全文获取类型
收费全文 | 486篇 |
免费 | 50篇 |
出版年
2023年 | 2篇 |
2022年 | 6篇 |
2021年 | 11篇 |
2020年 | 7篇 |
2019年 | 6篇 |
2018年 | 16篇 |
2017年 | 8篇 |
2016年 | 9篇 |
2015年 | 36篇 |
2014年 | 31篇 |
2013年 | 26篇 |
2012年 | 54篇 |
2011年 | 40篇 |
2010年 | 30篇 |
2009年 | 22篇 |
2008年 | 30篇 |
2007年 | 34篇 |
2006年 | 21篇 |
2005年 | 30篇 |
2004年 | 22篇 |
2003年 | 18篇 |
2002年 | 19篇 |
2001年 | 4篇 |
2000年 | 2篇 |
1999年 | 4篇 |
1998年 | 4篇 |
1997年 | 6篇 |
1996年 | 4篇 |
1995年 | 8篇 |
1993年 | 6篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1989年 | 1篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1985年 | 3篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1977年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有536条查询结果,搜索用时 15 毫秒
61.
Oelze VM Koch JK Kupke K Nehlich O Zäuner S Wahl J Weise SM Rieckhoff S Richards MP 《American journal of physical anthropology》2012,148(3):406-421
For the Early Iron Age western Hallstatt culture, which includes the site of Magdalenenberg in southwest Germany, it has been proposed that people were mobile and maintained far reaching social and trading networks throughout Europe. We tested this hypothesis by analyzing multiple isotopes (strontium, oxygen, sulfur, carbon, and nitrogen) of the preserved skeletons from the Magdalenenberg elite cemetery to determine diets and to look for evidence of mobility. The analysis of carbon, nitrogen, and sulfur isotope ratios in collagen of humans (n = 50) and associated domestic fauna (n = 10) indicates a terrestrial-based diet. There was a heterogeneous range of isotope values in both strontium (0.70725 to 0.71923, n = 76) and oxygen (13.4‰ to 18.5‰, n = 78) measured in tooth enamel. Although many of the individuals had values consistent with being from Hallstatt culture sites within southwest Germany, some individuals likely originated from further afield. Possible areas include the Alps of Switzerland and Austria or even locations in Italy. Our study strongly supports the assumption of far reaching social and economic networks in the western Hallstatt culture. 相似文献
62.
van Ierssel SH Hoymans VY Van Craenenbroeck EM Van Tendeloo VF Vrints CJ Jorens PG Conraads VM 《PloS one》2012,7(2):e31496
Background
Circulating endothelial microparticles (EMP) reflect the condition of the endothelium and are of increasing interest in cardiovascular and inflammatory diseases. Recently, increased numbers of EMP following oral fat intake, possibly due to acute endothelial injury, have been reported. On the other hand, the direct interference of lipids with the detection of EMP has been suggested. This study aimed to investigate the effect of lipid-rich solutions, commonly administered in clinical practice, on the detection, both in vitro and in vivo, of EMP.Methods
For the in vitro assessment, several lipid-rich solutions were added to whole blood of healthy subjects (n = 8) and patients with coronary heart disease (n = 5). EMP (CD31+/CD42b−) were detected in platelet poor plasma by flow cytometry. For the in vivo study, healthy volunteers were evaluated on 3 different study-days: baseline evaluation, following lipid infusion and after a NaCl infusion. EMP quantification, lipid measurements and peripheral arterial tonometry were performed on each day.Results
Both in vitro addition and in vivo administration of lipids significantly decreased EMP (from 198.6 to 53.0 and from 272.6 to 90.6/µl PPP, respectively, p = 0.001 and p = 0.012). The EMP number correlated inversely with the concentration of triglycerides, both in vitro and in vivo (r = −0.707 and −0.589, p<0.001 and p = 0.021, respectively). The validity of EMP as a marker of endothelial function is supported by their inverse relationship with the reactive hyperemia index (r = −0.758, p = 0.011). This inverse relation was confounded by the intravenous administration of lipids.Conclusion
The confounding effect of high circulating levels of lipids, commonly found in patients that receive intravenous lipid-based solutions, should be taken into account when flow cytometry is used to quantify EMP. 相似文献63.
Theresa H Page Peter J Charles Anna M Piccinini Vicky Nicolaidou Peter C Taylor Kim S Midwood 《Arthritis research & therapy》2012,14(6):R260
Introduction
The aim of this study was to examine whether circulating levels of the pro-inflammatory glycoprotein tenascin-C (TNC) are elevated in musculoskeletal disorders including rheumatoid arthritis (RA) and to assess in RA whether levels are related to clinical disease status and/or patient response to treatment.Methods
TNC in serum or plasma was quantified by ELISA. Samples from 4 cohorts of RA patients were examined and compared to normal human subjects and to patients with other inflammatory diseases.Results
Circulating TNC levels were significantly raised in patients with RA, as well as patients with systemic lupus erythematosus, idiopathic inflammatory myositis, psoriatic arthritis and ankylosing spondylitis, whilst patients with Sjogren''s syndrome displayed levels similar to healthy controls. The highest levels of TNC were observed in RA patients with late stage disease. In early disease TNC levels correlated positively with ultrasound determined erosion scores. Treatment of early RA patients with infliximab plus methotrexate (MTX) resulted in a transient decrease in circulating TNC over the first year of therapy. In contrast, TNC levels increased over time in RA patients receiving MTX alone. In patients treated with infliximab plus MTX, baseline TNC levels significantly correlated with tender joint counts (TJC) at 18 and 54 weeks after initiation of infliximab therapy.Conclusions
Raised circulating TNC levels are detected in specific inflammatory diseases. Levels are especially high in RA where they may act as a biomarker of bone erosion and a predictor of the effect of infliximab on RA patient joint pain. 相似文献64.
65.
Oliver Windram Priyadharshini Madhou Stuart McHattie Claire Hill Richard Hickman Emma Cooke Dafyd J. Jenkins Christopher A. Penfold Laura Baxter Emily Breeze Steven J. Kiddle Johanna Rhodes Susanna Atwell Daniel J. Kliebenstein Youn-sung Kim Oliver Stegle Karsten Borgwardt Cunjin Zhang Alex Tabrett Roxane Legaie Jonathan Moore B?rbel Finkenstadt David L. Wild Andrew Mead David Rand Jim Beynon Sascha Ott Vicky Buchanan-Wollaston Katherine J. Denby 《The Plant cell》2012,24(9):3530-3557
66.
67.
G.O.D.'s Holy Grail: discovery of the RAG proteins 总被引:1,自引:0,他引:1
68.
Gunderson EP Sternfeld B Wellons MF Whitmer RA Chiang V Quesenberry CP Lewis CE Sidney S 《Obesity (Silver Spring, Md.)》2008,16(5):1078-1084
Objective: To examine whether childbearing is associated with increased visceral adiposity and whether the increase is proportionally larger than other depots. Methods and Procedures: This prospective study examined changes in adiposity assessed via computed tomography (CT) and dual‐energy X‐ray absorptiometry among 122 premenopausal women (50 black, 72 white) examined in 1995–1996 and again in 2000–2001. During the 5‐year interval, 14 women had one interim birth and 108 had no interim births. Multiple linear regression models estimated mean (95% confidence interval (CI)) 5‐year changes in anthropometric and adiposity measures by interim births adjusted for age, race, and changes in total and subcutaneous adiposity. Results: We found no significant differences between one interim birth and no interim births for 5‐year changes in weight, BMI, total body fat, subcutaneous adipose tissue, or total abdominal adipose tissue. Visceral adipose tissue increased by 40 and 14% above initial levels for 1 birth and 0 birth groups, respectively. Having 1 birth vs. 0 births was associated with a greater increase in visceral adipose tissue of 18.0 cm2 (4.8, 31.2), P < 0.01; gain of 27.1 cm2 (14.5, 39.7) vs. 9.2 cm2 (4.8, 13.6), and a borderline greater increase in waist girth of 2.3 cm (0, 4.5), P = 0.05; gain of 6.3 cm (4.1, 8.5) vs. 4.0 cm (3.2, 4.8), controlling for gain in total body fat and covariates. Discussion: Pregnancy may be associated with preferential accumulation of adipose tissue in the visceral compartment for similar gains in total body fat. Further investigation is needed to confirm these findings and determine whether excess visceral fat deposition with pregnancy adversely affects metabolic risk profiles among women. 相似文献
69.
70.