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Abstract

This study aimed to determine the heavy metals (HMs) contaminations in soil of the Hattar industrial estate (HIE), Haripur, Khyber Pakhtunkhwa. For this purpose, various types of soils were collected in HIE and analyzed for the HMs concentrations. The HMs showed highest contamination levels in wastewater irrigated agriculture soil (WWIAS), followed by waste dump site soil (WDSS), and the lowest in range land soil (RLS). Determined HMs concentrations were used for pollution quantification factors, including contamination factors (CFs), pollution load index (PLI), ecological risk factor (ER), and potential health risk assessment, including chronic or non-cancer and cancer risk levels.  相似文献   
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Metallic nanoparticles are attractive candidates as MRI contrast agents and mediators for drug delivery, diagnostics, and therapy. Direct contact and exposure to blood circulation is common in many such applications. The consequent thrombotic response may therefore be important to study. The main objective of the present work was to study how platelet functions were changed in the presence of different nano-surface or surface capping, which may provide a measure for the safety of a nanoparticle, and also assess the use of such nanoparticles in platelet modulation. Aggregometry, ATP release reaction, flow cytometry and immune-blotting studies were performed to study platelet response to different nano-particles (iron oxide, gold and silver). For each nanoparticle surface conjugation (capping) was varied. It was found that citric acid functionalized iron oxide nanoparticles have anti-platelet activity, with a decrease in aggregation, tyrosine phosphorylation level, and granule release. On the other hand in other cases (e.g. gold nanoparticles) pro-aggregatory response was observed in the presence of nanoparticles and, in some cases, the nanoparticles behaved neutrally (e.g. for starch-coated iron oxide nanoparticles). Therefore, nanoparticles can induce antiplatelet or a pro-aggregatory response, or remain neutral depending on surface capping. A related observation is that antiplatelet drugs can be made more potent by nanoparticle conjugation.  相似文献   
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Room temperature absorption spectra of thin, slices of rat tissue, freshly harvested, have been measured in the ultra-violet to near infra-red range and compared with light absorption in a blood sample. Absorption of various tissue materials showed two strong bands peaking at 430 and 1940 nm with two weak absorption bands at 550 and 1450 nm. Blood shows reduced absorption at all of these wavelengths, but the spectra are strikingly similar to those of solid tissue. Absorption spectra taken from kidney which had been irradiated at 430 nm from a nitrogen laser-pumped tunable dye laser showed a definite decrease in absorption with exposure time at 430 nm with an increase in absorption at 440 nm. This band, the Soret absorption band, is characteristic of deoxygenated haemoglobin. The observed decrease in absorption may be due to photochemical reactions involving these haemoglobin derivatives or due to thermo-mechanical shock effects.  相似文献   
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Studies of bioluminescence in living animals, such as cell-based biosensor applications, require measurement of light at different wavelengths, but accurate light measurement is impeded by absorption by tissues at wavelengths<600 nm. We present a novel approach to this problem--the use of a plastic window in the skin/body wall of mice--that permits measurements of light produced by bioluminescent cells transplanted into the kidney. The cells coexpressed firefly luciferase (FLuc), a vasopressin receptor--Renilla luciferase (RLuc) fusion protein, and a GFP2-beta-arrestin2 fusion protein. Following coadministration of two luciferase substrates, native coelenterazine and luciferin, bioluminescence is measured via the window using fiber optics and a photon counter. Light emission from the two different luciferases, FLuc and RLuc, is readily distinguishable using appropriate optical filters. When coelenterazine 400a is administered, bioluminescence resonance energy transfer (BRET) occurs between the RLuc and GFP2 fusion proteins and is detected by the use of suitable filters. Following intraperitoneal injection of vasopressin, there is a marked increase in BRET. When rapid and accurate measurement of light from internal organs is required, rather than spatial imaging of bioluminescence, the combination of skin/body wall window and fiber optic light measurement will be advantageous.  相似文献   
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A battery of bioassays was used to assess the ecotoxicological risk of soil spiked with a range of phenanthrene levels (0.95, 6.29, 38.5, 58.7, 122, and 303 μg g?1 dry soil) and aged for 69 days. Multiple species (viz. Brassica rapa, Eisenia feotida, Vibrio fischeri), representing different trophic levels, were used as bioindicator organisms. Among acute toxicity assays tested, the V. fischeri luminescence inhibition assay was the most sensitive indicator of phenanthrene biotoxicity. More than 15 % light inhibition was found at the lowest phenanthrene level (0.95 μg g?1). Furthermore, comet assay using E. fetida was applied to assess genotoxicity of phenanthrene. The strong correlation (r 2 ≥ 0.94) between phenanthrene concentration and DNA damage indicated that comet assay is appropriate for testing the genotoxic effects of phenanthrene-contaminated soil. In the light of these results, we conclude that the Microtox test and comet assay are robust and sensitive bioassays to be employed for the risk evaluation of polycyclic aromatic hydrocarbon-contaminated soil.  相似文献   
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Access to big data analyzed by supercomputers using advanced mathematical algorithms (i.e., deep machine learning) has allowed for enhancement of cognitive output (i.e., visual imaging interpretation) to previously unseen levels and promises to fundamentally change the practice of medicine. This field, known as “artificial intelligence” (AI), is making significant progress in areas such as automated clinical decision making, medical imaging analysis, and interventional procedures, and has the potential to dramatically influence the practice of interventional cardiology. The unique nature of interventional cardiology makes it an ideal target for the development of AI-based technologies designed to improve real-time clinical decision making, streamline workflow in the catheterization laboratory, and standardize catheter-based procedures through advanced robotics. This review provides an introduction to AI by highlighting its scope, potential applications, and limitations in interventional cardiology.  相似文献   
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