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981.
982.
983.
Evelyne Jouvin-Marche Mariza Goncalves Morgado Nikolaus Trede Patrice N. Marche Dominique Couez Isabelle Hue Carine Gris Marie Malissen Pierre-André Cazenave 《Immunogenetics》1989,30(2):99-104
Genomic DNA from a large panel of inbred strains of mice were hybridized sequentially with 15 Vα, 2 Vδ, 1 Cα, and 1 Cδ probes. Most of the Vα probes detected a high degree of plymorphism and have allowed the definition of five mouse T-cell receptor α (Tcr
α) haplotypes. One of these haplotypes (Tcr
α
e
) appears to arise from a recombination between theTcr
α
b
andTcr
α
a
haplotypes, the latter being the most frequently found in the conventional inbred strains. This recombination event clearly
indicates that the members of at least 11 Vα subfamilies are not closely linked but highly interspersed with one another on chromosome 14. 相似文献
984.
Background
H-NS regulates the acid stress resistance. The present study aimed to characterize the H-NS-dependent cascade governing the acid stress resistance pathways and to define the interplay between the different regulators. 相似文献985.
Lucas Moreau Evelyne Thiffault Werner A. Kurz Robert Beauregard 《Global Change Biology Bioenergy》2023,15(9):1119-1139
Meeting climate change mitigation targets by 2050, as outlined in international pledges, involves determining optimal strategies for forest management, wood supply, the substitution of greenhouse gas-intensive materials and energy sources, and wood product disposal. Our study quantified the cumulative mitigation potential by 2050 of the forest sector in the province of Quebec, Canada, using several alternative strategies and assessed under what circumstances the sector could contribute to the targets. We used the Carbon Budget Model of the Canadian Forest Sector to project ecosystems emissions and sequestration of seven alternative and one baseline (business-as-usual [BaU]) forest management scenarios over the 2018–2050 period. Three baskets of wood products were used in a Harvested Wood Products model to predict wood product emissions. The mitigation potential was determined by comparing the cumulative CO2e budget of each alternative scenario to the BaU. The proportion of methane emissions from landfills (RCH4%) and the required displacement factor (RDF) to achieve mitigation benefits were assessed both independently and jointly. The fastest and most efficient way to improve mitigation outcomes of the forest sector of Quebec is to reduce end-of-life methane emissions from wood products. By reducing methane emissions, the RDF for achieving mitigation benefits through intensification strategies can be reduced from 1.2–2.3 to 0–0.9 tC/tC, thus reaching the current provincial mean DF threshold (0.9). Both a reduction and an increase in the harvested volume have the potential to provide mitigation benefits with adequate RCH4% and RDF. Increased carbon sequestration in ecosystems, innovations in long-lived wood products, and optimal substitution in markets offer potential avenues for the forest sector to contribute to mitigation benefits but are subject to significant uncertainties. Methane emission reduction at the end of wood product service life is emerging as a valuable approach to enhance mitigation benefits of the forest sector. 相似文献
986.
Circulating Cell-Free DNA from Colorectal Cancer Patients May Reveal High KRAS or BRAF Mutation Load
Florent Mouliere Safia El Messaoudi Celine Gongora Anne-Sophie Guedj Bruno Robert Maguy Del Rio Franck Molina Pierre-Jean Lamy Evelyne Lopez-Crapez Muriel Mathonnet Marc Ychou Denis Pezet Alain R Thierry 《Translational oncology》2013,6(3):319-IN8
Our data might suggest a very high variation in the proportion of malignant cells in colorectal tumors and/or low tumor cell clonogenicity. However, the direct relationship between these data and the proportion of malignant cells is currently uncertain as the mechanism of ccfDNA release determines the yield (necrosis, apoptosis, or active release). Therefore, interindividual comparison of the proportion of mutant allele determined from circulating DNA could appear somewhat more difficult to interpret; however, this parameter could be an efficient biomarker for monitoring or following up CRC patients and could be combined with size fraction analysis, as demonstrated in this study, to provide a deeper examination toward this goal. 相似文献
987.
Tyrosine hydroxylase expression and activity in the rat brain: differential regulation after long-term intermittent or sustained hypoxia. 总被引:3,自引:0,他引:3
Evelyne Gozal Zahoor A Shah Jean-Marc Pequignot Jacqueline Pequignot Leroy R Sachleben Maria F Czyzyk-Krzeska Richard C Li Shang-Z Guo David Gozal 《Journal of applied physiology》2005,99(2):642-649
Tyrosine hydroxylase, a hypoxia-regulated gene, may be involved in tissue adaptation to hypoxia. Intermittent hypoxia, a characteristic feature of sleep apnea, leads to significant memory deficits, as well as to cortex and hippocampal apoptosis that are absent after sustained hypoxia. To examine the hypothesis that sustained and intermittent hypoxia induce different catecholaminergic responses, changes in tyrosine hydroxylase mRNA, protein expression, and activity were compared in various brain regions of male rats exposed for 6 h, 1 day, 3 days, and 7 days to sustained hypoxia (10% O(2)), intermittent hypoxia (alternating room air and 10% O(2)), or normoxia. Tyrosine hydroxylase activity, measured at 7 days, increased in the cortex as follows: sustained > intermittent > normoxia. Furthermore, activity decreased in the brain stem and was unchanged in other brain regions of sustained hypoxia-exposed rats, as well as in all regions from animals exposed to intermittent hypoxia, suggesting stimulus-specific and heterotopic catecholamine regulation. In the cortex, tyrosine hydroxylase mRNA expression was increased, whereas protein expression remained unchanged. In addition, significant differences in the time course of cortical Ser(40) tyrosine hydroxylase phosphorylation were present in the cortex, suggesting that intermittent and sustained hypoxia-induced enzymatic activity differences are related to different phosphorylation patterns. We conclude that long-term hypoxia induces site-specific changes in tyrosine hydroxylase activity and that intermittent hypoxia elicits reduced tyrosine hydroxylase recruitment and phosphorylation compared with sustained hypoxia. Such changes may not only account for differences in enzyme activity but also suggest that, with differential regional brain susceptibility to hypoxia, recruitment of different mechanisms in response to hypoxia will elicit region-specific modulation of catecholamine response. 相似文献