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91.
Arum dioscoridis and A. palaestinum (Araceae) are indigenous plant species in Jordan. HPLC-MS analysis of A. dioscoridis revealed the presence of apigenin, luteolin, quercetin, quercetin-3-O-β-glucoside, vitexin, isoorientin, esculin, and caffeic and ferulic acids. Both Arum spp., influenced gastrointestinal carbohydrate and lipid digestion and absorption. Orlistat inhibited dose dependently and highly substantially pancreatic lipase (PL) in vitro. Similar to orlistat, Arum species aqueous extracts (AEs), apigenin, caffeic acid and esculin exhibited a concentration related PL inhibition. Comparable to acarbose, dual inhibition of α-amylase/α-glucosidase was observed for both Arum species. Like guar gum, A. dioscoridis AE minimised substantially area under 24 h glucose curve. Acute starch-induced postprandial hyperglycaemia in overnight fasting rats was highly significantly (p?<?0.001) decreased by A. dioscoridis AE. A. palaestinum could not perform effectively in either starch- or glucose-fed fasting rats. No antiproliferative effects against colorectal cancer cell lines HT29, HCT116 and SW620 were detected for tested Arum spp.  相似文献   
92.
The paper is devoted to the investigation of a parabolic partial differential equation with non‐local and time‐dependent boundary conditions arising from ductal carcinoma in situ model. Approximation solution of the present problem is implemented by the Ritz–Galerkin method, which is a first attempt at tackling parabolic equation with such non‐classical boundary conditions. In the process of dealing with the difficulty caused by integral term in non‐local boundary condition, we use a trick of introducing the transition function G(x,t) to convert non‐local boundary to another non‐classical boundary, which can be handled with the Ritz–Galerkin method. Illustrative examples are included to demonstrate the validity and applicability of the technique in this paper. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
93.
Opuntia dillenii Ker Gawl. is one of the medicinal plants used for the prevention and treatment of diabetes mellitus (DM) in Morocco. This study aims to investigate the antihyperglycemic effect of Opuntia dillenii seed oil (ODSO), its mechanism of action, and any hypoglycemic risk and toxic effects. The antihyperglycemic effect was assessed using the OGTT test in normal and streptozotocin (STZ)-diabetic rats. The mechanisms of action were explored by studying the effect of ODSO on the intestinal absorption of d-glucose using the intestinal in situ single-pass perfusion technique. An Ussing chamber was used to explore the effects of ODSO on intestinal sodium-glucose cotransporter 1 (SGLT1). Additionally, ODSO’s effect on carbohydrate degrading enzymes, pancreatic α-amylase, and intestinal α-glucosidase was evaluated in vitro and in vivo using STZ-diabetic rats. The acute toxicity test on mice was performed, along with a single-dose hypoglycemic effect test. The results showed that ODSO significantly attenuated the postprandial hyperglycemia in normal and STZ-diabetic rats. Indeed, ODSO significantly decreased the intestinal d-glucose absorption in situ. The ex vivo test (Ussing chamber) showed that the ODSO significantly blocks the SGLT1 (IC50 = 60.24 µg/mL). Moreover, ODSO indu\ced a significant inhibition of intestinal α-glucosidase (IC50 = 278 ± 0.01 µg/mL) and pancreatic α-amylase (IC50 = 0.81 ± 0.09 mg/mL) in vitro. A significant decrease of postprandial hyperglycemia was observed in sucrose/starch-loaded normal and STZ-diabetic ODSO-treated rats. On the other hand, ODSO had no risk of hypoglycemia on the basal glucose levels in normal rats. Therefore, no toxic effect was observed in ODSO-treated mice up to 7 mL/kg. The results of this study suggest that ODSO could be suitable as an antidiabetic functional food.  相似文献   
94.
With a view to obtaining both enantiomers of 3-(4-methoxycarbonyl)phenyl-2-methyl-1-propanols, (R)-1 and (S)-1, from the respective racemate, (±)-1, the hydrolysis of its acetate, (±)-2, in the presence of porcine pancreatic lipase (PPL) has been studied. The optical puriry of (R)-1 and (S)-1 thus obtained was unsatisfactory (ee 22–27%), and could not be increased beyondee 33% by repeated enzymatic hydrolysis of the unconverted fraction of the acetate. In contrast with this, the biohydrogenation of 3-(4-methoxycarbonyl)phenyl-2-methyl-2-propen-1-ol (4) with fermentingSaccharomyces cerevisiae afforded (S)-1 of considerably higher optical purity (ee 41–90 %, depending on the strain). The stereochemical correlation of the products obtained in the two biochemical processes under study shows that the PPL-catalyzed hydrolysis of (±)-2 produces preferably (R)-1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 761–766, April, 1995.The authors express their gratitude to the Russian Foundation for Basic Research for financial support (Grant No. 93-03-5893).  相似文献   
95.
The chromium(III) complex, Cr(C7H3NO4)2·C4H12N5 (1), was synthesised by chelating chromium with dipicolinic (H2dipic) in methanol, and its structure was characterised using elemental analysis (EA), spectroscopy (infrared, UV–visible, and fluorescence) and single-crystal X-ray method. The density functional theoretical (DFT) computation was performed using the Gaussian 09 package. The stability of solution at different temperatures and pH values, the electrochemical, morphological and thermal properties of complex 1 were discussed. The preliminary bioactivities of complex 1 in streptozotocin (STZ)-induced type 2 diabetes mellitus (T2DM) mice were investigated using daily oral gavage for 12 weeks. The cytotoxicity was assessed using the methyl thiazolyl tetrazolium (MTT) assays, and the acute toxicity experiment test was carried out on healthy C57BL/6 mice with this complex. The complex 1 crystallised in the monoclinic system with the space group P2(1)/n, R1 = 0.0642. The DFT-optimised structure of complex 1 was in excellent agreement with the X-ray crystal structure. The complex 1 exhibited good physical and chemical properties and beneficial function on blood glucose and lipid metabolism for T2DM. The antidiabetic activity of chromium(III) might be associated with chromium(VI). Furthermore, the cytotoxicity and the acute toxicity experiments showed that the complex 1 was hypotonic and secure to organism. The study of complex 1 showed that the prepared complex on the basis of H2dipic and Met could inhibit hyperglycaemia and hyperlipidaemia in vivo and did not have potential toxicity. These results demonstrated that the complex 1 might provide an important reference for the development of functional hypoglycaemic foods or pharmaceuticals of T2DM.  相似文献   
96.
In recent years, scientists have tried to increase organic chemistry productions for the treatment of many cancers such as the lung cancers. In this regard, gold nanoparticles have a special place. Furthermore, one of the therapeutic properties of Verbascum chinense L. is increasing the physiological potentials of the body against several cancers. In the present study, gold nanoparticles were prepared and synthesized in aqueous medium using V. chinense leaf extract. We assessed the anti-human lung cancers potentials of these nanoparticles against well-differentiated bronchogenic adenocarcinoma, moderately differentiated adenocarcinoma of the lung, and poorly differentiated adenocarcinoma of the lung cell lines. AuNPs were characterized and analyzed by common nanotechnology techniques including FT-IR and UV–Vis. Spectroscopy, Field Emission-Scanning Electron Microscopy, and Transmission Electron Microscopy. In the FT-IR test, the presence of many antioxidant compounds with related bonds caused the excellent condition for reducing of gold in the gold nanoparticles. In UV–Vis, the clear peak in the wavelength of 542 nm indicated the formation of gold nanoparticles. We assessed the anti-human lung cancers potentials of these nanoparticles against well-differentiated bronchogenic adenocarcinoma, moderately differentiated adenocarcinoma of the lung, and poorly differentiated adenocarcinoma of the lung cell lines. AuNPs had excellent anti-human lung cancer effects dose-dependently against HLC-1, LC-2/ad, and PC-14 cell lines. The best result of anti-human lung cancer activities of AuNPs against above cell lines was observed in the case of the PC-14 cell line. In conclusion, the synthesized AuNPs showed significant anti-human lung cancer properties against well-differentiated bronchogenic adenocarcinoma, moderately differentiated adenocarcinoma of the lung, and poorly differentiated adenocarcinoma of the lung cell lines in a dose depended on manner. After confirming in the in vivo and clinical trials, AuNPs can be administrated in human for the treatment of humans’ lung cancers especially well-differentiated bronchogenic adenocarcinoma, moderately differentiated adenocarcinoma of the lung, and poorly differentiated adenocarcinoma of the lung.  相似文献   
97.
Pancreatic cancer is one of the most malignant cancers with high mortality. Therefore, it is of great urgency to develop new agents that could improve the prognosis of Pancreatic cancer patients. Chinese propolis (CP), a flavonoid-rich beehive product, has been reported to have an anticancer effect. In this study, we applied CP to the human Pancreatic cancer cell line Panc-1 to verify its impact on tumor development. CP induced apoptosis in Panc-1 cells from 12.5 µg/mL in a time- and dose-dependent manner with an IC50 value of approximately 50 µg/mL. Apoptosis rate induced by CP was examined by Annexing FITC/PI assay. We found that 48 h treatment with 50 µg/mL CP resulted in 34.25 ± 3.81% apoptotic cells, as compared to 9.13 ± 1.76% in the control group. We further discovered that the Panc-1 cells tended to be arrested at G2/M phase after CP treatment, which is considered to contribute to the anti-proliferation effect of CP. Furthermore, our results demonstrated that CP suppressed Panc-1 cell migration by regulating epithelial–mesenchymal transition (EMT). Interestingly, the Hippo pathway was activated in Panc-1 cells after CP treatment, serving as a mechanism for the anti-pancreatic cancer effect of CP. These findings provide a possibility of beehive products as an alternative treatment for pancreatic cancer.  相似文献   
98.
Libertellenone H (LH), a marine-derived pimarane diterpenoid isolated from arctic fungus Eutypella sp. D-1, has shown effective cytotoxicity on a range of cancer cells. The present study is to explore the anticancer effect of LH on human pancreatic cancer cells and to investigate the intracellular molecular target and underlying mechanism. As shown, LH exhibited anticancer activity in human pancreatic cancer cells by promoting cell apoptosis. Mechanistic studies suggested that LH-induced reactive oxygen species (ROS) accumulation was responsible for apoptosis as antioxidant N-acetylcysteine (NAC) and antioxidant enzyme superoxide dismutase (SOD) antagonized the inhibitory effect of LH. Zymologic testing demonstrated that LH inhibited Trx system but had little effect on the glutathione reductase and glutaredoxin. Mass spectrometry (MS) analysis revealed that the mechanism of action was based on the direct conjugation of LH to the Cys32/Cys35 residue of Trx1 and Sec498 of TrxR, leading to a decrease in the cellular level of glutathione (GSH) and activation of downstream ASK1/JNK signaling pathway. Taken together, our findings revealed LH was a marine derived inhibitor of Trx system and an anticancer candidate.  相似文献   
99.
Pancreatic fistula is a complication that frequently occurs after pancreatic surgery. Although various attempts have been made to prevent pancreatic fistula after pancreatic surgery, no effective methods have been developed thus far. In this study, to prevent the pancreatic fistula, we attempted to prepare the hydrogels consisting of two types of polyvinyl alcohol (PVAs), Poval® and Exceval® by the freezing–thawing (F/T) method. As the concentration and the number of F/T cycles increased, it was revealed that the swelling degree tended to decrease, and tensile strength tended to increase. Especially, Exceval® formed more robust hydrogels than that of Poval® hydrogel prepared by the same conditions. Furthermore, the release behavior of tartrazine from 10% Exceval® hydrogels differed depending on the number of F/T cycles. It was also revealed that the diffusion pattern of the drug in the hydrogel differed along with the release, and the entire amount of tartrazine in the hydrogel was released by 120 min. As nafamostat mesylate was loaded, in vivo study, Pancreatic enzyme values were obtained after 48 h, which allowed comparison of the preventive effects against pancreatic fistula between the untreated group, the Exceval® hydrogel group, and nafamostat mesylate-containing Exceval®-applied group. Furthermore, there was a significant difference between the untreated group and the hydrogel-applied group. Besides, PVA hydrogels prepared by the F/T method could probably absorb pancreatic enzymes. This study found that Exceval® hydrogel prepared by the F/T method was considered a novel hydrogel formulation to prevent pancreatic fistula.  相似文献   
100.
In current nanoscience bioengineered magnetic nanoparticles (NPs) have come into prominence with considerable impact. These advanced functional materials find outstanding applications in chemical science in catalysis, environmental issues, sensing etc, as well as in biology as drug delivery agent, chemical therapeutics and others. We have been prompted to architect and synthesize a novel Au NP adorned over chitosan-biguanidine polyplex modified core–shell type magnetic nanocomposite (Fe3O4/CS-biguanidine/Au NPs). The bioshells facilitate to protect the core ferrite NPs as well as provides stability to the synthesized Au NPs by capping. The material was characterized using different analytical techniques like Fourier Transformed Infra-Red spectroscopy (FT-IR), Inductively Coupled Plasma-Optical Emission Microscopy (ICP-OES), Field Emission Scanning Electron Microscopy (FE-SEM), Energy Dispersive X-ray spectroscopy (EDX), Transmission Electron Microscopy (TEM), Vibrating Sample Magnetometer (VSM) and X-ray Diffraction (XRD) studies. We explored the biological application of the nanocomposite in determining cytotoxicity of three adenocarcinoma cell lines (PC-14, LC-2/ad, HLC-1) through the MTT assay. The material showed very good activity by exhibiting very low % cell viability over the cell lines dose-dependently. The IC50 of Fe3O4/CS-biguanidine/Au NPs were observed 503, 398 and 475 µg/mL respectively against the three cell lines. The best output was observed at a concentration of 1000 µg/mL of catalyst in terms of cytotoxicity and inhibition of lung cancer growth. The anti-cancer potential was found in close relation to their antioxidant potential.  相似文献   
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