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881.
Here we present the synthesis of the new Ni(II) complexes with chelating ligands 1-benzothiazol-2-yl-3,5-dimethyl-1H-pyrazole (a), 5-(2-hydroxyphenyl)-3-methyl-1-(2-pyridylo)-1H-pyrazole-4-carboxylic acid methyl ester (b) and 1-benzothiazol-2-yl-5-(2-hydroxyphenyl)-3-methyl-1H-pyrazole-4-carboxylic acid methyl ester (c). These ligands ac create solid complexes with Ni(II). The crystal and molecular structures of two complexes were determined by X-ray diffraction method. Thermal stability of two complexes with ligand c by TG/DTG and DSC methods were also shown. Cytotoxic activity of all the complexes against three tumour cell lines and to normal endothelial cells (HUVEC) was also estimated. Complexes with ligand c exhibited relatively high cytotoxic activity towards HL-60 and NALM-6 leukaemia cells and WM-115 melanoma cells. Cytotoxic effectiveness of one of these complexes against melanoma WM-115 cells was two times higher than that of cisplatin. The protonation constant log K = 9.63 of ligand b corresponding to the phenol 2-hydroxy group has been determined in 10% (v/v) DMSO/water solution (25 °C). The coordination modes (formation of two monomeric species: NiL and NiL2) in the complexes with Ni(II) are discussed for b on the basis of the potentiometric and UV/Vis data.  相似文献   
882.
Insulin significantly influences Ca(2+) signals evoked by various stimulants. In type 1 recent onset diabetes mellitus the proliferative response of T cells is significantly decreased. The number of clinical trials exploring the role of anti-CD3 monoclonal antibodies (mAb) as a therapeutic agent in recent onset diabetes mellitus type 1 is increasing last years. Therefore, a better understanding of the interplay between T cell receptor (TCR) dependent Ca(2+) increase, and insulin is of vital clinical significance. The aim of the study was to assess the effect of insulin on TCR evoked Ca(2+) responses in T lymphocytes obtained from healthy volunteers and patients suffering from long lasting diabetes mellitus type 1. Analysis was performed with use of the flow cytometer. We demonstrated that T cells ability to mobilize Ca(2+) was significantly reduced in long lasting diabetes mellitus type 1. Ca(2+) decrease achieved by the long term incubation with anti-CD3 mAb in T cells from healthy volunteers was restored by insulin. Strong interrelationship between baseline Ca(2+) level and plateau phase response to TCR stimulation was observed in the cytoplasm of cells pre-incubated with insulin from both healthy subjects and diabetic patients (r = 0.95, p < 0.0001 and r = 0.94, p < 0.0001, respectively). We postulate the existence of the interplay between TCR mediated activation and insulin. The TCR-insulin interplay is blunted in long lasting diabetes mellitus type 1. These observations may have an important implication for future therapeutic options in diabetes.  相似文献   
883.
BackgroundAlendronate can induce esophagitis and stomach ulceration requiring the concurrent use of drugs which decrease HCl production. The aim of the present study was to investigate the effect of concurrent administration of proton pump inhibitors, omeprazole or pantoprazole, and alendronate on the mechanical properties of long bones in bilaterally ovariectomized (OVX) rats.MethodsThe experiments were carried out on 3-month-old Wistar rats, divided into following groups: non-ovariectomized control rats, OVX control rats, OVX rats administered omeprazole or pantoprazole, OVX rats administered alendronate, OVX rats administered alendronate and omeprazole or pantoprazole. The drugs were administered to the rats for 28 days: alendronate at a dose of 3 mg/kg po, omeprazole or pantoprazole at a dose of 3 mg/kg ip. Mechanical properties of tibial metaphysis, femoral diaphysis and femoral neck were assessed. Bone macrometric parameters, mass and mass of bone mineral were also examined in the tibia and femur.ResultsEstrogen deficiency caused development of osteopenia with significant worsening of bone mechanical properties. Alendronate counteracted the deleterious changes in bone mechanical properties of the tibial metaphysis and femoral neck induced by estrogen deficiency. Pantoprazole worsened mechanical properties of the tibia in estrogen-deficient rats. Omeprazole or pantoprazole administered concurrently with alendronate attenuated the effect of alendronate on mechanical properties of the tibial metaphysis and femoral neck in ovariectomized rats. The unfavorable effect of pantoprazole was stronger than that of omeprazole.ConclusionProton pump inhibitors weakened the protective effect of alendronate on bone mechanical properties in estrogendeficient rats.  相似文献   
884.
The Joint Photographic Experts Group (JPEG) standard format is one of the most widely used in image compression technologies. More recently, JPEG2000 format has emerged as a state-of-the-art technology that provides substantial improvements in picture quality at higher compression ratios. However, there has been no attempt to date to determine which of the two compression formats produces less variability in the automated evaluation of immunohistochemically stained digital images in agreement with their compression rates and complexity degrees. The evaluation of Ki67 and FOXP3 immunohistochemical nuclear markers was performed in a total of 329 digital images: 47 were captured in uncompressed Tagged Image File Format (TIFF), 141 were converted to three JPEG compressed formats (47 each with 1:3, 1:23 and 1:46 compression) and 141 were converted to three JPEG2000 compressed formats (47 each with 1:3, 1:23 and 1:46 compression). The count differences between images in TIFF versus JPEG formats were compared with those obtained between images in TIFF versus JPEG2000 formats at the three levels of compression. It was found that, using JPEG2000 compression, the results of the stained nuclei count are close enough to the results obtained with uncompressed images, especially in highly complex images at minimum and medium compression. Otherwise, in images of low complexity, JPEG and JPEG2000 had similar count efficiency to that of the original TIFF images at all compression levels. These data suggest that JPEG2000 could give rise to an efficient means of storage, reducing file size and storage capacity, without compromise on the immunohistochemical analytical quality.  相似文献   
885.
Conjugation of anticancer drugs with different carriers has been extensively studied recently as a potential method of obtaining improved drug forms. The conjugation often results in the increase of the therapeutic effect, alteration of a toxicity profile, and/or selective targeting of therapeutic agent to the tissue of interest. We have synthesized mannan-methotrexate conjugate by means of methotrexate anhydride and studied its antitumor properties both in vitro and in vivo in comparison with free methotrexate. Mannan-methotrexate conjugate showed significantly improved antitumor activity compared to free methotrexate in the model of P388 mouse leukemia disseminated in the peritoneal cavity treated with intraperitoneally injected chemotherapy. Conversely, the antitumor effects of free methotrexate and mannan-methotrexate conjugate were comparable when leukemia was implanted subcutaneously and chemotherapy agents were administered intravenously. These results suggest that mannan-methotrexate conjugate should be further investigated as a potential therapeutic agent for intraperitoneally disseminated tumors.  相似文献   
886.
887.
Genetic profile od four-generation family with hypertrophic cardiomyopathy is presented. The alterations in the MYH7 gene sequences were identified. Genetic background of familial hypertrophic cardiomyopathy is reviewed and discussed.  相似文献   
888.
889.
Cancellous bone decreases and bone marrow fat content increases with age. Osteoblasts and adipocytes are derived from a common precursor, and growth hormone (GH), a key hormone in integration of energy metabolism, regulates the differentiation and function of both cell lineages. Since an age‐related decline in GH is associated with bone loss, we investigated the relationship between GH and bone marrow adiposity in hypophysectomized (HYPOX) rats and in mice with defects in GH signaling. HYPOX dramatically reduced body weight gain, bone growth and mineralizing perimeter, serum insulin‐like growth factor 1 (IGF‐1) levels, and mRNA levels for IGF‐1 in liver and bone. Despite reduced body mass and adipocyte precursor pool size, HYPOX resulted in a dramatic increase in bone lipid levels, as reflected by increased bone marrow adiposity and bone triglyceride and cholesterol content. GH replacement normalized bone marrow adiposity and precursor pool size, as well as mineralizing perimeter in HYPOX rats. In contrast, 17β ‐estradiol, IGF‐1, thyroxine, and cortisone were ineffective. Parathyroid hormone (PTH) reversed the inhibitory effects of HYPOX on mineralizing perimeter but had no effect on adiposity. Finally, bone marrow adiposity was increased in mice deficient in GH and IGF‐1 but not in mice deficient in serum IGF‐1. Taken together, our findings indicate that the reciprocal changes in bone and fat mass in GH signaling‐deficient rodents are not directly coupled with one another. Rather, GH enhances adipocyte as well as osteoblast precursor pool size. However, GH increases osteoblast differentiation while suppressing bone marrow lipid accumulation. © 2010 American Society for Bone and Mineral Research  相似文献   
890.
Adipose-derived mesenchymal stem cells (ASCs) possess immunosuppressive properties, but their activity is dependent on stimuli provided by local environment. It is possible that proinflammatory milieu of rheumatoid joint affects ASCs function. To verify this hypothesis, rheumatoid ASCs (RA-ASCs) and osteoarthritic ASCs (OA-ASCs) derived from infrapatellar fat pad (IPFP) of the knee joint have been compared. RA- and OA-ASCs isolated from patients were cultured in vitro. Their secretory and proliferative activity was measured. Peripheral blood mononuclear cells (PBMCs) from healthy donors were co-cultured with ASCs. Then, PBMCs proliferation was measured by 3H-thymidine incorporation method, cytokines secretion by immunoassays, T cells activation and regulatory T cells (Tregs) percentage – by flow cytometry. RA- and OA-ASCs properties in vitro were comparable, however, some differences in secretory activity occurred. RA- and OA-ASCs inhibited PBMCs proliferation and induced interleukin 10 production but up-regulated interleukin 17?A secretion and failed to limit release of other proinflammatory mediators (tumor necrosis factor [TNF], interferon γ [IFNγ], CCL5) by PBMCs. RA- and OA-ASCs did not suppress activation markers expression on T cells and did not trigger Tregs expansion. The present study shows that IPFP-ASCs from RA and OA patients have comparable functions in vitro. Their immunosuppressive activity seems to be impaired comparing to available data.  相似文献   
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