全文获取类型
收费全文 | 359篇 |
免费 | 30篇 |
出版年
2023年 | 3篇 |
2022年 | 4篇 |
2021年 | 5篇 |
2020年 | 6篇 |
2019年 | 6篇 |
2018年 | 8篇 |
2017年 | 7篇 |
2016年 | 11篇 |
2015年 | 20篇 |
2014年 | 26篇 |
2013年 | 21篇 |
2012年 | 37篇 |
2011年 | 41篇 |
2010年 | 26篇 |
2009年 | 23篇 |
2008年 | 31篇 |
2007年 | 15篇 |
2006年 | 15篇 |
2005年 | 15篇 |
2004年 | 10篇 |
2003年 | 8篇 |
2002年 | 13篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 5篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1985年 | 2篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1979年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有389条查询结果,搜索用时 15 毫秒
101.
Dr S. A. Hassan F. Bigler H. Bogenschütz E. Boller J. Brun J. N. M. Calis J. Coremans-Pelseneer C. Duso A. Grove U. Heimbach N. Helyer H. Hokkanen G. B. Lewis F. Mansour L. Moreth L. Polgar L. Samsøe-Petersen B. Sauphanor A. Stäubli G. Sterk A. Vainio M. van de Veire G. Viggiani H. Vogt 《BioControl》1994,39(1):107-119
The side effects of 5 insecticides, 8 fungicides and 6 herbicides on 24 species of beneficial organisms were tested by members of the Working Group «Pesticides and Beneficial Organisms» of the International Organization for Biological Control (IOBC), West Palaearctic Regional Section (WPRS). The tests were conducted by 24 members in 11 countries according to internationally approved guidelines. The insecticide buprofezin (Applaud), the fungicides triforine (Saprol), procymidone (Sumisclex), anilazine (Dyrene), triadimenol (Bayfidan), hexaconazole (Anvil), tridemorph (Calixin) and the herbicides tralkoxydim (Grasp), bentazone (Basagran) were harmless to nearly all the beneficial organisms. Diflubenzuron (Dimilin) affected spiders and the larvae of predatory insects. The remaining 10 preparations were more toxic and should therefore be further tested in semi-field and field experiment on relevant organisms. 相似文献
102.
Fianne L. P. Sips Christian A. Tiemann Maaike H. Oosterveer Albert K. Groen Peter A. J. Hilbers Natal A. W. van Riel 《PLoS computational biology》2014,10(5)
Disturbances of lipoprotein metabolism are recognized as indicators of cardiometabolic disease risk. Lipoprotein size and composition, measured in a lipoprotein profile, are considered to be disease risk markers. However, the measured profile is a collective result of complex metabolic interactions, which complicates the identification of changes in metabolism. In this study we aim to develop a method which quantitatively relates murine lipoprotein size, composition and concentration to the molecular mechanisms underlying lipoprotein metabolism. We introduce a computational framework which incorporates a novel kinetic model of murine lipoprotein metabolism. The model is applied to compute a distribution of plasma lipoproteins, which is then related to experimental lipoprotein profiles through the generation of an in silico lipoprotein profile. The model was first applied to profiles obtained from wild-type C57Bl/6J mice. The results provided insight into the interplay of lipoprotein production, remodelling and catabolism. Moreover, the concentration and metabolism of unmeasured lipoprotein components could be determined. The model was validated through the prediction of lipoprotein profiles of several transgenic mouse models commonly used in cardiovascular research. Finally, the framework was employed for longitudinal analysis of the profiles of C57Bl/6J mice following a pharmaceutical intervention with a liver X receptor (LXR) agonist. The multifaceted regulatory response to the administration of the compound is incompletely understood. The results explain the characteristic changes of the observed lipoprotein profile in terms of the underlying metabolic perturbation and resultant modifications of lipid fluxes in the body. The Murine Lipoprotein Profiler (MuLiP) presented here is thus a valuable tool to assess the metabolic origin of altered murine lipoprotein profiles and can be applied in preclinical research performed in mice for analysis of lipid fluxes and lipoprotein composition. 相似文献
103.
BACKGROUND AND AIMS: It is well established that the nitrogen content of plants, including lettuce, decreases with time. It has also been observed that water content of lettuce increases between planting and harvest. This paper is an attempt at modelling these observations. METHODS: An existing dynamic model (Nicolet), designed to predict growth and nitrate content of glasshouse lettuce, is modified to accommodate the ontogenetic changes of reduced-nitrogen and water contents (on a dry matter basis). The decreasing reduced-N content and the increasing water content are mimicked by dividing the originally uniform plant into 'metabolically active' tissue and 'support' tissue. The 'metabolic' tissue is assumed to contain a higher nitrogen content and a lower water content than the 'support' tissue. As the plants grow, the ratio of 'support' to 'metabolic' tissue increases, resulting in an increased mean water content and a decreased reduced-N content. Simulations with the new model are compared with experimental glasshouse data over four seasons. KEY RESULTS: The empirical linear relationship between water and reduced-N contents, matches, to a good approximation, the corresponding relationship based on the model. The agreement between the two makes it possible to effectively uncouple the estimation of the 'ontogenetic' parameters from the estimation of the other parameters. The growth and nitrate simulation results match the data rather well and are hardly affected by the new refinement. The reduced-N and water contents are predicted much better with the new model. CONCLUSION: Prediction of nitrogen uptake for the substantial nitrate pool of lettuce depends on the water content. Hence, the modified model may assist in making better fertilization decisions and better estimates of nitrogen leaching. 相似文献
104.
105.
106.
107.
Deletion of the three distal S1 motifs of Saccharomyces cerevisiae Rrp5p abolishes pre-rRNA processing at site A(2) without reducing the production of functional 40S subunits 下载免费PDF全文
Yeast Rrp5p, one of the few trans-acting proteins required for the biogenesis of both ribosomal subunits, has a remarkable two-domain structure. Its C-terminal region consists of seven tetratricopeptide motifs, several of which are crucial for cleavages at sites A(0) to A(2) and thus for the formation of 18S rRNA. The N-terminal region, on the other hand, contains 12 S1 RNA-binding motifs, most of which are required for processing at site A(3) and thus for the production of the short form of 5.8S rRNA. Yeast cells expressing a mutant Rrp5p protein that lacks S1 motifs 10 to 12 (mutant rrp5Delta6) have a normal growth rate and wild-type steady-state levels of the mature rRNA species, suggesting that these motifs are irrelevant for ribosome biogenesis. Here we show that, nevertheless, in the rrp5Delta6 mutant, pre-rRNA processing follows an alternative pathway that does not include the cleavage of 32S pre-rRNA at site A(2). Instead, the 32S precursor is processed directly at site A(3), producing exclusively 21S rather than 20S pre-rRNA. This is the first evidence that the 21S precursor, which was observed previously only in cells showing a substantial growth defect or as a minor species in addition to the normal 20S precursor, is an efficient substrate for 18S rRNA synthesis. Maturation of the 21S precursor occurs via the same endonucleolytic cleavage at site D as that used for 20S pre-rRNA maturation. The resulting D-A(3) fragment, however, is degraded by both 5'-->3' and 3'-->5' exonuclease digestions, the latter involving the exosome, in contrast to the exclusively 5'-->3' exonucleolytic digestion of the D-A(2) fragment. We also show that rrp5Delta6 cells are hypersensitive to both hygromycin B and cycloheximide, suggesting that, despite their wild-type growth rate, their preribosomes or ribosomes may be structurally abnormal. 相似文献
108.
109.
Laura A. Steenhuis Maaike H. Nauta Claudi L. H. Bocking Gerdina H. M. Pijnenborg 《PloS one》2015,10(10)
AimsThe aim of this study was to examine whether non-verbal therapies are effective in treating depressive symptoms in psychotic disorders.Results10 RCTs were included, of which three were of high quality according to the CTAM. The direct evidence demonstrated a significant effect on the reduction in depressive symptoms relative to treatment as usual (TAU), in favor of overall non-verbal therapy (ES: -0.66, 95% C.I. = -0.88, -0.44) and music therapy (ES: -0.59, 95% C.I. = -0.85, -0.33). Combining both direct and indirect evidence, yoga therapy (ES: -0.79, 95% C.I. = -1.24, -0.35) had a significant effect on depressive symptoms, and occupational therapy (ES: 1.81, 95% C.I. = 0.81, 2.81) was less effective, relative to TAU. Exercise therapy did not show a significant effect on depressive symptoms in comparison to TAU (ES: -0.02 95% C.I. = -0.67, 0.62). Due to inconsistency of study evidence, the indirect effects should be interpreted cautiously.ConclusionsNon-verbal therapies appear to be effective in reducing depressive symptomatology in psychotic disorders, in particular music therapy and yoga therapy. 相似文献
110.
Maaike Labots Hein A. Van Lith Frauke Ohl Saskia S. Arndt 《Journal of visualized experiments : JoVE》2015,(98)
This protocol describes the modified hole board (mHB), which combines features from a traditional hole board and open field and is designed to measure multiple dimensions of unconditioned behavior in small laboratory mammals (e.g., mice, rats, tree shrews and small primates). This paradigm is a valuable alternative for the use of a behavioral test battery, since a broad behavioral spectrum of an animal’s behavioral profile can be investigated in one single test.The apparatus consists of a box, representing the ‘protected’ area, separated from a group compartment. A board, on which small cylinders are staggered in three lines, is placed in the center of the box, representing the ‘unprotected’ area of the set-up. The cognitive abilities of the animals can be measured by baiting some cylinders on the board and measuring the working and reference memory. Other unconditioned behavior, such as activity-related-, anxiety-related- and social behavior, can be observed using this paradigm. Behavioral flexibility and the ability to habituate to a novel environment can additionally be observed by subjecting the animals to multiple trials in the mHB, revealing insight into the animals’ adaptive capacities.Due to testing order effects in a behavioral test battery, naïve animals should be used for each individual experiment. By testing multiple behavioral dimensions in a single paradigm and thereby circumventing this issue, the number of experimental animals used is reduced. Furthermore, by avoiding social isolation during testing and without the need to food deprive the animals, the mHB represents a behavioral test system, inducing if any, very low amount of stress. 相似文献