全文获取类型
收费全文 | 4998篇 |
免费 | 356篇 |
国内免费 | 57篇 |
专业分类
耳鼻咽喉 | 36篇 |
儿科学 | 105篇 |
妇产科学 | 104篇 |
基础医学 | 670篇 |
口腔科学 | 40篇 |
临床医学 | 434篇 |
内科学 | 1125篇 |
皮肤病学 | 100篇 |
神经病学 | 463篇 |
特种医学 | 249篇 |
外科学 | 1073篇 |
综合类 | 33篇 |
一般理论 | 4篇 |
预防医学 | 219篇 |
眼科学 | 122篇 |
药学 | 276篇 |
中国医学 | 8篇 |
肿瘤学 | 350篇 |
出版年
2022年 | 25篇 |
2021年 | 87篇 |
2020年 | 91篇 |
2019年 | 122篇 |
2018年 | 133篇 |
2017年 | 86篇 |
2016年 | 109篇 |
2015年 | 136篇 |
2014年 | 196篇 |
2013年 | 232篇 |
2012年 | 335篇 |
2011年 | 329篇 |
2010年 | 185篇 |
2009年 | 174篇 |
2008年 | 287篇 |
2007年 | 262篇 |
2006年 | 290篇 |
2005年 | 272篇 |
2004年 | 226篇 |
2003年 | 250篇 |
2002年 | 224篇 |
2001年 | 102篇 |
2000年 | 104篇 |
1999年 | 92篇 |
1998年 | 76篇 |
1997年 | 57篇 |
1996年 | 48篇 |
1995年 | 44篇 |
1994年 | 31篇 |
1993年 | 28篇 |
1992年 | 49篇 |
1991年 | 57篇 |
1990年 | 53篇 |
1989年 | 62篇 |
1988年 | 58篇 |
1987年 | 52篇 |
1986年 | 36篇 |
1985年 | 28篇 |
1984年 | 25篇 |
1983年 | 37篇 |
1982年 | 15篇 |
1981年 | 24篇 |
1980年 | 17篇 |
1979年 | 20篇 |
1978年 | 30篇 |
1977年 | 22篇 |
1976年 | 16篇 |
1975年 | 27篇 |
1973年 | 20篇 |
1968年 | 17篇 |
排序方式: 共有5411条查询结果,搜索用时 156 毫秒
81.
Roberto Maggio Fabio Fumagalli Eugenio Donati Pascaline Barbier Giorgio Racagni Giovanni U. Corsini Marco Riva 《Brain research》1995,679(1):184
We investigated whether the severity of convulsions evoked by kainic acid and pilocarpine is modified in nitric oxide synthase inhibitor-treated rats. We found that chronic treatment (4 days) withNw-nitro-l-arginine greatly potentiates seizures induced by both convulsants suggesting a potential role for nitric oxide in mechanisms regulating seizure induction and propagation. 相似文献
82.
83.
Age-related macular degeneration (AMD) is a common cause of legal blindness in the developed countries in people older than 50 years of age. AMD complicated by choroidal neovascular membranes (CNV) accounts for 12% of AMD, but for 88% of legal blindness cases. Because of the progressive aging of the population, it is expected that AMD will be one of the greater public health problems in ophthalmology in the first half of the next century. Laser photocoagulation remains the only proven treatment for CNV in AMD, but unfortunately, is applicable only to a minority of patients presenting with CNV in AMD. Photodynamic therapy (PDT) is a new experiment treatment for CNV that combines the application of low-intensity light with a photosensitizing agent in the presence of oxygen to produce tissue effects. It uses the noninvasive potential of the laser light to cause a nonthermal localized chemotoxic reaction and obtain highly selective occlusion of the neovascular channels, with sparing of the overlying photoreceptors. Animal studies showed that PDT accounts for the effective closure of experimentally induced CNV. Phase I-II clinical studies showed that PDT using BPD can safely stabilize leakage from CNV in a majority of patients for up to 3 months. Phase III clinical studies to assess the long term prognosis of PDT-treatment of CNV in AMD are ongoing. 相似文献
84.
Brett A. Trockman Jill Gerspach Roger Dmochowski Francois Haab Phillippe E. Zimmern Gary E. Leach 《The Journal of urology》1996,156(4):1418-1420
Purpose
We reviewed the urodynamic findings and treatment outcomes of a large series of men with primary bladder neck obstruction.Materials and Methods
A retrospective review was done of the presenting symptoms and urodynamic findings of 36 men with primary bladder neck obstruction. Outcomes after treatment with alpha-blockers, transurethral incision of the bladder neck and prostate, or no long-term therapy were determined by chart review and patient survey in the majority of cases.Results
Mean age of the men was 41 years. Patients had significant lower urinary tract symptoms, decreased peak urinary flow rates, elevated post-void residual, markedly elevated peak voiding pressures and poor funneling of the bladder neck during voiding. Although most patients initially chose alpha-blocker therapy, only 30 percent of those beginning alpha-blockers continued them long term, usually due to inadequate symptomatic improvement. A total of 18 men underwent transurethral incision, which resulted in significant improvements in symptom scores, peak urinary flow rates, post-void residual and peak voiding pressures. Patients reported a mean 87 percent overall improvement in symptoms after transurethral incision.Conclusions
Video urodynamics facilitate diagnosis of primary bladder neck obstruction. Transurethral incision is the most effective therapy for primary bladder neck obstruction. 相似文献85.
Chikwendu Ibebunjo Coimbatore B. Srikant François Donati 《Journal canadien d'anesthésie》1996,43(5):475-484
Purpose
Although differences in fibre composition, fibre size or acetylcholine receptor (AChR) density between muscles have often been proposed to explain the unequal sensitivities of muscles to muscle relaxant drugs, it is not clear whether or how these parameters differ among muscles or are related to one another. In this study, several muscles were examined to determine the composition and cross-sectional area (CSA) of types I and II fibres, the surface area of their motor endplates (ESA), and their AChR density.Methods
Biopsies from the thyroarytenoideus, cricoarytenoideus dorsalis, masseter, diaphragm, transversus abdominis, rectus abdominis, gastrocnemius and soleus muscles of goats were processed by muscle histochemistry and morphometry and the ESA:CSA ratio was computed. The number and density of AChRs per endplate were estimated by125I-α-bungarotoxin binding studies.Results
The mean type 1 fibre composition (range: 0–100%), fibre diameter (28–50 μm) and the ESA:CSA ratio (0.27–1.01) differed among muscles (P = 0.0001), but there were no significant differences (P > 0.05) in the mean endplate size (577–725 μm2), AChR number (6.6?14.5 × 106) or AChR density (8,900–22,300 μm?2) probably because of marked individual variations. Fibre size increased and the ESA:CSA ratio decreased in the order laryngeal, diaphragm, jaw, limb and abdominal muscles.Conclusion
It is concluded that between muscles fibre size varies more than endplate size or AChR number. 相似文献86.
G Bacci A Briccoli M Rocca S Ferrari D Donati A Longhi F Bertoni P Bacchini S Giacomini C Forni M Manfrini S Galletti 《Annals of oncology》2003,14(7):1126-1134
BACKGROUND: Effective adjuvant or neoadjuvant regimens of chemotherapy have dramatically improved the prognosis of patients with high-grade osteosarcoma of the extremity, localized at diagnosis. Currently, little is known about patients with metastatic disease at presentation. PATIENTS AND METHODS: From May 1995 to May 2000, 57 patients with osteosarcoma of the extremity, metastatic at presentation, were treated according to the following scheme: primary chemotherapy, restaging, simultaneous resection of primary tumor and metastatic lesions, and maintenance chemotherapy. RESULTS: Thirty-five patients achieved remission. At a follow-up ranging from 2 to 7 years, seven remained continuously free of disease, one died of chemotherapy-related toxicity and 27 patients relapsed. Twenty-one of the 22 patients who never achieved remission died as a result of the tumor, as well as 20 of the 27 who achieved remission but then relapsed. Of the remaining seven relapsing patients, six are alive with uncontrolled disease, while one is alive and free of disease 24 months after the last post-relapse treatment. Two-year event-free survival (EFS) and overall survival (OS) were 21% and 55%, respectively. These results are significantly poorer than those achieved in 128 contemporary patients with non-metastatic disease at presentation, treated with the same chemotherapy protocol (2-year EFS and OS of 75% and 94%, respectively). CONCLUSIONS: The results of our study confirm that the prognosis of patients with osteosarcoma of the extremity, metastatic at presentation, remains poor, despite the use of aggressive treatments. 相似文献
87.
Massive bone allograft reconstruction in high-grade osteosarcoma 总被引:18,自引:0,他引:18
Donati D Di Liddo M Zavatta M Manfrini M Bacci G Picci P Capanna R Mercuri M 《Clinical orthopaedics and related research》2000,(377):186-194
From 1986 to 1994, 112 bone allograft reconstructions were performed in patients with high-grade osteosarcoma in whom neoadjuvant chemotherapy was administered. The allograft reconstruction was used in arthrodesis in 44 cases (41 knees, three ankles), as an intercalary graft in 39 (28 femurs, 11 tibias), as an osteoarticular graft in 22 (three proximal and/or distal humeri, six distal femurs, 13 proximal tibias), and as an allograft and prosthesis composite in seven (two proximal humeri, one proximal femurs, four proximal tibias). In 20 patients an autologous vascularized fibula was used to augment the allograft. Functional results were excellent or good in 74% of the patients after the primary surgery, and in 83% of the patients after secondary surgery. Complications include delayed union (49%) and fracture (27%), although there were no cases of deep infection. The incidence of delayed union, but not infection or fracture, was increased by the use of chemotherapy. 相似文献
88.
Barbanti Bròdano G Donati U Palmisani M Pompili M Boriani S 《La Chirurgia degli Organi di Movimento》2000,85(4):345-360
It is the purpose of this study to evaluate the clinical and radiographic medium-term results of a series of 60 patients submitted to intersomatic lumbar fusion by posterior approach, using a system constituted by carbon wedges to be associated with bone grafts for intersomatic fusion, and by steel or titanium plates or bars used for posterior pedicle osteosynthesis. Satisfactory clinical results were obtained in 88.2% of cases and complete radiographic fusion in 91.4% of cases. Complications were generally observed in 8.3% of cases. In light of these results, we may consider intersomatic lumbar fusion by posterior approach a method that is perhaps aggressive, but effective in the treatment of severe lumbar spondylolysis. The use of carbon wedges brings several advantages that favor intersomatic fusion, its progressive control, and the restoration of normal lordosis of the lumbar spine. 相似文献
89.
Effect of recombinant interleukin-2 pretreatment on oral and intravenous digoxin pharmacokinetics and P-glycoprotein activity in mice. 总被引:1,自引:0,他引:1
Vincent Castagne Laurence Bonhomme-Faivre Saik Urien Makram Ben Reguiga Mireille Soursac Francois Gimenez Robert Farinotti 《Drug metabolism and disposition》2004,32(2):168-171
P-glycoprotein (P-gp) is an ATP-dependent efflux membrane transporter involved in many drug pharmacokinetics in humans. Decreasing its expression could enhance the bioavailability of substrates as digoxin. We have recently found that human recombinant interleukin-2 (rIL2) in vivo decreases P-gp expression in intestine and brain of mice and modifies oral digoxin pharmacokinetics. The aim of the study was to evaluate the involvement of bioavailability in the rIL2 pretreatment effect on digoxin pharmacokinetics by comparing oral and i.v. digoxin pharmacokinetics before and after rIL2 pretreatment (10 microg/kg). We also tried to show the possible effect of a low rIL2 dose (1 microg/kg) pretreatment on oral digoxin pharmacokinetics. First, adult Swiss mice received a single oral or i.v. dose of digoxin (0.03 mg/kg). Two weeks later, the same animals were treated by rIL2 i.p. twice a day (10 microg/kg) for 4 days and received digoxin again at day 5. As well, another group received oral digoxin (0.03 mg/kg) with a 1 microg/kg rIL2 pretreatment. Blood was collected after digoxin administration with and without rIL2 pretreatment. Digoxin pharmacokinetics were described by a one-compartment model. The 10 microg/kg rIL2 pretreatment did not modify i.v. digoxin pharmacokinetics, whereas oral digoxin pharmacokinetics were significantly modified by the 10 microg/kg rIL2 pretreatment and not by the 1 microg/kg rIL2 pretreatment. The decrease of P-gp activity, caused by rIL2 (10 microg/kg), increased digoxin bioavailability. An increase in exposure and intracellular level of drugs is expected from rIL2 pretreatment. 相似文献
90.
Filip Kiekens Ann Debunne Chris Vervaet Lieven Baert Filip Vanhoutte Ivo Van Assche Francois Menard Jean Paul Remon 《European journal of pharmaceutical sciences》2004,22(2-3):117-126
The volume reduction behaviour of powders has been quantified by means of the 'in-die' yield pressure (YP) using Heckel analysis. However, because different YPs are reported for the same material, the experimental conditions influencing this material-constant were investigated. Silicified microcrystalline cellulose was compressed into flat-faced and convex tablets using a compaction simulator instrumented with load and displacement transducers. During compression, upper and lower punch force and displacement data were recorded and corrected for punch deformation. A symmetrical triangle wave compression profile was used and the instantaneous punch velocity was kept constant (5mm/s). Individual tablet height and weight were used for Heckel analysis. The influence of the 'effective compression pressure' (P(EFF)) (ranging from 10 to 350 MPa), punch diameter (PD) (4, 9.5 and 12 mm) and filling depth (FD) (4.5, 7.5 and 10.5mm) on YP was statistically evaluated using Response Surface Modelling software. A quadratic surface response equation, describing the relationship between P(EFF), PD, FD and YP, was proposed for concave (Adj R(2): 0.8424; S.D.: 14.60 MPa) and flat-faced (Adj R(2): 0.8409; S.D.: 4.49 MPa) punches. YP and tensile strength were mainly determined by P(EFF), irrespective of punch curvature. FD and PD had only a minor influence on the YP, although more pronounced for the concave punches. The method used resulted in reproducible P(EFF) and tensile strength values and the flat-faced tablets showed less weight variation. Flat-faced punches are preferred over punches with a concave surface when investigating the volume reduction behaviour of a powder by means of Heckel analysis and the experimental parameters should be reported. 相似文献