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991.
Right ventricular dysfunction in chronic heart failure patients   总被引:1,自引:0,他引:1  
AIM: To evaluate any differences in haemodynamic and echocardiographic parameters in patients with both left (LV) and right ventricular (RV) systolic dysfunction and in patients with isolated LV systolic dysfunction. STUDY GROUP: One hundred patients with RV systolic dysfunction defined as peak velocity of tricuspid annular motion in systole (Sa)<11.5 cm/s, and 55 patients without RV systolic dysfunction Sa>11.5 cm/s. All patients had LV systolic dysfunction, LV ejection fraction (EF) below 40%, NYHA II-IV. METHODS: LV diameters, volumes and EF were measured by echocardiography. Patients underwent tissue Doppler imaging (TDI) of tricuspid annular motion with measurement of peak systolic velocity (Sa), peak early (Ea) and peak late (Aa) diastolic velocities. Right heart catheterization was also performed. RESULTS: Patients with RV systolic dysfunction did not differ from those without RV systolic dysfunction in terms of LV function. Patients with RV systolic dysfunction had larger RV dimension 30.6+/-5.8 vs. 33.9+/-6.7 mm, p<0.002. The patients with RV systolic dysfunction had higher values on right heart catheterization: MPAP 29.6+/-12.1 vs. 24.9+/-11.4 mm Hg, p<0.02, PCWP 20.8+/-10.0 vs. 17.3+/-9.3 mm Hg, p<0.03, PVR 189.9+/-123.3 vs. 137.7+/-94.9 dyn s cm(-5), p<0.008, CVP 7.7+/-5.6 vs. 5.1+/-3.9 mm Hg, p<0.002. The patients with RV systolic dysfunction had more pronounced diastolic dysfunction measured by TDI: Ea 9.9+/-2.3 vs. 11.4+/-2.5 cm/s, p<0.0001 and Aa 13.1+/-4.0 vs. 16.5+/-4.7 cm/s, p<0.000007. CONCLUSION: Patients with heart failure and both left and right ventricular systolic dysfunction showed more serious findings on central haemodynamics as well as more pronounced right ventricular diastolic dysfunction than those with isolated left ventricular systolic dysfunction.  相似文献   
992.
993.
IMP-8 metallo-β-lactamase was identified in Klebsiella pneumoniae sequence type 252 (ST252), isolated in a Portuguese hospital in 2009. blaIMP-8 was the first gene cassette of a novel class 3 integron, In1144, also carrying the blaGES-5, blaBEL-1, and aacA4 cassettes. In1144 was located on a ColE1-like plasmid, pKP-M1144 (12,029 bp), with a replication region of limited nucleotide similarity to those of other RNA-priming plasmids, such as pJHCMW1. In1144 and pKP-M1144 represent an interesting case of evolution of resistance determinants in Gram-negative bacteria.  相似文献   
994.
We report 17 cytopenic patients with myelodysplastic syndrome (MDS) of refractory anaemia (RA) subtype with hyper-, normo- or hypo-cellular bone marrow (BM), who were treated with cyclosporin A (CyA). Substantial haematological response was observed in 14 patients (82%): their anaemia improved and all transfusion-dependent patients achieved transfusion independence. Complete trilineage recovery was observed in four patients (23%). The CyA therapy has not yet failed in any of the 14 successfully treated patients during follow-up times ranging from 5 to 30 months. CyA was well tolerated in 14 patients; serious side-effects required termination of the therapy in three patients in whom the blood count rapidly deteriorated to former levels upon cessation of therapy. Two patients benefited from a combination therapy of CyA and erythropoietin. Six patients experienced various autoimmune phenomena. CyA could thus offer an alternative treatment for certain MDS patients with RA regardless of hyper-, normo- or hypo-cellularity of bone marrow (BM). The mechanism of the beneficial effect of CyA is discussed and remains the subject of an ongoing study.  相似文献   
995.
996.
Urolithiasis is a frequent and in many cases serious disease. Proper analysis of kidney stone composition is crucial for appropriate treatment and prevention of disease recurrence. In this work, scanning electron microscopy (SEM) coupled with energy-dispersive spectroscopy was applied for a study of 30 samples covering the most common types of human kidney stones. The results are analyzed and evaluated in terms of applicability of the method for both routine kidney stone analysis as well as collecting of specific data. The method provides complex information about studied samples including morphology of the stones and of the present crystals or their aggregates. It also brings information on elemental composition of the phases. After application of standardization, quantitative microanalysis with detection limits of 400?ppm (Mg, P, S, Cl, K, Ca), 500?ppm (Na) and 1200?ppm (F) was obtained. Compositional mapping with EDS shows the elemental distribution within a sample. This study demonstrated that information on morphology and chemistry acquired by these methods was highly reliable for identification of phases, even when present in small amounts. It provided information on kidney stone structure, relationships between phases, major and minor element content, and variations in chemical composition related to the growth of the stones. SEM represents a powerful tool in urinary stone analysis, since a single facility can produce a wide spectrum of information. It can be suggested as a basic method used for routine urinary stone identification, whilst bringing additional detailed information that cannot be obtained by other methods.  相似文献   
997.
Context: Methanol poisoning induces acute optic neuropathy with possible long-term visual damage.

Objective: To study the dynamics and key determinants of visual pathway functional changes during 4 years after acute methanol poisoning.

Methods: A total of 42 patients with confirmed methanol poisoning (mean age 45.7?±?4.4 years) were examined 4.9?±?0.6, 25.0?±?0.6, and 49.9?±?0.5 months after discharge. The following tests were performed: visual evoked potential (VEP), retinal nerve fiber layer (RNFL) measurement, brain magnetic resonance imaging (MRI), complete ocular examination, biochemical tests, and apolipoprotein E (ApoE) genotyping.

Results: Abnormal VEP P1 latency was registered in 18/42 right eyes (OD) and 21/42 left eyes (OS), abnormal N1P1 amplitude in 10/42 OD and OS. Mean P1 latency shortening during the follow-up was 15.0?±?2.0?ms for 36/42 (86%) OD and 14.9?±?2.4?ms for 35/42 (83%) OS, with maximum shortening up to 35.0?ms. No significant change of mean N1P1 amplitude was registered during follow-up.

A further decrease in N1P1 amplitude ≥1.0 mcV in at least one eye was observed in 17 of 36 patients (47%) with measurable amplitude (mean decrease ?1.11?±?0.83 (OD)/?2.37?±?0.66 (OS) mcV versus ?0.06?±?0.56 (OD)/?0.83?±?0.64 (OS) mcV in the study population; both p?ApoE4 allele carriers had lower global and temporal RNFL thickness and longer initial P1 latency compared to the non-carriers (all p?p?r?=?0.384; p?=?.013) and brain hemorrhages (r?=?0.395; p?=?.011).

Conclusions: Improvement of optic nerve conductivity occurred in more than 80% of patients, but evoked potential amplitude tended to decrease during the 4 years of observation. ApoE4 allele carriers demonstrated lower RNFL thickness, longer P1 latency, and more frequent methanol-induced brain damage compared to non-carriers.  相似文献   
998.
Surface-initiated atom transfer radical polymerization (SI-ATRP) was used to modify graphene oxide (GO) particles with poly(butyl methacrylate) (PBMA) chains. This procedure facilitated the single-step fabrication of a hybrid material with tailored conductivity for the preparation of a suspension in silicone oil with enhanced sedimentation stability and improved electrorheological (ER) activity. PBMA was characterized using various techniques, such as gel permeation chromatography (GPC) and 1H NMR spectroscopy. Thermogravimetric analysis through on-line investigation of the Fourier transform infrared spectra, together with transmission electron microscopy, X-ray photoelectron microscopy, and atomic force microscopy, were successfully used to confirm GO surface modification. The ER performance was investigated using optical microscopy images and steady shear rheometry, and the mechanism of the internal chain-like structure formation was elucidated. The dielectric properties confirmed enhanced ER performance owing to an increase in relaxation strength to 1.36 and decrease in relaxation time to 5 × 10−3 s. The compatibility between GO and silicone oil was significantly influenced by covalently bonded PBMA polymer brushes on the GO surface, showing enhanced compatibility with silicone oil, which resulted in the considerably improved sedimentation stability. Furthermore, a controlled degree of reduction of the GO surface ensured that the suspension had improved ER properties.

Surface-initiated atom transfer radical polymerization (SI-ATRP) was used to modify graphene oxide (GO) particles with poly(butyl methacrylate) (PBMA) chains.  相似文献   
999.
Background: This study was designed to evaluate the outcomes of alcohol septal ablation (ASA) under multicenter and multinational conditions. Methods: Data for 459 patients (age 57 ± 13 years) from nine European centers were prospectively collected and retrospectively analyzed. Results: ASA led to a significant reduction in outflow gradient (PG) and dyspnea [median of PG from 88 (58–123) mm Hg to 21 (11–41) mm Hg; median of NYHA class from 3 (2–3) to 1 (1–2); P < 0.01]. The incidence of 3‐month major adverse events (death, electrical cardioversion for tachyarrhythmias, resuscitation) and mortality was 2.8% and 0.7%, respectively. Permanent pacemakers for post‐ASA complete heart block were implanted in 43 patients (9%). Multivariate analysis identified higher amount of alcohol (however, in generally low‐dose procedures), higher baseline left ventricular ejection fraction and higher age as independent predictors of PG decrease ≥50%. Conclusions: The results of the first European multicenter and multinational study demonstrate that real‐world early outcomes of ASA patients are better than was reported in observations from the first decade after ASA introduction. © 2013 Wiley Periodicals, Inc.  相似文献   
1000.
INTRODUCTION: Cetuximab is a chimeric antibody registered for the therapy of advanced colorectal carcinoma after failure of standard chemotherapy. Rare infusion reactions that resulted in the cessation of therapy have been described after cetuximab administration. CASE DESCRIPTION: We have observed severe infusion reactions accompanied by a loss of consciousness in two patients. The patients were transferred to intensive care unit, and the treatment was continued after administration of corticosteroids under careful monitoring of vital signs without any further serious reactions. In both cases, benefit of therapy with cetuximab could be demonstrated. CONCLUSION: This experience indicates that cetuximab can be continued in patients who experience infusion reactions. Surveillance in the intensive care unit is mandatory during readministration of the drug.  相似文献   
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