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571.
Sleep and Biological Rhythms - Restless legs syndrome is a neuromotor problem which is more common among pregnant women. Several studies have reported different prevalences for this disorder....  相似文献   
572.
Trachyspermum ammi (L.) Sprague (Ajowan) is an endangered medicinal plant with useful pharmaceutical properties. Ex situ conservation of this medicinal plant needs the development of an in vitro regeneration protocol using somatic embryogenesis. In the present study, a high-precision image-processing approach was successfully applied to measure physical properties of embryogenic callus. Explant age and the concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D), kinetin (Kin), and sucrose were used as inputs, and an artificial intelligence technique was applied to predict physical properties of embryogenic callus, and the number of somatic embryos produced. Artificial neural network (ANN) models were tested to find the best combinations of input variables that affected output variables. The lower values of root mean square error, and mean absolute error, and the highest values of determination coefficient, were achieved when all four input variables were applied to predict the number of somatic embryos, the area of the callus, the perimeter of the callus, the Feret diameter of the callus, the roundness of the callus, and the true density of the callus in ANN models. The highest measured and predicted number of somatic embryos were achieved from the interaction of 15-d-old explants?×?1.5 mg L?1 2,4-D?×?0.5 mg L?1 Kin?×?2.5% (w/v) sucrose. Based on sensitivity analysis, the 2,4-D concentration was the most important component in the culture medium that affected the number of somatic embryos and physical properties of the embryogenic callus tissue.  相似文献   
573.
Dendritic cells are special and powerful antigen‐presenting cells that can induce primary immune responses against tumour‐associated antigens. They can present antigens via both MHC‐I and MHC‐II, so they have the ability to stimulate both cytotoxic T lymphocytes and T helper cells. Furthermore, CD8+ cytotoxic T lymphocytes require activation by CD4+ T cells. This requires a CD4+T cell activator molecule, of which PADRE is one of the best. We chose an approach to use both of these important arms of the immune system. We prepared dendritic cells from mouse bone marrow, loaded them with our target peptides (P5 peptide alone or P5 + PADRE), and then injected these pulsed dendritic cells alone or in combination with CpG‐ODN (as adjuvant) into BALB/C mice. After the last boosting dose, mice were inoculated with TUBO cells, which overexpress HER2/neu. Two weeks after the tumour cell injection, immunological tests were performed on splenocyte suspensions, and the remaining mice were evaluated for tumour growth and survival. Our data indicate the formulation that contains PADRE plus P5 loaded onto DC in combination with CpG‐ODN was the most effective formulation at inducing immune responses. Interferon production in CD4+ and CD8+ gated cells, cytotoxicity rates of target cells and mice survival were all significantly greater in this group than in controls, and all the mice in this group were tumour‐free throughout the experiment. Based on our results and the role of HER2/neu as a candidate in human immunotherapy, this approach may be an effective cancer treatment.  相似文献   
574.
All current highest efficiency perovskite solar cells (PSCs) use highly toxic, halogenated solvents, such as chlorobenzene (CB) or toluene (TLN), in an antisolvent step or as solvent for the hole transporter material (HTM). A more environmentally friendly antisolvent is highly desirable for decreasing chronic health risk. Here, the efficacy of anisole (ANS), as a greener antisolvent for highest efficiency PSCs, is investigated. The fabrication inside and outside of the glovebox showing high power conversion efficiencies of 19.9% and 15.5%, respectively. Importantly, a fully nonhalogenated solvent system is demonstrated where ANS is used as both the antisolvent and the solvent for the HTM. With this, state‐of‐the‐art efficiencies close to 20.5%, the highest to date without using toxic CB or TLN, are reached. Through scanning electron microscopy, UV–vis, photoluminescence, and X‐ray diffraction, it is shown that ANS results in similar mixed‐ion perovskite films under glovebox atmosphere as CB and TLN. This underlines that ANS is indeed a viable green solvent system for PSCs and should urgently be adopted by labs and companies to avoid systematic health risks for researchers and employees.  相似文献   
575.
Compact TiO2 is widely used as an electron transport material in planar‐perovskite solar cells. However, TiO2‐based planar‐perovskite solar cells exhibit low efficiencies due to intrinsic problems such as the unsuitable conduction band energy and low electron extraction ability of TiO2. Herein, the planar TiO2 electron transport layer (ETL) of perovskite solar cells is modified with ionic salt CuI via a simple one‐step spin‐coating process. The p‐type nature of the CuI islands on the TiO2 surface leads to modification of the TiO2 band alignment, resulting in barrier‐free contacts and increased open‐circuit voltage. It is found that the polarity of the CuI‐modified TiO2 surface can pull electrons to the interface between the perovskite and the TiO2, which improves electron extraction and reduces nonradiative recombination. The CuI solution concentration is varied to control the electron extraction of the modified TiO2 ETL, and the optimized device shows a high efficiency of 19.0%. In addition, the optimized device shows negligible hysteresis, which is believed to be due to the removal of trap sites and effective electron extraction by CuI‐modified TiO2. These results demonstrate the hitherto unknown effect of p‐type ionic salts on electron transport material.  相似文献   
576.
Intrauterine infection is a major cause of immune imbalance at the maternal-fetal interface, which leads to spontaneous abortion, premature rupture of the fetal membranes, and preterm birth. Human amniotic epithelial cells (hAECs) play a fundamental role in the maintenance of pregnancy. We hypothesize that bacteria influence the immunomodulatory effects of hAECs through stimulation of Toll-like receptors (TLRs). Here, we investigated how lipopolysaccharide (LPS) as a bacterial component affects anti-inflammatory and pro-inflammatory cytokines production of hAECs. Human placentas were obtained from six healthy pregnant women and hAECs were isolated. The phenotypic characteristics of hAECs were determined by flow cytometry. The hAECs (4?×?105 cells/ml) were cultured in the presence or absence of LPS (5?μg/ml). The viability of the cells was assessed and culture supernatants of hAECs were collected after 24, 48 and 72?h of incubation. The levels of transforming growth factor-beta1 (TGF-β1), interleukin-4 (IL-4), tumor necrosis factor-alpha (TNF-α), interleukin-17?A (IL-17A), and interferon-gamma (IFN-γ) were measured by ELISA. Our data showed that LPS treatment did not affect the viability of hAECs, while had a stimulatory effect on TGF-β1 production of hAECs (p?<?0.001). A significant reduction in IL-4 production of LPS-stimulated hAECs was observed (p?<?0.05). LPS enhanced the production of TNF-α and IL-17?A of hAECs (p?<?0.05–0.0001). The IFN-γ level was only detectable in two culture supernatants of hAECs, and the level was unchanged after stimulation with LPS. Based on these findings, LPS may play a pivotal role in immune imbalance at the feto-maternal interface through affecting anti-inflammatory and pro-inflammatory cytokines production of hAECs.  相似文献   
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