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991.
Schiele TM Rieber J König A Leibig M Erhard I Theisen K Siebert U Klauss V 《The American journal of cardiology》2004,94(7):917-921
In-stent restenosis (ISR), especially after vascular brachytherapy, is a therapeutic challenge. Sirolimus-eluting stent implantation is a promising new option for the treatment of patients with ISR. The efficacy of sirolimus-eluting stent implantation for the treatment of patients with their first episodes of ISR and with recurrent ISR due to the failure of vascular brachytherapy was compared using intravascular ultrasound imaging. 相似文献
992.
Inhaled iloprost reverses vascular remodeling in chronic experimental pulmonary hypertension 总被引:10,自引:0,他引:10
Schermuly RT Yilmaz H Ghofrani HA Woyda K Pullamsetti S Schulz A Gessler T Dumitrascu R Weissmann N Grimminger F Seeger W 《American journal of respiratory and critical care medicine》2005,172(3):358-363
RATIONALE: Inhaled iloprost is an effective therapy for pulmonary arterial hypertension (PAH). However, no study to date has addressed the effects of inhaled iloprost on changes to pulmonary vascular structure that occur in PAH. OBJECTIVES: The present study was designed to investigate chronic antiremodeling effects of inhaled iloprost in monocrotaline (MCT)-induced PAH in rats. Methods: Four weeks after a single injection of MCT, after full establishment of PAH, rats were nebulized with iloprost at a dose of 6 microg . kg(-1) . day(-1), or underwent sham nebulization with saline. RESULTS: After 2 weeks of inhalation therapy, right ventricular pressure and pulmonary vascular resistance were reversed in rats treated with iloprost, but not in sham-treated control animals. Systemic arterial pressure was unaffected. In addition, right heart hypertrophy, the degree of pulmonary artery muscularization, and the medial wall thickness of intraacinar pulmonary arteries regressed in response to iloprost. Furthermore, the MCT-induced increase in matrix metalloproteinase-2 and -9 activities and tenascin-C expression was suppressed. CONCLUSIONS: We conclude that the inhalation of iloprost reverses PAH and vascular structural remodeling in MCT-treated rats. This regimen suggests the possibility of an antiremodeling therapy in PAH. 相似文献
993.
Differentiation of in vitro-modified human peripheral blood monocytes into hepatocyte-like and pancreatic islet-like cells 总被引:16,自引:0,他引:16
994.
OBJECTIVE: Acquired aplastic anemia (AA) is a rare disorder characterized by pancytopenia and hypocellular bone marrow. Though experimental and clinical data suggest that AA represents a T cell-mediated disease, neither the immune response nor the nature of inciting antigen(s) have been characterized so far. The identification of a restricted T cell repertoire by PCR techniques in total lymphocyte populations supports an antigen-driven T cell response. In order to investigate the clonal composition, we analyzed the gene rearrangements of the T cell receptor (TCR) variable beta chain (Vbeta) at the single-cell level. PATIENTS AND METHODS: CD3(+) T lymphocytes were micromanipulated from peripheral blood and bone marrow samples of 8 AA patients and healthy controls. Subsequently amplified VDJ gene segments of the TCRVbeta chain were analyzed for functional rearrangements. More than 500 functionally rearranged TCR loci were studied for Vbeta/Jbeta gene segment usage and molecular composition of the complementary-determining region 3 (CDR3). RESULTS: In comparison to healthy controls, the Vbeta sequences confirmed a highly restricted T cell repertoire in AA patients at the single-cell level. Both in bone marrow and peripheral blood a predominance of Vbeta13 and Jbeta2S7 was observed. Furthermore, individual clonal T-cell expansion was identified in the majority of patients. However, deduced CDR3 amino acid sequences revealed a high variability without common motifs among the 8 patients. CONCLUSION: Individual clonal T-cell expansion with high diversity of the antigen-binding sites among the analyzed patients argues for the predominance of private inciting epitopes in AA. 相似文献
995.
Kaemmerer H Fratz S Braun SL Koelling K Eicken A Brodherr-Heberlein S Pietrzik K Hess J 《The American journal of cardiology》2004,94(6):825-828
A high percentage of cyanotic adults (37%) with cyanotic congenital cardiac disease (CCD) presented with depleted iron stores (13 of 52) or latent iron deficiency (6 of 52), even in a CCD center in which cyanotic patient phlebotomy is mostly avoided. In many of these patients, hypochromia and microcytosis was frequent, whereas hyperchromia and macrocytosis were relatively common.Furthermore, 50% of patients presented with hyperhomocysteinemia, possibly related to folate or B vitamin deficiencies, which may increase red blood cell size and color, explaining the lack of microcytosis and hypochromia in many cyanotic patients with iron deficiency. 相似文献
996.
Lethen H Tries HP Brechtken J Kersting S Lambertz H 《The American journal of cardiology》2003,91(4):412-417
Transthoracic Doppler echocardiography (TDE) has been described as a feasible and accurate technique to noninvasively assess coronary flow reserve (CFR) in the left anterior descending artery (LAD). This study was designed to evaluate whether serial assessment of CFR in the LAD using TDE allows detection of restenosis after previously performed angioplasty. Thirty-three consecutive patients with single-vessel coronary artery disease of the LAD scheduled for angioplasty underwent assessment of coronary flow velocity at rest and during adenosine-induced hyperemia in the distal LAD using high-frequency TDE. CFR was calculated as the ratio of hyperemic to basal systolic/diastolic mean velocity. Investigations were performed before and immediately after angioplasty, and at the time of control angiography after 3 months. CFR results by TDE were compared with intracoronary Doppler guide wire measurements. Adequate pulse-wave Doppler signals to measure CFR were obtained in 30 patients (91%) using TDE. There was close correlation between echocardiographically and intracoronary derived CFR results (r = 0.80, 0.79, and 0.87 before angioplasty, early after, and at 3- month control angiography, respectively; p <0.001). Using a cut-off value of CFR < or =2.0 to identify significant coronary artery disease, TDE detected LAD restenosis with a sensitivity of 89% and specificity of 90%. Thus, high-frequency TDE is a feasible technique to noninvasively assess CFR in the LAD with results closely corresponding to invasive measurements. Defining a cut-off value of CFR < or =2.0, the technique has the potential to reliably detect LAD stenosis after coronary intervention. 相似文献
997.
Estner HL Hessling G Ndrepepa G Luik A Schmitt C Konietzko A Ucer E Wu J Kolb C Pflaumer A Zrenner B Deisenhofer I 《The American journal of cardiology》2008,101(3):332-337
Complex fractionated atrial electrographic (CFAE) catheter ablation is a new approach for the treatment of atrial fibrillation (AF). It is unclear if acute results of this approach correspond to long-term outcome. The purpose of this study was to prospectively assess acute and long-term successes of an ablation approach combining pulmonary vein isolation (PVI) and ablation of CFAE areas for treatment of persistent AF. PVI and ablation of CFAE areas were performed in 35 patients with persistent AF (30 men, 57+/-9 years of age). At the end of the ablation procedure AF had terminated in 23 of 35 patients (66%) by conversion to sinus rhythm (8 of 23 patients, 35%) or organization to atrial tachycardia (15 of 23 patients, 65%). AF persisted in 12 of 35 patients (34%). At the end of the follow-up period (19+/-12 months), sinus rhythm was present in 26 of 35 patients (74%), including 9 patients with a repeat procedure. This group of 26 patients consisted of 7 of 8 patients (88%) with acute sinus rhythm after the first ablation, 11 of 15 patients (73%) with organization, and 8 of 12 patients (66%) with ongoing AF (p=0.32). In conclusion, a combined approach of PVI and CFAE ablation in persistent AF leads to acute AF termination in 66% and long-term maintenance of sinus rhythm in 74% of cases. However, long-term outcome was not predictable by acute results of the ablation procedure. 相似文献
998.
Brunilda Alushi Frederik Beckhoff David Leistner Marcus Franz Markus Reinthaler Barbara E. Stähli Andreas Morguet Hans R. Figulla Torsten Doenst Francesco Maisano Volkmar Falk Ulf Landmesser Alexander Lauten 《JACC: Cardiovascular Imaging》2019,12(4):591-601
Objectives
The authors investigated the development of pulmonary hypertension (PH), predictors of PH regression, and its prognostic impact on short, mid-, and long-term outcomes in patients undergoing transcatheter aortic valve replacement (TAVR) for severe aortic stenosis (AS).Background
PH represents a common finding in patients with AS. Although TAVR is frequently associated with regression of PH, the predictors of reversible PH and its prognostic significance remain uncertain.Methods
In this study, 617 consecutive patients undergoing TAVR between 2009 and 2015 were stratified per baseline tertiles of pulmonary artery systolic pressure (PASP) as follows: normal (PASP <34 mm Hg), mild-to-moderate (PASP ≥34 mm Hg and <46 mm Hg), and severe PASP elevation (PASP ≥46 mm Hg). After TAVR, 520 patients with PH at discharge were stratified according to the presence or absence of PASP reduction. Primary outcome was all-cause mortality at 30 days, 1 year, and long-term follow-up at a maximum of 5.9 years.Results
In patients with both mild-to-moderate and severe PH at baseline, PASP decreased significantly at discharge (ΔPASP 3.0 ± 9.3 mm Hg and 12.0 ± 10.0 mm Hg, respectively) and 1 year (ΔPASP 5.0 ± 9.7 mm Hg and 18.0 ± 14.0 mm Hg, respectively). At a median follow-up of 370 days (interquartile range [IQR]: 84 to 500 days), the risk of all-cause mortality was similar among baseline PASP groups at all time intervals evaluated. After TAVR, a significant regression of PH was observed in 46% of patients. Contrarily, patients with residual PH had a higher risk of all-cause mortality at 30 days (hazard ratio [HR]: 3.49, 95% confidence interval [CI]: 1.74 to 6.99; p < 0.001), 1 year (HR: 3.12, 95% CI: 2.06 to 4.72; p < 0.001), and long-term (HR: 2.47, 95% CI: 1.74 to 3.49; p < 0.001). Left ventricular ejection fraction (LVEF) >40% (odds ratio [OR]: 3.56, 95% CI: 2.24 to 5.65; p < 0.001), baseline PASP ≥46 mm Hg (OR: 3.26, 95% CI: 2.07 to 5.12; p < 0.001), absence of concomitant tricuspid regurgitation (TR) ≥ moderate (OR: 0.53, 95% CI: 0.34 to 0.84; p < 0.001), and logistic EuroSCORE <25% (OR: 1.59, 95% CI: 1.04 to 2.45; p = 0.03) were independent predictors of PASP reduction.Conclusions
In most patients with PH and AS, TAVR is associated with a significant early and late reduction of PASP. Patients with reversible PH after TAVR are at lower risk of all-cause mortality at early, mid-, and long-term follow-up. Therefore, the presence of PH should not preclude treatment with TAVR. 相似文献999.
Prabhjot Singh Shilpa Vijayakumar Andreas Kalogeroupoulos Javed Butler 《Current heart failure reports》2018,15(2):44-52
Purpose of review
This review discusses the integral role of the nitric oxide (NO) pathway in the pathophysiology of heart failure (HF). We emphasize potential therapeutic targets in the NO pathway and review contemporary clinical trials evaluating these novel therapeutic options.Recent findings
Nitrates, neprilysin inhibitors, and phosphodiesterase (PDE) inhibitors have all proven to be efficacious in HF patients with systolic dysfunction, with the former two classes of medications producing a net mortality benefit. However, neither PDE inhibitors nor nitrates have demonstrated significant clinical benefit in patients with HF with preserved ejection fraction (HFpEF), and neprilysin inhibitors have yet to be evaluated in this population. Soluble guanylate cyclase (sGC) stimulators have shown significant promise in all HF patients, leading to improvements in both quality of life scores and exercise capacity. Conversely, sGC activators have limited clinical utility in HF, owing largely to safety concerns of hypotension. Inorganic nitrates and nitrites, meanwhile, may be emerging as potential therapies for the HFpEF population.Summary
The advent of novel therapies targeting the NO pathway is beginning to create a paradigm shift in the treatment of the HF patient. These therapies offer a promising outlook for the future, with hopes of reducing HF-associated morbidity and mortality.1000.