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171.
In this paper, we concentrate on a comparison of plant and animal-parasitic nematodes, to gain insight into the factors that influence the acquisition of the drug resistance by nematodes. Comparing nematode parasite of domestic animals and cultivated plants, it appears that drug resistance threatens only domestic animal production. Does the paucity of report on nematicide field resistance reflect reality or, is nematicide resistance bypassed by other management practices, specific to cultivated plants (i.e. agricultural control)? First, it seems that selection pressure by treatments in plants is not as efficient as selection pressure in ruminants. Agronomic practices (i.e. sanitation, early planting, usage of nematodes resistant cultivar and crop rotation) are frequently used to control parasitic-plant nematodes. Although the efficiency of such measures is generally moderate to high, integrated approaches are developing successfully in parasitic-plant nematode models. Secondly, the majority of anthelmintic resistance cases recorded in animal-parasitic nematodes concern drug families that are not used in plant-parasitic nematodes control (i.e. benzimidazoles, avermectines and levamisole). Thirdly, particular life traits of parasitic-plant nematodes (low to moderate fecundity and reproductive strategy) are expected to reduce probability of appearance and transmission of drug resistance genes. It has been demonstrated that, for a large number of nematodes such as Meloidogyne spp., the mode of reproduction by mitotic parthenogenesis reduced genetic diversity of populations which may prevent a rapid drug resistance development. In conclusion, anthelmintic resistance develops in nematode parasite of animals as a consequence of an efficient selection pressure. Early detection of anthelmintic resistance is then crucial: it is not possible to avoid it, but only to delay its development in farm animal industry. 相似文献
172.
Domitilla Mandatori Caterina Pipino Pamela Di Tomo Valeria Schiavone Antonia Ranieri Sara Pantalone Sara Di Silvestre Nadia Di Pietrantonio Mariangela Ucci Carola Palmerini Paola Failli Natalia Di Pietro Assunta Pandolfi 《Journal of cellular physiology》2019,234(11):19761-19773
Vascular calcification (VC) is an active and cell-mediated process that shares many common features with osteogenesis. Knowledge demonstrates that in the presence of risk factors, such as hypertension, vascular smooth muscle cells (vSMCs) lose their contractile phenotype and transdifferentiate into osteoblastic-like cells, contributing to VC development. Recently, menaquinones (MKs), also known as Vitamin K2 family, has been revealed to play an important role in cardiovascular health by decreasing VC. However, the MKs' effects and mechanisms potentially involved in vSMCs osteoblastic transdifferentiation are still unknown. The aim of this study was to investigate the possible role of menaquinone-4 (MK-4), an isoform of MKs family, in the modulation of the vSMCs phenotype. To achieve this, vascular cells from spontaneously hypertensive rats (SHR) were used as an in vitro model of cell vascular dysfunction. vSMCs from Wistar Kyoto normotensive rats were used as control condition. The results showed that MK-4 preserves the contractile phenotype both in control and SHR-vSMCs through a γ-glutamyl carboxylase-dependent pathway, highlighting its capability to inhibit one of the mechanisms underlying VC process. Therefore, MK-4 may have an important role in the prevention of vascular dysfunction and atherosclerosis, encouraging further in-depth studies to confirm its use as a natural food supplement. 相似文献
173.
David E. Harrison Randy Strong Silvestre Alavez Clinton Michael Astle John DiGiovanni Elizabeth Fernandez Kevin Flurkey Michael Garratt Jonathan A. L. Gelfond Martin A. Javors Moshe Levi Gordon J. Lithgow Francesca Macchiarini James F. Nelson Stacey J. Sukoff Rizzo Thomas J. Slaga Tim Stearns John Erby Wilkinson Richard A. Miller 《Aging cell》2019,18(2)
To follow‐up on our previous report that acarbose (ACA), a drug that blocks postprandial glucose spikes, increases mouse lifespan, we studied ACA at three doses: 400, 1,000 (the original dose), and 2,500 ppm, using genetically heterogeneous mice at three sites. Each dose led to a significant change (by log‐rank test) in both sexes, with larger effects in males, consistent with the original report. There were no significant differences among the three doses. The two higher doses produced 16% or 17% increases in median longevity of males, but only 4% or 5% increases in females. Age at the 90th percentile was increased significantly (8%–11%) in males at each dose, but was significantly increased (3%) in females only at 1,000 ppm. The sex effect on longevity is not explained simply by weight or fat mass, which were reduced by ACA more in females than in males. ACA at 1,000 ppm reduced lung tumors in males, diminished liver degeneration in both sexes and glomerulosclerosis in females, reduced blood glucose responses to refeeding in males, and improved rotarod performance in aging females, but not males. Three other interventions were also tested: ursolic acid, 2‐(2‐hydroxyphenyl) benzothiazole (HBX), and INT‐767; none of these affected lifespan at the doses tested. The acarbose results confirm and extend our original report, prompt further attention to the effects of transient periods of high blood glucose on aging and the diseases of aging, including cancer, and should motivate studies of acarbose and other glucose‐control drugs in humans. 相似文献
174.
175.
Plant injury due to oxygen deficiency in the root environment of soilless culture: A review 总被引:9,自引:1,他引:8
The deficiency of oxygen concentration in root environment linked to waterlogging conditions caused important injuries for
plants. These effects could be reproduced by oxygen deficient nutrient solution. This bibliographical synthesis has been centered
on experimental results obtained on plants cultivated in soilless culture. This review paper presents a methodology used to
study oxygen depletion in a nutrient solution and to calculate root respiration rates. The main factors influencing root respiration
are reviewed as well as the consequences of oxygen deficiency on roots and shoots functioning. This study would not be complete
without some information on the main mechanisms of plant adaptation to oxygen deficiency. 相似文献
176.
Saulo M. Silvestre Joanna M. Setchell Bayron R. Calle-Rendón José J. de Toledo Renato R. Hilário 《American journal of primatology》2020,82(12):e23210
All Neotropical primates are arboreal and thus depend on forests for their survival. Arboreality puts many Neotropical primates at risk of extinction due to the high rates of deforestation in the tropics. We assessed the influence of vegetation structure and forest patch attributes on the occurrence of the threatened red-handed howler monkey (Alouatta belzebul) in an Amazonian savanna. Using a sample of 38 forest patches in a region of approximately 2000 km2 in the state of Amapá, northern Brazil, we used logistic regression to find the best predictors of the occurrence of A. belzebul. We assessed patch area, patch isolation, the proportion of seasonally flooded forest in the patch, the density of flooded area palms, forest height, canopy cover, and diameter at breast height of trees. Patch area and palm density were the best predictors of the occurrence of A. belzebul in forest patches, both having a positive effect on the probability of occurrence. Our results indicate that areas of flooded forest in forest patches may be keystone habitats for A. belzebul living in Amazonian savannas. The observed effect of palm density on A. belzebul suggests that this variable is useful for planning conservation actions, including the selection of areas for protection and management strategies for areas inhabited by this primate. 相似文献
177.
Margaux Olivier Olivier Da Ines Simon Amiard He?di Serra Chantal Goubely Charles I. White Maria E. Gallego 《The Plant cell》2016,28(1):74-86
Structure-specific endonucleases act to repair potentially toxic structures produced by recombination and DNA replication, ensuring proper segregation of the genetic material to daughter cells during mitosis and meiosis. Arabidopsis thaliana has two putative homologs of the resolvase (structure-specific endonuclease): GEN1/Yen1. Knockout of resolvase genes GEN1 and SEND1, individually or together, has no detectable effect on growth, fertility, or sensitivity to DNA damage. However, combined absence of the endonucleases MUS81 and SEND1 results in severe developmental defects, spontaneous cell death, and genome instability. A similar effect is not seen in mus81 gen1 plants, which develop normally and are fertile. Absence of RAD51 does not rescue mus81 send1, pointing to roles of these proteins in DNA replication rather than DNA break repair. The enrichment of S-phase histone γ-H2AX foci and a striking loss of telomeric DNA in mus81 send1 further support this interpretation. SEND1 has at most a minor role in resolution of the Holliday junction but acts as an essential backup to MUS81 for resolution of toxic replication structures to ensure genome stability and to maintain telomere integrity. 相似文献
178.
José M Bueno Juan C Cuevas José M Fiandor Silvestre García-Ochoa Federico Gómez de las Heras 《Bioorganic & medicinal chemistry letters》2002,12(2):121-124
A number of novel 3',4'-fused dioxolane and dioxane sordarin derivatives were synthesised for structure-activity relationship studies. Many of these derivatives exhibit high activity against Candida spp. and Cryptococcus neoformans. 相似文献
179.
Martins C. B. Ferreira O. Rosado T. Gallardo E. Silvestre S. Santos L. M. A. 《Biotechnology letters》2021,43(7):1487-1502
Biotechnology Letters - The interest in bioactive compounds from microalgae is increasing since they have medicinal and nutritional areas. The present work aims to evaluate the potential... 相似文献
180.
T. Debenest J. Silvestre M. Coste F. Delmas E. Pinelli 《Journal of applied phycology》2009,21(1):65-73
A new cell primo-culture method was developed for the benthic diatom community isolated from biofilm sampled in rivers. The
approach comprised three steps: (1) scraping biofilm from river pebbles, (2) diatom isolation from biofilm, and (3) diatom
community culture. With a view to designing a method able to stimulate the growth of diatoms, to limit the development of
other microorganisms, and to maintain in culture a community similar to the original natural one, different factors were tested
in step 3: cell culture medium (Chu No 10 vs Freshwater “WC” medium modified), cell culture vessel, and time of culture. The
results showed that using Chu No 10 medium in an Erlenmeyer flask for cell culture was the optimal method, producing enough
biomass for ecotoxicological tests as well as minimising development of other microorganisms. After 96 h of culture, communities
differed from the original communities sampled in the two rivers studied. Species tolerant of eutrophic or saprobic conditions
were favoured during culture. This method of diatom community culture affords the opportunity to assess, in vitro, the effects
of different chemicals or effluents (water samples and industrial effluents) on diatom communities, as well as on diatom cells,
from a wide range of perspectives. 相似文献