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81.
Giovanni Savettieri Rosa Guarneri Giuseppe Salemi Vincenzo La Bella Donatella Ferraro Salvatore Scondotto Federico Piccoli 《Neurochemical research》1990,15(8):773-776
[3H]Flunitrazepam (FNZ) binding to cortical neurons from fetal rat brain was investigated in vitro. The use of a synthetic medium specific for neurons made it possible to plot a developmental curve of3H-FNZ binding in an almost pure neuronal culture. Detectable specific binding was present in vitro at time 0 (that is, the 16th gestational day). A progressive increase of binding, due to an increment in the number of recognition sites, was observed on the subsequent days. The affinity of the specific binding sites to3H-FNZ was enhanced by the addition of exogenous GABA, whereas the density was not affected. 相似文献
82.
83.
Airborne pollen sampling in Toledo, Central Spain 总被引:2,自引:0,他引:2
Herminia García-Mozo Rosa Pérez-Badia Federico Fernández-González Carmen Galán 《Aerobiologia》2006,22(1):55-66
Toledo is one of the main tourist spots of Spain, attracting around two million visitors per year. Its geographical situation
in the vast and scarcely monitored Region of Castilla La Mancha and the high number of tourists (especially in the spring)
has resulted in the Spanish Aerobiology Network (REA) making this city a major study objective. Air monitoring studies carried
out using REA sampling procedures commenced in October 2002. Thirty-two pollen types were identified during the sampling period
(October 2002 to October 2004). The annual Pollen Index (PI) was 44124 for the agricultural year October 2002–October 2003,
and 29666 in the same period of 2003–2004. The most abundant taxa were, in decreasing order of dominance: Cupressaceae, Quercus, Poaceae, Populus, Olea, Urticaceae, Platanus, Pinus and Ulmus. Other, less well-represented pollen taxa included Salix, Alnus, Fraxinus and Tamarix, which were characteristic of riverside areas, and Morus, Artemisia and Chenopodiaceae. The presence of Castanea pollen grains originating from chestnut crops far away from the city was clearly an example of long-distance transport. The
highest concentrations of airborne pollen were detected from March to May and also in January, due to the flowering of Cupressaceae
species. In general, there was a correlation between pollen and meteorological parameters: a positive correlation with temperature
and a negative correlation with rainfall and humidity during the pre-peak period. A negative correlation between temperature
and some tree pollen taxa was detected in the principal pollen period correlation analysis due to their long pollination periods. 相似文献
84.
Determining the regulation of metabolic networks at genome scale is a hard task. It has been hypothesized that biochemical pathways and metabolic networks might have undergone an evolutionary process of optimization with respect to several criteria over time. In this contribution, a multi-criteria approach has been used to optimize parameters for the allosteric regulation of enzymes in a model of a metabolic substrate-cycle. This has been carried out by calculating the Pareto set of optimal solutions according to two objectives: the proper direction of flux in a metabolic cycle and the energetic cost of applying the set of parameters. Different Pareto fronts have been calculated for eight different "environments" (specific time courses of end product concentrations). For each resulting front the so-called knee point is identified, which can be considered a preferred trade-off solution. Interestingly, the optimal control parameters corresponding to each of these points also lead to optimal behaviour in all the other environments. By calculating the average of the different parameter sets for the knee solutions more frequently found, a final and optimal consensus set of parameters can be obtained, which is an indication on the existence of a universal regulation mechanism for this system.The implications from such a universal regulatory switch are discussed in the framework of large metabolic networks. 相似文献
85.
Sara Garcia‐Serrano Carolina Gutiérrez‐Repiso Montserrat Gonzalo Juan Garcia‐Arnes Sergio Valdes Federico Soriguer Vidal Perez‐Valero Miguel A. Alaminos‐Castillo Juan Francisco Cobos‐Bravo Francisco J. Moreno‐Ruiz Alberto Rodriguez‐Cañete Francisca Rodríguez‐Pacheco Eva Garcia‐Escobar Eduardo García‐Fuentes 《Obesity (Silver Spring, Md.)》2015,23(8):1607-1615
86.
Federico Giri Pablo Collins 《Biological journal of the Linnean Society. Linnean Society of London》2014,113(4):914-930
South America has been influenced by different geoclimatic events ever since its separation from Africa. The inland water fauna has evolved in response to the changing landscape. Currently, there are indications of variations in populations, occurring to different degrees that would indicate a clinal pattern in morphology. Among South America's fauna, the freshwater anomuran, Aegla, is an enigmatic group as a result of its endemicity and is composed of only one genus. Of all the species in this family, Aegla uruguayana has the broadest distribution. Its native habitats have been influenced by several marine transgressions during the Miocene–Quaternary Periods; thus, it is likely that their current distribution has been more recent. Its habitat spreads across a number of isolated basins and sub‐basins that display distinct degrees of isolation/connection, making clinal variation patterns in the morphology of this species possible. The present study aimed to evaluate the pattern of carapace shape variation in A. uruguayana and how it relates to the isolation and/or connection of populations from different basins and sub‐basins, allowing the determination of any extant clinal patterns. The specimens studied belong to 25 separate populations, representing all areas in which the species currently exists. A total of 523 crabs were analyzed. We identified 13 landmarks and four semi‐landmarks in the carapace. The aeglids were divided into seven size intervals to avoid an allometry effect. In each size category, shape relationships analyzed by principal component analysis suggest a geographical pattern corresponding to the distribution of the populations studied. An evaluation of covariation between body shape and geographical coordinates reveals a strong pattern and shows that population distribution had a significant effect on species morphology. Additionally, according to covariance analysis, the variation in shape was not associated with the environmental variables studied. We observed a clinal pattern throughout the species distribution, which could be attributed to genetic drift. It is possible that this process is being amplified by the geographical isolation of the basins, differences in environmental characteristics, and low dispersal ability. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 914–930. 相似文献
87.
Andrea M. Quiroga Federico J. Berli Daniela Moreno Juan B. Cavagnaro Rubén Bottini 《Journal of Plant Growth Regulation》2009,28(1):28-35
In many cultivars of Vitis vinifera periods of mild water stress during ripening are thought to increase grape quality for winemaking, even though yields may
be negatively affected. Because abscisic acid (ABA) is involved in the signaling of water stress in plants, we examine the
effects of the ABA signal being given without the concomitant water stress. ABA at 250 mg l−1 was sprayed weekly or biweekly from bud-burst until harvest onto the leaves of vineyard-grown plants of cv. Cabernet Sauvignon.
For ABA-treated plants berry yield per bunch and per plant was significantly increased (1.5- to 2.0-fold) across three consecutive
harvests (2005 through 2007). Number of berries per bunch and per plant was the primary basis for the significant crop increases,
although bunches per plant also tended to increase (1.1- to 1.3-fold) across all three harvests. Other parameters assessed
included number of internodes, shoot length, leaf area, leaf water potential at midday, photosynthesis, and stomatal conductance.
These parameters showed no significant change with ABA treatment, although shoot length tended to be reduced, as was leaf
area relative to control plants. The significantly increased fruit yields were thus accomplished without accompanying increases
in leaf photosynthesis and leaf areas. Juice at harvest had equal levels of sugars (Brix) and somewhat higher levels of anthocyanins
and total polyphenols relative to control values. The two latter trends continued for the resultant wine across two vintage
years. In conclusion, three seasons of experimental trials have demonstrated that ABA application can significantly enhance
yield per plant in the field-grown grape (cv. Cabernet Sauvignon) by favoring increased berry set without diminishing the
quality of the fruit for winemaking use. 相似文献
88.
Halberg F Cornélissen G Stoynev A Ikonomov O Katinas G Sampson M Wang Z Wan C Singh RB Otsuka K Sothern RB Sothern SB Sothern MI Syutkina EV Masalov A Perfetto F Tarquini R Maggioni C Kumagai Y Siegelova J Fiser B Homolka P Dusek J Uezono K Watanabe Y Wu J Prikryl P Blank M Blank O Sonkowsky R Schwartzkopff O Hellbrügge T Spector NH Baciu I Hriscu M Bakken E 《Neuro endocrinology letters》2003,24(6):479-498
89.
90.
Federico Sisti Julieta Fernández Andrés Cordero Adriana Casabuono Alicia Couto Daniela Hozbor 《Bioorganic & medicinal chemistry letters》2017,27(3):432-436
Bordetella bronchiseptica produces respiratory disease primarily in mammals including humans. Although a considerably amount of research has been generated regarding lipopolysaccharide (LPS) role during infection and stimulating innate and adaptive immune response, mechanisms involved in LPS synthesis are still unknown. In this context we searched in B. bronchiseptica genome for putative glycosyltransferases. We found possible genes codifying for enzymes involved in sugar substitution of the LPS structure. We decided to analyse BB3394 to BB3400 genes, closed to a previously described LPS biosynthetic locus in B. pertussis. Particularly, conservation of BB3394 in sequenced B. bronchiseptica genomes suggests the importance of this gene for bacteria normal physiology. Deletion of BB3394 abolished resistance to naive serum as described for other LPS mutants. When purified LPS was analyzed, differences in the LPS core structure were found. Particularly, a GalNA branched sugar substitution in the core was absent in the LPS obtained from BB3394 deletion mutant. Absence of GalNA in core LPS alters immune response in vivo but is able to induce protective response against B. bronchiseptica infection. 相似文献