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101.
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R. M. Arif Khalil Muhammad Iqbal Hussain Nadia Luqman Fayyaz Hussain Anwar Manzoor Rana Muhammad Saeed Akhtar Rana Farhat Mehmood 《RSC advances》2022,12(7):4395
The first-principles approach has been used while employing the Perdew–Burke–Ernzerhof exchange-correlation functional of generalized gradient approximation (PBE-GGA) along with the Hubbard parameter to study the structural, optoelectronic, mechanical and magnetic properties of titanium-based MAX materials Ti3AC2 (A = P, As, Cd) for the first time. As there is no band gap found between the valence and conduction bands in the considered materials, these compounds belong to the conductor family of materials. A mechanical analysis carried out at pressures of 0 GPa to 20 GPa and the calculated elastic constants Cij reveal the stability of these materials. Elastic parameters, i.e., Young''s, shear and bulk moduli, anisotropy factor and Poisson''s ratio, have been investigated in the framework of the Voigt–Reuss–Hill approximation. The calculated values of relative stiffness are found to be greater than ½ for Ti3PC2 and Ti3AsC2, which indicates that these compounds are closer to typical ceramics, which possess low damage tolerance and fracture toughness. Optical parameters, i.e., dielectric complex function, refractive index, extinction coefficient, absorption coefficient, loss function, conductivity and reflectivity, have also been investigated. These dynamically stable antiferromagnetic materials might have potential applications in advanced electronic and magnetic devices. Their high strength and significant hardness make these materials potential candidates as hard coatings.The first-principles approach has used the Perdew–Burke–Ernzerhof exchange-correlation functional of generalized gradient approximation along with the Hubbard parameter to study various properties of titanium-based MAX materials Ti3AC2 (A = P, As, Cd). 相似文献
103.
Abdurrahman Tufan Rıdvan Mercan Mehmet Engin Tezcan Arif Kaya Berivan Bitik Mehmet Akif Ozturk Seminur Haznedaroglu Berna Goker 《Rheumatology international》2013,33(8):1933-1937
Enthesopathy is pathology of bony insertions of tendons, ligaments or joint capsules. It is a frequent finding in rheumatic diseases, like ankylosing spondylitis (AS) and Behçet’s disease. Musculoskeletal complaints are common in patients with familial Mediterranean fever (FMF), and these could be a clinical manifestation of enthesopathy. Hence, we investigated the possible association between FMF and enthesopathy. Fifty-six patients with FMF and 11 patients with FMF-associated spondyloarthropathy (FMFS) were enrolled. Forty-seven healthy individuals and 36 patients with AS formed the healthy and diseased control groups. Musculoskeletal complaints were meticulously questioned, and all patients underwent a detailed physical and ultrasonographic (US) examination of the lower limbs. US scorings of enthesopathy was performed according to the Glasgow Ultrasound Enthesitis Scoring System (GUESS). Demographic data, disease characteristics, MEFV genotypes and HLA B27 results were retrieved from the medical records. Patient-reported pain and physical examination findings consistent with enthesopathy were frequent in all groups with the highest prevalence in the FMFS group. Heel was the most common region affected in all patient groups. FMF patients harboring M694 V variant had higher GUESS scores compared to patients with other variants (2.78 ± 2.43 vs. 1.37 ± 1.67, p = 0.026). There was no statistically significant difference in the mean ± SD GUESS scores between healthy subjects and those FMF patients with genetic variants other than M694 V (1.38 ± 1.42 vs. 1.37 ± 1.67, p > 0.05). Enthesopathy may not be a feature of general FMF population; rather, it might be specifically associated with the presence of M694 V variant. Our results further support the previous evidence regarding M694 V mutation and spondyloarthropathy association. 相似文献
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In the Caucasian world calcified and stenosed aortic valves are a common disease. Due to increasing life expectancy prevalence of aortic valve disease will increase dramatically. In order to establish alternative therapeutic approaches to valve replacement, we have to get a better understanding of the pathophysiological process and genetic determinations leading to calcified and stenotic valve disease. Exploring these genetic determinations will open new specific fields of therapeutic modulations of the disease process. In the literature, different gene polymorphisms have been characterized to develop calcifications and further stenosis of the aortic valves.Here, congestive polyvalent aortic valve abnormalities without specific genetic determinations (i. e., DiGeorge syndrome or fragile x syndrome), autosomal inherited alterations leading to congestive aortic valve disease (i. e., Williams-Beuren syndrome, Gaucher's disease, tetralogy of Fallot, genetic aberrations of chromosomes 2 and 4 as well as trisomy 18), X- and Y-chromosomal specific alterations (i. e., Turner syndrome), congestive structure-based aortic valve disease (i. e., bicuspid aortic valve with regard to hand-heart syndromes, tetracuspid aortic valve associated with DiGeorge syndrome) and genetic mutations of specific target genes (i. e., epidermal growth factor receptor, NOTCH-1, elastin, angiotensin I conversion enzyme, beta-glucocerebrosidase, interleukin-10, chemokine receptor 5, connective tissue growth factor, transforming growth factor beta1, vitamin D receptor, estrogen receptor-alpha, apolipoproteins A1, B, and E) are summarized.The roles of gene polymorphism in the development of calcified and stenosed aortic valve appear slowly in the understanding of the process leading to the valve disease and are mainly based on studies of supravalvular and bicuspid aortic valve stenoses. New molecular biological methods enabling broad gene expression analyses demonstrate the similarity in the pathophysiology of atherosclerotic vessel inflammation, bone formation/fibrosis, with the processes leading to stenosed and calcified aortic valves. Based on to-date knowledge, further analyses have to be done and will improve understanding of the pathophysiological processes with regard to the development of new therapeutic drug targets. 相似文献
106.
Angèle Nalbandian Arif A. Khan Ruchi Srivastava Katrina J. Llewellyn Baichang Tan Nora Shukr Yasmin Fazli Virginia E. Kimonis Lbachir BenMohamed 《Inflammation》2017,40(1):21-41
Aberrant activation of the NOD-like receptor (NLR) family, pyrin domain-containing protein 3 (NLRP3) inflammasome, triggers a pathogenic inflammatory response in many inherited neurodegenerative disorders. Inflammation has recently been associated with valosin-containing protein (VCP)-associated diseases, caused by missense mutations in the VCP gene. This prompted us to investigate whether NLRP3 inflammasome plays a role in VCP-associated diseases, which classically affects the muscles, bones, and brain. In this report, we demonstrate (i) an elevated activation of the NLRP3 inflammasome in VCP myoblasts, derived from induced pluripotent stem cells (iPSCs) of VCP patients, which was significantly decreased following in vitro treatment with the MCC950, a potent and specific inhibitor of NLRP3 inflammasome; (ii) a significant increase in the expression of NLRP3, caspase 1, IL-1β, and IL-18 in the quadriceps muscles of VCPR155H/+ heterozygote mice, an experimental mouse model that has many clinical features of human VCP-associated myopathy; (iii) a significant increase of number of IL-1β(+)F4/80(+)Ly6C(+) inflammatory macrophages that infiltrate the muscles of VCPR155H/+ mice; (iv) NLRP3 inflammasome activation and accumulation IL-1β(+)F4/80(+)Ly6C(+) macrophages positively correlated with high expression of TDP-43 and p62/SQSTM1 markers of VCP pathology in damaged muscle; and (v) treatment of VCPR155H/+ mice with MCC950 inhibitor suppressed activation of NLRP3 inflammasome, reduced the F4/80(+)Ly6C(+)IL-1β(+) macrophage infiltrates in the muscle, and significantly ameliorated muscle strength. Together, these results suggest that (i) NLRP3 inflammasome and local IL-1β(+)F4/80(+)Ly6C(+) inflammatory macrophages contribute to pathogenesis of VCP-associated myopathy and (ii) identified MCC950 specific inhibitor of the NLRP3 inflammasome with promising therapeutic potential for the treatment of VCP-associated myopathy. 相似文献
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Syazmi Zul Arif Hakimi Saadon Noridah Binti Osman Moviin Damodaran Shan En Liew 《Materials》2022,15(8)
The torrefaction process in the preparation of energy materials has garnered a lot of attention and has been investigated as a means of improving biomass solid fuels. The aim of this study is to study the effect of the temperature and holding time of two biomass samples: wild Napier grass and oil palm petiole. The torrefied samples are operated in a pyrolysis reactor to replicate the torrefaction procedure. The temperature parameter ranges between 220 and 300 °C while the holding time of the reaction parameter ranges from 10 to 50 min. It is found that with increasing temperature and time, the moisture content and number of O and H atoms decrease and also cause both mass and energy yield to decrease. It is found that the calorific value and the energy density increase with both parameters, which shows that optimization is needed for better solid fuel production. Between the two parameters, temperature changes have more significant effects on the torrefied samples. The optimized temperature and time are found to be 260 °C and 30 min, respectively. The usage of the pyrolysis reactor for the torrefaction reaction has been proven to serve as a good option due to similar product characteristics and equivalent results. 相似文献
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