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931.
Ileana Vera‐Reyes Itandehui Juanita Erendira Esparza‐Arredondo Ricardo Hugo Lira‐Saldivar Carlos Alejandro Granados‐Echegoyen Rocío Alvarez‐Roman Alfonso Vsquez‐Lpez Gladys De los Santos‐Villarreal Enrique Díaz‐Barriga Castro 《Journal of Phytopathology》2019,167(7-8):461-469
In this research, the in vitro antimicrobial effect of zinc oxide (ZnO), copper oxide (CuO) and iron oxide (Fe2O3) nanoparticles (NPs)—with average sizes of 20, 46 and 30 nm, respectively—on the root rot disease caused by the fungus Fusarium oxysporum and on blight disease caused by the fungus Alternaria solani were studied. Also, bacterial diseases caused by Clavibacter michiganensis and Pseudomonas syringae that infects a wide range of plant species were assessed. Different concentrations of NPs (0, 100, 250, 500, 700 and 1,000 mg/L) were prepared on PDA agar or King's B medium in a complete randomized design with four replicates. According to the results, ZnO NPs exhibited an outstanding inhibitory effect against fungi and bacteria strains. The above results were associated with the smaller particle size. Fungi strains showed a differential sensitivity depending on the kind of NPs used. A. solani showed the highest sensitivity to ZnO NPs at 1,000 mg/L (99%), followed by CuO NPs at the same dose (95%). Fe2O3 NPs at all evaluated doses had no inhibitory effects on the mycelia growth of this strain, although F. oxysporum revealed greater effectiveness of the CuO NPs (96%) compared with ZnO NPs since it only inhibited 91% of the mycelial growth. The antibacterial activity was studied through optical density. C. michiganensis was found to be more sensitive to ZnO NPs because a lesser dose (700 mg/L) was required to reduce the bacterial growth (90%); in comparison, P. syringae required a dose of 1,000 mg/L to inhibit its growth (67%). CuO NPs displayed the smallest growth inhibition against the bacteria strains analysed. The antimicrobial effect of the metallic NPs that were assayed increased with higher doses. 相似文献
932.
Pedro Naves Helena Bragana Filomena Nbrega Carlos Valente 《Journal of Applied Entomology》2019,143(10):1200-1204
Eucalypts are among the most widely planted forest trees in the world, and outside their native Australian range, the main arthropod pests are sap‐sucking insects, defoliators, gall‐making insects and xylophagous beetles. We report on a new association between a polyphagous wood‐boring beetle and Tasmanian blue gum (Eucalyptus globulus Labill.) in Central Portugal. Unidentified wood‐boring insects were found attacking two three‐year‐old E. globulus trees showing signs of decline among otherwise healthy trees in a commercial plantation, in June 2018. Declining trees presented dead twigs and branches, and recently developed epicormic sprouts evident on the trunks. Insects emerging from logs were identified as Ambrosiodmus rubricollis (Eichhoff), a species native to eastern and southern Asia, with the taxonomic identification validated by molecular analysis. To our knowledge, this is the first record of A. rubricollis associated with a eucalypt species worldwide. It is not clear whether the beetles played any significant role on the decline of the trees, but Ambrosiodmus may be potential pests for several tree and shrub species in Europe, as these beetles can transport pathogenic fungi. 相似文献
933.
Rasoul Khosravi Mahmoud-Reza Hemami Teresa Luísa Silva José Carlos Brito 《Zoology in the Middle East.》2019,65(2):104-115
The Goitered Gazelle, Gazella subgutturosa, is the most widespread gazelle species in the Middle East and central Asia inhabiting desert and semi-desert habitats. Today it is threatened and its geographic range and population size have experienced significant decline in the last decades. In Iran, the remnant populations are confined to fragmented habitats. We aimed to characterise genetic diversity and phylogenetic status of the populations of Goitered Gazelle in Central Iran and to evaluate the potential effect of a historic population bottleneck on the genetic variation of today’s population. We used noninvasive sampling to uncover structure and level of genetic variation in a fragment of the cytochrome-b gene from 170 samples. Genealogical analyses were performed using HKY+I model and phylogenetic trees reconstructed using Bayesian inference and maximum likelihood. We found extremely low levels of genetic variation, with altogether only five haplotypes in samples from different populations. Overall haplotype diversity was 0.081 and nucleotide diversity 0.0003. The mean observed mismatch between any two sequences was 0.093 with the largest peak for small numbers. The mismatch distribution fit the model of population expansion and suggested that gazelles had experienced a sudden expansion. An unrooted median-joining network analysis of mtDNA haplotypes showed a star-like structure which few mutations steps separating the haplotypes from other regions. Our findings strengthen the urgency of preserving the species’ genetic diversity to prevent local extinction. 相似文献
934.
Small ruminants are generally classified as either browsers or frugivores. We compared intake and digestion in one browsing species, the pudu (Pudu pudu), body weight 9 kg, and three frugivorous species, the red brocket (Mazama americana), 20 kg, the bay duiker (Cephalophus dorsalis), 12 kg, and Maxwell's duiker (C. maxwellii), 9 kg. Rations comprised: a commercial grain and alfalfa pellet, a small amount of vegetables, and mixed hay. Across species, neutral-detergent fiber (insoluble fiber) consumed averaged 34.2 ± 2.6% of dry matter (DM) while the crude protein consumed averaged 16.1 ± 0.5% DM. Apparent DM digestion was similar in pudu (75.2 ± 4.7%), brocket (73.2 ± 1.1%), and Maxwell's duikers (73.0 ± 2.8%), and significantly lower (P = 0.0167) in bay duikers (67.1 ± 4.3%). There were significant differences among species in digestibilities of neutral-detergent fiber, hemicellulose, and cellulose, but they did not follow body size differences, since larger species were expected to show higher digestion coefficients for fiber compared to smaller species. The type of fiber fed may have influenced these results. Frugivores may be adapted to a diet of soluble fibers, as might be found in wild fruits, instead of the insoluble fibers in the diet fed. Passage trials were conducted on the two smallest species. The mean transit time for pudu was 29.9 ± 0.8 hr, and for the Maxwell's duiker was 42.2 ± 6.4 hr. © 1996 Wiley-Liss, Inc. 相似文献
935.
A biological affinities study based on frequencies of cranial nonmetric traits in skeletal samples from three cemeteries at predynastic Naqada, Egypt, confirms the results of a recent nonmetric dental morphological analysis. Both cranial and dental traits analyses indicate that the individuals buried in a cemetery characterized archaeologically as high status are significantly different from individuals buried in two other, apparently nonelite cemeteries and that the nonelite samples are not significantly different from each other. A comparison with neighbouring Nile Valley skeletal samples suggests that the high status cemetery represents an endogamous ruling or elite segment of the local population at Naqada, which is more closely related to populations in northern Nubia than to neighbouring populations in southern Egypt. © 1996 Wiley-Liss, Inc. 相似文献
936.
937.
938.
939.
Geraniol Averts Methotrexate-Induced Acute Kidney Injury via Keap1/Nrf2/HO-1 and MAPK/NF-κB Pathways
Nancy S. Younis Heba S. Elsewedy Tamer M. Shehata Maged E. Mohamed 《Current issues in molecular biology》2021,43(3):1741
Objectives: Geraniol, a natural monoterpene, is an essential oil component of many plants. Methotrexate is an anti-metabolite drug, used for cancer and autoimmune conditions; however, clinical uses of methotrexate are limited by its concomitant renal injury. This study investigated the efficacy of geraniol to prevent methotrexate-induced acute kidney injury and via scrutinizing the Keap1/Nrf2/HO-1, P38MAPK/NF-κB and Bax/Bcl2/caspase-3 and -9 pathways. Methods: Male Wister rats were allocated into five groups: control, geraniol (orally), methotrexate (IP), methotrexate and geraniol (100 and 200 mg/kg). Results: Geraniol effectively reduced the serum levels of creatinine, urea and Kim-1 with an increase in the serum level of albumin when compared to the methotrexate-treated group. Geraniol reduced Keap1, escalated Nrf2 and HO-1, enhanced the antioxidant parameters GSH, SOD, CAT and GSHPx and reduced MDA and NO. Geraniol decreased renal P38 MAPK and NF-κB and ameliorated the inflammatory mediators TNF-α, IL-1β, IL-6 and IL-10. Geraniol negatively regulated the apoptotic mediators Bax and caspase-3 and -9 and increased Bcl2. All the biochemical findings were supported by the alleviation of histopathological changes in kidney tissues. Conclusion: The current findings support that co-administration of geraniol with methotrexate may attenuate methotrexate-induced acute kidney injury. 相似文献
940.
A recycling system combining biofiltration and hydroponics was used for rearing glass eels. Growth rates varied between 0.1 and 1.4% of body weight per feeding day. A large range of mortalities (9.4—93 %) after two months was mainly due to ectoparasitic infections. 相似文献