全文获取类型
收费全文 | 2430733篇 |
免费 | 204914篇 |
国内免费 | 8486篇 |
专业分类
耳鼻咽喉 | 35113篇 |
儿科学 | 73443篇 |
妇产科学 | 63680篇 |
基础医学 | 341159篇 |
口腔科学 | 68750篇 |
临床医学 | 222408篇 |
内科学 | 474495篇 |
皮肤病学 | 49222篇 |
神经病学 | 202814篇 |
特种医学 | 99610篇 |
外国民族医学 | 907篇 |
外科学 | 366762篇 |
综合类 | 68014篇 |
现状与发展 | 29篇 |
一般理论 | 984篇 |
预防医学 | 194085篇 |
眼科学 | 57525篇 |
药学 | 185255篇 |
69篇 | |
中国医学 | 8142篇 |
肿瘤学 | 131667篇 |
出版年
2019年 | 19397篇 |
2018年 | 26538篇 |
2017年 | 21011篇 |
2016年 | 22955篇 |
2015年 | 26869篇 |
2014年 | 37977篇 |
2013年 | 55204篇 |
2012年 | 75133篇 |
2011年 | 79052篇 |
2010年 | 46999篇 |
2009年 | 44722篇 |
2008年 | 73514篇 |
2007年 | 77585篇 |
2006年 | 78283篇 |
2005年 | 75787篇 |
2004年 | 72148篇 |
2003年 | 69784篇 |
2002年 | 68456篇 |
2001年 | 113793篇 |
2000年 | 117472篇 |
1999年 | 98793篇 |
1998年 | 26878篇 |
1997年 | 24436篇 |
1996年 | 24282篇 |
1995年 | 24971篇 |
1994年 | 23528篇 |
1993年 | 21753篇 |
1992年 | 79587篇 |
1991年 | 76681篇 |
1990年 | 73767篇 |
1989年 | 71009篇 |
1988年 | 65912篇 |
1987年 | 64907篇 |
1986年 | 61411篇 |
1985年 | 58444篇 |
1984年 | 44193篇 |
1983年 | 37571篇 |
1982年 | 22821篇 |
1981年 | 20247篇 |
1979年 | 41233篇 |
1978年 | 28916篇 |
1977年 | 24248篇 |
1976年 | 22757篇 |
1975年 | 23909篇 |
1974年 | 29587篇 |
1973年 | 28018篇 |
1972年 | 26210篇 |
1971年 | 24141篇 |
1970年 | 22728篇 |
1969年 | 21064篇 |
排序方式: 共有10000条查询结果,搜索用时 187 毫秒
91.
92.
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
93.
Emilie M.J. van Brummelen Sanne Huijberts Carla van Herpen Ingrid Desar Frans Opdam Robin van Geel Serena Marchetti Neeltje Steeghs Kim Monkhorst Bas Thijssen Hilde Rosing Alwin Huitema Jos Beijnen Rene Bernards Jan Schellens 《The oncologist》2021,26(4):290-e545
Lessons Learned
- Afatinib and selumetinib can be combined in continuous and intermittent dosing schedules, albeit at lower doses than approved for monotherapy.
- Maximum tolerated dose for continuous and intermittent schedules is afatinib 20 mg once daily and selumetinib 25 mg b.i.d.
- Because the anticancer activity was limited, further development of this combination is not recommended until better biomarkers for response and resistance are defined.
94.
95.
96.
97.
Kayla Ann Andrews Joel S. Owen James McCarthy David Wesche Nathalie Gobeau Thaddeus H. Grasela Jrg J. Mhrle 《CTS Clinical and Translational Science》2021,14(2):712
Volunteer infection studies using the induced blood stage malaria (IBSM) model have been shown to facilitate antimalarial drug development. Such studies have traditionally been undertaken in single‐dose cohorts, as many as necessary to obtain the dose‐response relationship. To enhance ethical and logistic aspects of such studies, and to reduce the number of cohorts needed to establish the dose‐response relationship, we undertook a retrospective in silico analysis of previously accrued data to improve study design. A pharmacokinetic (PK)/pharmacodynamic (PD) model was developed from initial fictive‐cohort data for OZ439 (mixing the data of the three single‐dose cohorts as: n = 2 on 100 mg, 2 on 200 mg, and 4 on 500 mg). A three‐compartment model described OZ439 PKs. Net growth of parasites was modeled using a Gompertz function and drug‐induced parasite death using a Hill function. Parameter estimates for the PK and PD models were comparable for the multidose single‐cohort vs. the pooled analysis of all cohorts. Simulations based on the multidose single‐cohort design described the complete data from the original IBSM study. The novel design allows for the ascertainment of the PK/PD relationship early in the study, providing a basis for rational dose selection for subsequent cohorts and studies. Study Highlights
- WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?
- WHAT QUESTION DID THIS STUDY ADDRESS?
- WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?
- HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?
98.
Seung Ki Min Se Kyung Lee Jinsun Woo Sung Mi Jung Jai Min Ryu Jonghan Yu Jeong Eon Lee Seok Won Kim Byung Joo Chae Seok Jin Nam 《JOURNAL OF BREAST CANCER》2021,24(1):75
PurposeTumor size and lymph node metastasis are important factors that contribute to the progression of breast cancer. We aimed to analyze the relationship between tumor size and lymph node metastasis molecular subtype and examine the effects of nodal metastasis on overall survival (OS).MethodsWe retrospectively reviewed the data of 16,552 patients who underwent breast surgery in Samsung Medical Center between 2000 and 2015. Information on tumor size (largest diameter of the invasive component), number of positive lymph nodes, and molecular subtype were obtained. We constructed a linear regression model to evaluate the relationship between tumor size and lymph node metastasis. To determine the effect of nodal metastasis on OS, we performed a Cox proportional regression analysis with Np/T (number of metastatic lymph nodes [n]/tumor size [cm]).ResultsThis study included 12,007 patients with a median follow-up of 62 months. The linear regression coefficients were 1.043 for luminal A, 1.024 for luminal B, 0.656 for HER2, and 0.435 for triple-negative breast cancer (TNBC) subtypes. No significant difference was observed in the coefficients between the luminal A and B subtypes (p = 0.797), while all other coefficients showed significant difference. After adjusting for other risk factors, the hazard ratio (HR) of Np/T for each subtype was significant for OS: luminal A (HR, 1.134; 95% confidence interval [CI], 1.097–1.171; p < 0.001), luminal B (HR, 1.049; 95% CI, 1.013–1.086; p = 0.007), HER2 (HR, 1.069; 95% CI, 1.014–1.126; p = 0.013), and TNBC (HR, 1.038; 95% CI, 1.01–1.067; p = 0.008).ConclusionThe incidence of lymph node metastasis differed according to molecular subtype. Luminal types have higher incidence of nodal metastasis than HER2 and TNBC. The HR of Np/T was highest in luminal A subtypes and lowest in TNBC subtypes. 相似文献
99.
Girish B Nair Craig J Galban Sayf Al-Katib Robert Podolsky Maarten van den Berge Craig Stevens Edward Castillo 《The British journal of radiology》2021,94(1118)
Objective:To evaluate CT-ventilation imaging (CTVI) within a well-characterized, healthy cohort with no respiratory symptoms and examine the correlation between CTVI and concurrent pulmonary function test (PFT).Methods:CT scans and PFTs from 77 Caucasian participants in the NORM dataset (clinicaltrials.gov ) were analyzed. CTVI was generated using the robust Integrated Jacobian Formulation (IJF) method. IJF estimated total lung capacity (TLC) was computed from CTVI. Bias-adjusted Pearson’s correlation between PFT and IJF-based TLC was computed.Results:IJF- and PFT-measured TLC showed a good correlation for both males and females [males: 0.657, 95% CI (0.438–0.797); females: 0.667, 95% CI (0.416–0.817)]. When adjusting for age, height, smoking, and abnormal CT scan, correlation moderated [males: 0.432, 95% CI (0.129–0.655); females: 0.540, 95% CI (0.207–0.753)]. Visual inspection of CTVI revealed participants who had functional defects, despite the fact that all participant had normal high-resolution CT scan.Conclusion:In this study, we demonstrate that IJF computed CTVI has good correlation with concurrent PFT in a well-validated patient cohort with no respiratory symptoms.Advances in knowledge:IJF-computed CTVI’s overall numerical robustness and consistency with PFT support its potential as a method for providing spatiotemporal assessment of high and low function areas on volumetric non-contrast CT scan. NCT00848406相似文献
100.
G.R. Iball D. Tolan G.R. Avery L.H. Cope T. Hoare H. Lambie A. Lowe R.J. de Noronha C.L. Roberts M.E. Wilkinson P. Woolfall 《Clinical radiology》2021,76(8):626.e13-626.e21