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101.
Elena Frati Abdel-Majid Khatib Philippe Front Andrej Panasyuk France Aprile Dragoslav R. Mitrovic 《Free radical biology & medicine》1997,22(7):1139-1144
The effect of photoexcited riboflavin (RF) on the viscosity of hyaluronic acid (HA) solutions has been investigated. UV irradiation of RF causes under aerobic conditions fragmentation of HA and a decrease in the viscosity of its solutions. A decrease of HA viscosity occurs in PO4-buffered solutions and is accelerated by high pH, Fe2+ (but much less so by Fe3+), certain metal chelators, and horseradish peroxidase (HRP); it is partially inhibited by catalase and less so by superoxide dismutase (SOD). The reactivity of the system was completely blocked by Tris, ethanol, aspirin, d-manitol, dimethylthiourea (DMTU), dimethylsulfoxide (DMSO), and sodium azide. These results indicate that the most likely chemical species involved in the reaction is the hydroxyl radical. Singlet oxygen (102) generation is suggested by the ability of NaN3 and DMSO to completely inhibit the reactivity of the system. These two agents, however, may also interact with OH√ radical, as well and suppress the reactivity of the system. H2O2 and
seem also to be produced in significant amounts, because catalase and SOD partially block the reactivity of the system. The effect of HRP may be due to hydrogen subtraction from HA and H2O2 reduction to water. Photoexcitation of RF may potentially occur in vitro and in vivo in the organs and tissues that are permeable to light, such as the eye or skin, and damage HA and other cell-matrix components causing inflammation and accelerating aging. © 1997 Elsevier Science Inc. 相似文献
102.
103.
M. Alltree R. Barraclough J. Bras E. Clifford-Jones J. M. France Margaret M. C. Gilchrist Evan Griffiths J. Hamlett J. B. Laine Mary E. Lloyd J. M. Marchant T. P. S. Powell E. G. Gerald Roberts C. E. Sissons A. M. L. Smith I. Ap. Thomas L. F. Tinckler R. S. Todd D. B. Whitehouse R. J. Whiting A. Williams 《BMJ (Clinical research ed.)》1974,3(5922):39-40
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105.
Models for predicting enteric methane emissions from dairy cows in North America,Europe, and Australia and New Zealand 总被引:3,自引:0,他引:3 下载免费PDF全文
Jayasooriya A. D. R. N. Appuhamy James France Ermias Kebreab 《Global Change Biology》2016,22(9):3039-3056
There are several models in the literature for predicting enteric methane (CH4) emissions. These models were often developed on region or country‐specific data and may not be able to predict the emissions successfully in every region. The majority of extant models require dry matter intake (DMI) of individual animals, which is not routinely measured. The objectives of this study were to (i) evaluate performance of extant models in predicting enteric CH4 emissions from dairy cows in North America (NA), Europe (EU), and Australia and New Zealand (AUNZ) and (ii) explore the performance using estimated DMI. Forty extant models were challenged on 55, 105, and 52 enteric CH4 measurements (g per lactating cow per day) from NA, EU, and AUNZ, respectively. The models were ranked using root mean square prediction error as a percentage of the average observed value (RMSPE) and concordance correlation coefficient (CCC). A modified model of Nielsen et al. (Acta Agriculturae Scand Section A, 63 , 2013 and 126) using DMI, and dietary digestible neutral detergent fiber and fatty acid contents as predictor variables, were ranked highest in NA (RMSPE = 13.1% and CCC = 0.78). The gross energy intake‐based model of Yan et al. (Livestock Production Science, 64 , 2000 and 253) and the updated IPCC Tier 2 model were ranked highest in EU (RMSPE = 11.0% and CCC = 0.66) and AUNZ (RMSPE = 15.6% and CCC = 0.75), respectively. DMI of cows in NA and EU was estimated satisfactorily with body weight and fat‐corrected milk yield data (RMSPE < 12.0% and CCC > 0.60). Using estimated DMI, the Nielsen et al. (2013) (RMSPE = 12.7 and CCC = 0.79) and Yan et al. (2000) (RMSPE = 13.7 and CCC = 0.50) models still predicted emissions in respective regions well. Enteric CH4 emissions from dairy cows can be predicted successfully (i.e., RMSPE < 15%), if DMI can be estimated with reasonable accuracy (i.e., RMSPE < 10%). 相似文献
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J France M D Hanigan C K Reynolds J Dijkstra L A Crompton J A Maas B J Bequette J A Metcalf G E Lobley J C MacRae D E Beever 《Journal of theoretical biology》1999,198(1):121-133
An isotope dilution model for partitioning leucine uptake by the liver of the lactating dairy cow is constructed and solved in the steady state. If assumptions ae made, model solution permits calculation of the rate of leucine uptake from portal and hepatic arterial blood supply, leucine export into the hepatic vein, leucine oxidation and transamination, and synthesis and degradation of hepatic constitutive and export proteins. The model requires the measurement of plasma flow rate through the liver in combination with leucine concentrations and plateau isotopic enrichments in arterial, portal and hepatic plasma during a constant infusion of [1-13C]leucine tracer. The model can be applied to other amino acids with similar metabolic fates and will provide a means for assessing the impact of hepatic metabolism on amino acid availability to peripheral tissues. This is of particular importance when considering the dairy cow and the requirements of the mammary gland for milk protein synthesis. 相似文献
108.
Kevin L. Schulte Daniel J. Friedman Titilope Dada Harvey L. Guthrey Edgard W. Costa Eric J. Tervo Ryan M. France John F. Geisz Myles A. Steiner 《Liver Transplantation》2024,14(10):2303367
Inverted metamorphic Ga0.3In0.7As photovoltaic converters with sub-0.60 eV bandgaps grown on InP and GaAs are presented. Threading dislocation densities are 1.3 ± 0.6 × 106 and 8.9 ± 1.7 × 106 cm−2 on InP and GaAs, respectively. The devices generate open-circuit voltages of 0.386 and 0.383 V, respectively, under irradiance producing a short-circuit current density of ≈10 A cm−2, yielding bandgap-voltage offsets of 0.20 and 0.21 V. Power and broadband reflectance measurements are used to estimate thermophotovoltaic (TPV) efficiency. The InP-based cell is estimated to yield 1.09 W cm−2 at 1100 °C versus 0.92 W cm−2 for the GaAs-based cell, with efficiencies of 16.8 versus 9.2%. The efficiencies of both devices are limited by sub-bandgap absorption, with power weighted sub-bandgap reflectances of 81% and 58%, respectively, the majority of which is assumed to occur in the graded buffers. The 1100 °C TPV efficiencies are estimated to increase to 24.0% and 20.7% in structures with the graded buffer removed, if previously demonstrated reflectance is achieved. These devices also have application to laser power conversion in the 2.0–2.3 µm atmospheric window. Peak laser power converter efficiencies of 36.8% and 32.5% are estimated under 2.0 µm irradiances of 1.86 and 2.81 W cm−2, respectively. 相似文献
109.
Betina M. Porcel France Denoeud Fred Opperdoes Benjamin Noel Mohammed-Amine Madoui Tansy C. Hammarton Mark C. Field Corinne Da Silva Arnaud Couloux Julie Poulain Michael Katinka Kamel Jabbari Jean-Marc Aury David A. Campbell Roxana Cintron Nicholas J. Dickens Roberto Docampo Nancy R. Sturm V. Lila Koumandou Sandrine Fabre Pavel Flegontov Julius Luke? Shulamit Michaeli Jeremy C. Mottram Balázs Sz??r Dan Zilberstein Frédéric Bringaud Patrick Wincker Michel Dollet 《PLoS genetics》2014,10(2)
Members of the family Trypanosomatidae infect many organisms, including animals, plants and humans. Plant-infecting trypanosomes are grouped under the single genus Phytomonas, failing to reflect the wide biological and pathological diversity of these protists. While some Phytomonas spp. multiply in the latex of plants, or in fruit or seeds without apparent pathogenicity, others colonize the phloem sap and afflict plants of substantial economic value, including the coffee tree, coconut and oil palms. Plant trypanosomes have not been studied extensively at the genome level, a major gap in understanding and controlling pathogenesis. We describe the genome sequences of two plant trypanosomatids, one pathogenic isolate from a Guianan coconut and one non-symptomatic isolate from Euphorbia collected in France. Although these parasites have extremely distinct pathogenic impacts, very few genes are unique to either, with the vast majority of genes shared by both isolates. Significantly, both Phytomonas spp. genomes consist essentially of single copy genes for the bulk of their metabolic enzymes, whereas other trypanosomatids e.g. Leishmania and Trypanosoma possess multiple paralogous genes or families. Indeed, comparison with other trypanosomatid genomes revealed a highly streamlined genome, encoding for a minimized metabolic system while conserving the major pathways, and with retention of a full complement of endomembrane organelles, but with no evidence for functional complexity. Identification of the metabolic genes of Phytomonas provides opportunities for establishing in vitro culturing of these fastidious parasites and new tools for the control of agricultural plant disease. 相似文献
110.
Cendrine Godet Estelle Cateau Blandine Rammaert Marine Grosset Gwenaël Le Moal Guillaume Béraud Jean Philippe Martellosio Xavier Iriart Jacques Cadranel France Roblot 《Mycopathologia》2017,182(7-8):709-713
Invasive fungal infection is a serious complication following allogeneic hematopoietic stem cell transplantation. Pulmonary infection due to Hormographiella aspergillata is an uncommon condition associated with a high mortality rate. The susceptibility of H. aspergillata to available antifungal agents is not well established. We report for the first time a case of H. aspergillata lung infection that responded poorly to conventional treatment with liposomal amphotericin B (LAmB; 3 mg kg?1 of body weight per day) with renal damage at higher posology (5 mg kg?1 of body weight per day), but improved rapidly after addition of nebulized LAmB to intravenous LAmB (3 mg kg?1 of body weight per day). Successful treatment of our patient using nebulized LAmB would be worth evaluating in cases refractory to standard treatment or when the reference treatment may not be extended due to interaction or side effects. 相似文献