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521.
Transient and stable expression ofgusA fusions with rice genes in rice,barley and perennial ryegrass
522.
523.
Proteomic Characterization of Primary Mouse Hepatocytes in Collagen Monolayer and Sandwich Culture
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Malina Orsini Saskia Sperber Fozia Noor Esther Hoffmann Susanne N. Weber Rabea A. Hall Frank Lammert Elmar Heinzle 《Journal of cellular biochemistry》2018,119(1):447-454
Dedifferentiation of primary hepatocytes in vitro makes their application in long‐term studies difficult. Embedding hepatocytes in a sandwich of extracellular matrix is reported to delay the dedifferentiation process to some extent. In this study, we compared the intracellular proteome of primary mouse hepatocytes (PMH) in conventional monolayer cultures (ML) to collagen sandwich culture (SW) after 1 day and 5 days of cultivation. Quantitative proteome analysis of PMH showed no differences between collagen SW and ML cultures after 1 day. Glycolysis and gluconeogenesis were strongly affected by long‐term cultivation in both ML and SW cultures. Interestingly, culture conditions had no effect on cellular lipid metabolism. After 5 days, PMH in collagen SW and ML cultures exhibit characteristic indications of oxidative stress. However, in the SW culture the defense system against oxidative stress is significantly up‐regulated to deal with this, whereas in the ML culture a down‐regulation of these important enzymes takes place. Regarding the multiple effects of ROS and oxidative stress in cells, we conclude that the down‐regulation of these enzymes seem to play a role in the loss of hepatic function observed in the ML cultivation. In addition, enzymes of the urea cycle were clearly down‐regulated in ML culture. Proteomics confirms lack in oxidative stress defense mechanisms as the major characteristic of hepatocytes in monolayer cultures compared to sandwich cultures. J. Cell. Biochem. 119: 447–454, 2018. © 2017 Wiley Periodicals, Inc. 相似文献
524.
The Farnesoid X receptor (FXR) is a nuclear receptor activated by bile acids (BAs). BAs are amphipathic molecules that serve as fat solubilizers in the intestine under postprandial conditions. In the post-absorptive state, BAs bind FXR in the hepatocytes, which in turn provides feedback signals on BA synthesis and transport and regulates lipid, glucose and amino acid metabolism. Therefore, FXR acts as a homeostat of all three classes of nutrients, fats, sugars and proteins. Here we re-analyze the function of FXR in the perspective of nutritional metabolism, and discuss the role of FXR in liver energy homeostasis in postprandial, post-absorptive and fasting/starvation states.FXR, by regulating nutritional metabolism, represses autophagy in conditions of nutrient abundance, and controls the metabolic needs of proliferative cells. In addition, FXR regulates inflammation via direct effects and via its impact on nutrient metabolism. These functions indicate that FXR is an attractive therapeutic target for liver diseases. 相似文献
525.
Graeme I. Lancaster Katherine G. Langley Nils Anton Berglund Helene L. Kammoun Saskia Reibe Emma Estevez Jacquelyn Weir Natalie A. Mellett Gerard Pernes James R.W. Conway Man K.S. Lee Paul Timpson Andrew J. Murphy Seth L. Masters Steve Gerondakis Nenad Bartonicek Dominik C. Kaczorowski Marcel E. Dinger Mark A. Febbraio 《Cell metabolism》2018,27(5):1096-1110.e5
526.
Ruifang Li-Gao Renée de Mutsert Patrick C. N. Rensen Jan Bert van Klinken Cornelia Prehn Jerzy Adamski Astrid van Hylckama Vlieg Martin den Heijer Saskia le Cessie Frits R. Rosendaal Ko Willems van Dijk Dennis O. Mook-Kanamori 《Metabolomics : Official journal of the Metabolomic Society》2018,14(1):13
Introduction
Fasting metabolite profiles have been shown to distinguish type 2 diabetes (T2D) patients from normal glucose tolerance (NGT) individuals.Objectives
We investigated whether, besides fasting metabolite profiles, postprandial metabolite profiles associated with T2D can stratify individuals with impaired fasting glucose (IFG) by their similarities to T2D.Methods
Three groups of individuals (age 45–65 years) without any history of IFG or T2D were selected from the Netherlands Epidemiology of Obesity study and stratified by baseline fasting glucose concentrations (NGT (n?=?176), IFG (n?=?186), T2D (n?=?171)). 163 metabolites were measured under fasting and postprandial states (150 min after a meal challenge). Metabolite profiles specific for a high risk of T2D were identified by LASSO regression for fasting and postprandial states. The selected profiles were utilised to stratify IFG group into high (T2D probability?≥?0.7) and low (T2D probability?≤?0.5) risk subgroups. The stratification performances were compared with clinically relevant metabolic traits.Results
Two metabolite profiles specific for T2D (nfasting = 12 metabolites, npostprandial = 4 metabolites) were identified, with all four postprandial metabolites also being identified in the fasting state. Stratified by the postprandial profile, the high-risk subgroup of IFG individuals (n?=?72) showed similar glucose concentrations to the low-risk subgroup (n?=?57), yet a higher BMI (difference: 3.3 kg/m2 (95% CI 1.7–5.0)) and postprandial insulin concentrations (21.5 mU/L (95% CI 1.8–41.2)).Conclusion
Postprandial metabolites identified T2D patients as good as fasting metabolites and exhibited enhanced signals for IFG stratification, which offers a proof of concept that metabolomics research should not focus on the fasting state alone.527.
Biocontrolled soil nutrient distribution under the influence of an oxalogenic-oxalotrophic ecosystem
Sophie Pons Saskia Bindschedler David Sebag Pilar Junier Eric Verrecchia Guillaume Cailleau 《Plant and Soil》2018,424(1-2):145-156
Background and aims
Root phenology is important in controlling carbon and nutrient fluxes in terrestrial ecosystems, yet, remains largely unexplored, especially in the Arctic. We compared below- and aboveground phenology and ending of the growing season in two contrasting vegetation types of subarctic tundra: heath and meadow, and their response to experimental warming in autumn.Methods
Root phenology was measured in-situ with minirhizotrons and compared with aboveground phenology assessed with repeat digital photography.Results
The end of the growing season, both below- and aboveground, was similar in meadow and heath and the belowground growing season ended later than aboveground in the two vegetation types. Root growth was higher and less equally distributed over time in meadow compared to heath. The warming treatment increased air and soil temperature by 0.5 °C and slightly increased aboveground greenness, but did not affect root growth or prolong the below- and aboveground growing season in either of the vegetation types.Conclusions
These results imply that vegetation types differ in root dynamics and suggest that other factors than temperature control autumnal root growth in these ecosystems. Further investigations of root phenology will help to identify those drivers, in which including responses of functionally contrasting vegetation types will help to estimate how climate change affects belowground processes and their roles in ecosystem function.528.
Saskia H. M. van Erp Brian Dixon Felipe Figueroa Egbert Egberts René J. M. Stet 《Immunogenetics》1996,44(1):49-61
In this study we report the finding of three representatives of a new group of major histocompatibility complex class I sequences
in carp: Cyca-12 (Cyca-UA1
*
01), a full-length cDNA; Cyca-SP1 (Cyca-UAW1), a polymerase chain reaction (PCR) fragment from cDNA; and Cyca-G11 (Cyca-UA1
*
02), a partial genomic clone. Comparison of the amino acid sequences of Cyca-12, Cyca-SP1, and Cyca-G11 with classical and non-classical class I sequences from other species shows considerable conservation in regions that
have been shown to be involved in maintaining the structure and function of class I molecules. The genomic organization of
Cyca-12 has been elucidated by analysis of a partial genomic clone Cyca-G11, in combination with PCR amplifications on genomic DNA of a homozygous individual. Although the genomic organization
is similar to that found in class I genes from other species, the 3′ untranslated region contains an intron which is unprecedented
in class I genes, and intron 2 is exceptionally large (±14 kilobases). Southern blot analysis indicates the presence of multiple
related sequences. In phylogenetic analyses, the Cyca-UA sequences cluster with class I genes from zebrafish and Atlantic salmon, indicating that the ancestral gene arose before
the salmonid/cyprinid split, approximately 120 – 150 million years ago. The previously reported class I Cyca-Z genes from carp and Caau-Z genes from goldfish cluster as a completely separate lineage. A polyclonal antiserum (anti-Cyca12) was raised against a recombinant fusion protein containing most of the extracellular domains of Cyca-12. The antibodies showed substantial reactivity to the recombinant protein and an M
r
45 000 protein in membrane lysates of spleen and muscle, as well as to determinants present on leucocytes in fluorescence-activated
cell sorter analyses. Erythrocytes and thrombocytes were found to be negative.
Received: 6 November 1995 / Revised: 16 January 1996 相似文献
529.
Saskia Swart Trudy J. J. Logman Ben J. J. Lugtenberg Gerrit Smit Jan W. Kijne 《Archives of microbiology》1994,161(4):310-315
The chvB gene of Agrobacterium tumefaciens encodes a 235 kDa proteinaceous intermediate involved in the synthesis of -1,2-glucan. chvB mutants show a pleiotropic phenotype. Besides not to produce cyclic -1,2-glucan, chvB mutants have been reported to be avirulent, attachment-deficient, and nonmotile. In this study we report additional differences from the parent strain, probably all linked to changes in the cell envelope. This pleiotropic phenotype — except for attachment and virulence — could largely be prevented by growing chvB cells with low levels of calcium. Although a role for -1,2-glucan in osmoadaptation has been proposed, the mode of action of -1,2-glucan is not known. We speculate that in A. tumefaciens -1,2-glucan stabilizes membranes, which would be important especially in hypotonic media containing calcium.Abbreviations Cb
carbenicillin
- Km
kanamycin
- TCA
trichloroacetic acid
- Kav
fraction of the stationary gel volume available for diffusion
- LPS
lipopolysaccharide
- SDS-PAGE
Sodium dodecyl sulphate polyacrylamide gel electrophoresis 相似文献
530.
Heleen M. van der Maas Eliza R. de Jong Saskia Rueb Lambert A. M. Hensgens Frans A. Krens 《Plant molecular biology》1994,24(2):401-405
Stable transformation of perennial ryegrass (Lolium perenne L.) was achieved by biolistic bombardment of a non embryogenic cell suspension culture, using the hpt and gusA gene. The transformation yielded on the average 5 callus lines per bombardment (1.4×106 cells). Stable integration of the genes into the plant genome was demonstrated by Southern analysis of DNA, isolated from hygromycin-resistant callus lines. The gusA reporter gene, which was regulated by the constitutive promoter of the rice gene GOS2, was expressed in both transient and stable transformation assays, indicating that this promoter is suitable for expression of a transferred gene in perennial ryegrass. Long-term GUS expression was observed in ca. 40% of the callus lines, whereas the other callus lines showed instability after 6 months and 1 year of culture. 相似文献