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101.
OBJECTIVES: To identify an accurate and reproducible method to define myocardial infarct (MI) size, we conducted a study in a closed-chest canine model of acute myocardial infarction, in which MI size was measured using different thresholding techniques and by imaging at different delay times after contrast administration. BACKGROUND: The MI size by contrast-enhanced magnetic resonance imaging (CE-MRI) is directly related to long-term prognosis. However, previous measurements were done using nonuniform methods and tended to overestimate nonviable areas. METHODS: Thirteen animals underwent 90 min of coronary artery occlusion, followed by reperfusion. The CE-MRI data were acquired within 24 h after reperfusion and compared with triphenyltetrazolium chloride pathology. In the first nine animals, images were obtained approximately 15 min after gadolinium diethylene triamine penta-acetic acid (Gd-DTPA) using an inversion-recovery gradient-echo pulse sequence. To identify the most accurate method, MI size by CE-MRI was measured visually and by semi-automatic thresholding techniques, using different criteria. In four additional animals, images were acquired every 6 min until 30 min after Gd-DTPA. RESULTS: Postmortem MI size was 13.5 +/- 2.6% of left ventricular volume. Semi-automatic techniques, using full-width at half-maximum (FWHM) criterion, correlated best with postmortem data (r(2) = 0.94, p < 0.001; results confirmed by Bland-Altman plots). Using FWHM, there was no difference in MI size between different delay times after contrast (15.2 +/- 2.9% to 14.5 +/- 4.2% at 6 and 30 min, respectively; p = NS). CONCLUSIONS: When an objective technique is used to define MI size by CE-MRI, accurate infarct size measurements can be obtained from images obtained up to 30 min after contrast administration.  相似文献   
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Intracranial haemorrhages are rare but potentially life-threatening complications of spine surgery. Most reported cases involved subdural or cerebellar haemorrhages; supratentorial parenchymal bleeding is very uncommon. We report a 28-year-old woman who underwent resection of a thoracic Ewing''s sarcoma, and developed fatal haemorrhages around her cerebral metastases during surgery. The clinical presentations, possible pathogenesis and potential preventive measures are discussed. Patients with disseminated metastases within the neural axis are at risks of intracranial complications during spine surgery. The presence of intracranial mass lesions should be considered as a relative contraindication to intradural spine surgery.  相似文献   
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Background:Good communication strategies are essential in times of crisis, such as the coronavirus pandemic. The dissemination of inaccurate information and the need for social isolation to control coronavirus disease 2019 (COVID-19) have shown a negative impact on the population, causing damage to mental health, with the appearance or worsening of symptoms of stress, fear, anxiety, and depression. Thus, the systematic review study is intended to gather evidence on the impact of information about COVID-19 on the mental health of the population.Methods:This systematic review protocol is conducted using the guidelines of the preferred reporting items for systematic reviews and meta-analyses protocols and the Cochrane Handbook for Systematic Reviews of Interventions. The review aims to include published studies that address the exposure of the general population to information about COVID-19, through observational and experimental studies, which consider the following outcomes: fear, stress, anxiety, and depression. Thus, a comprehensive research strategy will be conducted in the following databases: PubMed / Medline, Scopus, Web of Science, EMBASE, Science Direct, CINAHL, PsycINFO and Cochrane Central Register of Controlled Trials (CENTRAL). Two independent reviewers will perform all procedures, such as study selection, data collection, and methodological evaluation. Disagreements will be forwarded to a third reviewer. RevMan 5.3 software will be used for data analysis.Results:This systematic review will provide evidence of the influence of access to and consumption of media and scientific information about COVID-19 on the mental health of the population. It will consider information about the characterization of the study and the population studied, clinical and epidemiological information on mental health, and data on access to and consumption of media and scientific information.Discussion:The results should inform about the consequences of communication about the new coronavirus on the emergence or worsening of psychological and psychiatric symptoms, allowing to develop strategies to achieve effective communication of information to promote the mental health of the population.Systematic review registration number:PROSPERO CRD42020182918  相似文献   
105.
BackgroundPatients with acute myocardial infarction may have a large infarcted area and ventricular dysfunction despite early thrombolysis and revascularization.ObjectiveTo investigate the behavior of circulating cytokines in patients with ST-segment elevation myocardial infarction (STEMI) and their relationship with ventricular function.MethodsIn the BATTLE-AMI (B and T Types of Lymphocytes Evaluation in Acute Myocardial Infarction) trial, patients with STEMI were treated with a pharmacoinvasive strategy. The plasma levels of cytokines (IL-1 β , IL-4, IL-6, IL-10, and IL-18) were tested using enzyme-linked immunosorbent assay (ELISA) at baseline and after 30 days. Infarcted mass and left ventricular ejection fraction (LVEF) were examined by 3-T cardiac magnetic resonance imaging. All p-values < 0.05 were considered statistically significant.ResultsCompared to baseline, lower levels were detected for IL-1 β (p = 0.028) and IL-18 (p < 0.0001) 30 days after STEMI, whereas higher levels were observed for IL-4 (p = 0.001) and IL-10 (p < 0.0001) at that time point. Conversely, no changes were detected for IL-6 levels (p = 0.63). The levels of high-sensitivity C-reactive protein and IL-6 correlated at baseline (rho = 0.45, p < 0.0001) and 30 days after STEMI (rho = 0.29, p = 0.009). At baseline, correlation between IL-6 levels and LVEF was also observed (rho = -0.50, p = 0.004).ConclusionsDuring the first month post-MI, we observed a marked improvement in the balance of pro- and anti-inflammatory cytokines, except for IL-6. These findings suggest residual inflammatory risk. (Arq Bras Cardiol. 2020; [online].ahead print, PP.0-0)  相似文献   
106.
PurposeThis systematic review aimed to investigate the prevalence of odontogenic cysts and tumors associated with impacted third molars (ITM).MethodsOnly studies that performed histopathological diagnosis of lesions were eligible for inclusion. Five main electronic and three grey literature databases were searched. Risk of bias (RoB) of included articles was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data.ResultsFrom 1,300 studies identified, 16 met the inclusion criteria. Seven studies were classified as high, seven as moderate, and two as low RoB. The prevalence of odontogenic cysts and tumors associated with ITM was 5.3% (95%CI: 3.1%–8.1%) of ITM. Odontogenic cysts in particular were found in 4.4% (95%CI: 2.5–6.8%) of the extracted ITM, whilst odontogenic tumors in 0.5% (95%CI: 0.2–0.9%). The dentigerous cyst was mentioned in eleven studies with a pooled prevalence of 2.1% (95%CI: 1.4–3.1%). The odontogenic keratocyst was cited by nine studies and had a prevalence of 0.5% (95%CI: 0.2–0.7%). The radicular cyst was mentioned only in three articles and the pooled prevalence was 4.7% (95%CI: 0.0–19.4%)ConclusionOdontogenic cysts and tumors were found in 5.3% of ITM extracted. The most common lesions were the radicular cyst, dentigerous cyst, and odontogenic keratocyst.  相似文献   
107.
Pharmaceutical Chemistry Journal - Azines or di-imines are compounds containing R1R2C=N-N=CR3R4 fragment in its structure. These compounds have received special attention due to their importance as...  相似文献   
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109.
Clinical Rheumatology - Systemic lupus erythematosus (SLE) is an autoimmune inflammatory disorder for which Major Histocompatibility Complex (MHC) genes are well-identified as risk factors. SLE...  相似文献   
110.
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