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101.
Abed H Rahn DD Lowenstein L Balk EM Clemons JL Rogers RG;Systematic Review Group of the Society of Gynecologic Surgeons 《International urogynecology journal》2011,22(7):789-798
Introduction and hypothesis
This study describes the incidence, risk factors, and treatments of graft erosion, wound granulation, and dyspareunia as adverse events following vaginal repair of pelvic organ prolapse with non-absorbable synthetic and biologic graft materials. 相似文献102.
Avigdor Klinger DMD PhD Anat Tadir DMD Amal Halabi MSc Lior Shapira DMD PhD 《Clinical implant dentistry and related research》2011,13(1):64-70
Background: The surface qualities of dental implants appear to modulate osteoblasts’ growth and differentiation, affecting bone healing. During manufacturing of implants, the surface quality is affected by industrial processes. Purpose: To examine the effect of manufacturing procedures on the growth and differentiation of human osteoblast‐like cells, Saos‐2. Materials and Methods: Saos‐2 cells were cultured on titanium (Ti) disks. Cell growth was examined using the XTT assay, and cell differentiation was tested by alkaline phosphatase (ALP) activity and osteocalcin secretion. The following variables were examined: roughening of the surface by sandblasting and acid‐etching, aging of the acid used for etching, fluoride modification of the surface, and the type of the packaging material. Results: An inverse relationship was noted between Saos‐2 growth and ALP activity on the tested surfaces. Roughening of the surface tended to decrease cell proliferation and to increase differentiation. Immersion of up to 200 cycles in acid decreased proliferation and increased differentiation. Cells grown on fluoride‐modified surfaces exhibited more ALP activity as compared to the unmodified surfaces. No difference was noted between the three packaging materials tested. Conclusions: The data suggests that industrial processes may affect the behavior of osteoblast‐like cells around titanium implants and should be monitored carefully by bioassays. 相似文献
103.
Chackartchi T Iezzi G Goldstein M Klinger A Soskolne A Piattelli A Shapira L 《Clinical oral implants research》2011,22(5):473-480
Objectives: To compare the amount of newly formed bone after sinus floor augmentation with two different particle sizes of bovine bone mineral (BBM) using clinical, micro‐computerized tomography (CT) and histological techniques. Methods: Bilateral sinus floor augmentations were performed in 10 patients. Six to 9 months later, bone samples were retrieved and analyzed. Results: Results: Both groups were not different in vertical bone height achieved after augmentation, post‐operative complications and maximal torque for the insertion of implants. Micro‐CT measurements could not detect a statistically significant difference in bone volume between the groups (with a tendency for new more bone in the small granules group). Histomorphometric analysis revealed that both granule sizes produced the same pattern of bone formation, surrounding the graft granules, and producing a shape of a network, “bridging” between the BBM particles. Multi‐nucleated giant cells, probably osteoclasts, were observed directly on the BBM particle surface in both groups. The osteoclast‐like cells preferred the small‐size BBM particles and not the large particles both in the small‐size and the large‐size granules group. Conclusion: Both sizes of BBM granules preformed equally and achieved the aim of the sinus floor augmentation procedure clinically and histologically. To cite this article: Chackartchi T, Iezzi G, Goldstein M, Klinger A, Soskolne A, Piattelli A, Shapira L. Sinus floor augmentation using large (1–2 mm) or small (0.25–1 mm) bovine bone mineral particles: a prospective, intra‐individual controlled clinical, micro‐computerized tomography and histomorphometric study.Clin. Oral Impl. Res 22 , 2011; 473–480doi: 10.1111/j.1600‐0501.2010.02032.x 相似文献
104.
BACKGROUND: The antibacterial and anti-inflammatory properties of Dead Sea magnesium chloride (MgCl(2)), citrus oil, and their combination were investigated. Citrus oil is composed of monoterpenes, in particular D-limonene, which is known to inhibit growth of bacteria, fungi, and certain parasites. METHODS: Inhibition of Porphyromonas gingivalis in vitro was used to evaluate the antibacterial effect of a mixture of Dead Sea magnesium chloride and citrus oil and of each of the components. A subcutaneous chamber model in mice was used to assess the anti-inflammatory effect of the mixture and the individual components. Leukocyte migration, tumor necrosis factor-alpha (TNF-alpha) secretion, and interleukin (IL)-10 secretion were determined. Hydrocortisone was used as a positive control. RESULTS: Citrus oil had an antibacterial effect with a minimal inhibitory concentration (MIC) of 1 mg/ml, whereas MgCl(2) at concentrations up to 10 mg/ml did not exhibit any antibacterial activity. However, a mixture of 10 mg/ml MgCl(2) and 0.25 mg/ml citrus oil dramatically increased inhibition of bacterial growth. The combination of MgCl(2) and the citrus oil resulted in lower levels of TNF-alpha and leukocyte migration while maintaining the levels of IL-10 compared to the control. CONCLUSION: These findings suggest that a mixture of citrus oil and MgCl(2) could be used as a natural antibacterial and anti-inflammatory agent. 相似文献
105.
Reconstitution of the transition from lamellipodium to filopodium in a membrane-free system
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Haviv L Brill-Karniely Y Mahaffy R Backouche F Ben-Shaul A Pollard TD Bernheim-Groswasser A 《Proceedings of the National Academy of Sciences of the United States of America》2006,103(13):4906-4911
The cellular cytoskeleton is a complex dynamical network that constantly remodels as cells divide and move. This reorganization process occurs not only at the cell membrane, but also in the cell interior (bulk). During locomotion, regulated actin assembly near the plasma membrane produces lamellipodia and filopodia. Therefore, most in vitro experiments explore phenomena taking place in the vicinity of a surface. To understand how the molecular machinery of a cell self-organizes in a more general way, we studied bulk polymerization of actin in the presence of actin-related protein 2/3 complex and a nucleation promoting factor as a model for actin assembly in the cell interior separate from membranes. Bulk polymerization of actin in the presence of the verprolin homology, cofilin homology, and acidic region, domain of Wiskott-Aldrich syndrome protein, and actin-related protein 2/3 complex results in spontaneous formation of diffuse aster-like structures. In the presence of fascin these asters transition into stars with bundles of actin filaments growing from the surface, similar to star-like structures recently observed in vivo. The transition from asters to stars depends on the ratio [fascin]/[G actin]. The polarity of the actin filaments during the transition is preserved, as in the transition from lamellipodia to filopodia. Capping protein inhibits star formation. Based on these experiments and kinetic Monte Carlo simulations, we propose a model for the spontaneous self-assembly of asters and their transition into stars. This mechanism may apply to the transition from lamellipodia to filopodia in vivo. 相似文献
106.
Lior Cohen Noa Koffman Hanoch Meiri Yosef Yarom Ilan Lampl Adi Mizrahi 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(14):5665-5670
The ability of the brain to adapt to environmental demands implies that neurons can change throughout life. The extent to which single neurons actually change remains largely unstudied, however. To evaluate how functional properties of single neurons change over time, we devised a way to perform in vivo time-lapse electrophysiological recordings from the exact same neuron. We monitored the contralateral and ipsilateral sensory-evoked spiking activity of individual L2/3 neurons from the somatosensory cortex of mice. At the end of the first recording session, we electroporated the neuron with a DNA plasmid to drive GFP expression. Then, 2 wk later, we visually guided a recording electrode in vivo to the GFP-expressing neuron for the second time. We found that contralateral and ipsilateral evoked responses (i.e., probability to respond, latency, and preference), and spontaneous activity of individual L2/3 pyramidal neurons are stable under control conditions, but that this stability could be rapidly disrupted. Contralateral whisker deprivation induced robust changes in sensory-evoked response profiles of single neurons. Our experiments provide a framework for studying the stability and plasticity of single neurons over long time scales using electrophysiology. 相似文献
107.
Yakov Goldich Yaniv Barkana Orly Wussuku Lior Arie L. Marcovich Ami Hirsh Isaac Avni David Zadok 《Canadian journal of ophthalmology. Journal canadien d'ophtalmologie》2014
Objective
To assess the long-term effects of treatment of progressive keratoconus with ultraviolet A-riboflavin collagen cross-linking (CXL).Design
This was a prospective clinical study.Participants
Seventeen eyes of 17 patients with progressive keratoconus were treated with CXL.Methods
Patients were examined preoperatively, at week 1, months 1, 3, 6, 9, 12, 24, and 36 after treatment. We assessed uncorrected visual acuity (UCVA) and best spectacle-corrected visual acuity (BSCVA), refraction, biomicroscopy and fundus appearance, intraocular pressure, endothelial cell density (ECD), corneal topography, minimal corneal thickness (MCT), macular optical coherence tomography, axial length, and corneal biomechanics with the ocular response analyzer.Results
Comparing the 36-month time point results with pretreatment values, we found that UCVA and BSCVA were unchanged. Steepest meridian keratometry (D) and mean cylinder (D) did not show significant change compared with pretreatment values but showed a slight increase as compared with the 24-month time point (53.9 vs 51.7 vs 52.5, and 10.5 vs 8.1 vs 9.2 before, at 24 months, and at 36 months, respectively). Axial length (mm) showed an elongation trend throughout the follow-up period (24.56 vs 24.61 [p = 0.04] vs 24.71 [p = 0.05], before, at 24 months, and at 36 months, respectively). No significant change was observed in ECD, corneal hysteresis and corneal resistance factor, MCT, or foveal thickness.Conclusions
Three-year results after CXL show stable visual acuity, stable corneal thickness, and stable corneal biomechanical parameters. The decreasing trend in keratometry values that was observed during the first 2 years after CXL was no longer evident. Longer follow-up is needed to decide whether it is a first sign of loss of achieved stability and resumption of keratoconus progression. 相似文献108.
Karban A Krivoy N Elkin H Adler L Chowers Y Eliakim R Efrati E 《Digestive diseases and sciences》2011,56(7):2081-2087
Background
The involvement of oxidant/antioxidant imbalance in the development of inflammatory bowel disease (IBD) is well documented. Two members of the glutathione S-transferase (GST) family of enzymes, GSTM1 and GSTT1, known to take part in cellular protection against electrophiles, demonstrate common deletion variants (termed null) associated with impaired enzyme function. 相似文献109.
King CL Adams JH Xianli J Grimberg BT McHenry AM Greenberg LJ Siddiqui A Howes RE da Silva-Nunes M Ferreira MU Zimmerman PA 《Proceedings of the National Academy of Sciences of the United States of America》2011,108(50):20113-20118
Plasmodium vivax (Pv) is a major cause of human malaria and is increasing in public health importance compared with falciparum malaria. Pv is unique among human malarias in that invasion of erythrocytes is almost solely dependent on the red cell's surface receptor, known as the Duffy blood-group antigen (Fy). Fy is an important minor blood-group antigen that has two immunologically distinct alleles, referred to as Fy(a) or Fy(b), resulting from a single-point mutation. This mutation occurs within the binding domain of the parasite's red cell invasion ligand. Whether this polymorphism affects susceptibility to clinical vivax malaria is unknown. Here we show that Fy(a), compared with Fy(b), significantly diminishes binding of Pv Duffy binding protein (PvDBP) at the erythrocyte surface, and is associated with a reduced risk of clinical Pv in humans. Erythrocytes expressing Fy(a) had 41-50% lower binding compared with Fy(b) cells and showed an increased ability of naturally occurring or artificially induced antibodies to block binding of PvDBP to their surface. Individuals with the Fy(a+b-) phenotype demonstrated a 30-80% reduced risk of clinical vivax, but not falciparum malaria in a prospective cohort study in the Brazilian Amazon. The Fy(a+b-) phenotype, predominant in Southeast Asian and many American populations, would confer a selective advantage against vivax malaria. Our results also suggest that efficacy of a PvDBP-based vaccine may differ among populations with different Fy phenotypes. 相似文献
110.
Brimberg L Benhar I Mascaro-Blanco A Alvarez K Lotan D Winter C Klein J Moses AE Somnier FE Leckman JF Swedo SE Cunningham MW Joel D 《Neuropsychopharmacology》2012,37(9):2076-2087
Group A streptococcal (GAS) infections and autoimmunity are associated with the onset of a spectrum of neuropsychiatric disorders in children, with the prototypical disorder being Sydenham chorea (SC). Our aim was to develop an animal model that resembled the behavioral, pharmacological, and immunological abnormalities of SC and other streptococcal-related neuropsychiatric disorders. Male Lewis rats exposed to GAS antigen exhibited motor symptoms (impaired food manipulation and beam walking) and compulsive behavior (increased induced-grooming). These symptoms were alleviated by the D2 blocker haloperidol and the selective serotonin reuptake inhibitor paroxetine, respectively, drugs that are used to treat motor symptoms and compulsions in streptococcal-related neuropsychiatric disorders. Streptococcal exposure resulted in antibody deposition in the striatum, thalamus, and frontal cortex, and concomitant alterations in dopamine and glutamate levels in cortex and basal ganglia, consistent with the known pathophysiology of SC and related neuropsychiatric disorders. Autoantibodies (IgG) of GAS rats reacted with tubulin and caused elevated calcium/calmodulin-dependent protein kinase II signaling in SK-N-SH neuronal cells, as previously found with sera from SC and related neuropsychiatric disorders. Our new animal model translates directly to human disease and led us to discover autoantibodies targeted against dopamine D1 and D2 receptors in the rat model as well as in SC and other streptococcal-related neuropsychiatric disorders. 相似文献