全文获取类型
| 收费全文 | 123342篇 |
| 免费 | 7609篇 |
| 国内免费 | 1077篇 |
专业分类
| 耳鼻咽喉 | 1907篇 |
| 儿科学 | 1949篇 |
| 妇产科学 | 1875篇 |
| 基础医学 | 19619篇 |
| 口腔科学 | 3061篇 |
| 临床医学 | 11453篇 |
| 内科学 | 21680篇 |
| 皮肤病学 | 3908篇 |
| 神经病学 | 10036篇 |
| 特种医学 | 7280篇 |
| 外科学 | 16525篇 |
| 综合类 | 509篇 |
| 现状与发展 | 3篇 |
| 一般理论 | 27篇 |
| 预防医学 | 6365篇 |
| 眼科学 | 3092篇 |
| 药学 | 11258篇 |
| 中国医学 | 1442篇 |
| 肿瘤学 | 10039篇 |
出版年
| 2023年 | 663篇 |
| 2022年 | 473篇 |
| 2021年 | 3626篇 |
| 2020年 | 2105篇 |
| 2019年 | 2942篇 |
| 2018年 | 3679篇 |
| 2017年 | 2990篇 |
| 2016年 | 3901篇 |
| 2015年 | 5438篇 |
| 2014年 | 6446篇 |
| 2013年 | 7514篇 |
| 2012年 | 11244篇 |
| 2011年 | 10781篇 |
| 2010年 | 6188篇 |
| 2009年 | 5307篇 |
| 2008年 | 7532篇 |
| 2007年 | 7155篇 |
| 2006年 | 6464篇 |
| 2005年 | 5990篇 |
| 2004年 | 5215篇 |
| 2003年 | 4532篇 |
| 2002年 | 3896篇 |
| 2001年 | 3021篇 |
| 2000年 | 2781篇 |
| 1999年 | 2117篇 |
| 1998年 | 840篇 |
| 1997年 | 634篇 |
| 1996年 | 480篇 |
| 1995年 | 474篇 |
| 1994年 | 412篇 |
| 1993年 | 348篇 |
| 1992年 | 750篇 |
| 1991年 | 702篇 |
| 1990年 | 649篇 |
| 1989年 | 570篇 |
| 1988年 | 480篇 |
| 1987年 | 480篇 |
| 1986年 | 340篇 |
| 1985年 | 384篇 |
| 1984年 | 268篇 |
| 1983年 | 198篇 |
| 1982年 | 152篇 |
| 1981年 | 176篇 |
| 1980年 | 137篇 |
| 1979年 | 221篇 |
| 1978年 | 165篇 |
| 1977年 | 125篇 |
| 1976年 | 146篇 |
| 1975年 | 128篇 |
| 1974年 | 139篇 |
排序方式： 共有10000条查询结果，搜索用时 46 毫秒
51.
52.
53.
So-Young Kim Drew R. Jones Ji-Yeon Kang Chul-Ho Yun 《Xenobiotica; the fate of foreign compounds in biological systems》2019,49(4):397-403
Coumadin (R/S-warfarin) metabolism plays a critical role in patient response to anticoagulant therapy. Several cytochrome P450s oxidize warfarin into R/S-6-, 7-, 8-, 10, and 4′-hydroxywarfarin that can undergo subsequent glucuronidation by UDP-glucuronosyltransferases (UGTs); however, current studies on recombinant UGTs cannot be adequately extrapolated to microsomal glucuronidation capacities for the liver.
Herein, we estimated the capacity of the average human liver to glucuronidate hydroxywarfarin and identified UGTs responsible for those metabolic reactions through inhibitor phenotyping. There was no observable activity toward R/S-warfarin, R/S-10-hydroxywarfarin or R/S-4′-hydroxywarfarin.
The observed metabolic efficiencies (Vmax/Km) toward R/S-6-, 7-, and especially 8-hydroxywarfarin indicated a high glucuronidation capacity to metabolize these compounds.
UGTs demonstrated strong regioselectivity toward the hydroxywarfarins. UGT1A6 and UGT1A1 played a major role in R/S-6- and 7-hydroxywarfarin glucuronidation, respectively, whereas UGT1A9 accounted for almost all of the generation of the R/S-8-hydroxywarfarin glucuronide.
In summary, these studies expanded insights to glucuronidation of hydroxywarfarins by pooled human liver microsomes, novel roles for UGT1A6 and 1A9, and the overall degree of regioselectivity for the UGT reactions.
54.
55.
Early diffusion-weighted imaging and outcome prediction of comatose survivors after suicidal hanging
Dong Won Choi Suk Woo Lee Seong-Hae Jeong Jung Soo Park Hoon Kim 《The American journal of emergency medicine》2019,37(1):5-11
Purpose
Early outcome prediction after suicidal hanging is challenging in comatose survivors. We analysed the early patterns of brain diffusion-weighted magnetic resonance imaging (DWI) abnormalities in comatose survivors after suicidal hanging.Methods
After suicidal hanging, 18 comatose survivors were prospectively evaluated from January 2013 to December 2016. DWI was performed within 3?h after hanging in comatose survivors. We evaluated Utstein style variables and analysed abnormal spatial profile of signal intensity on DWI, brain apparent diffusion coefficient (ADC) values, and qualitative DWI scores to predict neurological outcomes.Results
All hanging associated cardiac arrest (CA) patients demonstrated bad neurological outcomes; 80% of non-CA comatose patients experienced good neurological outcomes. In hanging survivors with CA, cortical grey matter structures and deep grey nuclei exhibited profound ADC reductions and high DWI scores within 3?h after hanging, which was associated with diffuse anoxic brain damage with poor cerebral performance categories scores. CA comatose survivors had significantly lower ADC values and higher DWI scores compared to non-CA comatose survivors in the cortex and deep grey nuclei.Conclusion
Although the presence of CA is the most important clinical prognosticator in hanging-associated comatose survivors, HSI abnormalities and low ADC values in the cortex and deep grey nuclei on DWI performed within 3?h after hanging are well-correlated with unfavourable outcomes regardless of therapeutic hypothermia. Therefore, early DWI may increase the sensitivity of poor outcome prediction and may be an effective combinatorial screening method when available prognostic variables are not reliable or conclusive. 相似文献56.
57.
58.
59.
Nikhil Yegya-Raman Meral Reyhan Sinae Kim Matthew P. Deek Ning Yue Wei Zou Jyoti Malhotra Joseph Aisner Salma K. Jabbour 《Practical radiation oncology》2019,9(1):e74-e82
Purpose
This study aimed to investigate the association between target volume margins and clinical outcomes for patients with inoperable non-small cell lung cancer (NSCLC) treated with concurrent chemoradiation therapy.Methods and materials
We reviewed the records of 82 patients with inoperable NSCLC treated between 2009 and 2016 with concurrent chemoradiation. All patients received positron emission tomography–based treatment planning, 4-dimensional computed tomography simulation to define an internal target volume, and daily cone beam computed tomography. We quantified variations in target volume margins with a margin deviation index (MDI), calculated as the percentage change in equivalent uniform dose between the original planning target volume (PTV) and a standard reference PTV 10 mm beyond the original gross tumor volume, consistent with the minimum margins mandated by recent NSCLC trials. Greater MDIs equated to smaller effective target volume margins. We dichotomized patients by the upper tercile MDI value (5.8%). Endpoints included time to locoregional progression and time to grade ≥ 3 radiation esophagitis (RE3) or radiation pneumonitis (RP3), modelled with the Fine-Gray method.Results
Median follow-up was 37.8 months (range, 5.9-58.1 months). Larger MDIs correlated with smaller clinical target volume (CTV) + PTV margins, larger gross tumor volumes, later treatment year, and intensity modulated radiation therapy use. The risk of locoregional progression did not differ for MDI ≥5.8% versus <5.8% (adjusted hazard ratio: 0.88; P = .76), but the risk of RE3 or RP3 was decreased for MDI ≥5.8% (adjusted hazard ratio: 0.27; P = .027). Patients with MDI ≥5.8% were treated with smaller CTV + PTV margins (median, 5.6 vs 8 mm; P < .0001) and a marginally lower volume of esophagus receiving ≥50 Gy (median, 31.1% vs 35.3%; P = .069).Conclusions
Smaller margins were used for larger tumors but were not associated with an increase in locoregional failures. Additional studies could clarify whether smaller margins, when used alongside modern radiation therapy techniques, decrease treatment-related toxicity for inoperable NSCLC. 相似文献60.
Fabrice Barlesi Edward B. Garon Dong-Wan Kim Enriqueta Felip Ji-Youn Han Joo-Hang Kim Myung-Ju Ahn Mary Jo Fidler Matthew A. Gubens Gilberto de Castro Veerle Surmont Qiao Li Anne C. Deitz Gregory M. Lubiniecki Roy S. Herbst 《Journal of thoracic oncology》2019,14(5):793-801