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41.
42.
Spyridon Gougousis Savvas Petanidis Alexandros Poutoglidis Nikolaos Tsetsos Paraskevas Vrochidis Ioannis Skoumpas Nektarios Argyriou Theodora Katopodi Kalliopi Domvri 《Oncology Letters》2022,23(6)
Head and neck cancer (HNC) comprises a heterogeneous variety of malignant tumors, characterized by a relatively high tumor mutation burden. Previous data have revealed that immune system dysfunction appears to serve a key role in the development and progression of HNC and established immunosuppression is vital for evading the host immune response. Despite progress in chemotherapy and radiotherapy, the survival rate of patients with HNC is still low. Therefore, the present review discusses the development of novel immunotherapy approaches based on the various immune cell signaling routes that trigger drug resistance and immunosuppression. Additionally, the present review discusses the epigenetic alterations, including DNA methylation, histone modifications, chromatin remodeling and non-coding RNAs that drive and support HNC progression. Furthermore, the role of cancer-associated fibroblasts, tumor macrophages and myeloid cells in tumor-related immunosuppression are considered. Specifically, the molecular immune-related mechanisms in the tumor microenvironment, which lead to decreased drug sensitivity and tumor relapse, and strategies for reversing drug resistance and targeting immunosuppressive tumor networks are discussed. Deciphering these molecular mechanisms is essential for preclinical and clinical investigations in order to enhance therapeutic efficacy. Furthermore, an improved understanding of these immune cell signaling pathways that drive immune surveillance, immune-driven inflammation and tumor-related immunosuppression is necessary for future personalized HNC-based therapeutic approaches. 相似文献
43.
Nikolaos Mertziotis Diomidis Kozyrakis Andreas Petrolekas Maria Terzi Nikiforos Kapranos 《Canadian Urological Association journal》2012,6(6):E274-E276
A 62-year old male patient presented complaining of intermittent macroscopic hematuria. The ultrasonographic investigation revealed a hydronephrosis of remarkable degree with indiscrete renal parenchyma. The abdominal computed tomography scan identified a ureteral lesion with proximal dilatation, hydronephrosis and a functionless ipsilateral renal unit. The retrograde urography showed a 4-cm lesion with multiple filling defects and a smooth contour. The endoscopic examination showed an exophytic lesion, highly suspicious for malignancy. Urine cytology revealed atypia. Right nephroureterectomy was performed and the pathology revealed a ureteral inverted papilloma (UIP). Polymerase chain reaction examination for the presence of human papilloma virus, using GP5+/6+ consensus primers, was negative. The presence UIP should be considered in patients with urotheleal lesions in the ureter when the diagnostic workup for malignancy is inconclusive. The clinical course of the disease seems to be favorable. 相似文献
44.
Andriana C. Kaliora Aggeliki M. Kountouri Vaios T. Karathanos Lemonica Koumbi Nikolaos G. Papadopoulos Nikolaos K. Andrikopoulos 《Nutrition and cancer》2013,65(6):792-799
Currants and Sultanas (Vitis vinifera L.) are dried vine products produced in Greece and used broadly in the Mediterranean diet. We aimed to investigate the gastric cancer preventive activity of methanol extracts obtained from currants from three different origins in Greece (Vostizza, Nemea, and Messinia) as well as methanol extracts obtained from Sultanas cultivated in the island of Crete as to inhibition of cell proliferation, induction of apoptosis, and inhibition of inflammation. All extracts from 500 μg dried raisins studied suppressed cell proliferation, significantly those obtained from Sultanas from Crete and currants from Nemea. Flow cytometric analysis of Annexin-V labeled cells indicated that Cretan Sultana, Nemea, and Messinia currants at 500 μg dried product/ml medium significantly induced cell death. All extracts from 500 μg dried raisins statistically decreased protein and mRNA levels of ICAM-1 in TNF-alpha stimulated cells. Measurement of IL-8 protein levels and quantification for IL-8 mRNA showed no significant decrease. These results indicate that the methanol extracts from currants, rich in phenolic compounds, exhibit cancer preventive efficacy by limiting cell proliferation, inducing cell death, and suppressing ICAM-1 levels in AGS cells. 相似文献
45.
Shalaila S. Haas Linda A. Antonucci Julian Wenzel Anne Ruef Bruno Biagianti Marco Paolini Boris-Stephan Rauchmann Johanna Weiske Joseph Kambeitz Stefan Borgwardt Paolo Brambilla Eva Meisenzahl Raimo K. R. Salokangas Rachel Upthegrove Stephen J. Wood Nikolaos Koutsouleris Lana Kambeitz-Ilankovic 《Neuropsychopharmacology》2021,46(4):828
Two decades of studies suggest that computerized cognitive training (CCT) has an effect on cognitive improvement and the restoration of brain activity. Nevertheless, individual response to CCT remains heterogenous, and the predictive potential of neuroimaging in gauging response to CCT remains unknown. We employed multivariate pattern analysis (MVPA) on whole-brain resting-state functional connectivity (rsFC) to (neuro)monitor clinical outcome defined as psychosis-likeness change after 10-hours of CCT in recent onset psychosis (ROP) patients. Additionally, we investigated if sensory processing (SP) change during CCT is associated with individual psychosis-likeness change and cognitive gains after CCT. 26 ROP patients were divided into maintainers and improvers based on their SP change during CCT. A support vector machine (SVM) classifier separating 56 healthy controls (HC) from 35 ROP patients using rsFC (balanced accuracy of 65.5%, P < 0.01) was built in an independent sample to create a naturalistic model representing the HC-ROP hyperplane. This model was out-of-sample cross-validated in the ROP patients from the CCT trial to assess associations between rsFC pattern change, cognitive gains and SP during CCT. Patients with intact SP threshold at baseline showed improved attention despite psychosis status on the SVM hyperplane at follow-up (p < 0.05). Contrarily, the attentional gains occurred in the ROP patients who showed impaired SP at baseline only if rsfMRI diagnosis status shifted to the healthy-like side of the SVM continuum. Our results reveal the utility of MVPA for elucidating treatment response neuromarkers based on rsFC-SP change and pave the road to more personalized interventions.Subject terms: Predictive markers, Psychosis 相似文献
46.
Erika J. Wolf Ci-Di Chen Xiang Zhao Zhenwei Zhou Filomene G. Morrison Nikolaos P. Daskalakis Annjanette Stone Steven Schichman Jaclyn Garza Grenier Dana Fein-Schaffer Bertrand R. Huber Traumatic Stress Brain Research Group Carmela R. Abraham Mark W. Miller Mark W. Logue 《Neuropsychopharmacology》2021,46(4):721
47.
48.
Petros Ypsilantis Maria Lambropoulou Ioannis Tentes Konstantinos Anagnostopoulos Christina Tsigalou Nikolaos Papadopoulos Alexandros Kortsaris Constantinos Simopoulos 《Journal of gastroenterology and hepatology》2009,24(4):623-632
Background and Aim: We investigated the role of the prophylactic administration of the antioxidant 2‐mercaptoethane sulfonate (mesna) on the hepatocyte‐regenerating capacity following partial hepatectomy (PH) with concurrent Pringle maneuver. Methods: Wistar rats were subjected to PH (70% hepatectomy), 30 min Pringle maneuver, PH plus Pringle with or without mesna pretreatment (400 mg/kg, per os, 3 h before Pringle), or sham operation. At 24 h, 48 h, 72 h, and 1 week after operation, relative liver weight, hepatocyte mitotic activity (mitotic index), the histopathological score and serum aspartate aminotransferase, and alanine aminotransferase concentrations were assessed. At 1 h after operation, oxidative stress markers (glutathione to glutathione disulfide ratio, malondialdehyde concentration, and superoxide dismutase activity) and nuclear factor‐κB (NF‐κB) activity were assessed. Results: Hepatectomy stimulated the regenerating process and induced mild oxidative stress and the activation of NF‐κB in hepatocytes, while causing tissue injury in the remnant liver. When PH was performed under Pringle maneuver, hepatocyte mitotic activity was substantially suppressed, although Pringle alone initiated a delayed regenerating response. Furthermore, Pringle maneuver deteriorated oxidative stress markers, markedly increased NF‐κB activity, and aggravated tissue injury, as compared to hepatectomy alone. Mesna pretreatment prevented the Pringle‐induced antimitotic effect and the induction of oxidative stress, inhibited the activation of NF‐κB, while attenuating liver injury after PH under Pringle. Conclusion: The excessive activation of NF‐κB is related to the suppression of hepatocyte‐regenerating activity following PH with concurrent liver ischemia. Mesna pretreatment protects the liver against the Pringle‐induced antimitotic effect after PH via the prevention of oxidative stress and the inhibition of NF‐κB activation. 相似文献
49.
Type 1 and type 2 cytokine-producing CD4+ and CD8+ T cells in primary antiphospholipid syndrome 总被引:1,自引:0,他引:1
Karakantza M Theodorou GL Meimaris N Mouzaki A John E Andonopoulos AP Maniatis A 《Annals of hematology》2004,83(11):704-711
Antiphospholipid syndrome (APS) is an autoimmune condition characterized by thrombosis and/or recurrent fetal loss as well as the presence of autoantibodies against epitopes present on phospholipid-binding proteins. The role of cellular immunity in the pathogenesis of the syndrome remains unclear. We studied the cellular phenotype and the production of type 1 [interferon (IFN)-, interleukin (IL)-2] and type 2 (IL-4, IL-10) cytokines by CD4+ and CD8+ T-lymphocyte subsets in 13 patients with untreated primary APS (PAPS) and in 32 healthy controls. The production of cytokines was determined in T cells after a 5-h culture with or without mitogenic stimulation using a flow cytometric method of intracellular cytokine staining. In six of the patients these studies were repeated 6 months later. In PAPS patients we found a reduced percentage of circulating CD4+CD45RA+ and an increased percentage and absolute number of CD8+HLA-DR+ cells. A type 1 response was observed in the patients unstimulated cells, indicated by an increase in IFN--producing CD8+, IL-2-producing CD4+ T cells, and a decrease in IL-4-producing CD4+ and CD8+ T cells. Similar results were obtained in the patients at follow-up. Taken together, these results suggest a chronic in vivo stimulation of CD4+ and CD8+ T cells in PAPS patients exhibiting a type 1 polarization. Changes of cellular immunity may contribute to the pathogenesis of the clinical manifestations of the syndrome and might be proven to be useful targets for therapeutic interventions in the future. 相似文献
50.
Endoscopic management and long-term follow-up of Dieulafoy's lesions in the upper GI tract 总被引:15,自引:0,他引:15
Kasapidis P Georgopoulos P Delis V Balatsos V Konstantinidis A Skandalis N 《Gastrointestinal endoscopy》2002,55(4):527-531
BACKGROUND: The aim of this study was to retrospectively evaluate the short-and long-term effectiveness of different methods of endoscopic treatment for bleeding Dieulafoy's lesions. METHODS: Patients were allocated into 2 groups according to the hemostatic method applied: (1) injection group (epinephrine and/or ethanolamine oleate), and (2) thermal coagulation group (heat probe), either alone or combined with epinephrine injection. The combination of epinephrine and ethanolamine oleate was used in 5 patients, epinephrine alone in 3, ethanolamine oleate alone in one, heat probe and epinephrine in 8, and heat probe alone in 1 patient. RESULTS: Dieulafoy's lesions were found in 18 (1%) of 1750 patients with acute nonvariceal upper GI bleeding. Comorbid conditions were present in 5 (28%) patients. Initial hemostasis was achieved endoscopically in 13 patients (72%) and permanent hemostasis in 17 patients (94%). Bleeding recurred in 5 patients (2 with concomitant disease) in the injection group; 3 were successfully retreated by heat probe coagulation and epinephrine injection, 1 with hemoclip application and 1 by surgery. There was no recurrent bleeding in thermal treatment group. Thermal treatment was significantly superior to injection (p = 0.0029). CONCLUSIONS: Endoscopic thermal coagulation with or without epinephrine injection should be the initial treatment of choice for Dieulafoy's lesions. Mortality is lowest in patients with no significant comorbidity and an unremarkable medical history. 相似文献