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41.
Teixeira R Monteiro P Marques G Pego JM Louren?o M Tavares C Reboredo A Monteiro S Gon?alves F Ferreira MJ Freitas M Ribeiro G Providência LA 《Revista portuguesa de cardiologia》2012,31(9):545-554
IntroductionInhibition of platelet aggregation appears two hours after the first dose of clopidogrel, becomes significant after the second dose, and progresses to a steady-state value of 55% by day seven. Low response to clopidogrel has been associated with increased risk of stent thrombosis and ischemic events, particularly in the context of stable heart disease treated by percutaneous coronary intervention.ObjectiveTo stratify medium-term prognosis of an acute coronary syndrome (ACS) population by platelet aggregation.MethodsWe performed a prospective longitudinal study of 70 patients admitted for an ACS between May and August 2009. Platelet function was assessed by ADP-induced platelet aggregation using a commercially available kit (Multiplate® analyzer) at discharge. The primary endpoint was a combined outcome of mortality, non-fatal myocardial infarction, or unstable angina, with a median follow-up of 136.0 (79.0–188.0) days.ResultsThe median value of platelet aggregation was 16.0 U (11.0–22.5 U) with a maximum of 41.0 U and a minimum of 4.0 U (normal value according to the manufacturer: 53–122 U). After ROC curve analysis with respect to the combined endpoint (AUC 0.72), we concluded that a value of 18.5 U conferred a sensitivity of 75.0% and a specificity of 68% to that result. We therefore created two groups based on that level: group A – platelet aggregation <18.5 U, n = 44; and group B – platelet aggregation ≥18.5 U, n = 26. The groups were similar with respect to demographic data (age 60.5 [49.0–65.0] vs. 62.0 [49.0–65.0] years, p = 0.21), previous cardiovascular history, and admission diagnosis. There were no associations between left ventricular ejection fraction, GRACE risk score, or length of hospital stay and platelet aggregation. The groups were also similar with respect to antiplatelet, anticoagulant, proton pump inhibitor (63.6 vs. 46.2%, p = 0.15) and statin therapy. The variability in platelets and hemoglobin was also similar between groups. Combined event-free survival was higher in group A (96.0 vs. 76.7%, log-rank p < 0.01). Platelet aggregation higher than 18.5 U was an independent predictor of the combined event (HR 6.75, 95% CI 1.38–32.90, p = 0.02).ConclusionIn our ACS population platelet aggregation at discharge was a predictor of medium-term prognosis. 相似文献
42.
Gomes V Brand?o V Mimoso J Gago P Trigo J Santos W Marques N Candeias R Pereira S Marques V Camacho A de Jesus I 《Revista portuguesa de cardiologia》2012,31(3):193-201
ObjectiveTo analyze the impact of reperfusion by either primary percutaneous coronary intervention (PPCI) or fibrinolysis, and mortality rates of a pre-hospital fast-track network for treating patients with ST-elevation myocardial infarction (STEMI).Methods and ResultsA pre-hospital network for STEMI patients, designated the Green Lane for Acute Myocardial Infarction (GL-AMI), has been implemented in the southern region of Portugal – the Algarve Project. We performed an observational study based on a prospective registry of 1338 patients admitted to Faro Hospital between 2004 and 2009, classified in two groups according to the method of admission: emergency department group (EDG) and GL-AMI group (GLG). More patients from GLG were reperfused (p < 0.0001). PPCI was the preferred method of reperfusion, 73.1% in GLG and 45.3% in EDG. Time delays were significantly shorter in GLG, except for pre-hospital delay: pre-hospital delay (p = 0.11); door-to-needle (p < 0.0001); door-to-balloon (p < 0.0001); and delay between symptoms and reperfusion (p < 0.0001). In-hospital mortality (4.3% vs 9.2%, p = 0.0007) and 6-month mortality (6.3% vs 13.8%, p < 0.0001) were significantly lower in GLG.ConclusionsThe Algarve Project significantly reduced the time delay between onset of symptoms and reperfusion, significantly increased the rate of reperfusion, and significantly reduced in-hospital and six-month mortality. 相似文献
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Teleman AA Ratzenb?ck I Oldham S 《Experimental and clinical endocrinology & diabetes》2012,120(4):184-185
The molecular mechanisms underlying development of obesity and diabetic complications are not well understood. Drosophila has become a popular model organism for studying a variety of human diseases. We discuss here emerging Drosophila models of obesity and diabetic complications. 相似文献
46.
Although Ren-2 transgenic rat (TGR) is defined as a model of angiotensin II-dependent hypertension, we studied whether the renin-angiotensin system (RAS) is really the main contributor to blood pressure (BP) elevation in hetero- and homozygous TGRs. Moreover, we examined whether repeated antisense (AS) therapy against AT(1) receptors would have a similar effect on the BP and the contribution of the principle vasoconstrictor/vasodilator systems to BP regulation in young and adult TGRs. From the age of 30 (young) and 100 (adult) days, rats were injected with AS for 40 days in 10-day intervals. After 10 and 40 days of AS therapy, the basal BP and acute BP responses to the sequential blockade of the RAS, sympathetic nervous (SNS) and nitric oxide systems were determined in conscious rats. The RAS system was the major system maintaining elevated BP in young homozygous animals, whereas there was an increasing contribution of the SNS in heterozygous TGR with age. The AS therapy in the young TGR had a transient BP-lowering effect that was associated with reduced cardiac hypertrophy; the AS therapy was most effective in young homozygous TGR, causing a substantial reduction of angiotensin-dependent vasoconstriction. In heterozygous rats, AS therapy at earlier stages was related to an inhibition of sympathetic vasoconstriction, whereas to RAS inhibition in established hypertension. In conclusion, repeated AS therapy had transient antihypertensive effects exclusively in young TGR. The contribution of the RAS to BP maintenance is highly important only in homozygous TGRs, whereas it is surpassed by SNS in heterozygous TGR. 相似文献
47.
Bulur S ?nder HI Aslantas Y Ekinozu I Kili? A? Yalcin S Bulur ? Ozhan H 《Blood coagulation & fibrinolysis》2012,23(5):367-369
Mean platelet volume (MPV) has been recognized as an independent risk factor of hypertension. Hypertensive end-organ damage worsens the prognosis in hypertensive patients. We aimed to investigate the relationship between MPV levels and subclinical end-organ damage in hypertensive patients. One hundred and sixteen hypertensive patients (81 women, 35 men, with a mean age of 53 ± 11) were included in the study. There was no correlation between MPV and left-ventricular mass index (LVMI) (r = 0.145; P = 0.14) or albuminuria (r = 0.009; P = 0.93). Among the individuals that had grade I and grade II retinopathy, MPV levels (8.3 ± 2 fL, 8.2 ± 1.3 fL; P = 0.28) were similar either. We concluded that there was no correlation between MPV and markers of end-organ damage in hypertensive patients. 相似文献
48.
Z?bczyk M Butenas S Plicner D Fijorek K Sadowski J Undas A 《Blood coagulation & fibrinolysis》2012,23(3):189-194
Circulating active tissue factor (TF) and activated factor XI (FXIa) have been detected in subgroups of acute coronary syndromes (ACSs) and stable angina patients. We sought to evaluate the determinants of active TF and FXIa in stable angina patients. We studied 124 consecutive stable angina patients. Recent ACS, atrial fibrillation, and anticoagulant therapy were the exclusion criteria. Plasma active TF and FXIa were determined by measuring the response to inhibitory antibodies. T helper 1 lymphocyte (Th1) and Th2 responses were assessed in plasma by interleukin (IL)-4, IL-6, IL-8, IL-10, IL-18, interferon-γ, and tumor necrosis factor-α, oxidative stress by 8-isoprostaglandin F(2α) (8-iso-PGF(2α)), and coagulation by prothrombin fragments F1+2 (F1+2) and free TF pathway inhibitor (f-TFPI). TF and FXIa activity were detected in 25 (20.2%) and 49 (39.5%) stable angina patients, respectively. Both factors were found in 23 (18.5%) patients. Patients with detectable TF or FXIa had higher F1+2, 8-iso-PGF(2α), IL-6, but not other cytokines, and lower f-TFPI (all P < 0.001) compared with the remainder. There were no intergroup differences with regard to cardiovascular risk factors or medication. Multivariate analysis showed that F1+2 and f-TFPI were the only independent predictors of the TF presence, whereas 8-iso-PGF(2α) and F1+2 predicted the presence of FXIa in stable angina patients. In stable angina patients, circulating active TF and FXIa are associated with enhanced thrombin formation, with a minor effect of inflammatory mediators. Moreover, FXIa is also related to oxidative stress, indicating additional links between coagulation and free radical generation in stable angina. 相似文献
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