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301.
Dickkopf-1 antagonizes Wnt signaling independent of beta-catenin in human mesothelioma 总被引:6,自引:0,他引:6
Lee AY He B You L Xu Z Mazieres J Reguart N Mikami I Batra S Jablons DM 《Biochemical and biophysical research communications》2004,323(4):1246-1250
Dickkopf-1 (Dkk-1) is a secreted protein that acts as a potent inhibitor of the Wnt signal transduction pathway. It is thought that the antagonistic effect of Dkk-1 is specific to the canonical (Wnt/beta-catenin) pathway. In this study, we demonstrate that restoration of Dkk-1 expression suppresses cell growth and induces apoptotic cell death in beta-catenin-deficient mesothelioma cell lines H28 and MS-1. Furthermore, we found that a small-molecule inhibitor of JNK inhibited the apoptosis induced by Dkk-1 overexpression in these cells. Together, our data suggest that Dkk-1 may be able to antagonize Wnt signaling and exert its tumor suppressive effects through beta-catenin-independent non-canonical pathways (i.e., the Wnt/JNK pathway). 相似文献
302.
Won SJ Novillo A Custodia N Rie MT Fitzgerald K Osada M Callard IP 《Integrative and comparative biology》2005,45(1):72-80
Freshwater mussels, Elliptio complanata were collected froma reference and pollutant-impacted pond on Cape Cod, MA. Glutathione-S-transferase(GST) activity was measured in gill, hepatopancreas and foot.In addition, content of seven heavy metals were measured inwhole bodies. GST activity was significantly elevated in hepatopancreasand foot, as was whole body cadmium level in animals from thecontaminated site suggesting that these animals have been exposedto organic and inorganic contaminants. Sodium dodecyl acrylamidegel electrophoresis (SDS-PAGE) analysis showed putative vitellogeninswith molecular weight 180 and 205 kDa bands only in the ovary.In non-denatured gel electrophoresis ovarian extracts revealedtwo higher molecular weight bands at 550 and 700 kDa, whichwere reproductive stage specific. Western blotting of SDS-PAGEand non-denatured gels using the anti-scallop yolk-protein antibodyconfirmed the presence of cross-reacting bands of the same molecularweights in the ovary but not other tissues. Although severalexperiments involving steroid hormone exposure were done, nosignificant changes in vitellogenin protein levels were observed.However, using an anti-human ERß antibody, ERßpositive bands were observed both in female foot, and the ovary.No cross reactivity with the antibody was observed in hepatopancreas.Additional studies are required to resolve questions of vitellogeninregulation and the role of (xeno)estrogens in bivalve molluscs. 相似文献
303.
Genetic relationships among Hylocereus and Selenicereus vine cacti (Cactaceae): evidence from hybridization and cytological studies 总被引:1,自引:0,他引:1
BACKGROUND AND AIMS: Hylocereus and Selenicereus are native to tropical and sub-tropical America. Based on its taxonomic status and crossability relations it was postulated that H. megalanthus (syn. S. megalanthus) is an allotetraploid (2n = 4x = 44) derived from natural hybridization between two closely related diploid taxa. The present work aimed at elucidating the genetic relationships between species of the two genera. METHODS: Crosses were performed and the putative hybrids were analysed by chromosome counts and morphological traits. The ploidy level of hybrids was confirmed by fluorescent in situ hybridization (FISH) of rDNA sites. Genomic in situ hybridization (GISH) was used in an attempt to identify the putative diploid genome donors of H. megalanthus and an artificial interploid hybrid. KEY RESULTS: Reciprocal crosses among four diploid Hylocereus species (H. costaricensis, H. monacanthus (syn. H. polyrhizus), H. undatus and Hylocereus sp.) yielded viable diploid hybrids, with regular chromosome pairing. Reciprocal crosses between these Hylocereus spp. and H. megalanthus yielded viable triploid, pentaploid, hexaploid and aneuploid hybrids. Morphological and phenological traits confirm the hybrid origin. In situ detection of rDNA sites was in accord with the ploidy status of the species and hybrid studied. GISH results indicated that overall sequence composition of H. megalanthus is similar to that of H. ocamponis and S. grandiflorus. High sequence similarity was also found between the parental genomes of H. monacanthus and H. megalanthus in one triploid hybrid. CONCLUSIONS: The ease of obtaining partially fertile F1 hybrids and the relative sequence similarity (in GISH study) suggest close genetic relationships among the taxa analysed. 相似文献
304.
Kristine M. Molina Mayra L. Estrella Noemi Rivera‐Olmedo Christine Frisard Stephenie Lemon Milagros C. Rosal 《Obesity (Silver Spring, Md.)》2018,26(9):1474-1480
Objective
Evidence suggests discrimination increases the risk of obesity. The biopsychosocial model of racism posits that psychological factors such as depressive symptoms may link experiences of perceived interpersonal discrimination to obesity. This study tested whether self‐reported experiences of everyday discrimination were associated with adiposity indicators and whether depressive symptoms explained these associations.Methods
Cross‐sectional survey data of 602 Latino adults living in Lawrence, Massachusetts, from the Latino Health and Well‐being Project (2011‐2013) were used. Participants completed questionnaires assessing perceived everyday discrimination and depressive symptoms. Anthropometric measures (i.e., BMI and waist circumference [WC]) were obtained by trained staff. Structural equation modeling was employed to test for direct and indirect effects of perceived everyday discrimination on adiposity.Results
Perceived everyday discrimination was directly and positively associated with higher BMI and WC, independent of sociodemographic factors, physical activity, and stressful life events. Perceived everyday discrimination was not indirectly associated with BMI and WC through depressive symptoms. However, perceived everyday discrimination was associated with higher levels of depressive symptoms.Conclusions
Self‐reported everyday discrimination among Latino adults is associated with adiposity. Day‐to‐day interpersonal discrimination may be implicated in obesity disparities for Latino adults.305.
306.
Most grassland communities in agricultural landscapes comprise a mix of exotic and native plants, where grasses and forbs are disposed in low diversity patches conforming a heterogeneous matrix of vegetation. Within these “novel” ecosystems, woody encroachment is one of the principal causes of ecosystem degradation. Here, we examined the resistance to exotic woody establishment (Gleditsia triacanthos) into four different monospecific patches characteristics of old-field grasslands in Inland Pampa: an annual forb (Conium maculatum), an annual grass (Lolium multiflorum), and two perennial grasses (Cynodon dactylon and Festuca arundinacea). We evaluated the filter to tree recruitment by rodent seed removal and survival and growth of Gleditsia seedlings transplanted into undisturbed and disturbed microsites, within each patch. Beneath intact vegetation seed removal was an important biotic filter to woody establishment whereas disturbances facilitated seed survival in patches of perennial grasses. Patch identity affected tree growth, and Cynodon reduced the final biomass compared to forbs. Disturbance enhanced tree performance independently of patch type. After 2 years, tree survival was independent of disturbance and patch identity. As patch identity may regulate granivory and growth of tree saplings, community susceptibility or resistance to woody invasion rather than representing a static community attribute could vary according to the dynamic changes in the proportion of susceptible-resistant patches. Broadly, our work reinforces the concept that mechanisms regulating vegetation heterogeneity add a component of stochasticity to biotic resistance to community plant invasion. 相似文献
307.
308.
Fernando Díaz Ana Denisse Re Ariadna Sánchez Honorio Cruz Ricardo A. González L. Noemi Sánchez 《Marine and Freshwater Behaviour and Physiology》2013,45(6):365-374
Exposure to thermal stress was shown to have a significant effect on the osmotic pressure of the hemolymph, glucose levels, total count of hemocyte (TCH), and proPO activity in adult white shrimp Litopenaeus vannamei. Exposure of the shrimp to CTMax significantly increased the osmotic pressure of the hemolymph relative to the control group. In organisms reaching CTMax, temperature elicited a secondary stress response that included an increase in hemolymph glucose of 31?mg?mL?1. Metabolites in hemolymph such as cholesterol, acylglycerides, and total protein were not significantly affected by exposure to CTMax. CTMax exposure affected several immunological parameters causing decreases in TCH and proPO activity. We suggested that biomarkers such as osmolality, glucose levels, TCH, and proPO activity could be used as sensitive predictors of exposure to CTMax in white shrimp. 相似文献
309.
310.
Noemi Pavo Andras Jakab Maximilian Y. Emmert Georg Strebinger Petra Wolint Matthias Zimmermann Hendrik Jan Ankersmit Simon P. Hoerstrup Gerald Maurer Mariann Gy?ngy?si 《PloS one》2014,9(11)