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Francois Crampes Fabrice Marion‐Latard Alexia Zakaroff‐Girard Isabelle de Glisezinski Isabelle Harant Claire Thalamas Vladimir Stich Daniel Rivire Max Lafontan Michel Berlan 《Obesity (Silver Spring, Md.)》2003,11(2):247-256
Objective: The aim of this study was to determine how training modifies metabolic responses and lipid oxidation in overweight young male subjects. Research Methods and Procedures: Eleven overweight subjects were selected for a 4‐month endurance training program. Before and after the training period, they cycled for 60 minutes at 50% of their Vo 2max after an overnight fast or 3 hours after eating a standardized meal. Various metabolic and endocrine parameters, and respiratory exchange ratio values were evaluated. Results: Exercise‐induced plasma norepinephrine concentration increases were similar before and after training in fasted or fed conditions. After food intake, exercise promoted a decrease in plasma glucose and a higher increase in epinephrine than in fasting conditions. The increase in epinephrine after the meal was more marked after training (264 ± 32 vs. 195 ± 35 pg/mL). Training lowered the resting plasma nonesterified fatty acids. During exercise, changes in glycerol were similar to those found before training. Lipid oxidation during exercise was higher in fasting than in fed conditions (15.5 ± 1.4 vs. 22.3 ± 1.7 g/h). Training did not significantly increase fat oxidation when exercise was performed in fed conditions, but it did in fasting conditions (18.6 ± 1.4 vs. 27.2 ± 1.8 g/h). Discussion: Endurance training decreased plasma nonesterified fatty acids, cholesterol, and insulin concentrations. Training increased lipid oxidation during exercise, in fasting conditions, and not when exercise was performed after the meal. During exercise in overweight subjects, the fasting condition seems more suited to oxidizing fat and maintaining glucose homeostasis than a 3‐hour wait after a standard meal. 相似文献
54.
Stefan Stich Marion Haag Thomas Häupl Orhan Sezer Michael Notter Christian Kaps Michael Sittinger Jochen Ringe 《Cell and tissue research》2009,336(2):225-236
In situ tissue engineering is a promising approach in regenerative medicine, with the possibility that adult stem or progenitor
cells will be guided chemotactically to a tissue defect and subsequently differentiate into the surrounding tissue type. Mesenchymal
stem cells (MSC) represent attractive candidate cells. Chemokines such as CXCL12 (SDF-1α) chemoattract MSC, but little is
known about the molecular processes involved in the chemotaxis and migration of MSC. In this study, MSC recruitment by CXCL12
was investigated by genome-wide microarray analysis. The dose-dependent migration potential of bone-marrow-derived MSC toward
CXCL12 was measured in an in vitro assay, with a maximum being recorded at a concentration of 1,000 nM CXCL12. Microarray
analysis of MSC stimulated with CXCL12 and non-stimulated controls showed 30 differentially expressed genes (24 induced and
six repressed). Pathway analysis revealed 11 differentially expressed genes involved in cellular movement and cytokine-cytokine
receptor interaction, including those for migratory inducers such as the chemokines CXCL8 and CCL26, the leukocyte inhibitory
factor, secretogranin II, and prostaglandin endoperoxide synthase 2. These results were confirmed by real-time polymerase
chain reaction for selected genes. The obtained data provide further insights into the molecular mechanisms involved in chemotactic
processes in cell migration and designate CXCL12 as a promising candidate for in situ recruitment in regenerative therapies.
Stefan Stich and Marion Haag contributed equally to this work.
This study was supported by the Investitionsbank Berlin and the European Regional Development Fund (grant: 10128098), Deutsche
Forschungsgemeinschaft (grant: DFG SI 569/7–1), and the Bundesministerium für Bildung und Forschung (Bioinside: 13N9817). 相似文献
55.
Stich B Melchinger AE Piepho HP Heckenberger M Maurer HP Reif JC 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2006,113(6):1121-1130
Association mapping holds great promise for the detection of quantitative trait loci (QTL) in plant breeding populations. The main objectives of this study were to (1) adapt the quantitative pedigree disequilibrium test to typical pedigrees of inbred lines produced in plant breeding programs, (2) compare the newly developed quantitative inbred pedigree disequilibrium test (QIPDT) with the commonly employed logistic regression ratio test (LRRT), with respect to the power and type I error rate of QTL detection, and (3) demonstrate the use of the QIPDT by applying it to flowering data of European elite maize inbreds. QIPDT and LRRT were compared based on computer simulations modeling 55 years of hybrid maize breeding in Central Europe. Furthermore, we applied QIPDT to a cross-section of 49 European elite maize inbred lines genotyped with 722 amplified fragment length polymorphism markers and phenotyped in four environments for days to anthesis. Compared to LRRT, the power to detect QTL was higher with QIPDT when using data collected routinely in plant breeding programs. Application of QIPDT to the 49 European maize inbreds resulted in a significant (P < 0.05) association located at a position for which a consensus QTL was detected in a previous study. The results of our study suggested that QIPDT is a promising QTL detection method for data collected routinely in plant breeding programs. 相似文献
56.
Predation impact of Cyclops vicinus on the rotifer community in Lake Constance in spring 总被引:1,自引:0,他引:1
The predation impact of Cyclops vicinus on rotifers was studiedunder near-natural conditions in small enclosures to evaluatewhether copepod predation is responsible for the decline ofrotifers in Lake Constance in spring. Cyclops vicinus fed selectivelyon Synchaeta spp.; Keratella and Polyarthra spp. were not selectedfor. Predation rates increased with prey density up to a maximumof 37 Synchueta day1 at a density of 1.6 x 106 Synchaetam2, i.e. at -1200 Synchaeta l1. Calculation ofcropping rates suggests that Cyclops alone can control the abundanceof Synchaeta in spring, i.e. that mainly Cyclops is responsiblefor the decline of Synchaeta species in Lake Constance in May. 相似文献
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S Gesta J Hejnova M Berlan D Daviaud F Crampes V Stich P Valet J S Saulnier-Blache 《Hormones et métabolisme》2001,33(12):701-707
The aim of the present study was to study the influence of fatty acids on the adrenergic control of lipolysis both in vitro and in vivo. Human subcutaneous adipose tissue explants were cultured for 48 h in the presence of 100 microM bromopalmitate (BrPal), and lipolysis was measured in isolated adipocytes. In control conditions, beta-AR-dependent activation of lipolysis by epinephrine was almost undetectable, and could be fully restored by pharmacological blockade of alpha2-AR-dependent antilipolysis. After BrPal treatment, epinephrine became fully lipolytic and was no longer influenced by alpha2-AR-blockade. Radioligand binding analysis revealed that BrPal treatment led to a significant reduction in the coupling of alpha2-AR to G proteins. In parallel, a chronic and significant increase in plasma fatty acids resulting from a 4-day high-fat diet (HFD) was accompanied by an impairment of the amplifying effect of the alpha2-AR antagonist phentolamine on exercise-induced lipolysis (measured in the subcutaneous adipose tissue with the use of a microdialysis probe) normally observed after a low-fat diet. In conclusion, in vitro and in vivo studies showed that fatty acids impair alpha2-AR-dependent antilipolysis. 相似文献
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HPLC-analysis of algal pigments: comparison of columns,column properties and eluents 总被引:1,自引:0,他引:1
The effects of columns (Nucleosil C18ODS, MZ-PAH, YMC-PACK C30), column properties (inner diameters of 4 mm, 3 mm and 2 mm, pore-width 10 nm and 30 nm) and eluents (methanol, acetonitrile,
acetone, water) were tested on the separation of algal pigments. The length of columns was 250 mm and particle size was 5
μm. Flow rates and gradients were adjusted to optimize peak separation; remaining chromatographic conditions were kept constant.
The resolution of chromatographic systems was tested with pigment standards and various algal cultures. Total flow rate and
retention times decreased with decreasing inner diameter, whereas pressure, sensitivity and peak-width increased. Pore width
had negligible effects on the chromatographic separation of pigments under the test conditions. Only with acetonitrile as
eluent were all the taxonomically important pigments resolved adequately: zeaxanthin (Cyanophyceae), lutein (Chlorophyceae),
fucoxanthin (Bacillariopyceae), alloxanthin (Cryptophyceae), peridinin (Dinophyceae). 相似文献