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1.
Marie-Hélène Chaput Darasinh Sihachakr Georges Ducreux Dominique Marie Nasrine Barghi 《Plant cell reports》1990,9(8):411-414
In order to regenerate somatic hybrids, mesophyll protoplasts from a dihaploid potato, BF15 (H1), were electrofused with those from two other dihaploid clones, Aminca (H6) and Cardinal (H3). Determination of the ploidy level by flow cytometry showed that 10% of plants regenerated from the fusion experiment with BF15 + Aminca were diploids, 14% triploids, 63% tetraploids and very few were mixoploids or had a higher ploidy level. Using morphological markers and vigour in plant growth, we were able to recover a total of 24 somatic hybrid plants, respectively 20 and 4 hybrids (accounting for 12% and 13% of regenerants) from the fusions BF15 + Aminca and BF15 + Cardinal. Most of the somatic hybrids were at the expected tetraploid level (2n=4x=48). The hybrid nature was confirmed by examining isoenzyme patterns for malate dehydrogenase (MDH) and isocitrate dehydrogenase (ICD). 相似文献
2.
Catherine Curie Thierry Liboz Marie-Hélène Montané Dominique Rouan Michèle Axelos Bernard Lescure 《Plant molecular biology》1992,18(6):1083-1089
In Arabidopsis thaliana, the activation process of the A1 EF-1 gene depends on several elements. Using the GUS reporter gene, transient expression experiments have shown that mutations of upstream cis-acting elements of the A1 promoter, or the deletion of an intron located within the 5 non-coding region, similarly affect expression in dicot or monocot protoplasts. The results reported here strongly suggest that this 5 intron is properly spliced in Zea mays. We show that two trans-acting factors, specifically interacting with an upstream activating sequence (the TEF 1 box), are present in nuclear extracts prepared from A. thaliana, Brassica rapa, Nicotiana tabacum and Z. mays. In addition, a DNA sequence homologous to the TEF 1 box, found at approximately the same location within a Lycopersicon esculentum EF-1 promoter, interacts with the same trans-acting factors. Homologies found between the A. thaliana and L. esculentum TEF 1 box sequences have allowed us to define mutations of this upstream element which affect the interaction with the corresponding trans-acting factors. These results support the notion that the activation processes of A. thaliana EF-1 genes have been conserved among angiosperms and provide interesting data on the functional structure of the TEF 1 box. 相似文献
3.
Valérie Dufour Marie-Hélène Broihanne Claudia A. F. Wascher 《Ethology : formerly Zeitschrift fur Tierpsychologie》2020,126(2):153-164
In their natural environment, animals often make decisions crucial for survival, such as choosing the best patch or food, or the best partner to cooperate. The choice can be compared to a gamble with an outcome that is predictable but not certain, such as rolling a dice. In economics, such a situation is called a risky context. Several models show that although individuals can generally evaluate the odds of each potential outcome, they can be subject to errors of judgment or choose according to decision-making heuristics (simple decision rules). In non-human primates, similar errors of judgment have been reported and we have recently shown that they also use a decisional heuristics when confronted with a risky choice in an exchange task. This suggests a common evolutionary origin to the mechanisms underlying decision-making under risk in primates. However, whether the same mechanisms are also present in more distantly related taxa needs to be further investigated. Other social species, like corvids, are renowned for their advanced cognitive skills and may show similar responses. Here, we analyse data on corvids (carrion crows, hooded crows, common ravens and rooks) tested in a risky exchange task comparable to the one used in non-human primates. We investigated whether corvids could exchange according to the odds of success or, alternatively, whether they used a heuristic similar to the one used by non-human primates. Instead, most corvids chose a course of action (either a low or high exchange rate) that remained constant throughout the study. In general, corvids’ mean exchange rates were lower compared to non-human primates, indicating that they were either risk-adverse or that they do not possess the cognitive capabilities to evaluate odds. Further studies are required to evaluate the flexibility in exchange abilities of these birds in exchange abilities of these birds. 相似文献
4.
Muriel Gros-Balthazard Claire Newton Sarah Ivorra Marie-Hélène Pierre Jean-Christophe Pintaud Jean-Frédéric Terral 《PloS one》2016,11(3)
Investigating crop origins is a priority to understand the evolution of plants under domestication, develop strategies for conservation and valorization of agrobiodiversity and acquire fundamental knowledge for cultivar improvement. The date palm (Phoenix dactylifera L.) belongs to the genus Phoenix, which comprises 14 species morphologically very close, sometimes hardly distinguishable. It has been cultivated for millennia in the Middle East and in North Africa and constitutes the keystone of oasis agriculture. Yet, its origins remain poorly understood as no wild populations are identified. Uncultivated populations have been described but they might represent feral, i.e. formerly cultivated, abandoned forms rather than truly wild populations. In this context, this study based on morphometrics applied to 1625 Phoenix seeds aims to (1) differentiate Phoenix species and (2) depict the domestication syndrome observed in cultivated date palm seeds using other Phoenix species as a “wild” reference. This will help discriminate truly wild from feral forms, thus providing new insights into the evolutionary history of this species. Seed size was evaluated using four parameters: length, width, thickness and dorsal view surface. Seed shape was quantified using outline analyses based on the Elliptic Fourier Transform method. The size and shape of seeds allowed an accurate differentiation of Phoenix species. The cultivated date palm shows distinctive size and shape features, compared to other Phoenix species: seeds are longer and elongated. This morphological shift may be interpreted as a domestication syndrome, resulting from the long-term history of cultivation, selection and human-mediated dispersion. Based on seed attributes, some uncultivated date palms from Oman may be identified as wild. This opens new prospects regarding the possible existence and characterization of relict wild populations and consequently for the understanding of the date palm origins. Finally, we here describe a pipeline for the identification of the domestication syndrome in seeds that could be used in other crops. 相似文献
5.
Yves Gleize Fanny Mendisco Marie-Hélène Pemonge Christophe Hubert Alexis Groppi Bertrand Houix Marie-France Deguilloux Jean-Yves Breuil 《PloS one》2016,11(2)
The rapid Arab-Islamic conquest during the early Middle Ages led to major political and cultural changes in the Mediterranean world. Although the early medieval Muslim presence in the Iberian Peninsula is now well documented, based in the evaluation of archeological and historical sources, the Muslim expansion in the area north of the Pyrenees has only been documented so far through textual sources or rare archaeological data. Our study provides the first archaeo-anthropological testimony of the Muslim establishment in South of France through the multidisciplinary analysis of three graves excavated at Nimes. First, we argue in favor of burials that followed Islamic rites and then note the presence of a community practicing Muslim traditions in Nimes. Second, the radiometric dates obtained from all three human skeletons (between the 7th and the 9th centuries AD) echo historical sources documenting an early Muslim presence in southern Gaul (i.e., the first half of 8th century AD). Finally, palaeogenomic analyses conducted on the human remains provide arguments in favor of a North African ancestry of the three individuals, at least considering the paternal lineages. Given all of these data, we propose that the skeletons from the Nimes burials belonged to Berbers integrated into the Umayyad army during the Arab expansion in North Africa. Our discovery not only discusses the first anthropological and genetic data concerning the Muslim occupation of the Visigothic territory of Septimania but also highlights the complexity of the relationship between the two communities during this period. 相似文献
6.
Ehlinger Claire Dartevelle Pauline Zaet Abdurraouf Kurashige Yoshihito Haïkel Youssef Metz-Boutigue Marie-Hélène Marban Céline 《International journal of peptide research and therapeutics》2019,25(4):1679-1687
International Journal of Peptide Research and Therapeutics - The success of endodontic treatments depends on the elimination of intracanal pathogens. Since irrigation and instrumentation can only... 相似文献
7.
8.
Bouchra Harraki Pascale Guiraud Marie-Hélène Rochat Henri Faure Marie-Jeanne Richard Michelle Fussellier Alain Favier 《Biometals》1994,7(3):237-243
Radioactive zinc was used to study the effect of a binary parenteral nutrient solution, composed of amino acids and glucose, on zinc uptake by fibroblasts. The influence of addition of taurine, l-glutamine and of the increase in l-histidine content of the admixture was assessed. The pure mixture was highly toxic for cells and so it was diluted 1/5 in tyrode buffer with 2% albumin. As compared with cells incubated in the buffer containing albumin, zinc absorption was significantly higher (P < 0.05) in the presence of the amino acids of the mixture. Amino acids thus increased bioavailability by displacing zinc bound to albumin. When the histidine concentration in the nutrient medium (4.2 mm) was doubled, inhibition was noted after 30 min of incubation and zinc uptake thereafter remained comparable to that in histidine-free medium. The addition of glutamine (4.2 mm), usually not present in binary mixtures, resulted in significant differences as compared with glutamine-free control medium. Taurine (0.8 mm), led to a constant increase in zinc uptake by fibroblasts as compared with that obtained with taurine-free mixture. However, ultrafiltration showed that taurine was not able to displace zinc from albumin. 相似文献
9.
Andreas Hartmann Julia Muellner Niklaus Meier Helke Hesekamp Priscilla van Meerbeeck Marie-Odile Habert Aurélie Kas Marie-Laure Tanguy Merry Mazmanian Hervé Oya Nissen Abuaf Hafida Gaouar Sabrina Salhi Fanny Charbonnier-Beaupel Marie-Hélène Fievet Damien Galanaud Sophie Arguillere Emmanuel Roze Bertrand Degos David Grabli Lucette Lacomblez Cécile Hubsch Marie Vidailhet Anne-Marie Bonnet Jean-Christophe Corvol Michael Schüpbach 《PloS one》2016,11(9)
10.
Administration of recombinant human IL11 after supralethal radiation exposure promotes survival in mice: interactive effect with thrombopoietin 总被引:2,自引:0,他引:2
Van der Meeren A Mouthon MA Gaugler MH Vandamme M Gourmelon P 《Radiation research》2002,157(6):642-649
In the present study, we evaluated the therapeutic potential of recombinant human IL11 in lethally irradiated C57BL6/J mice exposed to gamma rays. IL11 administered for 5 consecutive days beginning 2 h after total-body irradiation with 8 or 9 Gy 60Co gamma rays resulted in a significant increase in 30-day survival. When IL11 was administered, only a slight improvement in the hematopoietic status (both blood cell counts and progenitor cells) was observed after an 8-Gy exposure, and no improvement in hematopoietic reconstitution was observed after 9 Gy total-body irradiation. The enhancement of fibrinogen in the plasma of irradiated animals suggested the importance of infections in the death of animals. IL11 was able to limit the increase in fibrinogen levels. However, prevention of bacterial infections by antibiotic treatment, although it delayed death, was ineffective in promoting survival either in placebo-treated and IL11-treated mice. IL11 was administered along with thrombopoietin (TPO) or bone marrow transplantation to limit the hematopoietic syndrome, in addition to antibiotic treatment. When IL11 was combined with TPO, a potent stimulator of hematopoiesis, the survival of animals which had been irradiated with 10 Gy 137Cs gamma rays was increased significantly compared to those treated with IL11 or TPO alone. Furthermore, an interactive effect of TPO and IL11 on hematopoietic reconstitution was observed. Similarly, IL11 in combination with bone marrow transplantation enhanced survival after 15 Gy 137Cs gamma rays. These data suggest that the effect of IL11 on the hematopoietic system is only moderate when it is used alone in supralethally irradiated mice but that the effect is improved in the presence of a hematopoietic growth factor or bone marrow transplantation. 相似文献