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51.
Alharbi A Almadi M Barkun A Martel M;REASON Investigators 《Journal canadien de gastroenterologie》2012,26(4):187-192
BACKGROUND:
Patients with upper gastrointestinal bleeding (UGIB) require an early, tailored approach best guided by knowledge of the bleeding lesion, especially a variceal versus a nonvariceal source.OBJECTIVE:
To identify, by investigating a large national registry, variables that would be predictive of a variceal origin of UGIB using clinical parameters before endoscopic evaluation.METHODS:
A retrospective study was conducted in 21 Canadian hospitals during the period from January 2004 until the end of May 2005. Consecutive charts for hospitalized patients with a primary or secondary discharge diagnosis of UGIB were reviewed. Data regarding demographics, including historical, physical examination, initial laboratory investigations, endoscopic and pharmacological therapies administered, as well as clinical outcomes, were collected. Multivariable logistic regression modelling was performed to identify clinical predictors of a variceal source of bleeding.RESULTS:
The patient population included 2020 patients (mean [± SD] age 66.3±16.4 years; 38.4% female). Overall, 215 (10.6%) were found to be bleeding from upper gastrointestinal varices. Among 26 patient characteristics, variables predicting a variceal source of bleeding included history of liver disease (OR 6.36 [95% CI 3.59 to 11.3]), excessive alcohol use (OR 2.28 [95% CI 1.37 to 3.77]), hematemesis (OR 2.65 [95% CI 1.61 to 4.36]), hematochezia (OR 3.02 [95% CI 1.46 to 6.22]) and stigmata of chronic liver disease (OR 2.49 [95% CI 1.46 to 4.25]). Patients treated with antithrombotic therapy were more likely to experience other causes of hemorrhage (OR 0.44 [95% CI 0.35 to 0.78]).CONCLUSION:
Presenting historical and physical examination data, and initial laboratory tests carry significant predictive ability in discriminating variceal versus nonvariceal sources of bleeding. 相似文献52.
Nikpay M ?eda O Tremblay J Petrovich M Gaudet D Kotchen TA Cowley AW Hamet P 《Hypertension research》2012,35(6):585-591
Links between substance use habits, obesity, stress and the related cardiovascular outcomes can be, in part, because of loci with pleiotropic effects. To investigate this hypothesis, we performed genome-wide mapping in 119 multigenerational families from a population in the Saguenay-Lac-St-Jean region with a known founder effect using 58,000 single-nucleotide polymorphisms and 437 microsatellite markers to identify genetic components of the following factors: habitual alcohol, tobacco and coffee use; response to mental and physical stress; obesity-related traits; and heart rate (HR) and blood pressure (BP) measures. Habitual alcohol and/or tobacco users had attenuated HR responses to mental stress compared with non-users, whereas hypertensive individuals had stronger HR and systolic BP responses to mental stress and a higher obesity index than normotensives. Genetic mappings uncovered numerous shared genes among substance use, stress response, obesity and hemodynamic traits, including CAMK4, CNTN4, DLG2, FHIT, GRID2, ITPR2, NOVA1 and PRKCE, forming network of interacting proteins, sharing synaptic function and display higher and patterned expression profiles in brain-related tissues; moreover, pathway analysis of shared genes pointed to long-term potentiation. Subgroup genetic mappings uncovered additional shared synaptic genes, including CAMK4, CNTN5 and DNM3 (hypertension-specific); CNTN4, DNM3, FHIT and ITPR1 (sex-specific), having protein interactions with genes driven from general analysis. In summary, consistent with the observed phenotypic correlations, we found substantial overlap among genomic determinants of these traits in synapse, which supports the notion that the neural synapse may be a shared interface behind substance use, stress, obesity, HR, BP as well as the observed sex- and hypertension-specific genetic differences. 相似文献
53.
54.
Effect of verapamil on bronchial goblet cells of asthma: an experimental study on sensitized animals
Khakzad MR Mirsadraee M Mohammadpour A Ghafarzadegan K Hadi R Saghari M Meshkat M 《Pulmonary pharmacology & therapeutics》2012,25(2):163-168
IntroductionGoblet cell hyperplasia (GCH) and mucus hypersecretion in the airway is recognized as an important contributor to morbidity and mortality in asthma and COPD. Verapamil is a calcium channel blocker that binds to the alpha-subunit of L-type calcium channels and inhibits the mucin gene via the calmodulin and CaM kinase pathway. The objective of this study was to determine the in vivo effect of verapamil on GCH and eosinophilic inflammation in sensitized mice.MethodsMale BALB/c mice were sensitized to ovalbumin using the standard method. Two groups of animals were received verapamil via an intramuscular injection: 1-low dose (0.5 mg/kg/day for two weeks), 2-high dose (1.5 mg/kg/day for two weeks). Serum and bronchoalveolar lavage fluid (BALF) was collected and analyzed for inflammatory cells, interferon-γ and IL-4. The left lung was sent for histopathological evaluation, especially for periodic acid-Schiff (PAS), to identify goblet cells in the epithelium. The degree of inflammatory cell infiltration, including eosinophils, mucus plugging, and smooth muscle thickness of the airways were classified on a semi quantitative scale.ResultsInflammatory cell infiltration in peribronchial and perivascular areas was observed in all sensitized groups. Eosinophils percentage in the BALF significantly decreased in verapamil-treated mice compared with sensitized mice (from 19.8% in asthmatic to 5.4% for low dose and 4.4% for high dose). The ratio of airway goblet cells per epithelial cells were significantly lower in verapamil-treated mice versus sensitized mice (1.57 ± 1.30% for low dose; 1.50 ± 0.93% for high dose versus 12.93 ± 7.55%, P < 0.05, respectively). Mucus production of goblet cells decreased significantly in verapamil-treated mice versus sensitized mice (mean score was 1.45 ± 0.30 for low dose; 0.81 ± 1.00 for high dose versus 2.85 ± 0.86 in the sensitized control group, P < 0.05, respectively). The concentration of serum and BALF-IFN-γ in verapamil-treated mice markedly increased by the verapamil treatment when compared to sensitized mice (15.1 ± 0.43 versus 4.7 ± 0.96, P < 0.05 and 91.8 ± 47.7 versus 14.8 ± 4.6, P < 0.01, respectively).ConclusionVerapamil is a useful drug with therapeutic targeting on GCH and a potential way to limit mucous production and improve bronchial inflammation. 相似文献
55.
Saeed Rayati Elham Khodaei Parinaz Nafarieh Majid Jafarian Bahareh Elmi Andrzej Wojtczak 《RSC advances》2020,10(29):17026
In this study, a novel Mn(iii)–Schiff base complex was synthesized and characterized. The structure of this complex was determined to be a deformed octahedral coordination sphere by single-crystal X-ray diffraction analysis. The Mn(iii)–Schiff base complex was supported on silica-coated iron magnetic nanoparticles via axial coordination by one-step complex anchoring to produce a heterogenized nanocatalyst. After this, the complex was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), and powder X-ray diffraction (XRD). Moreover, atomic absorption spectroscopy was used to determine the amount of the loaded metal. The heterogenized nanocatalyst effectively catalyzed the oxidation of a broad range of sulfides and alkenes with H2O2 in the presence of a glassy carbon electrode, applying voltage to the reaction mixture. The results showed that the application of a potential to the reaction mixture could significantly decrease the reaction time when compared with the case of similar chemical oxidation reactions. In addition, an excellent value of turnover frequency (17 750 h−1) was achieved for the electrochemical oxidation of styrene. Moreover, the nanocatalyst showed good recoverability without significant loss of its activity within six successive runs in the electrochemical oxidation of methyl phenyl sulfide and cyclooctene. The electrochemical properties and stability of Fe3O4@SiO2-[MnL(OAc)] were investigated by cyclic voltammetry measurements and chronoamperometry technique.A Mn–Schiff base complex supported on silica-coated iron magnetic nanoparticles was used for the electrochemical oxidation of sulfides and alkenes. 相似文献
56.
Mahsa Asadniaye Fardjahromi Amir Razmjou Graham Vesey Fatemeh Ejeian Balarka Banerjee Subhas Chandra Mukhopadhyay Majid Ebrahimi Warkiani 《RSC advances》2020,10(34):20118
Metal–organic frameworks (MOFs) have high porosity, large surface area, and tunable functionality and have been widely used for drug loading. The aim of this study was to exploit unique features of zeolitic imidazolate framework-8 (ZIF8) to develop an innovative composite microcarrier (MC) for human mesenchymal stem cells (hMSCs) adhesion and proliferation. ZIF8 MCs were prepared by immobilization of polydopamine/polyethyleneimine (PDA/PEI) and ZIF8 on the surface of polystyrene beads. The chemical properties of MCs such as coating stability and homogeneity were characterized by different techniques such as ATR-FTIR, XRD, EDX, SEM, and contact angle. The prepared MCs were tested using human adipose-derived mesenchymal stem cells (hADSCs) in both static and dynamic conditions, and results were compared to a commercially available MC (Star-Plus), polydopamine coated MCs and amine-functionalized MCs as a control. Results show that PDA/PEI/ZIF8 coated MCs (in short: ZIF8 MCs) provides an excellent biocompatible environment for hADSCs adhesion and growth. In conclusion, ZIF8 MCs represent suitable and low-cost support for hADSCs culture and expansion, which can maximize cell yield and viability while preserving hADSCs multipotency. The present findings have revealed this strategy has the potential for chemical and topographical modification of MCs in tissue engineering applications.Mussel inspired ZIF8 microcarriers with high surface area, biocompatibility, and nanoscale surface roughness are applied to enhance mesenchymal stem cell attachment and proliferation in 3D cell culture. 相似文献
57.
Eldad Elnekave MD Joseph P. Erinjeri MD Karen T. Brown MD Raymond H. Thornton MD Elena N. Petre MD Majid Maybody MD Mary A. Maluccio MD Meier Hsu MS Constantinos T. Sofocleous MD George I. Getrajdman MD Lynn A. Brody MD Stephen B. Solomon MD William Alago MD Yuman Fong MD William R. Jarnagin MD Anne M. Covey MD 《Annals of surgical oncology》2013,20(9):2881-2886
Background
Resection has been the standard of care for patients with solitary hepatocellular carcinoma (HCC). Transarterial embolization and percutaneous ablation are alternative therapies often reserved for suboptimal surgical candidates. Here we compare long-term outcomes of patients with solitary HCC treated with resection versus combined embo-ablation.Methods
We previously reported a retrospective comparison of resection and embo-ablation in 73 patients with solitary HCC <7 cm after a median follow-up of 23 months. This study represents long-term updated follow-up over a median of 134 months.Results
There was no difference in survival among Okuda I patients who underwent resection versus embo-ablation (66 vs 58 months, p = .39). There was no difference between the groups in the rate of distant intrahepatic (p = .35) or metastatic progression (p = .48). Surgical patients experienced more complications (p = .004), longer hospitalizations (p < .001), and were more likely to require hospital readmission within 30 days of discharge (p = .03).Conclusion
Over a median follow up of more than 10 years, we found no significant difference in overall survival of Okuda 1 patients with solitary HCC <7 cm who underwent surgical resection versus embo-ablation. Our data suggest that there may be a greater role for primary embo-ablation in the treatment of potentially resectable solitary HCC. 相似文献58.
59.
Aderbal S. Aguiar Jr. Fabrine S. M. Tristão Majid Amar Caroline Chevarin Laurence Lanfumey Raymond Mongeau Olga Corti Rui D. Prediger Rita Raisman-Vozari 《Neurotoxicity research》2013,24(2):280-287
The loss of nigral dopaminergic neurons in Parkinson’s disease (PD) is believed to result from interactions between genetic susceptibility and environmental factors. Although loss-of-function mutations in the parkin gene cause early-onset familial PD, the hybrid 129Sv-C57BL/6 parkin-deficient mice did not display spontaneous degeneration of the nigrostriatal pathway or enhanced vulnerability to neurotoxicity induced by 6-hydroxydopamine (6-OHDA) or intraperitoneal 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) intoxication. We aimed to re-evaluate the role of parkin in a pure C57BL/6 background after an acute intranasal (i.n.) MPTP administration, a new route of toxin delivery to the brain that mimics environmental exposure to neurotoxins. We found that the deficiency of parkin gene modifies the d-amphetamine-induced locomotion in saline-treated animals. Intranasal MPTP induced Parkinsonism in parkin+/+ mice, through depletion of striatal dopamine, decreased number of dopaminergic neurons in the substantia nigra, and decreased d-amphetamine-induced hyperlocomotion. Additionally, the deletion of the parkin gene in a pure C57BL/6 background did not lead to increased vulnerability to i.n. MPTP-induced neurotoxicity. Moreover, the i.n. MPTP induced nigral astrogliosis predominantly in the pars reticulata in wild type and parkin?/? mice. Taken together, these results showed that the absence of parkin did not modify the vulnerability of nigrostriatal dopaminergic pathway after i.n. MPTP intoxication, suggesting that independently of mouse strain, the endogenous parkin is not required for protection of this system. These findings also suggest that the development of familial parkin-linked PD is not associated with exposure to environmental factors that specifically affects the dopaminergic system. 相似文献
60.