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The ability to decode letters into language sounds is essential for reading success, and accurate identification of children at high risk for decoding impairment is critical for reducing the frequency and severity of reading impairment. We examined the utility of behavioral (standardized tests), and functional and structural neuroimaging measures taken with children at the beginning of a school year for predicting their decoding ability at the end of that school year. Specific patterns of brain activation during phonological processing and morphology, as revealed by voxel-based morphometry (VBM) of gray and white matter densities, predicted later decoding ability. Further, a model combining behavioral and neuroimaging measures predicted decoding outcome significantly better than either behavioral or neuroimaging models alone. Results were validated using cross-validation methods. These findings suggest that neuroimaging methods may be useful in enhancing the early identification of children at risk for poor decoding and reading skills.  相似文献   
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Patients with schizophrenia are predisposed toward developing cardiovascular disease. Although neuroleptics affect the cardiovascular system, it is also important to consider the consequences of the disease itself such as lower physical activity due to living on disability pension, inadequate nutrition, and/or nicotine addiction, being more common among patients with schizophrenia versus the general population. All these factors combined lead to an increased risk of death caused by cardiovascular conditions in schizophrenic patients. Individuals receiving typical antipsychotic drugs have been reported to have elevated concentrations of antiphospholipid antibodies, including anticoagulants and anticardiolipin antibodies. The presence of both antibodies is associated with an increased risk for thromboembolism. It is also likely that mental illness is accompanied by increased procoagulant activity. Patients with acute psychosis have been shown to have a statistically significant increase in the concentrations of D-dimer, P-selectin, and in the expression of platelet glycoprotein IIb/IIIa receptors. Learning about causes and mechanisms of venous thromboembolism could help to reduce or neutralize the adverse effects of antipsychotic treatment and facilitate the identification of appropriate markers necessary to monitor changes and provide preventive care against hazardous and potentially fatal complications such as deep venous thrombosis and pulmonary embolism. Before atypical neuroleptic treatment is administered to hospitalized patients, all possible risk factors for thromboembolism should be considered to allow the application of lower risk drugs. Also, other preventive measures should be taken into account, including hydration, compression stockings, regular exercise of lower extremities, and low-molecular-weight heparin injections.  相似文献   
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The aim of the present study was to determine the impact of CYP2C19*17 on the pharmacokinetics and pharmacodynamics of the active metabolite of clopidogrel and the pharmacokinetics of proguanil. Thus, we conducted an open‐label two‐phase cross‐over study in 31 healthy male volunteers (11 CYP2C19*1/*1, 11 CYP2C19*1/*17 and nine CYP2C19*17/*17). In Phase A, the pharmacokinetics of the derivatized active metabolite of clopidogrel (CAMD) and platelet function were determined after administration of a single oral dose of 600 mg clopidogrel (Plavix; Sanofi‐Avensis, Horsholm, Denmark). In Phase B, the pharmacokinetics of proguanil and its metabolites cycloguanil and 4‐chlorphenylbiguanide (4‐CPB) were determined in 29 of 31 subjects after a single oral dose of 200 mg proguanil given as the combination drug Malarone (GlaxoSmithKline Pharma, Brondby, Denmark). Significant correlations were found between the area under the time–concentration curve (AUC0–∞) of CAMD and both the absolute ADP‐induced P2Y12 receptor‐activated platelet aggregation (r = ?0.60, P = 0.0007) and the percentage inhibition of aggregation (r = 0.59, P = 0.0009). In addition, the CYP2C19*17/*17 and CYP2C19*1/*17 genotype groups had significantly higher percentage inhibition of platelet aggregation compared with the CYP2C19*1/*1 subjects (geometric mean percentage inhibition of 84%, 73% and 63%, respectively; P = 0.014). Neither the absolute ADP‐induced P2Y12 receptor‐activated platelet aggregation, exposure to CAMD nor the pharmacokinetic parameters of proguanil, cycloguanil and 4‐CPB exhibited any significant differences among the genotype groups. In conclusion, carriers of CYP2C19*17 exhibit higher percentage inhibition of platelet aggregation, but do not have significantly lower absolute P2Y12 receptor‐activated platelet aggregation or higher exposure to the active metabolite after a single oral administration of 600 mg clopidogrel.  相似文献   
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In acute myocardial infarction, lidocaine is considered the drug of choice for the treatment of malignant ventricular arrhythmias. While initially a so-called "selective" treatment strategy prevailed, in which lidocaine was administered only after the onset of certain "warning arrhythmias," the prophylactic use of lidocaine in acute myocardial infarction has been gaining wider usage in intravenous and intramuscular application in recent years. Both therapeutic applications have been found to be problematic of late, which has led to increasingly restrictive use of lidocaine. While in selective treatment forms, the definition and prompt recognition of the so-called warning arrhythmias created especially acute problems, the prophylactic therapeutic use is problematic due to the occurrence of sometimes serious side effects, which is to be expected as the size of the collective being treated increases. Both treatment forms also appear limited by the narrow preventive efficacy of lidocaine against malignant ventricular arrhythmias, especially against ventricular fibrillation. The current therapeutic recommendation for lidocaine in acute myocardial infarction should be limited to patients presenting with very frequent and complex ventricular arrhythmias, especially when these are elicited by an R-on-T phenomenon. Side effects and other therapeutic problems encountered when the therapeutic modality is switched or adjusted can be greatly reduced by careful dosing and selection of the optimal combination substances.  相似文献   
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Mononuclear cells (MNCs) containing peripheral blood stem cells (PBSCs) were obtained from solid-tumor patients undergoing mobilizing chemotherapy followed by granulocyte colony-stimulating factor for PBSC transplantation-supported dose-intensified anticancer chemotherapy and were transplanted into unconditioned "nonleaky" young severe combined immunodeficient mice. Multilineage engraftment was shown by flow cytometry and immunocytochemistry using monoclonal antibodies to various human cell surface antigens as well as identification of human immunoglobulin in murine sera. Within a dose range of MNCs suitable for transplantation (10 to 36 x 10(6) cells/graft) the number of CD34+ cells injected (optimal at > 0.7 x 10(6)/graft) determined the yield of human cells produced in recipient animals. Engraftment of hu PBSC preparations resulted in prolonged generation of physiologic levels of human cytokines including interleukin-3 (IL-3), IL-6, and granulocyte- macrophage colony-stimulating factor, which were detectable in the murine blood over a period of at least 4 months. In vivo survival of immature human progenitor cells was preserved even 9 months after transplantation. Because human IL-3 is known to stimulate early hematopoiesis, a rat fibroblast cell line was stably transfected with a retroviral vector carrying the human IL-3 gene and cotransplanted subcutaneously as additional source of growth factor. Cotransplants of this cell line producing sustained in vivo levels of circulating human IL-3 for at least 12 weeks significantly accelerated the process of engraftment of huPBSC and spurred the spread of mature human cells to the murine spleen, liver, thymus, and peripheral blood. Cotransplants of allogeneic human bone marrow stromal cells derived from long-term cultures resulted in a comparable--though less prominent--support of engraftment.  相似文献   
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Summary A solid phase radioimmunoassay on microtiter plates was adapted for the estimation of mumps antibodies using commercially available complement-fixing mumps antigen. The sensitivity of the test is superior to that of hemagglutination inhibition and lies in the same range as the virus neutralization test performed on chick fibroblasts. The method is useful for screening large series of human sera, for instance in connection with vaccination programs.
Radioimmunologische Bestimmung der Mumps Immunität auf antigenbeschichteten Microtiterplatten
Zusammenfassung Eine radioimmunologische Bestimmung von Virusantikörpern mittels eines an Mikrotiterplatten fest gebundenen Antigens wurde entwickelt zur Bestimmung von Mumpsantikörpern. Als Antigen diente ein käufliches Komplementbindendes Mumps-Antigen. Die Methode ist empfindlicher als die Hämagglutinationshemmung; sie liegt im Bereich der Empfindlichkeit der Virusneutralisation auf Hühnerfibroblasten. Ihre Anwendung ist vor allem geeignet für große Serien von Antikörperbestimmungen in Humanseren, z. B. im Zusammenhang mit Impfprogrammen.
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Labels such as ‘Large’ or ‘Super‐size’ are often used to describe portion sizes. How do these normative labels influence consumer choice and how much they ultimately either consume or waste? Although one might believe that firms use normative labels to impact choice behavior through loss aversion, a field experiment shows consumer's willingness to pay is inconsistent with a loss aversion explanation. Although portions were clearly visible, individuals appeared to use the labels as objective information about their size. Importantly, a second study showed these labels also led people to eat less when food was given a larger sounding name than a smaller name (double vs. regular; regular vs. half‐size). If labels are used as size information, policies governing normative names could help reduce food consumption or reduce waste. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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