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1.

Introduction

Left ventricular (LV) dysfunction is estimated to occur in 10%–25% of the general intensive care unit (ICU) population and is frequently seen as regional wall motion abnormalities (RWMAs). Although RWMA is mostly attributed to myocardial ischemia or infarction, some studies have suggested that nonischemic RWMA might also be prevalent. We sought to establish that RWMA can be seen in critically ill patients with normal coronary arteries and to explore reasons for RWMA in this population.

Methods

In this retrospective study, data from the hospital angiography register and the ICU register were collated between 2012 and 2019. Patients were identified who underwent angiography in conjunction with their ICU stay and had RWMA on echocardiography. Patients were divided into either those with non-obstructed or those with obstructed coronary arteries. Cardiac magnetic resonance imaging (cMRI) examinations were reviewed if they had been performed on patients with non-obstructed coronaries.

Results

We identified 53 patients with RWMA and non-obstructed coronary arteries and 204 patients with RWMA and obstructed coronary arteries. Patients with non-obstructed coronary arteries were more often female, younger, and had fewer cardiovascular risk factors. They less commonly had ST elevation, but more frequently had T-wave inversion or serious arrhythmias. Troponin levels were higher in patients with obstructed coronary arteries, but NT-proBNP was similar between the groups. There were no differences in risk-adjusted 90-day mortality between patients with non-obstructed versus obstructed coronary arteries (OR 1.21, [95% CI 0.56–2.64], p = .628). In those with non-obstructed coronary arteries, follow-up echocardiography was available for 38 patients, of whom 30 showed normalization of cardiac function. Of the 14 patients with non-obstructed coronary arteries on whom cMRI was performed, 7 had a tentative diagnosis of Takotsubo syndrome or myocardial stunning; 4 had a myocardial infarction (preexisting in 3 cases); 1 patient had acute myocarditis; 1 patient had post-myocarditis; and 1 patient was diagnosed with dilated cardiomyopathy.

Conclusion

RWMA can be seen to occur in critically ill patients in the absence of coronary artery obstruction. Several conditions can cause regional hypokinesia, and cMRI is useful to evaluate the underlying etiology.  相似文献   
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Objective To evaluate various treatment strategies in critically ill patients with ischaemic acute renal failure, there is a need for reliable bedside measurements of total renal blood flow (RBF), glomerular filtration rate (GFR) and renal oxygen consumption without the need for urine collection.Design The continuous renal vein thermodilution method and the infusion clearance techniques were validated against the gold standard technique, the urinary clearance of paraaminohippurate (PAH) and chromium ethylenediaminetetraacetic acid, respectively.Setting University hospital cardiothoracic ICU.Patients Seventeen uncomplicated mechanically ventilated post-cardiac surgical patients.Interventions None.Measurements and results Renal blood flow, GFR and the renal filtration fraction (FF) were measured for two consecutive 30-min periods by urinary clearance and compared with simultaneous measurements made by the thermodilution and infusion clearance techniques. Urinary clearance for PAH was corrected for by renal extraction of PAH. The within-group error, repeatability coefficient and the coefficient of variation were highest for the thermodilution technique and lowest for the infusion clearance technique with regard to RBF, GFR and FF. The infusion clearance technique had a higher agreement with the urinary clearance method than the thermodilution method. For estimations of RBF and GFR, the between-group errors were 33% and 43% comparing infusion clearance with urinary clearance and 65% and 67% comparing thermodilution with urinary clearance.Conclusions The infusion clearance method had the highest reproducibility and the highest agreement with the urinary clearance reference method. The renal vein thermodilution technique is less reliable in the ICU setting due to poor repeatability and poor agreement with the reference method.  相似文献   
4.

Background

Physiotherapy is an important part of treatment after severe brain injuries and stroke, but its effect on intracranial and systemic hemodynamics is minimally investigated. Therefore, the aim of this study was to assess the effects of an early bedside cycle exercise on intracranial and systemic hemodynamics in critically ill patients when admitted to a neurointensive care unit (NICU).

Methods

Twenty critically ill patients suffering from brain injuries or stroke were included in this study performed in the NICU at Sahlgrenska University Hospital. One early implemented exercise session was performed using a bedside cycle ergometer for 20 min. Intracranial and hemodynamic variables were measured two times before, three times during, and two times after the bedside cycling exercise. Analyzed variables were intracranial pressure (ICP), cerebral perfusion pressure (CPP), mean arterial blood pressure (MAP), heart rate (HR), peripheral oxygen saturation (SpO2), cardiac output (CO), stroke volume (SV), and stroke volume variation (SVV). The cycling intervention was conducted within 7 ± 5 days after admission to the NICU.

Results

Cycle exercise increased MAP (p = 0.029) and SV (p = 0.003) significantly. After exercise CO, SV, MAP, and CPP decreased significantly, while no changes in HR, SVV, SpO2, or ICP were noted when compared to values obtained during exercise. There were no differences in data obtained before versus after exercise.

Conclusion

Early implemented exercise with a bedside cycle ergometer, for patients with severe brain injuries or stroke when admitted to a NICU, is considered to be a clinically safe procedure.
  相似文献   
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Recombinant vectors carrying DNA fragments from the BamHI E region of the B95-8 Epstein-Barr virus (EBV) genome were transfected into COS-1 cells, and the transient expression of EBV-encoded nuclear antigens (EBNAs) was analyzed by using polyvalent human antisera and rabbit antibodies to synthetic peptides. Vector DNA containing two rightward open reading frames in the BamHI E fragment, BERF2a and BERF2b, induced the expression of a nuclear antigen identical serologically and with respect to size to the larger of the two polypeptides previously designated as EBNA4 in B95-8 cells. An antigen corresponding to the smaller polypeptide was induced in cells transfected with constructs that contained two neighboring reading frames, BERF3 and BERF4. This antigen also reacted with a rabbit antiserum to the synthetic peptide 203, deduced from BERF4. Thus, the findings show that the two components of the EBNA4 doublet in B95-8 cells are encoded by separate genes. The antigen encoded by BERF2a and/or BERF2b has been designated as EBNA4 and the antigen encoded by BERF3 and/or BERF4 has been designated as EBNA6. Polyvalent human antisera detected EBNA4 and EBNA6 in 9 of 11 lymphoid cell lines carrying independent EBV isolates. In the remaining two lines, either EBNA4 or EBNA6 was not detectable.  相似文献   
7.
Large Epstein-Barr virus (EBV) DNA restriction fragments corresponding to regions transcribed in transformed, proliferating cells were cloned in a cosmid derivative of the dominant-acting selection vector pSV2-gpt. Recombinant vectors carrying the EcoRI A fragment of EBV DNA were modified in the region corresponding to the deletion of the virion DNA in the non-transforming viral substrain P3HR-1, to create a series of recombinants lacking parts of this region. The recombinant vectors were introduced into 3T3 mouse fibroblasts under selective conditions, and resistant clones shown to contain EBV DNA sequences were analyzed for the expression of EBV-related antigens detectable by direct, indirect, and anticomplement immunofluorescence techniques. Cells that contained the BamHI K fragment expressed the EBV-determined nuclear antigen (EBNA) as expected. Cells transfected with recombinant vectors containing the BamHI W, Y, and H fragment part of the EcoRI A fragment also express a nuclear antigen detectable with certain anti-EBNA-positive human sera in anticomplement immunofluorescence tests. The BamHI WYH-induced EBNA polypeptide is similar in size to the EBNA2 polypeptide in Raji cells, as shown by gel electrophoresis and immunoblotting. The antigen is not detected in cells transfected with EcoRI A-derived vectors in which the BamHI H fragment has been deleted or in cells transformed with vectors carrying the BamHI H fragment alone. Direct and indirect immunofluorescence did not reveal the presence of antigens associated with productive infection in any of the EBV DNA-transfected fibroblast clones.  相似文献   
8.
Objective: Pulmonary hypertension (PH), defined as a pulmonary vascular resistance (PVR) >2.5 Wood units (WU) and (or) a transpulmonary gradient (TPG) >12 mmHg, is an established risk factor for mortality in heart transplantation. Elevated PVR in heart transplant candidates can be reduced using a left ventricular assist device (LVAD), and LVAD is proposed to be the treatment of choice for candidates with PH. We analyzed the effect on PVR of pretransplant LVAD therapy in patients with PH and compared posttransplant outcome with matched controls. Long-term survival was compared between heart transplant recipients with mild, moderate or severe PH and patients with no PH. Methods: Heart transplant recipients 1988–2007 (n = 405) were reviewed and divided into two groups with respect to pretransplant PVR: <2.5 WU (n = 148) and >2.5 WU (n = 158). From the group with PH, patients subjected to pretransplant LVAD therapy (n = 11) were analyzed with respect to PVR at implant and at transplant and, with respect to outcome, compared to matched historical controls (n = 22). Patients with PH without LVAD treatment (n = 147) were stratified into three subgroups: mild, moderate and severe PH and survival according to Kaplan–Meier was analyzed and compared to patients with no PH. Results: LVAD therapy reduced PVR from 4.3 ± 1.6 to 2.0 ± 0.6 WU, p < 0.05. Three cases of perioperative heart failure required mechanical support whereas one control patient developed perioperative right heart failure requiring mechanical support. The incidence of other perioperative complications was comparable between groups. There was no difference in survival between LVAD patients and controls, 30-day survival was 82% and 91%, respectively and 4-year survival was 64% and 82%, respectively. Conclusions: Pretransplant LVAD therapy reduces an elevated PVR in heart transplant recipients, but there was no statistically significant difference in posttransplant survival in patients with PH with, or without LVAD therapy. The study revealed no differences in survival in patients regardless of the severity of the PH.  相似文献   
9.
OBJECTIVE: Gastroesophageal reflux disease has been reported to be a common burden on health-care resources in the Western world, but its manifestations in the general population are as yet unclear. The aim of this study was to estimate the prevalence of, and to identify the risk factors for gastroesophageal reflux symptoms (GERS) and erosive esophagitis (EE) in the adult population of two Swedish municipalities. MATERIAL AND METHODS: A random sample (n =3000) of the adult population (20-81 years of age) of two Swedish municipalities (n =21,610) was surveyed using a validated postal questionnaire assessing gastrointestinal symptoms. The response rate was 74%. A subsample (n = 1000) of the responders was subsequently invited, in random order, for esophago-gastro-duodenoscopy with evaluation of GERS, risk factors and tests for Helicobacter pylori. RESULTS: GERS were reported by 40.0% and EE was found in 15.5% of the population that had undergone endoscopy. Of those with GERS, 24.5% had EE while 36.8% of those with EE reported no GERS. Hiatus hernia and obesity remained significant risk factors for GERS and/or EE, with or without symptoms in a main effect model (OR up to 14 at EE). Those with active H. pylori infection had a higher risk of GERS without EE than those without H. pylori infection (OR = 1.71 (1.23 2.38)). CONCLUSIONS: GERS and EE (of which one-third is asymptomatic) are highly prevalent in the Swedish adult population. H. pylori infection seems to play a role in the manifestations of gastroesophageal reflux.  相似文献   
10.
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