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61.
PURPOSE: To evaluate the prognostic value of P-glycoprotein and clinicopathologic parameters in a large series of high-grade osteosarcoma (OS) patients treated at the Rizzoli Institute. PATIENTS AND METHODS: With the use of immunohistochemistry, P-glycoprotein was assessed in 149 patients with primary, nonmetastatic, high-grade OS who were homogeneously treated with chemotherapy protocols based on doxorubicin, high-dose methotrexate, and cisplatin and the addition of ifosfamide in the postoperative phase. RESULTS: P-glycoprotein positivity was found in 47 of 149 cases (32%) and was significantly associated with a higher incidence of relapse and a worse outcome, as was age younger than 12 years and tumor volume greater then 150 mL at diagnosis. Multivariate analysis further confirmed the prognostic value of these parameters, which all were independent adverse prognostic factors. Event-free survival and proportional hazards regression analyses confirmed that overexpression of P-glycoprotein at clinical onset is the most important adverse prognostic factor for high-grade OS patients treated with these chemotherapy protocols. CONCLUSION: Increased P-glycoprotein levels, together with tumor volume and age, should be taken into consideration to identify, at time of diagnosis, subgroups of OS patients with a higher risk of recurrence. This subgroup identification will constitute the basis for drawing individualized treatment protocols on the basis of risk evaluation, with the aim of using more aggressive chemotherapy, or combination chemotherapy with other adjuvants, only in those patients for which more aggressive regimens are strictly necessary and warranted.  相似文献   
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63.
Objective To assess the results of a policy of tailored conservative surgical management for young women with stage I ovarian carcinomas.
Design Retrospective study.
Participants Ninety-nine women aged 40 years or younger who underwent either primary surgery in our department or were referred after primary surgery performed elsewhere.
Methods Of the 99 women in our study, 56 underwent fertility-sparing surgery and 43 more radical surgery. Minimal requirements for conservative management were adequate staging and complete information about the therapeutic options. Factors important in the choice of the treatment were, age, wish to preserve fertility, histologic type and grade, and the stage of the tumour.
Results Conservative treatment was conducted in 84% of nulliparous and in 33% of parous women; 62% of grade 1 tumours, 48% of grade 2, and 50% of grade 3 were treated conservatively. With a median follow up of seven years, we observed five recurrences (9%) of carcinoma in women treated conservatively and five (12%) in those treated more radically. Two women (one in each treatment arm) were saved after recurrence. Two recurrences after conservative surgery involved the residual ovary (3.6%). Two women developed borderline tumour in the contralateral ovary and both were treated by surgery.
Conclusion After adequate staging and accurate information is given to the patient, conservative treatment may be safe in some women with early ovarian cancer. The risk of recurrence in the contralateral ovary is low. Conservative surgery may be also considered in some Stage I grade 3 tumours and in some women with stage IC tumours.  相似文献   
64.
BackgroundRisk-adjusted cancer screening and prevention is a promising and continuously emerging option for improving cancer prevention. It is driven by increasing knowledge of risk factors and the ability to determine them for individual risk prediction. However, there is a knowledge gap between evidence of increased risk and evidence of the effectiveness and efficiency of clinical preventive interventions based on increased risk. This gap is, in particular, aggravated by the extensive availability of genetic risk factor diagnostics, since the question of appropriate preventive measures immediately arises when an increased risk is identified. However, collecting proof of effective preventive measures, ideally by prospective randomized preventive studies, typically requires very long periods of time, while the knowledge about an increased risk immediately creates a high demand for action.SummaryTherefore, we propose a risk-adjusted prevention concept that is based on the best current evidence making needed and appropriate preventive measures available, and which is constantly evaluated through outcome evaluation, and continuously improved based on these results. We further discuss the structural and procedural requirements as well as legal and socioeconomical aspects relevant for the implementation of this concept.  相似文献   
65.
Deep vein thrombosis results from the cooperative action of leukocytes, platelets, and endothelial cells. The proline-rich tyrosine kinase Pyk2 regulates platelet activation and supports arterial thrombosis. In this study, we combined pharmacological and genetic approaches to unravel the role of Pyk2 in venous thrombosis. We found that mice lacking Pyk2 almost completely failed to develop deep venous thrombi upon partial ligation of the inferior vena cava. Pyk2-deficient platelets displayed impaired exposure of phosphatidylserine and tissue factor expression by endothelial cells and monocytes was completely prevented by inhibition of Pyk2. In human umbilical vein endothelial cells (HUVEC), inhibition of Pyk2 hampered IL-1β-induced expression of VCAM and P-selectin, and von Willebrand factor release. Pyk2-deficient platelets showed defective adhesion on von Willebrand factor and reduced ability to bind activated HUVEC under flow. Moreover, inhibition of Pyk2 in HUVEC strongly reduced platelet adhesion. Similarly, Pyk2-deficient neutrophils were unable to efficiently roll and adhere to immobilized endothelial cells under venous flow conditions. Moreover, platelets and neutrophils from Pyk2-knockout mice showed defective ability to form heterogeneous aggregates upon stimulation, while platelet monocyte interaction occurred normally. Consequently, platelet neutrophil aggregates, abundant in blood of wild-type mice upon inferior vena cava ligation, were virtually undetectable in Pyk2-knockout mice. Finally, we found that expression of Pyk2 was required for NETosis induced by activated platelets. Altogether our results demonstrate a critical role of Pyk2 in the regulation of the coordinated thromboinflammatory responses of endothelial cells, leukocytes and platelets leading to venous thrombosis. Pyk2 may represent a novel promising target in the treatment of deep vein thrombosis.  相似文献   
66.
RAD51 is an ATP-dependent recombinase, recruited by BRCA2 to mediate DNA double-strand breaks repair through homologous recombination and represents an attractive cancer drug target. Herein, we applied for the first-time protein-templated dynamic combinatorial chemistry on RAD51 as a hit identification strategy. Upon design of N-acylhydrazone-based dynamic combinatorial libraries, RAD51 showed a clear templating effect, amplifying 19 N-acylhydrazones. Screening against the RAD51–BRCA2 protein–protein interaction via ELISA assay afforded 10 inhibitors in the micromolar range. Further 19F NMR experiments revealed that 7 could bind RAD51 and be displaced by BRC4, suggesting an interaction in the same binding pocket of BRCA2. These results proved not only that ptDCC could be successfully applied on full-length oligomeric RAD51, but also that it could address the need of alternative strategies toward the identification of small-molecule PPI inhibitors.  相似文献   
67.
Long considered merely a trophic and mechanical support to neurons, astrocytes have progressively taken the center stage as their ability to react to acute and chronic neurodegenerative situations became increasingly clear. Reactive astrogliosis starts when trigger molecules produced at the injury site drive astrocytes to leave their quiescent state and become activated. Distinctive morphological and biochemical features characterize this process (cell hypertrophy, upregulation of intermediate filaments, and increased cell proliferation). Moreover, reactive astrocytes migrate towards the injured area to constitute the glial scar, and release factors mediating the tissue inflammatory response and remodeling after lesion. A novel view of astrogliosis derives from the finding that subsets of reactive astrocytes can recapitulate stem cell/progenitor features after damage, fostering the concept of astroglia as a promising target for reparative therapies. But which biochemical/signaling pathways modulate astrogliosis with respect to both the time after injury and the type of damage? Are reactive astrocytes overall beneficial or detrimental for neuroprotection and tissue regeneration? This debate has been animating this research field for several years now, and an integrated view on the results obtained and the possible future perspectives is needed. With this Commentary article we have attempted to answer the above-mentioned questions by reviewing the current knowledge on the molecular mechanisms controlling and sustaining the reaction of astroglia to injury and its stem cell-like properties. Moreover, the cellular/molecular mechanisms supporting the detrimental or beneficial features of astrogliosis have been scrutinized to gain insights on possible pharmacological approaches to enhance astrocyte neuroprotective activities.  相似文献   
68.
Aging and corrosion of reinforced concrete structures (RCS) is becoming a global problem, thus proper procedures for simulating the structural performance of corroded RCS should be assessed. Among the main corrosion effects, concrete cover cracking and reinforcement cross-section reduction may influence the materials’ constitutive laws, moreover the confinement contribution and the lateral instability of the longitudinal rebars can be modified. In the present paper, the predictive models available in the scientific literature to assess the materials’ mechanical properties of corroded RCS are recalled and employed into a novel model to derive the theoretical moment–curvature relationships for the cross-section of square and rectangular corroded reinforced concrete elements. The model accounts for cover spalling, buckling of longitudinal reinforcing bars, reduction in confinement pressures, reduction in concrete constitutive law due to the concrete cracking induced by rust formation and decay of mechanical properties for corroded reinforcements. The obtained results are compared with the classical simplified models for corroded RCS, highlighting that buckling and confinement variations cannot be disregarded into a reliable modelling strategy, especially when local ductility plays a key role in the performed investigations.  相似文献   
69.
The main aim of this study was to describe the clinical and immunological outcomes, as well as the inflammatory profile, of patients with advanced HIV in an assisted-living facility in which an outbreak of SARS-CoV-2 occurred. SARS-CoV-2 humoral and specific T-cell response were analyzed in patients with HIV infection and COVID-19; as a secondary objective of the analysis, levels of the inflammatory markers (IL-1β, IL-6, IL-8, and TNFα) were tested in the HIV/COVID-19 group, in HIV-positive patients without COVID-19, and in HIV-negative patients with mild/moderate COVID-19. Antibody kinetics and ability to neutralize SARS-CoV-2 were evaluated by ELISA assay, as well as the inflammatory cytokines; SARS-CoV-2 specific T-cell response was quantified by ELISpot assay. Mann–Whitney or Kruskal–Wallis tests were used for comparisons. Thirty patients were included with the following demographics: age, 57 years old (IQR, 53–62); 76% male; median HIV duration of infection, 18 years (15–29); nadir of CD4, 57/mmc (23–100) current CD4 count, 348/mmc (186–565). Furthermore, 83% had at least one comorbidity. The severity of COVID-19 was mild/moderate, and the overall mortality rate was 10% (3/30). Additionally, 90% of patients showed positive antibody titers and neutralizing activity, with a 100% positive SARS-CoV-2 specific T-cell response over time, suggesting the ability to induce an effective specific immunity. Significantly higher levels of IL-6, IL-8, and TNF-α in COVID-19 without HIV vs. HIV/COVID-19 patients (p < 0.05) were observed. HIV infection did not seem to negatively impact COVID-19-related inflammatory state and immunity. Further data are mandatory to evaluate the persistence of these immunity and its ability to expand after exposure and/or vaccination.  相似文献   
70.
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