首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1617篇
  免费   102篇
  国内免费   4篇
耳鼻咽喉   65篇
儿科学   48篇
妇产科学   14篇
基础医学   163篇
口腔科学   36篇
临床医学   119篇
内科学   260篇
皮肤病学   31篇
神经病学   93篇
特种医学   33篇
外科学   460篇
综合类   34篇
预防医学   79篇
眼科学   47篇
药学   121篇
中国医学   5篇
肿瘤学   115篇
  2023年   9篇
  2022年   30篇
  2021年   60篇
  2020年   25篇
  2019年   49篇
  2018年   59篇
  2017年   41篇
  2016年   34篇
  2015年   37篇
  2014年   52篇
  2013年   55篇
  2012年   107篇
  2011年   129篇
  2010年   65篇
  2009年   61篇
  2008年   94篇
  2007年   91篇
  2006年   121篇
  2005年   92篇
  2004年   78篇
  2003年   68篇
  2002年   79篇
  2001年   40篇
  2000年   51篇
  1999年   30篇
  1998年   20篇
  1997年   12篇
  1996年   9篇
  1995年   7篇
  1994年   7篇
  1993年   4篇
  1992年   8篇
  1991年   12篇
  1990年   13篇
  1989年   11篇
  1988年   7篇
  1987年   4篇
  1986年   2篇
  1985年   5篇
  1984年   5篇
  1983年   5篇
  1982年   2篇
  1981年   7篇
  1979年   4篇
  1978年   3篇
  1973年   2篇
  1966年   2篇
  1957年   2篇
  1933年   1篇
  1929年   1篇
排序方式: 共有1723条查询结果,搜索用时 13 毫秒
11.
High-risk combinations of recipient and graft characteristics are poorly defined for liver retransplantation (reLT) in the current era. We aimed to develop a risk model for survival after reLT using data from the European Liver Transplantation Registry, followed by internal and external validation. From 2006 to 2016, 85 067 liver transplants were recorded, including 5581 reLTs (6.6%). The final model included seven predictors of graft survival: recipient age, model for end-stage liver disease score, indication for reLT, recipient hospitalization, time between primary liver transplantation and reLT, donor age, and cold ischemia time. By assigning points to each variable in proportion to their hazard ratio, a simplified risk score was created ranging 0–10. Low-risk (0–3), medium-risk (4–5), and high-risk (6–10) groups were identified with significantly different 5-year survival rates ranging 56.9% (95% CI 52.8–60.7%), 46.3% (95% CI 41.1–51.4%), and 32.1% (95% CI 23.5–41.0%), respectively (< 0.001). External validation showed that the expected survival rates were closely aligned with the observed mortality probabilities. The Retransplantation Risk Score identifies high-risk combinations of recipient- and graft-related factors prognostic for long-term graft survival after reLT. This tool may serve as a guidance for clinical decision-making on liver acceptance for reLT.  相似文献   
12.
Full-left-full-right split liver transplantation (FSLT) for adult recipients, may increase the availability of liver grafts, reduce waitlist time, and benefit recipients with below-average body weight. However, FSLT may lead to impaired graft and patient survival. This study aims to assess outcomes after FSLT. Five databases were searched to identify studies concerning FSLT. Incidences of complications, graft- and patient survival were assessed. Discrete data were pooled with random-effect models. Graft and patient survival after FSLT were compared with whole liver transplantation (WLT) according to the inverse variance method. Vascular complications were reported in 25/273 patients after FSLT (Pooled proportion: 6.9%, 95%CI: 3.1–10.7%, I2: 36%). Biliary complications were reported in 84/308 patients after FSLT (Pooled proportion: 25.6%, 95%CI: 19–32%, I2: 44%). Pooled proportions of graft and patient survival after 3 years follow-up were 72.8% (95%CI: 67.2–78.5, = 231) and 77.3% (95%CI: 66.7–85.8, = 331), respectively. Compared with WLT, FSLT was associated with increased graft loss (pooled HR: 2.12, 95%CI: 1.24–3.61, = 0.006, = 189) and patient mortality (pooled HR: 1.81, 95%CI: 1.17–2.81, = 0.008, = 289). FSLT was associated with high incidences of vascular and biliary complications. Nevertheless, long-term patient and graft survival appear acceptable and justify transplant benefit in selected patients.  相似文献   
13.
Annals of Surgical Oncology - The liver-first approach in patients with synchronous colorectal liver metastases (CRLM) has gained wide consensus but its role is still to be clarified. We aimed to...  相似文献   
14.
15.
16.
A high-pressure liquid chromatographic method for determination of the bisdioxopiperazine derivative ADR-529 (ICRF-187), a compound proven effective in protection against anthracycline-induced cardiotoxicity, has been developed. The limit of quantitation was 5 ng/ml using a narrow-bore 5-m silica column and UV detection. The method was used for determination of pharmacokinetic profiles of ADR-529 after a 3-weekly i.v. administration of different doses of ADR-529 (600–1000 mg/m2) together with different doses of epirubicin (E, 60–100 mg/m2), fixed-dose cyclophosphamide (C, 600 mg/m2), fixed-dose 5-fluorouracil (F, 600 mg/m2), and daily administration of tamoxifen (T, 30 mg; CEF-T) in the treatment of patients with metastatic breast cancer. Pharmacokinetic parameters for epirubicin were also determined. The aim of the study was to determine (1) whether the pharmacokinetics of ADR-529 as part of a combination with CEF-T changes with increasing doses of ADR-529 and increasing doses of epirubicin and (2) whether the pharmacokinetics of epirubicin in the same combinations is altered with the administration of increasing doses of ADR-529. A total of 82 patients were included. A crossover study including 16 of the patients showed no significant difference in epirubicin pharmacokinetic parameters when epirubicin was given with or without concomitant administration of ADR-529. Apart from minor changes in the distributional half-lives, the pharmacokinetic parameters of epirubicin were not altered with increasing doses of ADR-529, nor were the pharmacokinetic parameters of ADR-529 itself. Escalating doses of epirubicin did not significantly alter the pharmacokinetic parameters of ADR-529 with the exception of a 30% increase in the terminal half-life and a decrease in total body clearance when the epirubicin dose was raised from 60 to 100 mg/m2. We conclude that concomitant administration of ADR-529 does not alter the distribution and elimination of epirubicin in doses suitable for preventing the anthracycline-induced cardiotoxicity.  相似文献   
17.
18.
Carter JW  Mirza SK  Tencer AF  Ching RP 《Spine》2000,25(1):46-54
STUDY DESIGN: A laboratory study using isolated ligamentous human cadaveric cervical spines to investigate canal occlusion during (transient) and after (steady-state) axial compressive fracture. OBJECTIVES: To determine whether differences exist between transient and postinjury canal occlusion under axial compressive loading, and to examine the effect of loading rate on canal occlusion. SUMMARY OF BACKGROUND DATA: Prior studies have shown no correlation between neurologic deficit and canal occlusion measurements made on radiographs and computed tomography scans. The authors hypothesized that postinjury radiographic assessment does not provide an appreciation for the transient occlusion that occurs during the traumatic fracture event, which may significantly affect the neurologic outcome. METHODS: Twelve human cervical spines were instrumented with a specially designed canal occlusion transducer, which dynamically monitored canal occlusion during axial compressive impact. Six specimens were subjected to a fast-loading rate (time to peak load, approximately 20 msec), and the other six were subjected to a slow-loading rate (time to peak load, approximately 250 msec). After impact, two different postinjury canal occlusion measurements were performed. RESULTS: Each of the six specimens subjected to the fast-loading rate incurred burst fractures, whereas the slow-loading rate produced six wedge-compression fractures. For the fast-rate group, the postinjury occlusion-measurements were significantly smaller than the transient occlusion. In contrast, transient occlusion was not found to be significantly different from postinjury occlusion in the slow-rate group. All of the comparisons between loading rate groups showed significant differences, with the fast-rate fractures producing larger amounts of canal occlusion in every category. CONCLUSIONS: The findings indicate that even if canal occlusion could be measured immediately after axial compressive trauma, the measurement would underestimate the maximal amount of transient canal occlusion. Therefore, postinjury measurement of canal occlusion may indicate a smaller degree of neurologic deficit than what might be expected if the transient occlusion could be measured.  相似文献   
19.
We report a natural product compound isolated from Syzygium polycephalum known as 3,4,3′-tri-O-methylellagic acid (T-EA) as a candidate drug for cancer treatment. The characterization of the isolated T-EA compound was carried out using various spectroscopic methods. The in vitro evaluation showcased the inhibition activity of T-EA towards the T47D and HeLa cell lines with EC50 values of 55.35 ± 6.28 μg mL−1 and 12.57 ± 2.22 μg mL−1, respectively. Meanwhile, the in silico evaluation aimed to understand the interaction of T-EA with enzymes responsible for cancer regulation at the molecular level by targeting the hindrance of cyclin-dependent kinase 9 (CDK9) and sirtuin 1 (SIRT1) enzymes. T-EA showed a binding free energy towards the SIRT1 protein of ΔGbind (MM-GBSA): −30.98 ± 0.25 kcal mol−1 and ΔGbind (MM-PBSA): −24.07 ± 0.30 kcal mol−1, while that of CDK9 was ΔGbind (MM-GBSA): −29.50 ± 0.22 kcal mol−1 and ΔGbind (MM-PBSA): −25.87 ± 0.40 kcal mol−1. The obtained results from this research could be considered as important information on 3,4,3′-tri-O-methylellagic acid as a drug to treat cervical and breast cancers.

We report a natural product compound isolated from Syzygium polycephalum known as 3,4,3′-tri-O-methylellagic acid (T-EA) as a candidate drug for cancer treatment using in vitro and in silico approaches.  相似文献   
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号