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61.
PURPOSE OF REVIEW: The aim of this article is to discuss the potential value of biomarkers for atherosclerosis in the assessment of risk for cardiovascular disease, in the pathogenesis of atherosclerosis, and in the monitoring of pharmacological treatment. RECENT FINDINGS: In an attempt to improve global cardiovascular risk prediction, considerable effort has been made in the discovery and characterization of soluble biomarkers which can go beyond the measure of total and LDL cholesterol levels. In particular, circulating molecules related to chronic inflammation have emerged as potential biomarkers for atherosclerosis. Evidence, obtained from in-vitro and in-vivo experimental models, has also documented that the majority of biomarkers play a pathological role in atherogenesis. Multiple screening of different biomarkers may therefore improve the assessment of risk, diagnosis, and prognosis for cardiovascular disease. In addition, soluble biomarkers have been shown to be modulated by hypolipidemic drugs and to be potentially useful in determining the clinical benefits of pharmacological therapies that do not alter serum lipid levels. SUMMARY: Altered levels of soluble biomarkers are associated with cardiovascular disease, and profiling of multiple biomarkers for atherosclerosis will be a useful indicator for better risk assessment, diagnosis, and prognosis, as well as monitoring pharmacological treatments for atherosclerosis. 相似文献
62.
Alberto Ordaz Mariana Sánchez Rodrigo Rivera Rafael Rojas Alejandro Zepeda 《Biodegradation》2017,28(1):81-94
A nitrifying consortium was kinetically, stoichiometrically and molecularly characterized via the in situ pulse respirometric method and pyrosequencing analysis before and after the addition of m-cresol (25 mg C L?1) in a sequencing batch reactor (SBR). Five important kinetic and stoichiometric parameters were determined: the maximum oxygen uptake rate, the maximum nitrification rate, the oxidation yield, the biomass growth yield, and the substrate affinity constant. An inhibitory effect was observed in the nitrification process with a recovery of this by up to eight SBR cycles after m-cresol was added to the system. However, full recovery of the nitrification process was not observed, as the maximum oxygen uptake rate was 25% lower than that of the previous operation without m-cresol addition. Furthermore, the pyrosequencing analyses of the nitrifying consortium after the addition of only two pulses of 25 mg C L?1 m-cresol showed an important microbial community change represented by a decrease in the nitrifying populations and an increase in the populations degrading phenolic compounds. 相似文献
63.
Carbohydrate metabolism and fruit quality are affected in frost-exposed Valencia orange fruit 总被引:1,自引:0,他引:1
María Lorena Falcone Ferreyra Valeria Perotti Carlos M. Figueroa Sergio Garrán Perla C. Anderson Daniel Vázquez Alberto A. Iglesias Florencio E. Podestá 《Physiologia plantarum》2006,128(2):224-236
Exposure of citrus fruit to frost often results in the development of freeze injury during their maturation in planta. This work was aimed to analyze changes in the biochemistry and enzymology of carbohydrate metabolism in freeze-injured orange fruit ( Citrus sinensis var. Valencia late) and the involvement of oxidative stress in frost damage. The activities of pyrophosphate-dependent phosphofructokinase, phosphoenolpyruvate carboxylase and several fermentative enzymes increased in frost-exposed (FE) fruit, while NADP-malic enzyme and the mitochondrial isoform of NAD-malate dehydrogenase showed a reduction in their activities. Western blot analysis indicated a correlation between activity levels and protein content. Respiration rate in whole fruit was reduced by 40%, whereas the flavedo showed a more pronounced decline (53%). Volatile compound (i.e. ethanol and acetaldehyde) content was significantly higher in FE fruit than in control, as was that of l -malate (three-fold). Additionally, FE fruit showed a marked decrease in the maturity index (24%) because of a higher titratable acidity (39%). Evidence is presented that oxidative stress is involved in freeze-induced damage of orange fruit, where oxidative damage to lipids and proteins, and a greater electrolyte leakage in the flavedo were also observed. The results suggest that freezing temperatures provoke a notable metabolic switch in citrus fruit toward a fermentative stage, resulting in low-quality fruits. 相似文献
64.
Fadhlaoui-Zid Karima Cossu Piero Sanna Daria Scarpa Fabio Lai Tiziana Castelli Alberto Casu Marco Maltagliati Ferruccio 《Hydrobiologia》2021,848(18):4225-4240
Hydrobiologia - Recent research hypothesised that the Siculo-Tunisian Strait might fit, at least for some species, the picture of a genetic transitional zone instead of a sharp genetic break... 相似文献
65.
66.
Can habitat characteristics shape vertebral morphology in dolphins? An example of two phylogenetically related species from southern South America 下载免费PDF全文
María Constanza Marchesi Matías Sebastián Mora Lida Elena Pimper Enrique Alberto Crespo Rae Natalie Prosser Goodall 《Marine Mammal Science》2017,33(4):1126-1148
Fast swimming pelagic cetacean species have osteological characteristics that promote a more stable spine in comparison to that of coastal species. The Peale's dolphin (Lagenorhynchus australis) and the hourglass dolphin (Lagenorhynchus cruciger) have a close phylogenetic relationship and are found in coastal and pelagic waters in the Southern Hemisphere, respectively. The aim of this work was to study the relationship between the vertebral column's morphology and its flexibility, across these species of contrasting habitats. Vertebral counts and multiple measurements of each vertebra were used to infer intervertebral flexibility. Bivariate plots and discriminant multivariate analyses were employed to compare each functional region along the vertebral column. Both species displayed a regionalization of the column into three stable regions and two flexible areas, which statistically differ in the proportion of the skeleton occupied in each species. While the Peale's dolphin has rounder vertebrae, associated with higher flexibility, the hourglass dolphin has disk‐shaped vertebrae and strongly inclined processes related to high stability. Although the species are closely related phylogenetically, vertebral morphology is influenced by a diverse set of ecological and behavioral factors, reflecting a high degree of vertebral plasticity within the genus. 相似文献
67.
68.
Marta Érica Saidel Karen C. dos Santos Luís F.P. Nagano Carlos Alberto Montanari Andrei Leitão 《Bioorganic & medicinal chemistry letters》2017,27(17):4001-4006
Phenotypic assays were performed in prostate cancer cell lines to describe the biological activity of PI3K-AKT-mTOR pathway inhibitors retrieved from the virtual screening initiative. These novel chemicals share in common the aminopyridine scaffold, hitting PC-3 cells in macromolar range, with selectivity index over fibroblast cell lines. Moreover, a preliminary study of the mode of action by flow cytometry assay pointed out that these compounds had a rapamycin-like response for the PI3K-AKT-mTOR pathway modulation. 相似文献
69.
María-Angustias Rivadeneyra Gabriel Delgado Miguel Soriano Alberto Ramos-Cormenzana Rafael Delgado 《Current microbiology》1999,39(1):53-57
We studied the precipitation of carbonates in 17 strains of moderately halophilic, Gram-positive cocci belonging to two species:
Marinococcus halophilus and Marinococcus albus, isolated from the Salar de Atacama (Chile). They were cultivated in solid and liquid laboratory media for 42 days at salt
concentrations (wt/vol) of 3%, 7.5%, 15%, and 20%. The bioliths precipitated were studied by X-ray diffraction and scanning
electron microscopy. M. halophilus formed crystals at each of the salt concentrations, with a maximum number of strains capable of precipitating carbonates
at 7.5% and 15% salt concentrations. M. albus did not precipitate at 20% and showed a maximum at 7.5%. This behavior is similar to that of other Gram-positive bacteria
and differs from that found in Gram-negative bacteria. The bioliths precipitated were spherical, generally isolated, with
a size of 10–100 μm, varying with salinity. They were of magnesium calcite (CO3 Ca1-x Mgx) with Mg content increasing with increasing salinity and Mg/Ca molar ratio of the culture medium. These results demonstrate
the active role played by M. halophilus and M. albus in the precipitation of carbonates.
Received: 3 November 1998 / Accepted: 9 March 1999 相似文献
70.
Barros-Battesti DM Onofrio VC Labruna MB Martins JR Guglielmone AA 《Systematic parasitology》2005,61(2):85-92
The species Amblyomma fuscum Neumann, 1907 is a rare tick found on the Neotropical Region, but it has not been recorded as a valid taxon in some lists proposed by current taxonomists. After a comparison between the Brazilian material of A. fuscum deposited in the Acari Collection of the Butantan Institute, São Paulo, Brazil, and the male type deposited in Leiden Museum of Natural History, The Netherlands, we confirm the taxonomic validity of A. fuscum and redescribe the adult specimens based on light and scanning electron microscope studies. 相似文献