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991.
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IntroductionAlthough volume–outcome relationships in transplantation have been well-defined, the effects of large changes in center volume are less well understood. The purpose of the current study was to examine the impact of changes in center volume on outcomes after heart transplantation.MethodsRetrospective analysis was performed of adult patients undergoing heart transplant between 2000 and 2017 identified in the United Network for Organ Sharing database. Exclusions included annual volume <10. Patients were grouped according to percentage change in center volume from the previous year. Multivariable Cox regression models were adjusted for the significant preoperative variance identified on univariate analyses.ResultsOf the 29,851 transplants during the study period, 64% were at centers with stable volume (±25% annual change), whereas 10% were performed at contracting (−25% change or more) and 26% were performed at growing (+25% change or more) centers. Average volume was lower with contracting centers compared with stable or growing programs (21 vs 36, P< .001). Thirty-day mortality was greater in decreasing centers (6% vs 4%, P < .001), with more acute rejection treatments at 1y (27% vs 24% P < .001). The adjusted risk of mortality among contracting centers was 1.25 ([1.07–1.46], P= .004), whereas growing centers had unaffected risk (0.90 [0.79–1.02], P= .103). Causes of death were similar between groups.ConclusionsRapid growth of transplant center volume has occurred at select centers in the United States without decrement in programmatic outcomes. Decreasing center volume has been associated with poorer outcomes, although the causative nature of this relationship requires further investigation.  相似文献   
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IntroductionThe EEG, alongside clinical examination, imaging studies, and SSEPs, is used to determine the prognosis following hypoxic encephalopathy postcardiac arrest. Generalized periodic epileptiform discharges (GPEDs) are recognized as a “malignant” EEG pattern associated with very poor outcome with previous studies reporting no or few survivors. We looked at our database of cardiac arrest patients who subsequently developed GPEDs to determine clinical outcome and profile any survivors.MethodologyWe identified all cardiac arrest patients treated at King's College Hospital between 2011–2014 who developed hypoxic encephalopathy associated with GPEDs, BiPLEDs (bilateral periodic lateralized epileptiform discharges), and periodic discharges on first EEG. We collected clinical data including age, gender, downtime, EEG reactivity, presence of seizures or myoclonus, and outcome. Survivors were defined as patients who were discharged from the hospital to home or a neurorehabilitation unit.ResultsThirty-six postcardiac arrest patients with hypoxic encephalopathy were identified, 24/36 with GPEDs, and 12/36 with BiPLEDs on first EEG. The mean age of patients was 62.8 ± 14.5 years old, with 27 males (75%) and 9 females (25%). Ten of thirty-six patients survived, which is slightly higher than previously reported. Statistical tests to compare clinical characteristics between survivors and nonsurvivors demonstrated no significant differences except for trend to significance for the presence of reactivity on first EEG (p = 0.0794). On discharge, one survivor had good functional outcome (and subsequently became independent), but all others were dependent for all ADLs (activities of daily living).ConclusionGeneralized periodic epileptiform discharges carry a grave clinical prognosis following cardiac arrest. This study did identify a higher number of survivors compared to previous studies, but most were severely disabled at hospital discharge. Reactivity of the first EEG might predict better prognosis and merit further evaluation.This article is part of a Special Issue entitled “Status Epilepticus”.  相似文献   
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ObjectiveThe use of mechanical circulatory support (MCS) in lung transplantation has been steadily increasing over the prior decade, with evolving strategies for incorporating support in the preoperative, intraoperative, and postoperative settings. There is significant practice variability in the use of these techniques, however, and relatively limited data to help establish institutional protocols. The objective of the AATS Clinical Practice Standards Committee (CPSC) expert panel was to review the existing literature and establish recommendations about the use of MCS before, during, and after lung transplantation.MethodsThe AATS CPSC assembled an expert panel of 16 lung transplantation physicians who developed a consensus document of recommendations. The panel was broken into subgroups focused on preoperative, intraoperative, and postoperative support, and each subgroup performed a focused literature review. These subgroups formulated recommendation statements for each subtopic, which were evaluated by the entire group. The statements were then developed via discussion among the panel and refined until consensus was achieved on each statement.ResultsThe expert panel achieved consensus on 36 recommendations for how and when to use MCS in lung transplantation. These recommendations included the use of veno-venous extracorporeal membrane oxygenation (ECMO) as a bridging strategy in the preoperative setting, a preference for central veno-arterial ECMO over traditional cardiopulmonary bypass during the transplantation procedure, and the benefit of supporting selected patients with MCS postoperatively.ConclusionsAchieving optimal results in lung transplantation requires the use of a wide range of strategies. MCS provides an important mechanism for helping these critically ill patients through the peritransplantation period. Despite the complex nature of the decision making process in the treatment of these patients, the expert panel was able to achieve consensus on 36 recommendations. These recommendations should provide guidance for professionals involved in the care of end-stage lung disease patients considered for transplantation.  相似文献   
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Background

Glutamate plays a key role for post-ischaemic recovery of myocardial metabolism. According to post hoc analyses of the two GLUTAMICS trials, patients without diabetes benefit from glutamate with less myocardial dysfunction after coronary artery bypass surgery (CABG). Copeptin reflects activation of the Arginine Vasopressin system and is a reliable marker of heart failure but available studies in cardiac surgery are limited. We investigated whether glutamate infusion is associated with reduced postoperative rises of plasma Copeptin (p-Copeptin) after CABG.

Methods

A prespecified randomised double-blind substudy of GLUTAMICS II. Patients had left ventricular ejection fraction ≤0.30 or EuroSCORE II ≥3.0 and underwent CABG ± valve procedure. Intravenous infusion of 0.125 M L-glutamic acid or saline at 1.65 mL/kg/h was commenced 10–20 min before the release of the aortic cross-clamp and then continued for another 150 min P-Copeptin was measured preoperatively and postoperatively on day one (POD1) and day three. The primary endpoint was an increase in p-Copeptin from the preoperative level to POD1. Postoperative stroke ≤24 h and mortality ≤30 days were safety outcomes.

Results

We included 181 patients of whom 48% had diabetes. The incidence of postoperative mortality ≤30 days (0% vs. 2.1%; p = .50) and stroke ≤24 h (0% vs. 3.2%; p = .25) did not differ between the glutamate group and controls. P-Copeptin increased postoperatively with the highest values recorded on POD1 without significant inter-group differences. Among patients without diabetes, p-Copeptin did not differ preoperatively but postoperative rise from preoperative level to POD1 was significantly reduced in the glutamate group (73 ± 66 vs. 115 ± 102 pmol/L; p = .02). P-Copeptin was significantly lower in the Glutamate group on POD1 (p = .02) and POD 3 (p = .02).

Conclusions

Glutamate did not reduce rises of p-Copeptin significantly after moderate to high-risk CABG. However, glutamate was associated with reduced rises of p-Copeptin among patients without diabetes. These results agree with previous observations suggesting that glutamate mitigates myocardial dysfunction after CABG in patients without diabetes. Given the exploratory nature of these findings, they need to be confirmed in future studies.  相似文献   
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