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31.
Ankylosing spondylitis (AS) is a chronic inflammatory disease, characterized by axial arthritis in which the genetic-environmental factors seem to be involved in the pathogenesis of the disease. This study was performed to investigate the role of polymorphisms of the programmed cell death 1 (PDCD1) gene on susceptibility to AS. In this study, 161 Iranian patients with AS and 208 normal controls were enrolled; two single-nucleotide polymorphisms (SNPs) of the PDCD1 gene PD-1.3 (G, A) in nucleotide position +7146 of intron 4 and PD-1.9 (C, T) in nucleotide +7625 of exon 5 were studied. Analysis of PD-1.3 revealed that 82% of patients and 79% of controls had GG genotype, while GA and AA genotypes were detected in 17% and 0.6% of patients, respectively, and 20% and 1.4% of controls, respectively. Moreover, the genotype CC (PD-1.9) was present in 92% of patients and 97% of controls. Although these differences were not statistically significant between patients and controls, comparisons of genotypes frequencies in the AS patients, based on human leukocyte antigen (HLA)-B27, revealed that all patients who had CT genotype (PD-1.9) were HLA-B27 positive, whereas 30% of patients with CC genotype were HLA-B27 negative. There was no evidence of association for PDCD1 SNPs with AS in our study, but CT genotype (PD-1.9) seems to be associated with HLA-B27 positivity in the patients with AS.  相似文献   
32.

Purpose

An ideal anastomosis between hollow viscera should be easily performed, strong, and operator independent. We hypothesized that transluminal attraction between magnets in the intestine could be harnessed to create an intestinal compression anastomosis (magnamosis) with these characteristics. We further hypothesized that variation of attraction force and geometry of compression would affect the quality of the intestinal anastomosis.

Methods

We designed a self-orienting device composed of 2 neodymium-iron-boron magnets affixed to polytetrafluoroethylene moldings. Two topologies were evaluated: one designed with ‘uniform’ compression and the other with ‘gradient’ compression. Sixteen young adult pigs (Sus scrofa) underwent laparotomy with creation of a magnetic side-to-side anastomosis: 8 with the uniform device and 8 with the gradient device. Each also had a stapled anastomosis, and 5 had an additional hand-sutured anastomosis. Animals were euthanized at 1, 2, and 3 weeks after operation, then anastomoses were compared on the basis of gross appearance, histology, functional radiography, and mechanical integrity.

Results

All magnetic devices formed patent anastomoses without leak. One stapled anastomosis resulted in a contained leak. Mechanical integrity of magnetic anastomoses was not statistically significantly different from staple or suture counterparts, and there was a trend toward greater strength with magnetic anastomoses. Comparison between device types revealed the gradient device trended toward greater strength and earlier patency (67% vs 33% at 1 week). There was no evidence of stenosis, and histologic examination demonstrated tissue remodeling with mucosal and serosal apposition across the magnamoses.

Conclusions

The magnetic compression anastomosis (magnamosis) device is a safe and effective means of sutureless full-thickness intestinal anastomosis with serosal apposition in a pig model. Gradient compression is superior to uniform compression. This technique is compatible with endoscopic and natural orifice approaches.  相似文献   
33.
BackgroundThe purpose of this pilot study was to determine the utility of acoustic cardiography for the optimization of atrioventricular (AV) and interventricular (VV) delays in cardiac resynchronization therapy (CRT).Methods and ResultsWe evaluated 14 patients (86% male, mean age 64 ± 9 years, mean time since implant 15 ± 18 months). Subjects were enrolled >10 weeks after CRT implant. Spiroergometry and 2-dimensional/3-dimensional echocardiography were used to assess cardiac performance for “out-of-the-box” settings (baseline settings: AV 120 ms, VV 0 ms) versus optimal settings (determined by acoustic cardiography). Cardiac performance measurements were performed 6 weeks after settings were modified. Optimal AV/VV settings were determined based on the lowest electromechanical activation time (EMAT, the time from the onset of QRS to the mitral valve component of the first heart sound). Statistical analysis was performed using a paired 2-tailed Student's t-test. In comparison to “out-of-the-box” settings, AV/VV delay optimization with acoustic cardiography improved cardiac performance as indicated by significant changes in work capacity, maximum oxygen uptake, oxygen pulse, ejection fraction, end-systolic volume, and velocity-time integral in left ventricular outflow tract.ConclusionsAV and VV optimization by acoustic cardiography produces significant improvements in objective clinical and hemodynamic parameters in comparison to typical “out-of-the-box” settings.  相似文献   
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Background:  In literature, the use of ketamine for the preventative analgesia in the management of postoperative pain is controversial. The purpose of the present study was the clinical assessment of the efficacy of preincisional peritonsillar infiltration of two doses of ketamine on postoperative pain relief compared with peritonsillar saline in children undergoing adenotonsillectomy.
Methods/materials:  Seventy-five ASA physical status I and II patients, aged 3–12 years, scheduled for adenotonsillectomy were enrolled in this randomized, double-blind, placebo-controlled study. Patients were divided into three groups of 25 each and received a local peritonsillar infiltration of 0.9% saline (group S), ketamine 0.5 mg·kg−1 (group K1), or ketamine 1 mg·kg−1 (group K2). All medications were 2 ml in volume which was applied 1 ml per tonsil 3 min prior to tonsillectomy. The Children's Hospital of Eastern Ontario Pain Scale (CHEOPS) and Wilson sedation scale were used to evaluate pain levels and sedative conditions, respectively.
Results:  Group S had significantly higher CHEOPS scores than group K1 and K2. Both K1 and K2 groups had comparable scores, which were not statistically significant ( P  > 0.05). During 24 h after surgery, 16 patients in group S and no patients in groups K1 or K2 needed analgesics ( P  <   0.001).
Conclusions:  A 0.5 or 1 mg·kg−1 dose of ketamine given at approximately 3 min before surgery by peritonsillar infiltration provides efficient pain relief during 24 h after surgery without side-effects in children undergoing adenotonsillectomy.  相似文献   
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37.
Aims: It has been shown that optimizing atrioventricular (AV) andinterventricular (VV) delay improves cardiac performance inpatients with biventricular pacemakers. However, there is nostandard method for optimization available yet. The aim of thisstudy was to compare echocardiographic parameters—displacementimaging, A wave duration, and aortic velocity time integral(VTI)—and acoustic cardiography derived electromechanicalactivation time (EMAT) using different approaches of AV andVV delay optimization. We tested whether the initial optimizationof the AV interval followed by VV optimization at that optimalAV interval or initial optimization of the VV interval followedby AV optimization at the determined optimal VV interval wasaccurate and consistent, and how this compared to testing everyconceivable combination of AV and VV intervals available. Methods and results: A group of 20 patients with biventricular pacemakers was included.Displacement imaging, A wave duration, and aortic VTI were determinedat different combinations of AV (100, 150, 200, 250 ms) andVV (RV40, 0, LV40 ms) intervals. If AV duration was determinedfirst, displacement imaging identified the best setting in 8/20,aortic VTI in 10/20, A duration in 13/20, and EMAT in 18/20patients. With VV duration determined first, the best settingwas more difficult to identify regardless of the method used.There was a poor agreement in optimal AV and VV delays of thedifferent methods, and there was no single patient in whom allfour methods yielded the same delay combination. Conclusion: It is advisable to measure a full grid of AV and VV delays toidentify optimal settings rather than optimizing one of thetwo delays first. Different techniques for delay optimizationresulted in different optimal delay combinations.  相似文献   
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Evidence indicates that very late stent thrombosis (> 1 year) occurs more frequently in drug-eluting stents than in bare metal stents after discontinuation of clopidogrel. We present a case of an 83 year old man with an LAD in-stent thrombosis 41 months after stenting with a sirolimus-eluting stent in whom clopidogrel was discontinued after 6 months based on these days' guidelines. In-stent thrombus was aspirated and intracoronary ultrasound (ICUS) showed significant in-stent restenosis which had narrowed the minimal lumen diameter by 1 mm. The lesion was stented with a bare metal stent. The patient was discharged after recovery and had no recurrence of stent thrombosis in one month follow-up. We recommended indefinite dual antiplatelet therapy with aspirin and clopidogrel.  相似文献   
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