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Andrew R. Hoellein MD Christopher A. Feddock MD Charles H. Griffith III MD MSPH John F. Wilson PhD Donald R. Barnett MD MSPH Pat F. Bass III MD MS T. Shawn Caudill MD MSPH 《Journal of general internal medicine》2004,19(5P2):562-565
Due to recent public debate and newly imposed resident work hour restrictions, we decided to investigate the relationship of resident call status to their ambulatory patients' satisfaction. Resident continuity clinic patients were asked to rate their level of satisfaction on a 10-point Likert-type scale. Using multiple regression approaches, these data were then assessed as a function of resident call status. We found that in 646 patient encounters, patient satisfaction scores were significantly less when the resident was postcall, 8.99 ± 1.8, than when not postcall, 9.31 ± 1.3. We herein discuss etiologies and implications of these findings for both patient care and medical education. 相似文献
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Sanjeev Kakar Thomas A Einhorn Siddharth Vora Lincoln J Miara Gregory Hon Nathan A Wigner Daniel Toben Kimberly A Jacobsen Maisa O Al-Sebaei Michael Song Philip C Trackman Elise F Morgan Louis C Gerstenfeld George L Barnes 《Journal of bone and mineral research》2007,22(12):1903-1912
Studies have shown that systemic PTH treatment enhanced the rate of bone repair in rodent models. However, the mechanisms through which PTH affects bone repair have not been elucidated. In these studies we show that PTH primarily enhanced the earliest stages of endochondral bone repair by increasing chondrocyte recruitment and rate of differentiation. In coordination with these cellular events, we observed an increased level of canonical Wnt-signaling in PTH-treated bones at multiple time-points across the time-course of fracture repair, supporting the conclusion that PTH responses are at least in part mediated through Wnt signaling. INTRODUCTION: Since FDA approval of PTH [PTH(1-34); Forteo] as a treatment for osteoporosis, there has been interest in its use in other musculoskeletal conditions. Fracture repair is one area in which PTH may have a significant clinical impact. Multiple animal studies have shown that systemic PTH treatment of healing fractures increased both callus volume and return of mechanical competence in models of fracture healing. Whereas the potential for PTH has been established, the mechanism(s) by which PTH produces these effects remain elusive. MATERIALS AND METHODS: Closed femoral fractures were generated in 8-wk-old male C57Bl/6 mice followed by daily systemic injections of either saline (control) or 30 microg/kg PTH(1-34) for 14 days after fracture. Bones were harvested at days 2, 3, 5, 7, 10, 14, 21, and 28 after fracture and analyzed at the tissue level by radiography and histomorphometry and at the molecular and biochemical levels level by RNase protection assay (RPA), real-time PCR, and Western blot analysis. RESULTS: Quantitative muCT analysis showed that PTH treatment induced a larger callus cross-sectional area, length, and total volume compared with controls. Molecular analysis of the expression of extracellular matrix genes associated with chondrogenesis and osteogenesis showed that PTH treated fractures displayed a 3-fold greater increase in chondrogenesis relative to osteogenesis over the course of the repair process. In addition, chondrocyte hypertrophy occurred earlier in the PTH-treated callus tissues. Analysis of the expression of potential mediators of PTH actions showed that PTH treatment significantly induced the expression of Wnts 4, 5a, 5b, and 10b and increased levels of unphosphorylated, nuclear localized beta-catenin protein, a central feature of canonical Wnt signaling. CONCLUSIONS: These results showed that the PTH-mediated enhancement of fracture repair is primarily associated with an amplification of chondrocyte recruitment and maturation in the early fracture callus. Associated with these cellular effects, we observed an increase in canonical Wnt signaling supporting the conclusion that PTH effects on bone repair are mediated at least in part through the activation of Wnt-signaling pathways. 相似文献
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D A Curson S R Hirsch S D Platt R W Bamber T R Barnes 《British medical journal (Clinical research ed.)》1986,293(6549):726-728
A randomised double blind placebo controlled trial is the most reliable method of assessing putative new developments in medical treatment. In schizophrenia, however, some clinicians believe that relapse contributes to long term deterioration and therefore that patients exposed to either placebo or an inactive new treatment may be put at a disadvantage in the long run if the trial leads to an additional relapse. A seven year follow up of patients included in a randomised placebo controlled trial of fluphenazine decanoate, in which 66% of the group given placebo relapsed compared with 8% of those who received the active drug, permitted examination of any long term adverse consequences in those patients who had received placebo. Seventy six (94%) of the 81 patients in the original trial were followed up. At the end of the follow up period there were no consistent or important differences in any measure of clinical or social outcome between the patients who had received placebo and those who had received the active drug. This negative finding has implications for the debate on the risk of placebo controlled trials of maintenance treatment in chronic schizophrenia. 相似文献
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A P Milstone L M Brumble J Barnes W Estes J E Loyd R N Pierson S Dummer 《The European respiratory journal》2006,28(1):131-137
The frequency and complications of respiratory viral infections (RVI) were studied in 50 ambulatory lung transplant patients during a single winter season, using viral antigens, viral cultures and PCR of nasal washes or bronchoalveolar lavages. Patients' survival, episodes of acute rejection and occurrence of bronchiolitis obliterans (BO) or BO syndrome (BOS) were monitored for 1 yr after the study. Overall, 32 (64%) patients had 49 symptomatic episodes. Documented infections included eight due to respiratory syncytial virus (RSV), one due to parainfluenza virus (PIV) and 10 due to influenza (FLU). Four of the FLU infections were serological rises without symptoms. Overall, 17 (34%) patients had documented viral infection; four patients had lower respiratory involvement and two (one RSV, one PIV) were hospitalised for aerosolised ribavirin treatment. After 1 yr there were three (6%) deaths unrelated to RVI. BO or BOS had occurred in one (6%) out of 17 patients with and three (12%) out of 33 without RVI. Respiratory viruses infected one-third of ambulatory lung transplant recipients in a single season. In conclusion, respiratory viral infection was not associated with subsequent graft dysfunction. Larger prospective studies are required to better define the acute and long-term morbidity of these infections. 相似文献