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981.
Verónica V. Lia Lidia Poggio Viviana A. Confalonieri 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,119(6):1053-1067
The highland region or Northwestern Argentina (NWA) is one of the southernmost areas of native maize cultivation and constitutes
an expansion of the peruvian Andes sphere of influence. To examine the genetic diversity and racial affiliations of the landraces
cultivated in this area, 18 microsatellite markers were used to characterize 147 individuals from 6 maize races representative
of traditional materials. For the whole data set, a total of 184 alleles were found, with an average of 10.2 alleles per locus.
The average gene diversity was 0.571. The observed patterns of genetic differentiation suggest that historical association
is probably the main factor in shaping population structure for the landraces studied here. In agreement with morphological
and cytogenetic data, Bayesian analysis of NWA landraces revealed the occurrence of three main gene pools. Assessment of racial
affiliations using a combined dataset including previous data on American landraces showed a clear relationship between one
of these gene pools and typical Andean races, whereas the remaining two gene pools exhibited a closer association to Caribbean
accessions and native germplasm from the United States, respectively. These results highlight the importance of integrating
regional genetic studies if a deeper understanding of maize diversification and dispersal is to be achieved. 相似文献
982.
Todd K. Shackelford Viviana A. Weekes-Shackelford Gregory J. LeBlanc April L. Bleske Harald A. Euler Sabine Hoier 《Human nature (Hawthorne, N.Y.)》2000,11(3):299-306
Female coital orgasm may be an adaptation for preferentially retaining the sperm of males with “good genes.” One indicator of good genes may be physical attractiveness. Accordingly, R. Thornhill, S. W. Gangestad, and R. Comer (1995) found that women mated to more attractive men reported an orgasm during a greater proportion of copulations than did women mated to less attractive men. The current research replicates this finding, with several design variations. We collected self-report data from 388 women residing in the United States or in Germany. Results support the hypothesis that women mated to more attractive men are more likely to report an orgasm at the most recent copulation than are women mated to less attractive men, after statistically controlling for several key variables. Discussion addresses (a) the inability of the present research to specify the causal link between female orgasm and male attractiveness and (b) the proactive nature of female sexuality documented in recent research guided by an evolutionary perspective. 相似文献
983.
984.
Intraspecific variability in Antarctic tintinnids: the Cymatocylis affinis/convallaria species group
Boltovskoy Demetrio; Dinofrio Estela O.; Alder Viviana A. 《Journal of plankton research》1990,12(2):403-413
Analyses of the morphometry of 630 loricae belonging to thedescribed species Cymatocylis affinis and Cymatocylis convallariaretrieved from 21 samples collected in the Weddel Sea (6O73?S)strongly suggest that both taxa, including the four formae intowhich C.affinis was originally divided, are members of a singlespecies. The only feature which varies significantly and consistentlyamong the samples surveyed is the total length of the lorica,lowest average lengths being positively correlated with lowestabsolute abundances of this tintinnid in the waters sampled.This relationship points to some unfavorable factor(s) whichaffects both tintinnid reproduction/ survival and growth; thedata analysed suggest that drops in the availability of foodmight be responsible for the size (and abundance) variationsobserved. 相似文献
985.
The UFL-AG-286 cell line, established from embryonic tissue of the lepidopteran insect Anticarsia gemmatalis, has been identified as a good candidate to be used as a cellular substrate in the development of a process for in vitro
production of the Anticarsia gemmatalis multicapsid nucleopolyhedrovirus, a baculovirus widely used as bioinsecticide. In order to characterize the technological
properties of this cell line and evaluate its feasibility to use it for the large-scale production of Anticarsia gemmatalis multicapsid nucleopolyhedrovirus, UFL-AG-286 cells were adapted to grow as agitated suspension cultures in spinner-flasks.
Batch suspension cultures of adapted cells in serum-supplemented TC-100 medium grew with a doubling time of about 29 h and
reached a maximum cell density higher than 3.5 × 106 viable cells ml−1. At the end of the growth period glucose was completely depleted from the culture medium, but l-lactate was not produced. Amino acids, with the exception of glutamine, were only negligibly consumed or produced. In contrast
to other insect cell lines, UFL-AG-286 cells appeared to be unable to synthesize alanine as a metabolic way to dispose the
by-product ammonia. The synchronous infection of suspension cultures with Anticarsia gemmatalis multicapsid nucleopolyhedrovirus in the early to medium exponential growth phase yielded high amounts of both viral progenies
per cell and reduced the specific demands of UFL-AG-286 cells for the main nutrients. 相似文献
986.
Avian mothers can influence offspring phenotype through the deposition of different compounds into eggs, such as antibodies, hormones and antioxidants. The concentration of carotenoids in yolk is larger than in maternal plasma, suggesting an important role of these compounds for offspring development. Since carotenoids have to be acquired from the diet, they may be available in limiting amounts to the mothers. Here, we investigated the role of egg carotenoids for offspring growth by experimentally increasing the concentration of yolk lutein, the main carotenoid in great tit (Parus major) yolk. We subsequently measured body condition, oxidative stress, immune response, plumage colouration and fledging success. Lutein increased body mass soon after hatching and fledging success, but did not affect tarsus length, oxidative stress, immune response and plumage colouration. The higher content of yolk lutein could have increased body mass by reducing oxidative stress caused by high metabolic rates of rapidly growing embryos or by promoting cell differentiation and proliferation. The positive effect of lutein on fledging success seems to be mediated by its influence on body mass 3 days post-hatch, since these two traits were correlated. The finding that our treatment did not affect traits measured later in the nestling period, except for fledging success, suggests that yolk lutein has short-term effects that are essential to increase survival until fledging. Our study shows the positive effect of yolk lutein on offspring survival in the great tit, and therefore suggests an important role of carotenoid-mediated maternal effects. 相似文献
987.
988.
Viviana Teresa Orlandi Morten Rybtke Enrico Caruso Stefano Banfi Tim Tolker-Nielsen Paola Barbieri 《Biofouling》2014,30(8):883-891
Photodynamic therapy (PDT) combines the use of organic dyes (photosensitizers, PSs) and visible light in order to elicit a photo-oxidative stress which causes bacterial death. GD11, a recently synthesized PS belonging to the boron-dipyrromethene (BODIPY) class, was demonstrated to be efficient against planktonic cultures of Pseudomonas aeruginosa, causing a 7 log unit reduction of viable cells when administered at 2.5?μM. The effectiveness of GD11 against P. aeruginosa biofilms grown in flow-cells and microtiter trays was also demonstrated. Confocal laser scanning microscopy of flow-cell-grown biofilms suggests that the treatment has a biocidal effect against bacterial biofilm cells. 相似文献
989.
990.
Pablo Luis Santo-Orihuela Guillermo Carvajal María Inés Picollo Claudia Viviana Vassena 《Memórias do Instituto Oswaldo Cruz》2013,108(8):1031-1036
The aim of the present work was to study the deltamethrin susceptibility of eggs from
Triatoma infestans populations and the contribution of pyrethroid
esterases to deltamethrin degradation. Insects were collected from sylvatic areas,
including Veinte de Octubre and Kirus-Mayu (Bolivia) and from domiciliary areas,
including El Palmar (Bolivia) and La Pista (Argentina). Deltamethrin susceptibility
was determined by dose-response bioassays. Serial dilutions of deltamethrin (0.0005-1
mg/mL) were topically applied to 12-day-old eggs. Samples from El Palmar had the
highest lethal dose ratio (LDR) value (44.90) compared to the susceptible reference
strain (NFS), whereas the Veinte de Octubre samples had the lowest value (0.50).
Pyrethroid esterases were evaluated using 7-coumaryl permethrate (7-CP) on
individually homogenised eggs from each population and from NFS. The El Palmar and La
Pista samples contained 40.11 and 36.64 pmol/min/mg protein, respectively, and these
values were statistically similar to NFS (34.92 pmol/min/mg protein) and different
from Kirus-Mayu and Veinte de Octubre (27.49 and 22.69 pmol/min/mg protein,
respectively). The toxicological data indicate that the domestic populations were
resistant to deltamethrin, but no statistical contribution of 7-CP esterases was
observed. The sylvatic populations had similar LDR values to NFS, but lower 7-CP
esterase activities. Moreover, this is the first study of the pyrethroid esterases on
T. infestans eggs employing a specific substrate (7-CP). 相似文献