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971.
Emerging high-throughput approaches to analyze bioremediation of sites contaminated with hazardous and/or recalcitrant wastes 总被引:1,自引:0,他引:1
Sustainable development requires the promotion of environmental management and a constant search for new technologies to treat a wide range of aquatic and terrestrial habitats contaminated by increasing anthropogenic activities. Bioremediation, i.e. the elimination of natural or xenobiotic pollutants by living organisms, is an environmentally friendly and cost-effective alternative to physico-chemical cleanup options. However, the strategy and outcome of bioremediation in open systems or confined environments depend on a variety of physico-chemical and biological factors that need to be assessed and monitored. In particular, microorganisms are key players in bioremediation applications, yet their catabolic potential and their dynamics in situ remain poorly characterized. To perform a comprehensive assessment of the biodegradative potential of a contaminated site and efficiently monitor changes in the structure and activities of microbial communities involved in bioremediation processes, sensitive, fast and large-scale methods are needed. Over the last few years, the scientific literature has revealed the progressive emergence of genomic high-throughput technologies in environmental microbiology and biotechnology. In this review, we discuss various high--throughput techniques and their possible--or already demonstrated-application to assess biotreatment of contaminated environments. 相似文献
972.
973.
Phosphorylase kinase (PhK) is a large hexadecameric complex that catalyzes the phosphorylation and activation of glycogen phosphorylase (GP). It consists in four copies each of a catalytic subunit (gamma) and three regulatory subunits (alpha beta delta). Delta corresponds to endogenous calmodulin, whereas little is known on the molecular architecture of the large alpha and beta subunits, which probably arose from gene duplication. Here, using sensitive methods of sequence analysis, we show that the C-terminal domain (named domain D) of these alpha and beta subunits can be significantly related to calcineurin B-like (CBL) proteins. CBL are members of the EF-hand family that are involved in the regulation of plant-specific kinases of the CIPK/PKS family, and relieve autoinhibition of their target kinases by binding to their regulatory region. The relationship highlighted here suggests that PhK alpha and/or beta domain D may be involved in a similar regulation mechanism, a hypothesis which is supported by the experimental observation of a direct interaction between domain D of PhKalpha and the regulatory region of the Gamma subunit. This finding, together the identification of significant similarities of domain D with the preceding domain C, may help to understand the molecular mechanism by which PhK alpha and/or beta domain D might regulate PhK activity. 相似文献
974.
Among paintings of birds thought to have been bought in 1663 in Nuremberg by Francis Willughby, and now housed in Nottingham
University library, is the painting of a bird called Jangle de Languedoc. Unlike some of the other drawings, this particular
one was never used by Ray in his Ornithology of Francis Willughby (1678), who had difficulty in identifying the bird. We show here that this painting was not bought in Nuremberg, but that it was
obtained by Ray from Sir Thomas Crew, during his stay in Montpellier in 1665. Furthermore, had Ray looked at Gessner (Historiae animalium liber III qui est de avium natura. Christophus Froschoverus, Tiguri, 1555), Aldrovandi (Ornithologiae, tomus alter. Bononiae, apud Franciscum de Franciscis Senensem, 1600), Jonston (Historiae naturalis de avibus libri VI. Matthaeus Merianus, Frankfurt, 1650) and mostly at Charleton (Gualteri Charletoni Exercitationes de Differentiis & Nominibus Animalium. Theatro Sheldoniano, Oxford, 1677), he would have been able to identify the bird of the painting as alchata or “angel”, specifically a pintailed sandgrouse,
Pterocles alchata. 相似文献
975.
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
976.
The ultimate effect of being cleaned: does ectoparasite removal have reproductive consequences for damselfish clients? 总被引:1,自引:0,他引:1
The mutualistic nature of cleaning symbioses has long remainedunconfirmed because of the difficulty in showing net benefitsfor clients. We have previously shown that cleaning gobies (Elacatinusspp.) within territories of Caribbean longfin damselfish (Stegastesdiencaeus) reduce the number of gnathiid isopod ectoparasiteson territory owners. We now investigate whether this benefitof being cleaned has reproductive consequences for male longfindamselfish. The mating success, rate of egg loss, and parentalaggression of 40 nest-guarding males were assessed during sixconsecutive monthly reproductive periods. Ten males had cleaningstations within their territory, 10 males were without cleaningstations, and 20 males initially with a cleaning station hadtheir cleaners removed half-way through the study. Ectoparasiteloads on our focal fish were very low; however, damselfish withcleaning stations still had significantly fewer ectoparasitesthan did fish without cleaning stations. There was, however,no significant difference in the number of eggs, clutches, orarea of clutches received, or in the number of eggs lost beforehatching between damselfish with and without cleaners. We alsofound no difference in parental male aggression between damselfishwith and without cleaners. We conclude that although ectoparasiteremoval appears to have no direct consequence for reproduction,at least for the levels of infestations observed on our studysite, it may still affect other aspects of damselfish fitnesssuch as survival. 相似文献
977.
Sébastien Personnic Isabelle Domaizon Ursula Dorigo Lyria Berdjeb Stéphan Jacquet 《Hydrobiologia》2009,627(1):99-116
Flow cytometry (FCM) was used to assess microbial community abundances and patterns in three natural, large and deep peri-alpine
hydrosystems, i.e., lakes Annecy (oligotrophic), Bourget, and Geneva (mesotrophic). Picocyanobacteria, small eukaryotic autotrophs,
heterotrophic prokaryotes, and viruses were studied in the 0–50 m surface layers to highlight the impact of both physical
and chemical parameters as well as possible biotic interactions on the functioning of microbial communities. Some specificities
were recorded according to the trophic status of each ecosystem such as the higher number of viruses and heterotrophic bacteria
in mesotrophic environments (i.e., Lakes Geneva and Bourget) or the higher abundance of picocyanobacteria in the oligotrophic
Lake Annecy. However, both seasonal (temperature) and spatial (depth) variations were comparatively more important than the
trophic status in driving the microbial communities’ abundances in these three lakes, as revealed by principal component analysis
(PCA). A strong viral termination of the heterotrophic bacterial blooms could be observed in autumn for each lake, in parallel
to the mixing of the upper lit layers. As virus to bacteria ratio (VBR) was indeed very high at this period with values varying
between 87 and 114, such important relationships between viruses and bacteria were likely. The magnitudes of seasonal variations
in VBR, with the highest values ever reported so far, were largely greater than the magnitude of theoretical variations due
to the trophic status, suggesting also a strong seasonality in virioplankton production associated to prokaryotic dynamics.
FCM analyses allowed discriminating several viral groups. Virus-Like Particles group 1 (VLP1) and group 2 (VLP2) were always
observed and significantly correlated to bacteria for the former and chlorophyll a and picocyanobacteria for the latter, suggesting that most of VLP1 and VLP2 could be bacteriophages and cyanophages, respectively.
On the basis of these results, new ways of investigation emerge concerning the study of relationships between specific picoplanktonic
groups; and overall these results provide new evidence of the necessity to consider further viruses for a better understanding
of lake plankton ecology.
Handling editor: Luigi Naselli-Flores 相似文献
978.
Olivier Juffroy Danièle Noël Anne Delanoye Odile Viltart Isabelle Wolowczuk Claudie Verwaerde 《Differentiation; research in biological diversity》2009
Mesenchymal stem cells (MSC) are capable of both self-renewal and multi-lineage differentiation into mesoderm-type cells such as osteoblasts, chondrocytes, adipocytes and myocytes. Together the multipotent nature of MSCs and the facility to expand them in vitro make these cells ideal resources for regenerative medicine, particularly for bone reconstruction, and therefore research efforts focused on defining efficient protocols for directing their differentiation into the requisite lineage. Despite much progress in identifying mechanisms and factors that direct and control in vitro osteogenic differentiation of MSCs, a rapid and simple model to evaluate in vivo tissue formation is still lacking. Here, we describe the unique capacity of the murine bone marrow-derived D1 MSC cell line, which differentiates in vitro into at least three cell lineages, to form in vivo a structure resembling bone. This bone-like structure was obtained after subcutaneous grafting of D1 cells into immunocompetent mice without the need of neither an osteogenic factor nor scaffold material. These data allow us to propose this cell model as a tool for exploring in vivo the mechanisms and/or factors that govern and potentially regulate osteogenesis. 相似文献
979.
980.
Isabelle Brigaud Xavier Grosmaître Marie-Christine François Emmanuelle Jacquin-Joly 《Cell and tissue research》2009,335(2):455-463
In insects, biogenic amines have been shown to play an important role in olfactory plasticity. In a first attempt to decipher the underlying molecular mechanisms, we report the molecular cloning and precise expression pattern of a newly identified octopamine/tyramine-receptor-encoding gene in the antennae of the noctuid moth Mamestra brassicae (MbraOAR/TAR). A full-length cDNA has been obtained through homology cloning in combination with rapid amplification of cDNA ends/polymerase chain reaction; the deduced protein exhibits high identities with previously identified octopamine/tyramine receptors in other moths. In situ hybridization within the antennae has revealed that MbraOAR/TAR is expressed at the bases of both pheromone-sensitive and non-sensitive olfactory sensilla and in cells with a neurone-like shape. In accordance with previous physiological studies that have revealed a role of biogenic amines in the electrical activity of the receptor neurones, our results suggest that biogenic amines (either octopamine or tyramine) target olfactory receptor neurones to modulate olfactory coding as early as the antennal level. 相似文献