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21.
Encapsulation with PLGA of I3C and radioiodination have been performed. Anticancerogenic effects of I3C and I3C-PLGA have been investigated utilizing in vitro methods on breast adenocarcinoma epithelial (MCF7), colon adenocarcinoma epithelial (Caco2), prostate carcinoma epithelial (PC3) cells. Characterization of I3C-PLGA have been performed with DLS method and SEM analysis. I3C and I3C-PLGA compounds have been radiolabeled in high yields with 131I which is widely used for diagnosis and treatment in Nuclear Medicine. All experimental results demonstrated that radioiodinated compounds are promising in order to be used in Nuclear Medicine as well as present study contributed previously reported studies.  相似文献   
22.
The purpose of this study was to determine the relationship between the problems teachers preferred in mathematics lessons and student achievement in different types of problems. In accordance with this purpose, nine mathematics teachers were interviewed, and corresponding problems were prepared and administered to 225 eighth-grade students. The findings indicate that problem types are dependent on teacher preferences. It was found that curriculum-dependent and routine problems were dominant for teacher preferences. Students are more successful at with missing data, problems that are visual and do not require the use of different strategies. They have lower success at long problems, those that contain irrelevant data, problems that require the use of different strategies and difficult problem types. It was found that problem types at which students were successful and which teachers preferred were related. These results relay information about problems used in the learning environment and effect of problem-solving experiences on students' success.  相似文献   
23.
In current study, ethyl-morphine (em) was synthesized from the morphine and glucuronidated via enzymatic mechanism. The conjugated glucuronide ethyl-morphine (em-glu) was radiolabeled with 131I using iodogen method. The quality control studies of radiolabeled compound (131I-em-glu) were done with Thin Layer Radio Chromatography to confirm the radiolabeling efficiency. Biodistribution studies of 131I labeled em-glu were run on healthy male Albino Wistar rats. The distribution figures demonstrated that 131I-em-glu was eliminated through the small intestine, large intestine and accumulated in urinary bladder both receptor blocked and unblocked biodistribution studies. A greater uptake of the radiolabeled substance was observed in the m.pons, hypothalamus and mid brain than in the other branches of the rats’ brains.  相似文献   
24.
Poly(vinyl alcohol)‐pyrene‐anti‐metadherin (PVA‐Py‐(Anti‐MTDH)), a novel antibody based water soluble probe containing both fluorescent and target sites in the structure for in vitro imaging of breast cancer cells is reported here. Since breast cancer cells have an excess of MDTH protein expressed on the surface, a PVA‐Py prepared by “Click chemistry” approach is targeted by Anti‐MTDH antibody and applied to the MCF‐7 cell line. After characterization, the designed architecture was evaluated in terms of cell incorporation efficiency and compared with a non‐targeted structure (PVA‐Py). Atomic force microscopy (AFM) and fluorescence microscopy images of cells after incubation of the probe molecules were also obtained to monitor the interaction of the probes with the cancerous cells.

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25.
The degradation of crystal violet in aqueous solution was investigated using kaolin-supported zero-valent iron nanoparticles (K-nZVI). It was found that K-nZVI with a ratio of kaolin:zero-valent iron nanoparticles (nZVI) at 1:1 was most effective in removing crystal violet. Batch experiments show that more than 97.29?% crystal violet was degraded using K-nZVI, while only 24.36?% was removed using nZVI after reacting for 7?min, where the solution contained 100?mg?L?1 crystal violet at pH 6.5. This is due to a decrease in aggregation of Fe0 nanoparticles and enhanced their reactivity in the presence of kaolin, which was confirmed by the characterization using scanning electron microscopy. X-ray diffraction shows the formation of iron oxide and hydroxide, while UV?CVis spectral shows that the absorption peak of crystal violet was reduced, as well as Fourier transform infrared shows that new bands were formed after K-nZVI reacting with crystal violet. These suggest that degradation of crystal violet by K-nZVI include the oxidation of iron, the adsorption of crystal violet onto the K-nZVI, the transformation of crystal violet to leuko-crystal violet, and finally the cleavage of C=C bond.  相似文献   
26.
Diethylstilbestrol (DES) is a synthetic non-steroidal estrogen, pharmacologic effects of which resemble natural estrons; today it is being used to treat some types of postmenopausal breast cancer and advanced prostate cancer. The aim of current study is conjugation of glucuronic acid (G) to DES and to evaluate radiopharmaceutical potential of this estrogen glucuronide derivative (DESG) which is specific to β glucuronidase enzyme consisting tumor cells. Taking into consideration the compatibility to the chemical structures of the synthesized product, 131I and 125I were chosen as the appropriate radionuclides and DESG was labeled with these radionuclides utilizing iodogen method. The radiochemical yields of 125/131I-DESG were over 90 % according to thin layer radio chromatography method. The biodistribution of 131I-DESG in healthy female Wistar Albino rats has been investigated and the range of the breast/blood and breast/muscle ratios were approximately 2 and 13 in 240 min for ER unsaturated studies. Effects of the radioiodinated DES and DESG on the cells were examined using MCF-7, A-549, Caco-2 cell lines. 125I-DESG has higher incorporation percentages than 125I-DES on MCF-7 cells. The radioiodinated DESG has the desired radiopharmaceutical properties which could be candidate radiopharmaceuticals for diagnosis and especially radionuclide therapy of breast tumors.  相似文献   
27.
Summary An estrogen derivative, β-estradiol or 1,3,5,(10)-estratriene-3,17β-diol) attached to diethylenetriamine pentaacetic acid (DTPA) was synthesized in six experimental steps. At the end of these steps, a DTPA-attached estradiol derivative called deoxy-demethyl homoestradiolyl-diethylenetriamine-pentaacetic acid (ESTDTPA) was obtained. The synthesized compounds were labeled with 99mTc. Thin layer radio chromatography (TLRC) was used to determine radiochemical yields and stabilities.Structural investigations confirmed the structures. The labeling yield was satisfactory (about 95%), and 99mTc-ESTDPTA was stable in neutral medium at room temperature for 5 hours. Biodistribution studies were performed on normal and DMBA-induced, tumor bearing female Albino Wistar rats. The activity per gram tissue was calculated, and time-activity curves were plotted. ESTDTPA uptake by uterus reached a level of 20.73% dose/g, showing a maximum within 5 minutes after injection. Ovary and breast showed similar biodistribution profiles. The kidneys, which are the primary organs of metabolism and excretion of estrogen, showed a high 99mTc-ESTDTPA uptake. The imaging studies were performed on normal and tumor bearing female Albino Wistar rats using a Camstar XR/T gamma-camera. Gamma-scintigraphy studies showed that tumors could be well visualized in a few minutes and clearly differentiated from other organs, such as bladder and liver by 24 hours.  相似文献   
28.
Helicobacter pylori (H. pylori) is a global health threat, and the World Health Organization has included H. pylori among 12 bacterial species that require high priority future strategies for the development of new antibiotics due mainly to its high rates of resistance. Metallic nanoparticles are known for their antimicrobial properties. The FDA (Food and Drug Administration) has approved zinc oxide nanoparticles (ZnONPs) as biocompatible antimicrobials. Green synthesis of ZnONPs was performed based on Oak galls extract (OGE) and was characterized by UV, IR, DLS, TEM, and SEM measurements. In addition, LC-MS/MS was used for the identification of OGE constituents. A checkerboard assay was used to evaluate the activity of synthesized Qi-ZnONPs and OGE against H. pylori, and their synergistic effects with amoxicillin were evaluated. LC-MS/MS analyses identified 20 compounds as major gallic acid conjugates. The ZnONPs had average particle sizes of 5.5 nm (DLS) and 7.99 nm (TEM). Both OGE and Qi-ZnONPs exhibited moderate activity against H. pylori. Amoxicillin and Qi-ZnONPs combinations (1:2 and 1:4 amoxicillin:/Qi-ZnONPs) significantly decreased the MIC90 by two-fold and four-fold, respectively, and FIC values for the combinations were more significant than with OGE alone. OGE is rich in phenolics. The synergism between Qi-ZnONPs and amoxicillin can provide an alternative safe agent of low cost to combat H. Pylori infections.  相似文献   
29.
Modification of the magnetic properties of a drug can be used to direct the drug to the desired site, enhancing its therapeutic effectiveness and reducing side effects. In this study, surface-modified magnetic nanoparticles were immobilized with uracil glucuronide derivatives and then labeled with I-125. The morphology, structure, and composition of the magnetic particles were examined by TEM, SEM, VSM, and XRD. The particles sizes were about 50 nm. The labeling yield was 93.8% for uracil-O-glucuronide-immobilized magnetic particles and 95.0% for uracil-N-glucuronide-immobilized magnetic particles. The cell incorporation rates of N- and O-glucuronides were higher than those of uracil. The incorporation rates of uracil-, O-glucuronide-, and N-glucuronide-conjugated magnetic particles were all high. The cell incorporation rates of ligand-conjugated magnetic particles increased under a magnetic field.  相似文献   
30.
Codeine which was extracted from dry capsules of the opium poppy (Papaver somniferum) was purified by HPLC (High Performance Liquid Chromatography) and characterized by NMR (Nuclear Magnetic Resonance) and IR (Infrared) spectroscopy techniques. The purified compound was labeled with 131I and biodistribution studies were performed in rats. Radioiodinated codeine distributed uniformly in the cerebellum, m.pons, striatum and hypothalamus while the other branch of brain and Stomach, urinary bladder, and small intestine uptakes were significantly higher than other tissues.  相似文献   
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