全文获取类型
收费全文 | 2330112篇 |
免费 | 174898篇 |
国内免费 | 3276篇 |
专业分类
耳鼻咽喉 | 32014篇 |
儿科学 | 75665篇 |
妇产科学 | 62665篇 |
基础医学 | 345273篇 |
口腔科学 | 63543篇 |
临床医学 | 209687篇 |
内科学 | 452319篇 |
皮肤病学 | 51701篇 |
神经病学 | 183732篇 |
特种医学 | 87896篇 |
外国民族医学 | 489篇 |
外科学 | 352739篇 |
综合类 | 47297篇 |
现状与发展 | 12篇 |
一般理论 | 848篇 |
预防医学 | 181112篇 |
眼科学 | 54123篇 |
药学 | 174512篇 |
9篇 | |
中国医学 | 4409篇 |
肿瘤学 | 128241篇 |
出版年
2019年 | 19540篇 |
2018年 | 27052篇 |
2017年 | 20357篇 |
2016年 | 22748篇 |
2015年 | 25641篇 |
2014年 | 36101篇 |
2013年 | 53961篇 |
2012年 | 74688篇 |
2011年 | 79416篇 |
2010年 | 47059篇 |
2009年 | 44568篇 |
2008年 | 74616篇 |
2007年 | 79482篇 |
2006年 | 80301篇 |
2005年 | 77791篇 |
2004年 | 74378篇 |
2003年 | 71518篇 |
2002年 | 69198篇 |
2001年 | 108539篇 |
2000年 | 111137篇 |
1999年 | 92854篇 |
1998年 | 25353篇 |
1997年 | 21968篇 |
1996年 | 22354篇 |
1995年 | 22562篇 |
1994年 | 20764篇 |
1993年 | 19593篇 |
1992年 | 71873篇 |
1991年 | 70049篇 |
1990年 | 68353篇 |
1989年 | 65627篇 |
1988年 | 60247篇 |
1987年 | 59078篇 |
1986年 | 55187篇 |
1985年 | 52966篇 |
1984年 | 39235篇 |
1983年 | 33301篇 |
1982年 | 19759篇 |
1981年 | 17768篇 |
1979年 | 35784篇 |
1978年 | 25577篇 |
1977年 | 21129篇 |
1976年 | 20259篇 |
1975年 | 21753篇 |
1974年 | 26089篇 |
1973年 | 24761篇 |
1972年 | 23180篇 |
1971年 | 22013篇 |
1970年 | 20220篇 |
1969年 | 19285篇 |
排序方式: 共有10000条查询结果,搜索用时 140 毫秒
71.
Abd-Allah H. El Ashmawy Kathleen Dowson Ahmed El-Bakoury Hazem A.H. Hosny Rathan Yarlagadda Jonathan Keenan 《The Journal of arthroplasty》2021,36(3):816-822.e1
BackgroundTotal hip and knee arthroplasties are increasingly performed operations, and routine follow-up places huge demands on orthopedic services. This study investigates the effectiveness, patients’ satisfaction, and cost reduction of Virtual Joint Replacement Clinic (VJRC) follow-up of total hip arthroplasty and total knee arthroplasty patients in a university hospital. VJRC is especially valuable when in-person appointments are not advised or feasible such as during the COVID-19 pandemic.MethodsA total of 1749 patients who were invited for VJRC follow-up for knee or hip arthroplasty from January 2017 to December 2018 were included in this retrospective study. Patients were referred to VJRC after their 6-week postoperative review. Routine VJRC postoperative review was undertaken at 1 and 7 years and then 3-yearly thereafter. We evaluated the VJRC patient response rate, acceptability, and outcome. Patient satisfaction was measured in a subgroup of patients using a satisfaction survey. VJRC costs were calculated compared to face-to-face follow-up.ResultsThe VJRC had a 92.05% overall response rate. Only 7.22% required further in-person appointments with only 3% being reviewed by an orthopedic consultant. VJRC resulted in an estimated saving of £42,644 per year at our institution. The patients’ satisfaction survey showed that 89.29% of the patients were either satisfied or very satisfied with VJRC follow-up.ConclusionVJRC follow-up for hip and knee arthroplasty patients is an effective alternative to in-person clinic assessment which is accepted by patients, has high patient satisfaction, and can reduce the cost to both health services and patients. 相似文献
72.
73.
74.
75.
Pauline A. J. Mendelaar Jaco Kraan Mai Van Leonie L. Zeune Leon W. M. M. Terstappen Esther Oomende Hoop John W. M. Martens Stefan Sleijfer 《Molecular oncology》2021,15(1):116
Circulating tumor cells (CTCs) in the blood of cancer patients are of high clinical relevance. Since detection and isolation of CTCs often rely on cell dimensions, knowledge of their size is key. We analyzed the median CTC size in a large cohort of breast (BC), prostate (PC), colorectal (CRC), and bladder (BLC) cancer patients. Images of patient‐derived CTCs acquired on cartridges of the FDA‐cleared CellSearch® method were retrospectively collected and automatically re‐analyzed using the accept software package. The median CTC diameter (μm) was computed per tumor type. The size differences between the different tumor types and references (tumor cell lines and leukocytes) were nonparametrically tested. A total of 1962 CellSearch® cartridges containing 71 612 CTCs were included. In BC, the median computed diameter (CD) of patient‐derived CTCs was 12.4 μm vs 18.4 μm for cultured cell line cells. For PC, CDs were 10.3 μm for CTCs vs 20.7 μm for cultured cell line cells. CDs for CTCs of CRC and BLC were 7.5 μm and 8.6 μm, respectively. Finally, leukocytes were 9.4 μm. CTC size differed statistically significantly between the four tumor types and between CTCs and the reference data. CTC size differences between tumor types are striking and CTCs are smaller than cell line tumor cells, whose size is often used as reference when developing CTC analysis methods. Based on our data, we suggest that the size of CTCs matters and should be kept in mind when designing and optimizing size‐based isolation methods.
Abbreviations
- ACCEPT
- Automated CTC Classification, Enumeration, and PhenoTyping software
- BC
- breast cancer
- BLC
- bladder cancer
- CD
- computed diameter
- CEL
- cultured tumor cell (cell line)
- CK
- cytokeratin
- CRC
- colorectal cancer
- CTC‐L
- circulating tumor cells derived from cerebrospinal fluid (liquor)
- CTCs
- circulating tumor cells
- DAPI
- 4′6‐diamidino‐2‐phenylindole
- EMT
- epithelial–mesenchymal transition
- EpCAM
- epithelial cell adhesion molecule
- IQR
- interquartile range
- KW test
- Kruskal–Wallis test
- MWU test
- Mann–Whitney U test
- NCR
- nucleus/cytoplasm ratio
- P2A
- perimeter to area
- PC
- prostate cancer
- TIF
- tagged Image Format files
- TXT
- text file
- μm
- micrometer
- µm2
- square micrometers
76.
77.
Ivan A. Pelevin Anton Yu. Nalivaiko Dmitriy Yu. Ozherelkov Alexander S. Shinkaryov Stanislav V. Chernyshikhin Alexey N. Arnautov Sergey V. Zmanovsky Alexander A. Gromov 《Materials》2021,14(10)
Aluminum matrix composites (AMC) are of great interest and importance as high-performance materials with enhanced mechanical properties. Al2O3 is a commonly used reinforcement in AMCs fabricated by means of various technological methods, including casting and sintering. Selective laser melting (SLM) is a suitable modern method of the fabrication of net-shape fully dense parts from AMC with alumina. The main results, achievements, and difficulties of SLM applied to AMCs with alumina are discussed in this review and compared with conventional methods. It was shown that the initial powder preparation, namely the particle size distribution, sphericity, and thorough mixing, affected the final microstructure and properties of SLMed materials drastically. The distribution of reinforcing particles tends to consolidate the near-melting pool-edges process because of pushing by the liquid–solid interface during the solidification process that is a common problem of various fabrication methods. The achievement of an homogeneous distribution was shown to be possible through both the thorough mixing of the initial powders and the precise optimization of SLM parameters. The strength of the AMCs fabricated by the SLM method was relatively low compared with materials produced by conventional methods, while for superior relative densities of more than 99%, hardness and tribological properties were obtained, making SLM a promising method for the Al-based matrix composites with Al2O3. 相似文献
78.
79.
80.