全文获取类型
收费全文 | 1590篇 |
免费 | 115篇 |
国内免费 | 2篇 |
出版年
2023年 | 6篇 |
2022年 | 6篇 |
2021年 | 25篇 |
2020年 | 11篇 |
2019年 | 27篇 |
2018年 | 28篇 |
2017年 | 41篇 |
2016年 | 60篇 |
2015年 | 80篇 |
2014年 | 108篇 |
2013年 | 104篇 |
2012年 | 128篇 |
2011年 | 122篇 |
2010年 | 83篇 |
2009年 | 71篇 |
2008年 | 99篇 |
2007年 | 91篇 |
2006年 | 96篇 |
2005年 | 65篇 |
2004年 | 72篇 |
2003年 | 66篇 |
2002年 | 58篇 |
2001年 | 23篇 |
2000年 | 21篇 |
1999年 | 21篇 |
1998年 | 13篇 |
1997年 | 18篇 |
1996年 | 8篇 |
1995年 | 12篇 |
1994年 | 12篇 |
1993年 | 15篇 |
1992年 | 18篇 |
1991年 | 10篇 |
1990年 | 5篇 |
1989年 | 8篇 |
1988年 | 7篇 |
1987年 | 6篇 |
1986年 | 6篇 |
1985年 | 8篇 |
1984年 | 7篇 |
1982年 | 3篇 |
1981年 | 3篇 |
1980年 | 5篇 |
1979年 | 9篇 |
1976年 | 3篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1969年 | 2篇 |
1967年 | 2篇 |
1956年 | 2篇 |
排序方式: 共有1707条查询结果,搜索用时 203 毫秒
1.
2.
Stein J. Janssen Annelien L. Bredenoord Wouter Dhert Marinus de Kleuver F. Cumhur Oner Jorrit-Jan Verlaan 《PloS one》2015,10(6)
Conflicts of interest arising from ties between pharmaceutical industry and physicians are common and may bias research. The extent to which these ties exist among editorial board members of medical journals is not known. This study aims to determine the prevalence and financial magnitude of potential conflicts of interest among editorial board members of five leading spine journals. The editorial boards of: The Spine Journal; Spine; European Spine Journal; Journal of Neurosurgery: Spine; and Journal of Spinal Disorders & Techniques were extracted on January 2013 from the journals’ websites. Disclosure statements were retrieved from the 2013 disclosure index of the North American Spine Society; the program of the 20th International Meeting on Advanced Spine Techniques; the program of the 48th Annual Meeting of the Scoliosis Research Society; the program of the AOSpine global spine congress; the presentations of the 2013 Annual Eurospine meeting; and the disclosure index of the American Academy of Orthopaedic Surgeons. Names of the editorial board members were compared with the individuals who completed a disclosure for one of these indexes. Disclosures were extracted when full names matched. Two hundred and ten (29%) of the 716 identified editorial board members reported a potential conflict of interest and 154 (22%) reported nothing to disclose. The remaining 352 (49%) editorial board members had no disclosure statement listed for one of the indexes. Eighty-nine (42%) of the 210 editorial board members with a potential conflict of interest reported a financial relationship of more than $10,000 during the prior year. This finding confirms that potential conflicts of interest exist in editorial boards which might influence the peer review process and can result in bias. Academia and medical journals in particular should be aware of this and strive to improve transparency of the review process. We emphasize recommendations that contribute to achieving this goal. 相似文献
3.
J Maes 《Plastic and reconstructive surgery》1974,54(3):346-347
4.
Abstract. Cell aggregation in Dictyostelium discoideum is a chemotactic process mediated by cyclic adenosine monophosphate (CAMP), which is detected by cell surface receptors. The cAMP signal is degraded by cAMP phosphodiesterase. The possibility that cAMP signals are also used for cell communication in the multicellular stages was studied by determining whether the cAMP receptors, which are essential for signal transduction, continue to function in these stages. During slug migration, the number of binding sites per cell decreases to about 15% of the maximum level acquired during aggregation. At the onset of fruiting body formation, a three- to Four-Fold increase in cAMP binding activity occurs. This increase coincides with an increase in cAMP phosphodiesterase. Both phenomena suggest that cell-cell communication mediated by cAMP is used during culmination. During both slug migration and early culmination, the prestalk cells exhibit about twice as much binding activity as the prespore cells. 相似文献
5.
H. Blondeel M. P. Perring E. De Lombaerde L. Depauw D. Landuyt S. Govaert S. L. Maes P. Vangansbeke P. De Frenne K. Verheyen 《Plant biology (Stuttgart, Germany)》2020,22(4):601-614
- Intraspecific trait variation (ITV; i.e. variability in mean and/or distribution of plant attribute values within species) can occur in response to multiple drivers. Environmental change and land‐use legacies could directly alter trait values within species but could also affect them indirectly through changes in vegetation cover. Increasing variability in environmental conditions could lead to more ITV, but responses might differ among species. Disentangling these drivers on ITV is necessary to accurately predict plant community responses to global change.
- We planted herb communities into forest soils with and without a recent history of agriculture. Soils were collected across temperate European regions, while the 15 selected herb species had different colonizing abilities and affinities to forest habitat. These mesocosms (384) were exposed to two‐level full‐factorial treatments of warming, nitrogen addition and illumination. We measured plant height and specific leaf area (SLA).
- For the majority of species, mean plant height increased as vegetation cover increased in response to light addition, warming and agricultural legacy. The coefficient of variation (CV) for height was larger in fast‐colonizing species. Mean SLA for vernal species increased with warming, while light addition generally decreased mean SLA for shade‐tolerant species. Interactions between treatments were not important predictors.
- Environmental change treatments influenced ITV, either via increasing vegetation cover or by affecting trait values directly. Species’ ITV was individualistic, i.e. species responded to different single resource and condition manipulations that benefited their growth in the short term. These individual responses could be important for altered community organization after a prolonged period.
6.
Guy Froyen An Broekmans Femke Hillen Karin Pat Ruth Achten Jeroen Mebis Jean-Luc Rummens Johan Willemse Brigitte Maes 《PloS one》2016,11(4)
The inevitable switch from standard molecular methods to next-generation sequencing for the molecular profiling of tumors is challenging for most diagnostic laboratories. However, fixed validation criteria for diagnostic accreditation are not in place because of the great variability in methods and aims. Here, we describe the validation of a custom panel of hotspots in 24 genes for the detection of somatic mutations in non-small cell lung carcinoma, colorectal carcinoma and malignant melanoma starting from FFPE sections, using 14, 36 and 5 cases, respectively. The targeted hotspots were selected for their present or future clinical relevance in solid tumor types. The target regions were enriched with the TruSeq approach starting from limited amounts of DNA. Cost effective sequencing of 12 pooled libraries was done using a micro flow cell on the MiSeq and subsequent data analysis with MiSeqReporter and VariantStudio. The entire workflow was diagnostically validated showing a robust performance with maximal sensitivity and specificity using as thresholds a variant allele frequency >5% and a minimal amplicon coverage of 300. We implemented this method through the analysis of 150 routine diagnostic samples and identified clinically relevant mutations in 16 genes including KRAS (32%), TP53 (32%), BRAF (12%), APC (11%), EGFR (8%) and NRAS (5%). Importantly, the highest success rate was obtained when using also the low quality DNA samples. In conclusion, we provide a workflow for the validation of targeted NGS by a custom-designed pan-solid tumor panel in a molecular diagnostic lab and demonstrate its robustness in a clinical setting. 相似文献
7.
8.
9.
Dorina Ibi Manon Boot Martijn E.T. Dollé J. Wouter Jukema Frits R. Rosendaal Constantinos Christodoulides Matt J. Neville Robert Koivula Patrick C.N. Rensen Fredrik Karpe Raymond Noordam Ko Willems van Dijk 《Journal of lipid research》2022,63(5):100193
Triglyceride (TG)-lowering LPL variants in combination with genetic LDL-C-lowering variants are associated with reduced risk of coronary artery disease (CAD). Genetic variation in the APOA5 gene encoding apolipoprotein A-V also strongly affects TG levels, but the potential clinical impact and underlying mechanisms are yet to be resolved. Here, we aimed to study the effects of APOA5 genetic variation on CAD risk and plasma lipoproteins through factorial genetic association analyses. Using data from 309,780 European-ancestry participants from the UK Biobank, we evaluated the effects of lower TG levels as a result of genetic variation in APOA5 and/or LPL on CAD risk with or without a background of reduced LDL-C. Next, we compared lower TG levels via APOA5 and LPL variation with over 100 lipoprotein measurements in a combined sample from the Netherlands Epidemiology of Obesity study (N = 4,838) and the Oxford Biobank (N = 6,999). We found that lower TG levels due to combined APOA5 and LPL variation and genetically-influenced lower LDL-C levels afforded the largest reduction in CAD risk (odds ratio: 0.78 (0.73–0.82)). Compared to patients with genetically-influenced lower TG via LPL, genetically-influenced lower TG via APOA5 had similar and independent, but notably larger, effects on the lipoprotein profile. Our results suggest that lower TG levels as a result of APOA5 variation have strong beneficial effects on CAD risk and the lipoprotein profile, which suggest apo A-V may be a potential novel therapeutic target for CAD prevention. 相似文献
10.
G Beunen J Lefevre A L Claessens R Lysens H Maes R Renson J Simons B Vanden Eynde B Vanreusel C Van den Bossche 《European journal of applied physiology and occupational physiology》1992,64(6):538-545
This study investigated the age-specific tracking of adult health- and performance-related fitness scores. In addition, the independent contribution of adolescent physical characteristics to the explanation of adult fitness scores was also studied. The sample consisted of 173 adults observed at age 30 years. These subjects had been followed at annual intervals from age 13 to age 18 years and were remeasured at age 30 years. At each age nine fitness tests were administered together with the recording of anthropometric dimensions, biological maturation, sports participation and family characteristics. Tracking was measured by the inter-age correlations at each age between 13 and 18 years and the performance scores at 30 years. The independent contribution of characteristics observed during adolescence to the explanation of adult fitness was investigated through stepwise multiple regression analysis and discriminant analysis with the adult fitness scores as the dependent variables and the fitness, maturation, anthropometric characteristics, sports participation and family background as the independent variables. Tracking between age 13 and age 30 years was moderately high (46% of variance explained) for flexibility, low to moderate (between 19% and 27% of variance explained) for the other fitness parameters and low for pulse recovery and static strength (7% to 11% of variance explained). Between age 18 and age 30 years the tracking was high for flexibility, moderately high for explosive and static strength, and moderate for the other fitness parameters except for pulse recovery. The amount of variance of adult fitness levels explained increased significantly when other characteristics observed during adolescence entered the regressions or discriminant functions.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献