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61.
BACKGROUND: Kaposi's sarcoma is a multifocal lympho-angioproliferative disease that appears in elderly subjects of Mediterranean origin (classical form), young Africans and immunodepressed patients (as a result of organ transplantation or AIDS). In 1994, DNA sequences of a new human herpesvirus, called HHV-8, were detected in skin lesions and peripheral blood of patients with AIDS-related Kaposi's sarcoma by confirmational display analysis and polymerase chain reaction. OBJECTIVE: As HHV-8 in peripheral blood mononuclear cells is detected in about 50% of Mediterranean Kaposi's sarcoma patients and its presence fluctuates in time in the same patient, maybe its detection correlates with the clinical behaviour of the disease. METHODS: By using routine and nested polymerase chain reaction we evaluated the presence of HHV-8-specific DNA sequences in the skin lesions, perilesional healthy skin and peripheral blood mononuclear cells of a group of 40 HIV-negative patients with Mediterranean Kaposi's sarcoma. RESULTS: HHV-8 DNA sequences have been found in 40/40 (100%) lesional skin of Mediterranean Kaposi's sarcoma, in 35/40 (85%) perilesional apparently normal skin and in 24/40 (60%) peripheral blood monuclear cell samples. The results of polymerase chain reaction on peripheral blood monuclear cells were positive in 41% of the patients with slowly evolving disease as opposed to 74% of those with rapidly evolving disease, and in 47.6% of the patients with stage I-II disease as opposed to 73.6% of those with stage III-IV. CONCLUSION: The detection of HHV-8 in peripheral blood monuclear cells seems to correlate with the more aggressive stages and the rapid evolution behaviour of Mediterranean Kaposi's sarcoma.  相似文献   
62.
Background Bullous pemphigoid (BP) is a blistering skin disease caused by autoantibodies to hemidesmosomal proteins, with eosinophils participating in blister formation. Eosinophils are a source of tissue factor (TF), an initiator of blood coagulation. Objectives To evaluate the local and systemic activation of coagulation in BP. Methods We studied 20 patients with active BP (eight re‐evaluated during remission) and 40 controls. The coagulation markers prothrombin fragment F1+2 and d ‐dimer were measured in the plasma of all subjects and in both plasma and blister fluid of patients with BP. TF was evaluated immunohistochemically in skin specimens from the 20 patients and in 20 normal samples. Results F1+2 and d ‐dimer levels were higher in plasma of patients with BP (649 ± 96 pmol L?1 and 18·52 ± 3·44 nmol L?1, respectively) than in plasma of controls (157 ± 7 pmol L?1 and 1·42 ± 0·06 nmol L?1; P = 0·0001), and were very high in blister fluid (40 449 ± 3491 pmol L?1 and 1532·32 ± 262·81 nmol L?1; P = 0·0001). Plasma and blister fluid F1+2 and d ‐dimer levels paralleled blood and tissue eosinophilia and disease severity. In the eight patients re‐evaluated during remission, there was a marked reduction in F1+2 (from 1127 ± 144 to 287 ± 52 pmol L?1; P = 0·005) and d ‐dimer (from 24·03 ± 4·08 to 4·69 ± 1·51 nmol L?1; P = 0·029). Immunohistochemistry revealed strong TF reactivity in BP skin (P = 0·0001), and colocalization studies confirmed eosinophils as a source of TF. Conclusions The coagulation cascade is activated in BP and correlates with the severity of the disease and with eosinophilia, indicating that eosinophils play a role in coagulation activation via TF. The hypercoagulability may contribute to inflammation, tissue damage, blister formation and possibly thrombotic risk in BP.  相似文献   
63.
Reliable chemical sensors with high selectivity and sensitivity toward specific target molecules require rational synthesis of receptors, in-depth characterization of their complexation abilities and highly efficient transduction of the molecular recognition event. Here we report a steady-state and time-resolved fluorescence investigation of EtQxBox, a fluorescent conformationally blocked quinoxaline-based cavitand, aimed at assessing its selectivity toward aromatic versus non-aromatic analytes in solution. Fluorescence quenching of the EtQxBox in acetone is observed at increasing concentration of both aromatic (i.e. benzonitrile) and aliphatic (i.e. acetonitrile) compounds. The combination with fluorescence lifetime measurements permits to discriminate the predominantly static quenching of the aromatic analyte, due to non-fluorescent host–guest complex formation, from the mostly dynamic quenching of the non-aromatic compound, resulting from aspecific diffusive collisions between the fluorophore and the quencher. The equilibrium association constants for both the complexes have been estimated using Stern–Volmer model.

We investigate the role of combined static and dynamic quenching in fluorescence transduction of benzonitrile and acetonitrile complexation by a rigid quinoxaline-based cavitand.  相似文献   
64.
Journal of Thrombosis and Thrombolysis - To compare age at 1st ischaemic stroke (IS) in a cohort of juvenile (<?46 years of age) IS patients evaluated for the rs1801133...  相似文献   
65.
Chronic hepatitis C virus (HCV) infection is the principal etiology of cirrhosis and, ultimately, hepatocellular carcinoma (HCC). At present, approximately 71 million people are chronically infected with HCV, and 10%–20% of these are expected to develop severe liver complications throughout their lifetime. Scientific evidence has clearly shown the causal association between miRNAs, HCV infection and HCC. Although it is not completely clear whether miRNA dysregulation in HCC is the cause or the consequence of its development, variations in miRNA patterns have been described in different liver diseases, including HCC. Many studies have analyzed the importance of circulating miRNAs and their effect on cell proliferation and apoptosis. In this Review, we aim to summarize current knowledge on the association between miRNA, HCV and HCC from a diagnostic point of view, and also the potential implications for therapeutic approaches.  相似文献   
66.
The long-term changes of liver stiffness (LS) in patients who achieve viral clearance after direct-acting anti-HCV therapy remain undefined. We conducted a multicentre prospective study to investigate this aspect. Patients with HCV infection treated with DAAs were enrolled from six Italian centres; they underwent clinical, biochemical, ultrasound and transient elastography evaluations before treatment (T0), 12 weeks (SVR12) and 24 months (T24) after the end of therapy. Among the 516 consecutive patients enrolled, 301 had cirrhosis. LS significantly decreased from T0 to SVR (14.3 vs 11.1 kPa, p = .002), with a progressive reduction until T24 (8.7 kPa, p < .001). However, only patients with steatosis and those who developed HCC did not experience a late improvement in LS. Multivariate analysis of baseline and follow-up variables identified steatosis as the only independent predictor of failure of LS improvement (OR 1.802, p = .013). ROC curve analysis of the association of LS with the risk of developing HCC showed that SVR12 ≥14.0 kPa had the highest accuracy (sensitivity 82%, specificity 99%; AUC: 0.774). Multivariate analysis revealed that LS was the only variable independently associated with an increased risk of developing HCC (OR 6.470, p = .035). Achieving an SVR was associated with a progressive, long-term decline of LS, suggesting a late improvement in liver fibrosis, besides the resolution of inflammation. Fatty liver and the development of HCC interfered with late reduction of LS. Patients with an LS ≥14 kPa at 12 weeks after the end of treatment were at higher risk for developing HCC.  相似文献   
67.
Journal of Interventional Cardiac Electrophysiology - Implantable cardioverter defibrillators (ICD) are widely accepted therapy in children and adolescents who are survivors of cardiac arrest or...  相似文献   
68.
We report on 14 children (seven boys, seven girls) with chronic idiopathic thrombocytopenic purpura (ITP) refractory to multiple treatments, who were given a short-term therapy (range between 6 and 10 weeks) with high doses of cyclosporin A (CyA) (median, 10 mg/kg/d). Six patients experienced adverse events and one developed severe systemic mycosis during therapy. A complete response (CR) was observed in four patients and a partial response (PR) in three patients. Only the four CR patients, who were all girls, had a sustained response. These data suggest that CyA may be effective in some children with chronic symptomatic ITP.  相似文献   
69.
We have previously shown that the life cycles of several viruses are influenced by host-cell redox states. Reports of the antioxidant activities of the plant polyphenol resveratrol (RV) prompted us to investigate its effects on influenza virus replication in vitro and in vivo. We found that RV strongly inhibited the replication of influenza virus in MDCK cells but that this activity was not directly related to glutathione-mediated antioxidant activity. Rather, it involved the blockade of the nuclear-cytoplasmic translocation of viral ribonucleoproteins and reduced expression of late viral proteins seemingly related to the inhibition of protein kinase C activity and its dependent pathways. RV also significantly improved survival and decreased pulmonary viral titers in influenza virus-infected mice. No toxic effects were observed in vitro or in vivo. That RV acts by inhibiting a cellular, rather than a viral, function suggests that it could be a particularly valuable anti-influenza drug.  相似文献   
70.
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