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91.
Untrapping the metaphor of AIDS 总被引:1,自引:0,他引:1
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In order to determine prognostic factors in noncardiac medical patients treated by mechanical ventilation in a Veterans Administration hospital, 78 patient records were reviewed. Disease severity was scored by the Acute Physiology and Chronic Health Evaluation (APACHE) II system. Physicians' prior impressions of prognostic factors were compared with the actual results of this study. Most patients were middle-aged men with respiratory diseases. Fifty-nine patients (76 percent) died in the hospital. Survivors of hospitalization and nonsurvivors had similar age, diagnoses, emergency intubations, duration of ventilation, and pH and oxygen tension after 24 hours of ventilation. However, only one of 31 patients with a serum albumin level of 2.5 g/dl or less at the initiation of mechanical ventilation survived (p less than 0.001). Of 24 patients requiring a fractional inspired oxygen concentration greater than 50 percent at 24 hours, none survived (p less than 0.005). At all APACHE II scores, the mortality rates documented in this study were higher than predicted. Physicians overestimated the impact of several variables, including age and presence of pneumonia, on mortality. At the San Francisco Veterans Administration Medical Center, a low serum albumin level may aid in the decision whether to begin mechanical ventilation, and a high fractional inspired oxygen concentration at 24 hours may aid in the decision regarding further aggressive care. These findings need to be validated in other patients before being applied. Conversely, certain older patients, and those undergoing emergency intubation or intubation for a prolonged time, may have as good a prognosis as patients without these factors. 相似文献
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HUBERT COCHET M.D. YUKI KOMATSU M.D. FREDERIC SACHER M.D. AMIR SHERWAN JADIDI M.D. DANIEL SCHERR M.D. MATTHIEU RIFFAUD M.D. NICOLAS DERVAL M.D. ASHOK SHAH M.D. LAURENT ROTEN M.D PATRIZIO PASCALE M.D. JATIN RELAN Ph.D. MAXIME SERMESANT Ph.D. NICHOLAS AYACHE Ph.D. MICHEL MONTAUDON M.D. Ph.D. FRANÇOIS LAURENT M.D. MÉLÈZE HOCINI M.D. MICHEL HAÏSSAGUERRE M.D. PIERRE JAÏS M.D. Ph.D . 《Journal of cardiovascular electrophysiology》2013,24(4):419-426
MDCT/MRI Fusion for the Guidance of VT Ablation . Background: Delayed enhancement (DE) MRI can assess the fibrotic substrate of scar‐related VT. MDCT has the advantage of inframillimetric spatial resolution and better 3D reconstructions. We sought to evaluate the feasibility and usefulness of integrating merged MDCT/MRI data in 3D‐mapping systems for structure–function assessment and multimodal guidance of VT mapping and ablation. Methods: Nine patients, including 3 ischemic cardiomyopathy (ICM), 3 nonischemic cardiomyopathy (NICM), 2 myocarditis, and 1 redo procedure for idiopathic VT, underwent MRI and MDCT before VT ablation. Merged MRI/MDCT data were integrated in 3D‐mapping systems and registered to high‐density endocardial and epicardial maps. Low‐voltage areas (<1.5 mV) and local abnormal ventricular activities (LAVA) during sinus rhythm were correlated to DE at MRI, and wall‐thinning (WT) at MDCT. Results: Endocardium and epicardium were mapped with 391 ± 388 and 1098 ± 734 points per map, respectively. Registration of MDCT allowed visualization of coronary arteries during epicardial mapping/ablation. In the idiopathic patient, integration of MRI data identified previously ablated regions. In ICM patients, both DE at MRI and WT at MDCT matched areas of low voltage (overlap 94 ± 6% and 79 ± 5%, respectively). In NICM patients, wall‐thinning areas matched areas of low voltage (overlap 63 ± 21%). In patients with myocarditis, subepicardial DE matched areas of epicardial low voltage (overlap 92 ± 12%). A total number of 266 LAVA sites were found in 7/9 patients. All LAVA sites were associated to structural substrate at imaging (90% inside, 100% within 18 mm). Conclusion: The integration of merged MDCT and DEMRI data is feasible and allows combining substrate assessment with high‐spatial resolution to better define structure–function relationship in scar‐related VT. (J Cardiovasc Electrophysiol, Vol. 24, pp. 419‐426, April 2013) 相似文献
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A. D. Karatzanis E. Koudounarakis I. Papadakis G. Velegrakis 《European archives of oto-rhino-laryngology》2012,269(3):731-737
Metastasis to regional lymph nodes constitutes the main route toward progression and dissemination of head and neck carcinoma;
at the same time it is the most significant adverse prognostic indicator for this disease. In recent years, significant focus
has been given on the molecular mechanisms behind lymph node metastasis of head and neck cancer. The aim of this study is
to assess the role of growth factor expression and function in association with lymph node metastasis and overall prognosis
of head and neck cancer. Current literature, searching for experimental data regarding the molecular pathways of lymph node
dissemination of head and neck cancer, is reviewed giving special emphasis on the expression and prognostic significance of
specific growth factors. Members of the vascular endothelial growth factor (VEGF), mostly VEGF-C and VEGF-D, with their action
through the receptors VEGFR-3 and VEGFR-2, constitute the most extensively studied growth factors associated with lymphangiogenesis
so far. High expression of these as well as other molecules, including angiopoietins, insulin-like growth factor, and fibroblast
growth factor, has been associated with lymph node metastasis and poor prognosis in head and neck squamous cell carcinoma.
Numerous growth factors seem to play an important role regarding the lymph node metastatic potential of head and neck cancer.
Further research is necessary in order to further clarify the molecular pathways and introduce novel therapeutic options. 相似文献
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Barbara Uhl Katharina T Prochazka Karoline Fechter Katrin Pansy Hildegard T Greinix Peter Neumeister Alexander JA Deutsch 《World journal of gastrointestinal oncology》2022,14(1):153-162
Approximately 8% of all non-Hodgkin lymphomas are extranodal marginal zone B cell lymphomas of mucosa-associated lymphoid tissue (MALT), also known as MALT lymphomas. These arise at a wide range of different extranodal sites, with most cases affecting the stomach, the lung, the ocular adnexa and the thyroid. The small intestine is involved in a lower percentage of cases. Lymphoma growth in the early stages is associated with long-lasting chronic inflammation provoked by bacterial infections (e.g., Helicobacter pylori or Chlamydia psittaci infections) or autoimmune conditions (e.g., Sjögren’s syndrome or Hashimoto thyroiditis). While these inflammatory processes trigger lymphoma cell proliferation and/or survival, they also shape the microenvironment. Thus, activated immune cells are actively recruited to the lymphoma, resulting in either direct lymphoma cell stimulation via surface receptor interactions and/or indirect lymphoma cell stimulation via secretion of soluble factors like cytokines. In addition, chronic inflammatory conditions cause the acquisition of genetic alterations resulting in autonomous lymphoma cell growth. Recently, novel agents targeting the microenvironment have been developed and clinically tested in MALT lymphomas as well as other lymphoid malignancies. In this review, we aim to describe the composition of the microenvironment of MALT lymphoma, the interaction of activated immune cells with lymphoma cells and novel therapeutic approaches in MALT lymphomas using immunomodulatory and/or microenvironment-targeting agents. 相似文献
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