全文获取类型
收费全文 | 7811篇 |
免费 | 554篇 |
国内免费 | 51篇 |
专业分类
耳鼻咽喉 | 50篇 |
儿科学 | 312篇 |
妇产科学 | 126篇 |
基础医学 | 957篇 |
口腔科学 | 89篇 |
临床医学 | 743篇 |
内科学 | 1656篇 |
皮肤病学 | 106篇 |
神经病学 | 844篇 |
特种医学 | 353篇 |
外科学 | 1237篇 |
综合类 | 35篇 |
预防医学 | 532篇 |
眼科学 | 132篇 |
药学 | 572篇 |
中国医学 | 14篇 |
肿瘤学 | 658篇 |
出版年
2024年 | 14篇 |
2023年 | 96篇 |
2022年 | 121篇 |
2021年 | 202篇 |
2020年 | 172篇 |
2019年 | 218篇 |
2018年 | 266篇 |
2017年 | 241篇 |
2016年 | 220篇 |
2015年 | 264篇 |
2014年 | 334篇 |
2013年 | 433篇 |
2012年 | 609篇 |
2011年 | 630篇 |
2010年 | 323篇 |
2009年 | 292篇 |
2008年 | 493篇 |
2007年 | 502篇 |
2006年 | 509篇 |
2005年 | 416篇 |
2004年 | 416篇 |
2003年 | 374篇 |
2002年 | 372篇 |
2001年 | 51篇 |
2000年 | 39篇 |
1999年 | 58篇 |
1998年 | 72篇 |
1997年 | 58篇 |
1996年 | 57篇 |
1995年 | 51篇 |
1994年 | 43篇 |
1993年 | 47篇 |
1992年 | 29篇 |
1991年 | 25篇 |
1990年 | 23篇 |
1989年 | 24篇 |
1988年 | 20篇 |
1987年 | 24篇 |
1986年 | 24篇 |
1985年 | 24篇 |
1984年 | 20篇 |
1983年 | 34篇 |
1982年 | 19篇 |
1981年 | 22篇 |
1980年 | 13篇 |
1979年 | 15篇 |
1978年 | 10篇 |
1975年 | 14篇 |
1972年 | 7篇 |
1967年 | 7篇 |
排序方式: 共有8416条查询结果,搜索用时 0 毫秒
61.
Background
Hip dislocation in children with cerebral palsy (CP) is a common and severe problem. The dislocation can be avoided, by screening and preventive treatment of children with hips at risk. The aim of this study was to analyse the characteristics of children with CP who develop hip displacement, in order to optimise a hip surveillance programme. 相似文献62.
Anti-LFA-1 improves pig islet xenograft function in diabetic mice when long-term acceptance is induced by CTLA4Ig/anti-CD40L 总被引:1,自引:0,他引:1
Kumagai-Braesch M Ekberg H Wang F Osterholm C Ehrnfelt C Sharma A Lindeborg E Holgersson J Corbascio M 《Transplantation》2007,83(9):1259-1267
BACKGROUND: It has been previously demonstrated that addition of anti-LFA-1 to a combination of CTLA4Ig and anti-CD40L induces the permanent acceptance of dopaminergic fetal pig xenografts when transplanted into the brain of wild-type mice. The purpose of this study was to test whether this costimulation blockade also can induce acceptance of adult pig islets transplanted to C57BL/6 mice with streptozotocin-induced diabetes. METHODS: Recipients were treated with CTLA4Ig/anti-CD40L+/-anti-LFA-1 or isotype control antibodies during the first week after transplantation. Half of the costimulation blockade-treated recipients had their grafts removed after 8 weeks. The other half was observed up to 5 months. RESULTS: Recipients treated with CTLA4Ig/anti-CD40L/anti-LFA-1 had significantly lower blood glucose and gained more weight than CTLA4Ig/anti-CD40L-treated recipients. CTLA4Ig/anti-CD40L-treated recipients exhibited unstable blood glucose. IPGTT of these recipients revealed a slow recovery to normal blood glucose levels at week 4. In comparison, CTLA4Ig/anti-CD40L/anti-LFA-1 treated recipients exhibited a significantly superior glucose clearance. CTLA4Ig/anti-CD40L+/-anti-LFA-1 treated recipients did not produce anti-pig IgG, whereas control antibody-treated mice did. CD4+ T cells from costimulation blockade-treated recipients proliferated less than CD4+ T cells from control antibody-treated mice when co-cultured with syngeneic antigen presenting cells loaded with pig islet antigens. CONCLUSIONS: CTLA4Ig/anti-CD40L/anti-LFA-1-treated recipients had superior islet function compared with CTLA4Ig/anti-CD40L-treated recipients. However, both costimulation blockade regimens led to islet graft acceptance up to 5 months after a 1-week treatment. 相似文献
63.
Palm H Jacobsen S Sonne-Holm S Gebuhr P;Hip Fracture Study Group 《The Journal of bone and joint surgery. American volume》2007,89(3):470-475
BACKGROUND: Reoperations after intertrochanteric fractures are often necessitated by fracture displacement following mobilization of the patient. The biomechanical complexity of the fracture, the position of the implant, and the patient's characteristics are known to influence postoperative outcome. We investigated the importance of an intact lateral femoral wall as a factor in postoperative fracture displacement after fixation with a sliding compression hip screw. METHODS: Two hundred and fourteen consecutive patients with an intertrochanteric fracture were treated with a 135 degrees sliding compression hip screw with a four-hole side-plate between 2002 and 2004. The fractures were classified on preoperative radiographs according to the AO/OTA classification system. The status of the greater and lesser trochanters, the integrity of the lateral femoral wall, and the position of the implant were assessed postoperatively. Reoperations due to technical failure were recorded for six months postoperatively. RESULTS: Only 3% (five) of 168 patients with an intact lateral femoral wall postoperatively underwent a reoperation within six months, whereas 22% (ten) of forty-six patients with a fractured lateral femoral wall were operated on again (p < 0.001). Multivariate logistic regression analyses combining demographic and biomechanical parameters showed a compromised lateral femoral wall to be a significant predictor of a reoperation (p = 0.010). Seventy-four percent (thirty-four) of the forty-six fractures of the lateral femoral wall occurred during the operative procedure itself. A fracture of the lateral femoral wall occurred in only 3% (three) of the 103 patients with an AO/OTA type-31-A1.1, A1.2, A1.3, or A2.1 intertrochanteric fracture compared with 31% (thirty-one) of the ninety-nine with an AO/OTA type 31-A2.2 or A2.3 fracture (p < 0.001). CONCLUSIONS: A postoperative fracture of the lateral femoral wall was found to be the main predictor for a reoperation after an intertrochanteric fracture. Consequently, we concluded that patients with preoperative or intraoperative fracture of the lateral femoral wall are not treated adequately with a sliding compression hip-screw device, and intertrochanteric fractures should therefore be classified according to the integrity of the lateral femoral wall, especially in randomized trials comparing fracture implants. 相似文献
64.
65.
Ho-Rim Choi John Siliski Henrik Malchau Andrew Freiberg Harry Rubash Young-Min Kwon 《International orthopaedics》2014,38(8):1641-1645
Purpose
To evaluate how often manipulation under anesthesia (MUA) can achieve functional flexion ≥ 90 degrees and identify predictor for successful outcome of MUA for stiff total knee arthroplasty (TKA).Methods
Demographic data, range of motion, and surgical and anesthetic information of 143 MUAs were retrospectively analyzed from 2000 to 2011.Results
One-hundred thirty-six out of 143 patients (95 %) improved mean range of motion (ROM) from pre-MUA 62 ± 17° to final ROM 101 ± 21° (p < 0.001). Flexion ≥ 90 degrees was achieved in 74% (106/143) of patients. Regional anesthesia was identified as predictor of successful MUA outcome (p = 0.007, OR: 8.5, 95 % CI: 1.2-66.7).Conclusions
Although the proportion of patients regaining flexion ≥ 90 degrees following MUA was less than those patients with simple overall ROM increase, the functional flexion ≥ 90 degrees was achieved in the vast majority of patients with stiff TKA following MUA. 相似文献66.
Christian Medom Madsen Henrik Løvendahl Jørgensen Astrid Norgaard Troels Riis Christopher Jantzen Ole Birger Pedersen Benn Rønnow Duus Jes Bruun Lauritzen 《Archives of orthopaedic and trauma surgery》2014,134(3):375-382
Introduction
Red blood cell (RBC) transfusion is a frequently used treatment in patients admitted with a fractured hip, but the use remains an area of much debate. The aim of this study was to determine preoperative factors associated with the risk of receiving a red blood cell transfusion in hip fracture patients.Method
The study included 986 consecutive hip fracture patients (aged 60 years or above). The patients were identified from a database of all hip fracture patients admitted to Bispebjerg University Hospital. Data for the database are collected via chart review and data extraction from the hospitals laboratory system, public registries and from the Capital Region Blood Bank Database.Results
Overall transfusion rate was 58.7 %. The univariate analyses showed that transfusion rate was higher among women (p = 0.004), older patients (p < 0.0001), patients with high ASA scores (p < 0.0001), patients with more severe fractures (p < 0.0001), patients with lower admission haemoglobin levels (p < 0.0001), patients not admitted from own home (p = 0.02) and patients taking aspirin (p = 0.007) or other platelet inhibitors (p = 0.01) on admission. In the multivariate analysis, increasing age, ASA ≥3, being admitted from own home, extracapsular fractures, decreasing admission haemoglobin and use of platelet inhibitors were all significantly associated with the risk of receiving a RBC transfusion.Conclusion
Several readily available preoperative factors in the form of age, residence, ASA, admission haemoglobin, medication and type of fracture were independently associated with the likelihood of receiving a red blood cell transfusion in patients admitted with a fractured hip. 相似文献67.
Michael Maeng Henrik Mertz Søren Nielsen Guillaume van Eys Klaus Rasmussen Geert Espersen 《Scandinavian cardiovascular journal : SCJ》2013,47(1):34-42
AbstractObjective—Myofibroblasts migrating from adventitia have been suggested to constitute a majority of neointimal cells after angioplasty. We sought to examine this hypothesis by use of smoothelin, which is a marker for the quiescent smooth muscle cell (SMC) phenotype while not expressed by myofibroblasts. Design—Balloon angioplasty was performed in left iliac arteries of 25 rabbits that were killed after 3-56 days. Arterial cross-sections were immunostained for (X-actin (general marker), smoothelin (quiescent SMC phenotype), and Ki-67 (proliferative phenotype).Results—Adventitial cells became transiently actinpositive (myofibroblasts) but did not express smoothelin at any time point. In media, angioplasty induced transient proliferation and coinciding transient decrease in smoothelin expression. Neointimal cells, present 7 days after angioplasty, were initially proliferating and smoothelin-negative but changed to non-proliferating, smoothelin-positive cells after 56 days where 82 ± 10% of cells stained positive for smoothelin. This phenotypic modulation of medial and intimal cells began in media and moved gradually towards the lumen.Conclusion—At late follow-up, the majority of intimal cells are smoothelin-positive indicating that adventitial myofibroblasts play no major role for neointima formation. 相似文献
68.
Introduction Uncemented stems in total hip arthroplasty (THA) are used increasingly often because they are believed to offer a reliable long-term fixation. However, periprosthetic bone remodelling has been a worrying issue. A proximal demineralization has been noted in femurs with well-fixed stems, and it has been explained as by-passing of mechanical forces along the fixed implant (stress-shielding). Aseptic loosening has been a major problem in several uncemented series with earlier designs. The objective for this study was to investigate how the host bone adapts to a loose stem compared with a well-fixed stem after a long time.Materials and methods An investigation with dual-energy X-ray absorptiometry (DEXA), scintimetry and radiological assessment was carried out in 20 patients 8 years after a THA for arthrosis with two different uncemented stems. Ten patients received a stem coated with polytetrafluoroethylene (Anaform); all prostheses showed migration and were considered unstable. Ten patients received a hydroxyapatite-coated stem (Bi-Metric); no prosthesis migrated.Results Different remodelling patterns were seen. In the unstable group, the periprosthetic bone mineral density (BMD) was significantly reduced along the entire stem, while in the stable group only proximal bone loss was seen. The scintigraphic uptake was increased under the stem tip in both groups, and among unstable stems uptake was also increased in the calcar region.Conclusion The assessment of periprosthetic bone remodelling after uncemented THA with long-term observation shows a different host-bone response in stable versus unstable femoral implants. Prior to a femoral revision, measurement of the BMD could be beneficial; it may guide the surgeon when deciding which surgical technique to use. 相似文献
69.
Introduction
In laparoscopic colorectal cancer surgery, some authors still report increased conversion rates, operative duration and postoperative morbidity with longer hospital stay in obese patients. In our department, we had the impression that laparoscopic surgery in the obese was feasible and safe, leading to this study in which we evaluate laparoscopic surgery for colorectal cancers in the obese and measure the impact on short-term results.Material and Methods
In the period from November 2004 to May 2010, 425 patients were laparoscopically operated for a colon or rectal cancer in our center. Ninety-three patients had a body mass index (BMI)????30. Demographic data and short-term outcome in patients with a BMI????30 were compared to the same data in patients with a BMI?<?30.Results
The median operative time was significantly longer (240 vs. 225?min, p?=?0.021) and the mean blood loss was significantly higher (348 vs. 285?ml, p?=?0.034) in the group of patients with BMI????30. No other significant differences, including conversion to open surgery and postoperative morbidity, were found between the two groups.Conclusion
Laparoscopic colorectal cancer surgery is feasible and safe in obese patients with a BMI above 30, without the patients experiencing an increased risk of postoperative morbidity or mortality. 相似文献70.
Neuhaus J Schulte-Baukloh H Stolzenburg JU Speroni di Fenizio P Horn LC Rüffert H Hartenstein S Burger M Schulze M Schwalenberg T 《World journal of urology》2012,30(5):693-700