似文献   
89.
90.
The present study investigates the chemical composition, antioxidant and antimicrobial bioactivities of essential oil and hexane extract from Citrus limon leaves. The isolation of essential oil was carried out using the Clevenger apparatus. The percentage yield of essential oil and hexane extract from Citrus limon leaves was 0.59 and 0.50 %, respectively. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging assay highlighted that Citrus limon leaves essential oil (CLEO) and hexane extract exhibited the significant antioxidant potential of 69.64 and 67.55 %, respectively, compared to the BHT standard. Similarly, a significant inhibition in linoleic acid peroxidation was recorded in both CLEO (81.93 %) and hexane extract (50.34 %). Characterization of chemical constituents in CLEO and extract was executed using GC/MS, where Limonene was detected as a major compound in CLEO (60.52 %) and hexane extract (73.62 %). The haemolytic activity ranged from 2.46 to 5.75 % revealing negligible cytotoxicity of CLEO and hexane extract. In silico studies agree with the in vitro antimicrobial studies, where vinimalol, taraxasterol, and moretenol present in CLEO showed strong interactions/inhibition against dihydroorotase and DNA gyrase from E. coli, and the tyrosyl-tRNA synthetase and DNA gyrase from S. aureus. Based on the current data, it may be concluded that both CLEO and hexane extract possessed significant bioactivities, such as antimicrobial and antioxidant activity, with minimal cytotoxicity.  相似文献   
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