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排序方式: 共有259条查询结果,搜索用时 31 毫秒
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Dirk Rohweder Hana Valenta Sarah Sondermann Margit Schollenberger Winfried Drochner Guenter Pahlow Susanne Döll Sven Dänicke 《Mycotoxin Research》2011,27(2):145-153
Mycotoxins are known to affect the health and performance of farm animals. In contrast to cereal grains, the straw is only
rarely analysed for mycotoxins, although contaminated straw could additionally expose farm animals to mycotoxins. For this
reason, two experiments were carried out to examine the effect of pre-harvest Fusarium infection (inoculation with F. culmorum) and different storage conditions on the mycotoxin concentrations in straw. In the first experiment, both the inoculated
and the identically cultivated control straw were stored in rectangular bales either in a barn or outdoors for a time period
of 32 weeks (farm-scale experiment). The second experiment was aimed to examine the mycotoxin concentrations during storage
under controlled conditions in a temperature-controlled climatic chamber, with target dry matter contents of 86%, 82% and
78% using 1.5-l preservation jars (laboratory-scale experiment). While the concentration of deoxynivalenol and its derivates
decreased in the farm-scale experiment when inoculated straw was stored outdoors, the zearalenone concentration increased
within the same time period. The latter effect was also detected for the control straw. These opposite effects were probably
caused by the massive water uptake during the outdoor storage. The only effect we observed in the laboratory-scale experiment
with dry matter contents between 78% and 86% was a more pronounced decrease of the 3-acetyl-deoxynivalenol concentrations
in the inoculated straw with increasing moisture contents. 相似文献
75.
Mijo Simunovic Carsten Mim Thomas C. Marlovits Guenter Resch Vinzenz M. Unger Gregory A. Voth 《Biophysical journal》2013
Key cellular processes are frequently accompanied by protein-facilitated shape changes in the plasma membrane. N-BAR-domain protein modules generate curvature by means of complex interactions with the membrane surface. The way they assemble and the mechanism by which they operate are largely dependent on their binding density. Although the mechanism at lower densities has recently begun to emerge, how membrane scaffolds form at high densities remains unclear. By combining electron microscopy and multiscale simulations, we show that N-BAR proteins at high densities can transform a lipid vesicle into a 3D tubular network. We show that this process is a consequence of excess adhesive energy combined with the local stiffening of the membrane, which occurs in a narrow range of mechanical properties of both the membrane and the protein. We show that lipid diffusion is significantly reduced by protein binding at this density regime and even more in areas of high Gaussian curvature, indicating a potential effect on molecular transport in cells. Finally, we reveal that the breaking of the bilayer topology is accompanied by the nematic arrangement of the protein on the surface, a structural motif that likely drives the formation of reticular structures in living cells. 相似文献
76.
Vanessa Stadlbauer Bettina Leber Sandra Lemesch Slave Trajanoski Mina Bashir Angela Horvath Monika Tawdrous Tatjana Stojakovic Günter Fauler Peter Fickert Christoph H?genauer Ingeborg Klymiuk Philipp Stiegler Manfred Lamprecht Thomas R. Pieber Norbert J. Tripolt Harald Sourij 《PloS one》2015,10(10)
Metabolic syndrome is associated with disturbances in gut microbiota composition. We aimed to investigate the effect of Lactobacillus casei Shirota (LcS) on gut microbiota composition, gut barrier integrity, intestinal inflammation and serum bile acid profile in metabolic syndrome. In a single-centre, prospective, randomised controlled pilot study, 28 subjects with metabolic syndrome received either LcS for 12 weeks (n = 13) or no LcS (n = 15). Data were compared to healthy controls (n = 16). Gut microbiota composition was characterised from stool using 454 pyrosequencing of 16S rRNA genes. Serum bile acids were quantified by tandem mass spectrometry. Zonulin and calprotectin were measured in serum and stool by ELISA. Bacteroidetes/Firmicutes ratio was significantly higher in healthy controls compared to metabolic syndrome but was not influenced by LcS. LcS supplementation led to enrichment of Parabacteroides. Zonulin and calprotectin were increased in metabolic syndrome stool samples but not influenced by LcS supplementation. Serum bile acids were similar to controls and not influenced by LcS supplementation. Metabolic syndrome is associated with a higher Bacteroidetes/Firmicutes ratio and gut barrier dysfunction but LcS was not able to change this. LcS administration was associated with subtle microbiota changes at genus level.
Trial Registration
ClinicalTrials.gov NCT01182844 相似文献77.
78.
Astrid Schrammel Marion Mussbacher Sarah Winkler Guenter Haemmerle Heike Stessel Gerald Wölkart Rudolf Zechner Bernd Mayer 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2013,1831(11):1600-1608
Cardiac oxidative stress has been implicated in the pathogenesis of hypertrophy, cardiomyopathy and heart failure. Systemic deletion of the gene encoding adipose triglyceride lipase (ATGL), the enzyme that catalyzes the rate-limiting step of triglyceride lipolysis, results in a phenotype characterized by severe steatotic cardiac dysfunction. The objective of the present study was to investigate a potential role of oxidative stress in cardiac ATGL deficiency. Hearts of mice with global ATGL knockout were compared to those of mice with cardiomyocyte-restricted overexpression of ATGL and to those of wildtype littermates. Our results demonstrate that oxidative stress, measured as lucigenin chemiluminescence, was increased ~ 6-fold in ATGL-deficient hearts. In parallel, cytosolic NADPH oxidase subunits p67phox and p47phox were upregulated 4–5-fold at the protein level. Moreover, a prominent upregulation of different inflammatory markers (tumor necrosis factor α, monocyte chemotactant protein-1, interleukin 6, and galectin-3) was observed in those hearts. Both the oxidative and inflammatory responses were abolished upon cardiomyocyte-restricted overexpression of ATGL. Investigating the effect of oxidative and inflammatory stress on nitric oxide/cGMP signal transduction we observed a ~ 2.5-fold upregulation of soluble guanylate cyclase activity and a ~ 2-fold increase in cardiac tetrahydrobiopterin levels. Systemic treatment of ATGL-deficient mice with the superoxide dismutase mimetic Mn(III)tetrakis (4-benzoic acid) porphyrin did not ameliorate but rather aggravated cardiac oxidative stress. Our data suggest that oxidative and inflammatory stress seems involved in lipotoxic heart disease. Upregulation of soluble guanylate cyclase and cardiac tetrahydrobiopterin might be regarded as counterregulatory mechanisms in cardiac ATGL deficiency. 相似文献
79.
Cruciani F La Fratta R Trombetta B Santolamazza P Sellitto D Colomb EB Dugoujon JM Crivellaro F Benincasa T Pascone R Moral P Watson E Melegh B Barbujani G Fuselli S Vona G Zagradisnik B Assum G Brdicka R Kozlov AI Efremov GD Coppa A Novelletto A Scozzari R 《Molecular biology and evolution》2007,24(6):1300-1311
Detailed population data were obtained on the distribution of novel biallelic markers that finely dissect the human Y-chromosome haplogroup E-M78. Among 6,501 Y chromosomes sampled in 81 human populations worldwide, we found 517 E-M78 chromosomes and assigned them to 10 subhaplogroups. Eleven microsatellite loci were used to further evaluate subhaplogroup internal diversification. The geographic and quantitative analyses of haplogroup and microsatellite diversity is strongly suggestive of a northeastern African origin of E-M78, with a corridor for bidirectional migrations between northeastern and eastern Africa (at least 2 episodes between 23.9-17.3 ky and 18.0-5.9 ky ago), trans-Mediterranean migrations directly from northern Africa to Europe (mainly in the last 13.0 ky), and flow from northeastern Africa to western Asia between 20.0 and 6.8 ky ago. A single clade within E-M78 (E-V13) highlights a range expansion in the Bronze Age of southeastern Europe, which is also detected by haplogroup J-M12. Phylogeography pattern of molecular radiation and coalescence estimates for both haplogroups are similar and reveal that the genetic landscape of this region is, to a large extent, the consequence of a recent population growth in situ rather than the result of a mere flow of western Asian migrants in the early Neolithic. Our results not only provide a refinement of previous evolutionary hypotheses but also well-defined time frames for past human movements both in northern/eastern Africa and western Eurasia. 相似文献
80.
Xu Q Saikatendu KS Krishna SS McMullan D Abdubek P Agarwalla S Ambing E Astakhova T Axelrod HL Carlton D Chiu HJ Clayton T DiDonato M Duan L Elsliger MA Feuerhelm J Grzechnik SK Hale J Hampton E Han GW Haugen J Jaroszewski L Jin KK Klock HE Knuth MW Koesema E Miller MD Morse AT Nigoghossian E Okach L Oommachen S Paulsen J Reyes R Rife CL Schwarzenbacher R van den Bedem H White A Wolf G Hodgson KO Wooley J Deacon AM Godzik A Lesley SA Wilson IA 《Proteins》2007,69(2):433-439