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991.

Objective:

Follicular dendritic cells (FDCs) and interdigitating dendritic cells (IDCs) are dendritic cells found in lymphoid follicles, reactive follicles and in lymphomas. The goal of this study was to evaluate the presence and distribution of FDCs and IDCs in oral lymphomas.

Material and Methods:

Immunohistochemistry reactions were applied to 50 oral lymphomas using the antibodies anti-CD21, anti-CD35 and anti-caldesmon to FDCs, and anti-S100 protein to IDCs. Caldesmon+/FDCs and S100+/IDCs were quantified in Imagelab® software.

Results:

FDCs revealed by CD21 and CD35 were positively stained in two cases of diffuse large B-cell lymphoma, one MALT lymphoma, and in one case of mantle cell lymphoma. FDCs were immunopositive to caldesmon in all cases, as well as IDCs to S100 protein. Burkitt lymphoma presented a lower amount of caldesmon+/FDCs and S100+/IDCs than diffuse large B-cell lymphoma and plasmablastic lymphoma of the oral mucosa type.

Conclusions:

The microenvironment determined by neoplastic lymphoid cells in oral lymphomas is responsible by the development and expression of dendritic cells types.  相似文献   
992.
Introduction: Polymorphonuclear neutrophil (PMN) dysfunctions have been associated with severe forms of periodontitis. This study evaluated the correlation between PMN phagocytosis and oxidative burst with the subgingival microbiota of patients with generalized aggressive periodontitis (GAgP). Methods: Heparinized peripheral blood samples were obtained from 18 GAgP patients and 11 periodontally healthy (PH) subjects, and PMNs were isolated on a Ficoll–Hypaque gradient. For phagocytosis analysis, PMNs were incubated with fluorescein‐labeled Staphylococcus aureus. The oxidative burst was evaluated by incubation of PMNs with dihydroethidium and activation by S. aureus. The assays were examined using flow cytometry. Subgingival biofilm samples were obtained from periodontal sites with and without periodontitis and 24 species were detected by checkerboard. Results: A significantly lower phagocytosis rate was observed for patients with GAgP compared with PH subjects over time (P < 0.05). No differences between groups were found for superoxide production. GAgP patients presented significantly higher prevalence and levels of Porphyromonas gingivalis, Tannerella forsythia, and Aggregatibacter actinomycetemcomitans serotype b than controls (P < 0.05). Significant negative correlations between T. forsythia and P. gingivalis and PMN functions were observed. Conclusions: GAgP subjects presented diminished phagocytic activity of peripheral PMNs and high prevalence and levels of classical periodontal pathogens.  相似文献   
993.
Findings on the association between alcohol consumption and bladder cancer are inconsistent. We investigated that association in the European Prospective Investigation into Cancer and Nutrition cohort. We included 476,160 individuals mostly aged 35–70 years, enrolled in ten countries and followed for 13.9 years on average. Hazard ratios (HR) for developing urothelial cell carcinoma (UCC; 1,802 incident cases) were calculated using Cox proportional hazards models. Alcohol consumption at baseline and over the life course was analyzed, as well as different types of beverages (beer, wine, spirits). Baseline alcohol intake was associated with a statistically nonsignificant increased risk of UCC (HR 1.03; 95% confidence interval (CI) 1.00–1.06 for each additional 12 g/day). HR in smokers was 1.04 (95% CI 1.01–1.07). Men reporting high baseline intakes of alcohol (>96 g/day) had an increased risk of UCC (HR 1.57; 95% CI 1.03–2.40) compared to those reporting moderate intakes (<6 g/day), but no dose–response relationship emerged. In men, an increased risk of aggressive forms of UCC was observed even at lower doses (>6 to 24 g/day). Average lifelong alcohol intake was not associated with the risk of UCC, however intakes of spirits > 24 g/day were associated with an increased risk of UCC in men (1.38; 95% CI 1.01–1.91) and smokers (1.39; 95% CI 1.01–1.92), compared to moderate intakes. We found no association between alcohol and UCC in women and never smokers. In conclusion, we observed some associations between alcohol and UCC in men and in smokers, possibly because of residual confounding by tobacco smoking.  相似文献   
994.
995.
Mucoepidermoid carcinomas (MECs) are the most common malignancy of the salivary glands demonstrating a wide range of histologic variants and behavior. However, the sclerosing mucoepidermoid carcinoma (SMEC), a morphologic variant of this tumor is extremely rare and has been described almost exclusively in the major glands. The prominent sclerosis observed may obscure its typical morphological feature resulting in a diagnostic challenge. We describe herein a case of SMEC in a 43-year-old-woman, occurring in the minor salivary glands of palate. To our knowledge only 13 cases have been reported until this moment, being only 2 in minor salivary glands. We also performed the immunohistochemical evaluation of c-erbB-2 and Ki-67, searching for an association with the histopathological findings and behavior.  相似文献   
996.
Approximately 300 million non-cardiac surgeries are performed annually worldwide and adverse cardiovascular events are the main cause of morbidity and mortality in the peri- and postoperative period. Myocardial injury after non-cardiac surgery (MINS) is a new clinical entity associated with adverse cardiovascular outcomes. MINS is defined as myocardial injury that can result in necrosis due to ischemia, marked by increase in biomarker levels. It has prognostic relevance and occurs within up to 30 days after non-cardiac surgery. The diagnostic criteria for MINS are an elevated postoperative measure of troponin judged as secondary to myocardial ischemia, i.e., with no evidence of a non-ischemic etiology, during or within 30 days after non-cardiac surgery, and without the requirement of an ischemic symptom or electrocardiographic finding of ischemia. Recently, patients at higher risk for MINS have been recognized using clinical variables and biomarkers and established protocols for greater surveillance in relation to electrocardiographic monitoring and cardiac troponin dosage. Elderly patients with previous atherosclerotic disease need to measure troponin daily in the postoperative period. The aim of the present work is to describe this new public health problem, its clinical impact and contemporary therapeutic approach.  相似文献   
997.
998.
Studies in adult inflammatory bowel disease (IBD) patients have highlighted associations with genetic and serologic markers and suggest an association with disease location, behaviour and natural history. Data on patients with Crohn’s disease (CD, n = 80), ulcerative colitis (UC, n = 15) and indeterminate colitis (n = 4) were collected. All individuals were analysed for CARD15 R702W, G908R and L1007fs for toll-like receptor 4 (TLR4) Asp299Gly and for anti-Saccharomyces cerevisiae antibodies (ASCA) and atypical perinuclear antineutrophil cytoplasmatic antibodies (pANCA). After a mean of 10.7 years of follow up, the disease behaviour changed in 45% of CD patients, in contrast to disease location, where only 12.5% had a change (p < 0.001). The younger the age at diagnosis, the more patients presented with colonic disease (p = 0.021). Also, more TLR4 Asp299 Gly variants were found when the age at onset was younger (p = 0.018). A large number of concomitant diseases were observed. There was no difference in the prevalence of TLR4 variants nor ASCA or pANCA between the patients with or without concomitant diseases. Patients who progressed more often needed surgery as compared to patients who remained free of stenosing or fistulising disease (27/32 or 84% versus 3/35 or 8.6%, respectively, p < 0.0001) and more often had concomitant immune-mediated diseases and a trend for more seroreactivity towards ASCA.  相似文献   
999.
Tumour cells are known to be highly glycolytic, thus producing high amounts of lactic acid. Monocarboxylate transporters (MCTs), by promoting the efflux of the accumulating acids, constitute one of the most important mechanisms in the maintenance of tumour intracellular pH. Since data concerning MCT expression in colorectal carcinomas (CRC) are scarce and controversial, the present study aimed to assess the expressions of MCT1, 2, and 4 in a well characterized series of CRC and assess their role in CRC carcinogenesis. CRC samples (126 cases) were analyzed for MCT1, MCT2, and MCT4 immunoexpression and findings correlated with clinico-pathological parameters. Expression of all MCT isoforms in tumour cells was significantly increased when compared to adjacent normal epithelium. Remarkably, there was a significant gain of membrane expression for MCT1 and MCT4 and loss of plasma membrane expression for MCT2 in tumour cells. Plasma membrane expression of MCT1 was directly related to the presence of vascular invasion. This is the larger study on MCT expression in CRC and evaluates for the first time its clinico-pathological significance. The increased expression of these transporters suggests an important role in CRC, which might justify their use, especially MCT1 and MCT4, as targets in CRC drug therapy.  相似文献   
1000.
Herein, we described an experimental model of high-dose ethanol (EtOH) administration, able to induce in vitro impairment in macrophage phagocytic capacity, already observed at 24 h after the last EtOH administration. This phenomenon was characterized by enlarged time required for adhesion and internalization events. Parallel studies documented an overall impaired production of interleukin (IL)-6 and nitric oxide (NO) production by peritoneal macrophages in EtOH-treated mice following interferon (IFN)-γ and lipopolysaccharide (LPS) stimuli. Although the impaired IL-6 response could not be restored by any of the experimental conditions tested, the lower NO response to INF-γ and LPS was overturned by simultaneous IFN-γ/LPS stimuli. It was interesting to notice that high-dose EtOH administration drives peritoneal macrophages towards long-term impairment in phagocytosis capacity with slower adhesion time, but with no impact on the time required for internalization. Moreover, 30 days after the last EtOH administration, lower IL-6 response to INF-γ and impaired NO production were still observed in response to IFN-γ/LPS stimuli, with the IL-6 response to IFN-γ being restored by IFN-γ/LPS stimuli. Histological studies showed that high-dose EtOH administration led to long-term in vivo impairment of antigen-clearance following OVA-driven delayed-type-hypersensitivity induction, characterized by the presence of a large amount of unprocessed OVA surrounded by dermal inflammatory infiltrate, suggesting defective activity of antigen-presenting cells. Together, these findings supported our hypothesis that the poor antigen clearance in vivo may be related to the impaired macrophage function in vitro . These observations in the murine experimental model may reflect some of the consequences of EtOH consumption by humans.  相似文献   
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