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21.
报告1例青少年骨性Ⅱ类,上颌发育过度,下颌发育不足的双期矫治病例。通过一期使用功能性活动矫治器促进下颌生长、二期直丝弓固定矫治,改善上颌前突,取得较满意的效果。  相似文献   
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This is a case report of allergic fungal rhinosinusitis caused by Schizophyllum commune (S. commune) identified in a patient's nasal mucus and environmental soil sample using (r)DNA sequencing. Although filamentous basidiomycetes, including S. commune, are known as environmental pathogens causing allergic respiratory diseases worldwide, many patients with infections caused by S. commune have not been correctly diagnosed. Repeated exposures to environmental floating fungi supposedly make an easy sensitization and colonization of fungi in the nasal passages, resulting in the onset of allergic fungal rhinosinusitis due to S. commune in our living environments. This report indicates the importance of reconsidering allergic respiratory diseases associated with our living environments.  相似文献   
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Bisphenol A (BPA) is a widespread environmental endocrine disrupting chemical. Although many animals and in vitro studies reported that BPA may affect female fertility through the effect on maturing oocytes and meiotic cell division, but the data from human studies are limited and inconclusive. The study was conducted to examine the association between urinary BPA concentration and in vitro reproductive outcomes (metaphase II (MII) oocyte yield, top quality embryo, fertilization rate, implantation rate and clinical pregnancy) among women from an infertility clinic.The study participants were enrolled in the Infertility Center in Poland. 450 women aged 24-44 (n = 674 IVF cycles) provided urine samples. The urinary concentrations of BPA were evaluated using validated gas chromatography ion-tap mass spectrometry method. Clinical outcomes of IVF treatment were abstracted from patients electronic chart records. To assess the relationship between urinary BPA concentrations early examined reproductive outcomes generalized linear mixed models were used.The detection rate of BPA in urine samples was 98% and the geometric mean 1.59 ± 2.15 ng/ml. A significant decrease was observed between urinary concentration of BPA and implantation (p = 0.04) and decreased MII oocyte count (p = 0.03). There was no association between other examined IVF outcomes: embryo quality, fertilization rate and clinical pregnancy and BPA exposure.Exposure to BPA may have a negative effect during the early stages of human development. The studies among the larger and more diverse population are needed to confirm the results.  相似文献   
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《Toxicology letters》2014,229(1):284-291
Dichlorodiphenyltrichloroethane (DDT), an organochlorine pollutant, is associated with several types of cancer. However, the relationship between DDT and colorectal cancer is uncertain. In this study, the impact of p,p′-DDT on colorectal cancer growth was evaluated using both in vitro and in vivo models. Our results indicated that the proliferation of human colorectal adenocarcinoma DLD1 cells was significantly promoted after exposed to low concentrations of p,p′-DDT ranging from 10−12 to 10−7 M for 96 h. Exposure to p,p′-DDT from 10−10 to 10−8 M led to upregulation of phospho-GSK3β (Ser9), β-catenin, c-Myc and cyclin D1 in DLD1 cells. RNA interference of β-catenin inhibited the proliferation of DLD1 cells stimulated by p,p′-DDT. Inhibiting of estrogen receptors (ERs) had no significant effect on the action of p,p′-DDT. Treatment with p,p′-DDT induced production of intracellular reactive oxygen species (ROS) and inhibited superoxide dismutase (SOD) activity in DLD1 cells. Treatment with N-acetyl-L-cysteine (NAC), a ROS inhibitor, suppressed the induction of Wnt/β-catenin signaling and DLD1 cell proliferation by p,p′-DDT. Moreover, in a mouse xenograft model, 5 nmol/kg p,p′-DDT resulted in increased tumor size, oxidative stress and Wnt/β-catenin signaling. These results indicated that low concentrations of p,p′-DDT promoted colorectal cancer growth through Wnt/β-catenin signaling, which was mediated by oxidative stress. The finding suggests an association between low concentrations of p,p′-DDT exposure and colorectal cancer progression.  相似文献   
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Background and study aimsPatients with non-alcoholic fatty liver disease (NAFLD) exhibit features of metabolic syndrome, including a high body mass index, central obesity, high blood pressure, and abnormal lipid profile values. Orlistat, an intestinal lipase enzyme inhibitor, improves insulin resistance. We aimed to investigate the effects of short-term therapy with orlistat on the components of metabolic syndrome associated with NAFLD and explore its effect on liver fibrosis scores.Patients and methodsAn open-label placebo-controlled clinical study using orlistat for 12 weeks was carried out on 50 patients with NAFLD. They were divided into a placebo group (Group I) and an orlistat treatment group (120 mg per day, Group II). The diagnosis of NAFLD was made by ultrasonography and laboratory investigations. Anthropometric and blood pressure measurements and hepatic liver enzymes, fasting lipids, and blood glucose levels were determined before and after treatment. Lipid indices including cholesterol (Chol-I), triglyceride (TG-I), triglyceride-glucose (TYG-I), and the scores for lipid fibrosis using the NAFLD fibrosis score (NFS) and Fibrosis-4 score (Fib-4) were also determined.ResultsOrlistat significantly improved the anthropometric and metabolic indices (TG-I, TYG-I) and liver enzymes. Orlistat demonstrated a favorable impact on the NAS and Fib-4 scores for liver fibrosis.ConclusionOrlistat improves the components of metabolic syndrome, leading to the improvement of insulin resistance and thereby improves fatty infiltration of the liver. To a lesser extent, orlistat improved the liver fibrosis scores.  相似文献   
28.
Multiple sclerosis (MS) is a chronic demyelinating disease of the central nervous system characterized by recurrent and progressive demyelination, neuroinflammation and oligodendrocyte loss. The cuprizone (CPZ) model is characterized by primary and reversible demyelination, accompanied by oligodendrocyte loss and neuroinflammation. In the current study, we explored the efficiency of Bilobalide in the demyelination and remyelination. The results demonstrate that Bilobalide improved behavioral abnormality and promoted remyelination in the corpus callosum by using Luxol Fast Blue, Black Gold II and myelin basic protein (MBP) staining. We for the first time found that CPZ caused the splenic atrophy and induced the formation of myelin oligodendrocyte glycoprotein (MOG) antibody, which was attenuated by Bilobalide. Thus, Bilobalide decreased the loss of O4+ oligodendrocytes possibly through MOG antibody-dependent cell cytotoxicity. Bilobalide also prevented the infiltration of CD4+ T cells, CD68+ macrophages and B220+ B cells within the brain, and reduced the inflammatory microenvironment mediated with Iba1+iNOS+ and Iba1+NF-kB+ microglia after CPZ challenge, accompanied by the inhibition of IL-1β and IL-6 in the brain. These results identify a potent therapeutic efficiency for Bilobalide and highlight clear pleiotropic effects of the compound beyond specific autoantibody and inflammatory microenvironment in CPZ-mediated demyelination.  相似文献   
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We aimed to determine the survival benefits of chemotherapy (CT) added to radiotherapy (RT) in different risk groups of patients with early-stage extranodal nasal-type NK/T-cell lymphoma (ENKTCL), and to investigate the risk of postponing RT based on induction CT responses. A total of 1360 patients who received RT with or without new-regimen CT from 20 institutions were retrospectively reviewed. The patients had received RT alone, RT followed by CT (RT + CT), or CT followed by RT (CT + RT). The patients were stratified into different risk groups using the nomogram-revised risk index (NRI). A comparative study was performed using propensity score-matched (PSM) analysis. Adding new-regimen CT to RT (vs RT alone) significantly improved overall survival (OS, 73.2% vs 60.9%, P < .001) and progression-free survival (PFS, 63.5% vs 54.2%, P < .001) for intermediate-risk/high-risk patients, but not for low-risk patients. For intermediate-risk/high-risk patients, RT + CT and CT + RT resulted in non-significantly different OS (77.7% vs 72.4%; P = .290) and PFS (67.1% vs 63.1%; P = .592). For patients with complete response (CR) after induction CT, initiation of RT within or beyond three cycles of CT resulted in similar OS (78.2% vs 81.7%, P = .915) and PFS (68.2% vs 69.9%, P = .519). For patients without CR, early RT resulted in better PFS (63.4% vs 47.6%, P = .019) than late RT. Risk-based, response-adapted therapy involving early RT combined with CT is a viable, effective strategy for intermediate-risk/high-risk early-stage patients with ENKTCL in the modern treatment era.  相似文献   
30.
Native cholera toxin (CT) and its mutated form (CT-2*) without ADP-ribosyltransferase activity differ in their immunomodulatory effects on host cells, and the mechanisms of these differences are poorly understood. In this study, we demonstrated that CT-2* induced higher levels of cytokine production and down-regulated ex-vivo apoptosis of splenocytes from C57BL/6 mice. After exposure of the splenocytes ex-vivo to CT or CT-2* (2 μg/ml) for 48 h, CT-2* stimulated expression of the toll-like receptor (TLR-4) gene was much higher and the cells produced increased levels of interleukin (IL)-12, interferon (IFN)-γ, and tumor necrosis factor (TNF)-α, compared to splenocytes of mice exposed to native CT. We confirmed these findings by observing that CT-2*, induced much lower levels of IL-12, IFN-γ, and TNF-α in a TLR-4 knockout macrophage cell line derived from C57BL/6 mice. In addition, while CT is known to stimulate apoptosis in splenocytes, we observed that CT-2* significantly down-regulated apoptosis (4.2%), compared to splenocytes exposed to CT (18.7%) or PBS (negative control, 8.5%). On the contrary, we noted both native CT and CT-2* to exhibit similar levels of apoptosis in TLR-4−/− cell line. Overall, the evidence supports the conclusion that CT-2* modulated cytokine production and apoptosis in splenocytes of mice possibly through the TLR-4 signaling pathway.  相似文献   
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