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101.
The removal of urokinase from the market has created a dilemma for interventionists and vascular surgeons treating patients with acute limb threatening ischemia due to arterial thrombosis or embolization. Reteplase is a newer, fibrin-specific thrombolytic agent with properties that make it an attractive alternative to urokinase. We report two cases of successful treatment of acute, limb threatening ischemia with intra-arterial Reteplase therapy.  相似文献   
102.
Estrogen can inhibit intimal proliferation and accelerate endothelial regeneration after angioplasty. This suggests that estrogen may prevent in-stent restenosis. Unlike other therapies to prevent restenosis, estrogen may also not delay endothelial regrowth, thereby avoiding the risk of late stent thrombosis. The purpose of this work was to determine the effect of a 17beta-estradiol-eluting stent on neointimal formation in a porcine model. Each artery of six pigs was randomized to either a control, low-dose, or high-dose 17beta-estradiol-eluting stent. All animals were sacrificed at 30 days for histopathological analysis. There was a 40% reduction in intimal area in the high-dose stents compared with control stents (2.54 +/- 1.0 vs. 4.13 +/- 1.1 mm(2), for high dose vs. control, respectively; P < 0.05). There was complete endothelial regeneration at 30 days and similar inflammatory response to stenting on histopathology in all the stent groups. This is the first study to show that 17beta-estradiol-eluting stents are associated with reduced neointimal formation without affecting endothelial regeneration in the pig model of in-stent restenosis. Estrogen-coated stents may have a potential benefit in the prevention and treatment of in-stent restenosis.  相似文献   
103.
104.

Objectives

To compare the outcomes of initial one-stent (1S) versus dedicated two-stent (2S) strategies in complex bifurcation percutaneous coronary intervention (PCI) using everolimus-eluting stents (EES).

Background

PCI of true bifurcation lesions is technically challenging and historically associated with reduced procedural success and increased restenosis. Prior studies comparing initial one-stent (1S) versus dedicated two-stent (2S) strategies using first-generation drug-eluting stents have shown no reduction in ischemic events and more complications with a 2S strategy.

Methods

We performed a retrospective study of 319 consecutive patients undergoing PCI at a single referral center with EES for true bifurcation lesions, defined by involvement of both the main vessel (MV) and side branch (SB). Baseline, procedural characteristics, quantitative coronary angiography and clinical outcomes in-hospital and at one year were compared for patients undergoing 1S (n = 175) and 2S (n = 144) strategies.

Results

Baseline characteristics were well-matched. 2S strategy was associated with greater SB acute gain (0.65 ± 0.41 mm vs. 1.11 ± 0.47 mm, p < 0.0001). In-hospital serious adverse events were similar (9% with 2S vs. 8% with 1S, p = 0.58). At one year, patients treated by 2S strategy had non-significantly lower rates of target vessel revascularization (5.8% vs. 7.4%, p = 0.31), myocardial infarction (7.8% vs. 12.2%, p = 0.31) and major adverse cardiovascular events (16.6% vs. 21.8%, p = 0.21).

Conclusion

In this study of patients undergoing PCI for true coronary bifurcation lesions using EES, 2S strategy was associated with superior SB angiographic outcomes without excess complications or ischemic events at one year.  相似文献   
105.
Objectives: Global burden of childhood asthma has increased in the past few decades, particularly in low-income countries. In Pakistan, there is a lack of community-based epidemiological studies estimating the burden of asthma among children. This study determined the prevalence and predictors of asthma among children 3–17 years of age in Karachi, Pakistan. Methods: A two-stage community-based representative cross-sectional survey was conducted in Karachi from March 2012 to April 2013 comprising 1046 children aged 3–17 years. Of 7500 clusters, 80 were randomly selected, and of these, 15 children per cluster were enrolled randomly. A translated and pre-tested version of International Study of Asthma and Allergies in Children questionnaire was administered. Results: The overall prevalence of asthma among study participants was 10.2% (95% CI: 8.4–12.0). Asthma was more likely to occur among boys (adj. OR: 2.5, 95% CI: 1.6–4.0), children in the younger age group (3–7 years) (adj. OR: 2.9, 95% CI: 1.7–4.8), those living in households with ill-ventilated kitchens (adj. OR: 1.8, 95% CI: 1.1–3.1), having family history of asthma (adj. OR: 2.3, 95% CI: 1.3–3.9) and those of the Sindhi ethnicity (adj. OR: 2.2, 95% CI: 1.1–4.4). Conclusion: This study is the first robust evidence regarding asthma among children in Pakistan, reporting a high burden in this group. Family history, male gender, Sindhi ethnicity and ill-ventilated kitchen were identified as important predictors of asthma. Targeted preventive measures and intervention studies are required to better understand and reduce the burden of asthma among children in Pakistan.  相似文献   
106.
107.
Intracranial hemorrhage (ICH) is one of the most severe and life-threatening manifestations occurring in the patients with factor XIII (F XIII) deficiency. The aim of this study was to describe the ICH pattern in the patients suffering from F XIII deficiency. In this case series, we investigated 38 patients with severe F XIII deficiency in south of Iran from January to May 2012. ICH pattern, neurologic complications, efficacy of treatment, and incidence of recurrence were reported. The site of ICH was intraparenchymal in 35 patients (92.1 %), subdural in 2 patients (5.2 %), and epidural hemorrhage in 1 patient (2.6 %). Besides, neurologic complications occurred in 21 patients (55.2 %), including locomotor disability in 8, psychological impairment in 7, mental disorders in 5, speech impairment in 4, and visual impairment in 2. Prophylaxis was started with a dose of 10 IU/kg Fibrogammin every 4–6 weeks for all the patients, except for one. All the patients on prophylaxis showed good response without any episodes of recurrence, except for one. The most frequent site of ICH in our patients was intraparenchymal. It seems that long-term prophylactic treatment with a dose of 10 IU/kg Fibrogammin could be effective in the prevention of CNS bleeding in the patients with F XIII deficiency. Moreover, all the patients with severe F XIII deficiency even without severe bleeding symptoms are recommended to undergo prophylactic treatment.  相似文献   
108.

Introduction

Periapical infections secondary to pulpal necrosis are associated with bacterial contamination of the pulp. Porphyromonas endodontalis, a gram-negative organism, is considered to be a pulpal pathogen. P. gingivalis is phylogenetically related to P. endodontalis and synthesizes several classes of novel complex lipids that possess biological activity, including the capacity to promote osteoclastogenesis and osteoclast activation. The purpose of this study was to extract and characterize constituent lipids of P. endodontalis and evaluate their capacity to promote proinflammatory secretory responses in the macrophage cell line, RAW 264.7, as well as their capacity to promote osteoclastogenesis and inhibit osteoblast activity.

Methods

Constituent lipids of both organisms were fractionated by high-performance liquid chromatography and were structurally characterized using electrospray mass spectrometry or electrospray-mass spectrometry/mass spectrometry. The virulence potential of P. endodontalis lipids was then compared with known biologically active lipids isolated from P. gingivalis.

Results

P. endodontalis total lipids were shown to promote tumor necrosis factor alpha secretion from RAW 264.7 cells, and the serine lipid fraction appeared to account for the majority of this effect. P. endodontalis lipid preparations also increased osteoclast formation from RAW 264.7 cells, but osteoblast differentiation in culture was inhibited and appeared to be dependent on Toll-like receptor 2 expression.

Conclusions

These effects underscore the importance of P. endodontalis lipids in promoting inflammatory and bone cell activation processes that could lead to periapical pathology.  相似文献   
109.
The purpose of this work is to enhance the proton conductivity and fuel cell performance of sulfonated poly(phthalazinone ether ketone) (SPPEK) as a proton exchange membrane through the application of SrTiO3 perovskite nanoparticles. Nanocomposite membranes based on SPPEK and SrTiO3 perovskite nanoparticles were prepared via a casting method. The highest proton conductivity of nanocomposite membranes obtained was 120 mS cm−1 at 90 °C and 95% RH. These enhancements could be related to the hygroscopic structure of SrTiO3 perovskite nanoparticles and the formation of hydrogen bonds between nanoparticles and water molecules. The satisfactory power density, 0.41 W cm−2 at 0.5 V and 85 °C, of the nanocomposite membrane (5 wt% content of nanoparticles) confirms their potential for application in the PEM fuel cells.

The purpose of this work is to enhance the proton conductivity and fuel cell performance of sulfonated poly(phthalazinone ether ketone) (SPPEK) as a proton exchange membrane through the application of SrTiO3 perovskite nanoparticles.  相似文献   
110.
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