全文获取类型
收费全文 | 22622篇 |
免费 | 1307篇 |
国内免费 | 539篇 |
专业分类
耳鼻咽喉 | 113篇 |
儿科学 | 288篇 |
妇产科学 | 462篇 |
基础医学 | 1919篇 |
口腔科学 | 604篇 |
临床医学 | 2873篇 |
内科学 | 3740篇 |
皮肤病学 | 133篇 |
神经病学 | 446篇 |
特种医学 | 703篇 |
外科学 | 6833篇 |
综合类 | 2948篇 |
预防医学 | 974篇 |
眼科学 | 207篇 |
药学 | 1457篇 |
19篇 | |
中国医学 | 347篇 |
肿瘤学 | 402篇 |
出版年
2024年 | 42篇 |
2023年 | 561篇 |
2022年 | 985篇 |
2021年 | 1424篇 |
2020年 | 1379篇 |
2019年 | 1120篇 |
2018年 | 1006篇 |
2017年 | 726篇 |
2016年 | 690篇 |
2015年 | 693篇 |
2014年 | 1610篇 |
2013年 | 1638篇 |
2012年 | 1160篇 |
2011年 | 1308篇 |
2010年 | 1071篇 |
2009年 | 1047篇 |
2008年 | 985篇 |
2007年 | 892篇 |
2006年 | 855篇 |
2005年 | 754篇 |
2004年 | 688篇 |
2003年 | 575篇 |
2002年 | 484篇 |
2001年 | 359篇 |
2000年 | 326篇 |
1999年 | 246篇 |
1998年 | 227篇 |
1997年 | 192篇 |
1996年 | 170篇 |
1995年 | 164篇 |
1994年 | 147篇 |
1993年 | 115篇 |
1992年 | 117篇 |
1991年 | 56篇 |
1990年 | 73篇 |
1989年 | 61篇 |
1988年 | 70篇 |
1987年 | 84篇 |
1986年 | 56篇 |
1985年 | 52篇 |
1984年 | 45篇 |
1983年 | 33篇 |
1982年 | 34篇 |
1981年 | 29篇 |
1980年 | 27篇 |
1979年 | 24篇 |
1978年 | 14篇 |
1977年 | 13篇 |
1976年 | 12篇 |
1975年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
《Revista espa?ola de anestesiología y reanimación》2022,69(9):517-525
Background and objectivesThe ideal timing of tranexamic acid administration in total knee arthroplasty with tourniquet remains unclear. Our primary objective was to prove if administering it before surgical incision, instead of before releasing the tourniquet, reduces postoperative bleeding. A second objective was to determine whether a second dose reduces post-operative bleeding.Material and methodsA prospective, double-blind clinical trial was performed on 212 patients scheduled for total knee arthroplasty. They were randomised into 4 groups. Tranexamic acid was administered before the surgical incision in “pre-induction groups” (1 and 2), and just before the tourniquet release in “pre-release groups” (3 and 4). Groups 2 and 4 received a second dose 3 hours post-surgery. Main outcome was postoperative bleeding (visible blood loss and calculated total bleeding). Secondary outcomes were haemoglobin variations, complications and transfusion rate.ResultsThe mean calculated total bleeding was 1563 ml (95%CI: 1445 to 1681) in preinduction groups versus 1576 ml (95%CI: 1439 to 1713) in pre-release groups (P = .9); 1579 ml (95%CI: 1452 to 1706) in single-dose groups versus 1559 ml (95%CI: 1431 to 1686) in double-dose groups (P = .82). One patient was transfused. The mean haemoglobin at discharge was 10.4 g/dl (95%CI: 10.2 to 10.7) in singledose groups versus 10.8 (95%CI: 10.6 to 11.1) in double-dose groups (P = .06).ConclusionsThere were no differences in bleeding or transfusion regarding the time of tranexamic acid administration. The second dose had not impact on outcomes.Trial registration: EudraCT 2016-000071-24. 相似文献
32.
33.
34.
Brenda Laky Isabella Alram Julia K. Frank Leo Pauzenberger Werner Anderl Karl-Heinz Wagner Philipp R. Heuberer 《Journal of orthopaedic research》2020,38(9):2074-2082
Increasing numbers of arthroplasties are also accompanied by postoperative infections. The main purpose was to evaluate preoperative serum bilirubin levels between patients with and without infections after shoulder and knee arthroplasties. For this retrospective case-control single-center study, a total of 108 patients were extracted from a prospectively collected database. Eighteen patients with infections after shoulder (n = 8) and knee (n = 10) arthroplasty were matched by age, gender, and implant type in a 1:5-scenario to 90 patients (40 shoulders and 50 knees) without postoperative infection. Demographic data, preoperative blood parameters, and postoperative infection-related outcomes were evaluated. Total bilirubin was the only preoperative parameter significantly different between the infection (8.21 ± 3.25 μmol/L or 0.48 ± 0.19 mg/dL) and noninfection (10.78 ± 4.62 μmol/L or 0.63 ± 0.27 mg/dL; P = .014) group, while C-reactive protein and other liver parameters were similar between the groups. Significantly more controls (92.1%) had preoperative bilirubin levels above 8.72 μmol/L or 0.51 mg/dL than cases (7.9%; P = .007). The 5-year infection survival-rate was 65.6% for patients with preoperative bilirubin levels < 8.72 μmol/L or < 0.51 mg/dL and 91.2% with ≥ 8.72 μmol/L or ≥ 0.51 mg/dL. Mildly decreased preoperative bilirubin levels with a cutoff at 8.72 μmol/L or 0.51 mg/dL were significantly associated to patients with infections after shoulder and knee arthroplasty. There were no differences in other blood parameters or comorbidities between patients with infections and their matched-controls. 相似文献
35.
Giada Lullini Eugenio Cammisa Stefania Setti Iacopo Sassoli Stefano Zaffagnini Giulio Maria Marcheggiani Muccioli 《World journal of orthopedics》2020,11(6):285-293
Although the rate of patients reporting satisfaction is generally high after joint replacement surgery, up to 23% after total hip replacement and 34% after total knee arthroplasty of treated subjects report discomfort or pain 1 year after surgery. Moreover, chronic or subacute inflammation is reported in some cases even a long time after surgery. Another open and debated issue in prosthetic surgery is implant survivorship, especially when related to good prosthesis bone ingrowth. Pulsed Electro Magnetic Fields(PEMFs) treatment, although initially recommended after total joint replacement to promote bone ingrowth and to reduce inflammation and pain, is not currently part of usual clinical practice. The purpose of this review was to analyze existing literature on PEMFs effects in joint replacement surgery and to report results of clinical studies and current indications. We selected all currently available prospective studies or RCT on the use of PEMFs in total joint replacement with the purpose of investigating effects of PEMFs on recovery, pain relief and patients' satisfaction following hip, knee or shoulder arthroplasty. All the studies analyzed reported no adverse effects, and good patient compliance to the treatment. The available literature shows that early control of joint inflammation process in the first days after surgery through the use of PEMFs should be considered an effective completion of the surgical procedure to improve the patient's functional recovery. 相似文献
36.
BackgroundArtificial insemination with the husband’s semen (AIH) is an economical and noninvasive method of infertility treatment. However, AIH’s pregnancy rate is much lower than in vitro fertilization (IVF) as its multiple and complex uncertainty factors. Semen quality has been one of the main factors which affect the pregnancy outcome of AIH.MethodsThe relevant parameters of 1,142 AIH cycles were retrospectively studied, including the general parameters and the semen quality parameters among clinical pregnancy, biochemical pregnancy, non-pregnancy group, age, infertility duration, infertility type, body mass index (BMI), cycle count, morphology in previously semen examination, and semen quality parameters on the day of AIH.ResultsThe statistically significant difference was only found on processed total non-forward and non-motile sperm count (N-TFMSC). The mean processed N-TFMSC in the biochemical pregnancy group was 6.37±4.27 million, significantly higher than the other two groups (vs. 4.40±3.15 million or vs. 4.48±3.60 million, P<0.05). The study was then divided into two groups according to processed N-TFMSC, Group 1 ≤5.0 million, and Group 2 >5.0 million. A statistical increase in biochemical pregnancy rate was observed when the processed N-TFMSC was >5.0 million (2.72% vs. 0.90%).ConclusionsProcessed N-TFMSC may be one of the independent factors on AIH’s outcome; it should be given equal attention the same as processed total forward motile sperm count (TFMSC). 相似文献
37.
Bone stock preservation is crucial when performing total hip replacement in young patients. The aim is to save good bone stock
for a possible revision procedure. Furthermore, there is an increasing demand from young and active patients to receive a
new joint which allows a normal or nearly normal life style. With this in mind, we began, in 1993, to develop a new femoral
implant. The purpose of this ultra-short stem was a physiologic strain distribution on the proximal femur with a proximal
load transfer from the implant to the femoral bone. Main features were an almost complete absence of the diaphyseal portion
of the stem, a well defined lateral flare with load transfer on the lateral column of the femur, and a very high femoral neck
cut. These innovations resulted in a conservative implant on both the bone stock and the soft tissues. This implant, in the
first years, was recommended only for young and active patients. Over the last thirteen years, this project has undergone
several modifications but the basic principles of the implant have remained the same. In the present review, we present the
rationale, the surgical technique and the clinical and experimental results so far obtained with this implant. 相似文献
38.
Objective To investigate the clinical effects of total hip arthroplasty (THA) for bony ankylosis in patients with ankylosing spondylitis and the significance of postoperative rehabilitation. Meth-ods From October 1998 to May 2007, 28 patients (46 hips) suffered from ankylosing spondylitis with hip bony ankylosis underwent THA. There were 27 males, 1 female, with the mean age of 38.9 years (range 22 to 58 years). Posterior lateral hip incision was performed in 34 hips, and modified anterior lateral combined with lateral hip incision in 12 hips. Forty hips applied cementless THA and 6 hips applied mixed THA. Har-ris scores, VAS scores and total hip range of motion in all patients were compared pre-and postoperatively to evaluate the clinical effects. Results All patients were followed up from 10 months to 64 months, with the mean time of 38.2 months. No paralysis, decubitus, and lung infection were found. Joint dislocation hap-pened in 1 case 2 weeks after operation, and was cured with close reduction. Heterotopic bone formation with Brooker Ⅰ was found in 6 hips and Brooker Ⅱ in 2 hips. Harris score increased from 28.3±10.3 preop-eratively to 82.7±7.6 postoperatively. VAS score changed from 3.5±1.4 preoperatively to 3.8±1.8 postopera-tively, and no significance was found. The hip movement range increased from 15.6°±9.3° preoperatively to 133.7°±17.6° postoperatively. Bony ankylosis in all patients disappeared and the hip function improved sig-nificantly after operation. Conclusion THA is the optimal method to treat the ankylosing spondylitis with hip bony ankylosis. Early rehabilitation is necessary to improve hip function. 相似文献
39.
目的:分析钛-瓷修复体失败的原因。方法:对38例瓷裂的钛-瓷修复体进行分析:①肉眼观察烤瓷崩瓷部铸件的表面颜色并用便携式厚度测试仪测量其厚度,与未发生瓷裂的正常镰铬合金烤瓷比较;②观察烤瓷崩瓷的部位;③X-ray检测铸件内部气孔。结果:本组崩瓷的钛-瓷修复体,其断层或有气泡,或金属表面氧化层明显增厚(P〈0.05)。而且,所有发生崩瓷的部位均在受力点或因技工本身操作不当引起。结论:钛-瓷修复体失败的原因与加工过程中工艺、瓷的受力点以及与钛元素化学性能有关。 相似文献
40.
Early micromotion of implant components and periprosthetic bone loss in patients undergoing total knee arthroplasty are thought
to contribute to late aseptic loosening. In the pursuit of longer implant survival, the administration of bisphosphonates
may be advocated as a means to buffer implants against microinstability and periprosthetic bone loss. A bibliographic search
identified one metaanalysis and two randomised controlled trials dealing with this topic. Current evidence supports the hypothesis
that the inhibiting effects of bisphosphonates on bone resorption reduce implant micromotion and periprosthetic bone loss
at the one-year follow-up. Tested bisphosphonates include clodronate, pamidronate and alendronate. However, a decline in periprosthetic
BMD is observed at the three-year follow-up following a sixmonth course of bisphosphonate administration. Length of follow-up
in available studies is currently too short to determine whether bisphosphonates increase the longevity of implants. Furthermore,
the optimal dose, modality and length of bisphosphonate administration have yet to be determined. 相似文献