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101.
Citrus peel physicochemical attributes are considered the main components conferring partial or even total resistance to fruit fly (Diptera: Tephritidae) infestation. Fruit fly females adapt their ovipositional strategies to overcome such resistance. Here, we explored the effects of citrus species (Rutaceae) on the ovipositional behaviour of the South American fruit fly, Anastrepha fraterculus (Wiedemann), and on its immature development. Particularly, we investigated the effects of (1) citrus species on oviposition behaviour and immature development, (2) citrus species on oviposition preference and on the location of the eggs at different depth in the citrus peel, and (3) harvest season and post‐harvest storage time on oviposition behaviour and immature development in lemon. Citrus species influenced ovipositional behaviour and affected survival of immature stages. Females laid eggs in lemon [Citrus limon (L.) Burm.], orange [Citrus sinensis (L.) Osbeck], and grapefruit (Citrus paradisi Macfadyen). In orange and lemon, larvae were found dead close to the oviposition areas, suggesting chemically mediated resistance mechanisms. Under choice conditions, females preferred grapefruit over lemon and bigger clutches were found in the layers where embryonic development is favoured. Unsuitability of lemon as a medium to complete development was neither affected by harvest season nor by storage time of the fruit after harvest. The physical and chemical characteristics of the peel were distinctive to each citrus species and may have affected the specific levels of resistance of these citrus species to infestation by A. fraterculus.  相似文献   
102.
103.
分离美洲大蠊内生细菌并测定菌体的淀粉、纤维素降解酶活性及抑菌特性。对虫体表面消毒,以LB和高氏一号培养基分离虫体内部细菌并进行16S rRNA基因序列分析。变色圈法测定降解酶活性,抑菌圈法测定抑菌活性。结果共分离到11株细菌,4株属于链霉菌属(Streptomyces),6株分别属于肠杆菌属(Enterbacter)、变形菌属(Proteus)、肠球菌属(Enterococcus)、沙雷氏菌属(Serratia)、芽胞杆菌属(Bacillus)和漫游球菌属(Vagococcus)。另有1株菌在NCBI中与肠杆菌的相似度最高, 为95%,可能代表着一个潜在的新种。4株链霉菌均有淀粉和纤维素降解能力。有3株菌对青枯雷尔氏菌有抑制效果。研究结果表明,美洲大蠊内生菌具有某些功能,甚至含有尚未发现的新菌种,是重要的菌种资源。  相似文献   
104.
105.

Purpose

Ginseng (Araliaceae), demonstrates widespread biological effects because of its purported antioxidant and other properties. The present study was undertaken to investigate the effects of American ginseng root extract on glucose-induced oxidative stress and associated oxidative damage to human umbilical vein endothelial cells (HUVECs).

Methods

Following pretreatment with various concentrations of ginseng (alcoholic extract), HUVECs were incubated with various concentrations of d-glucose ranging from 5 to 25 mmol/l for 24 h. l-Glucose was used at a concentration of 25 mmol/l as a control.

Results

Glucose-induced oxidative stress detected by intracellular reactive oxygen species accumulation, superoxide anion generation and DNA damage in HUVECs were significantly prevented by ginseng. Treatment of HUVECs with ginseng further led to significant prevention of glucose-induced NF-κB activation. Glucose-induced increase in fibronectin (FN), EDB+FN (a splice variant of FN), endothelin-1 (ET-1) and vascular endothelial growth factor (VEGF) mRNAs and protein levels were also prevented by ginseng treatment.

Conclusion

These data indicate that American ginseng prevented glucose-induced damage in the HUVECs through its antioxidant properties.  相似文献   
106.
Allometry of secondary sexual traits has been the subject of recent debate, and the generality of positive allometry and its association with sexual selection have been recently questioned. Whereas some studies suggest an almost universal positive allometry for traits under sexual selection and isometry or a negative allometry for traits not under such pressure, other studies argue that this pattern results from the study of exaggerated (ornamental) traits. To answer the call for an examination of the allometry of less-exaggerated sexually selected traits, we have examined morphological data from 14 sexually dimorphic traits and six monomorphic traits from three anuran species. Although we found evidence of positive allometry in male secondary sexual traits of several species and populations, not all nonsexual traits were isometric or exhibited negative allometry. Furthermore, our results indicate that larger traits in the populations that we studied were not associated with greater allometric slopes. Therefore, our study is in line with the contention suggesting no specific kind of allometric pattern for sexual and nonsexual characters, and we can only advocate for further investigation of trait allometry and sexual selection to understand the complexity underlying the evolution of allometry in sexual traits.  相似文献   
107.
Del Río MG  Lanteri AA 《ZooKeys》2011,(102):51-63
A new monotypic genus of Naupactini (Coleoptera: Curculionidae), Obrieniolus del Río is described based on the new species Obrieniolus robustus del Río, endemic to Peru. This genus is easily recognized by the black, denuded and shiny integument, with imbricate microsculpture and the rounded body, with short, cordiform and moderately convex elytra. According to a cladistic analysis based on 69 continuous and discrete morphological characters, the new genus is the sister taxon of a group formed by Amitrus Schoenherr, Trichocyphus Heller, Amphideritus Schoenherr, Asymmathetes Wibmer & O'Brien and Galapaganus Lanteri. The paper includes habitus photographs, line drawings of genitalia, mouthparts, and other external features of taxonomic value, and a dichotomous key to the genera of Naupactini distributed in the South American Transition Zone.  相似文献   
108.
This article uses a Native Hawaiian example to raise difficult questions about the role and responsibility of non-Indigenous educators in teaching and supporting Indigenous studies. It challenges educators and educational researchers to think closely about how they might serve as allies in Indigenous struggles for self-determination.  相似文献   
109.
The aim of this study was to investigate the adaptations of protein metabolism to seasonal fasting in an actively wintering boreal carnivore. Fifty farm-bred male American minks Mustela vison were divided into a fed control group and four experimental groups fasted for 2, 3, 5 or 7 days. The responses of nitrogen metabolism to wintertime food deprivation were determined by measuring the rate of weight loss, the tissue total protein concentrations and the plasma amino acid, urea, ammonia, uric acid and total protein levels. The mink has relatively poor adaptations to food deprivation, as it is not able to prolong phase II of fasting with fat as the major metabolic fuel. Instead, the species has to derive a part of its energy requirements from the breakdown of body proteins. The end product of protein catabolism—urea— accumulates in its circulation, and the mink may not be able to recycle urea-N. Although the mink can still have a high body fat percent at the end of the 7-day fast, it appears to enter phase III of fasting with stimulated proteolysis during this period.  相似文献   
110.
The genetic relationships among male Lutzomyia (Nyssomyia) intermedia (Lutz & Neiva) (Diptera: Psychodidae) from three populations from the same endemic area of American cutaneous leishmaniasis (ACL) in the state of Rio de Janeiro, Brazil, were compared. The sandflies were collected in three ecologically different habitats: domestic, extra-domestic and sylvatic over a total range of 800 m. Three molecular markers were employed to assess population variation. Based on MLEE markers, it could not be concluded that the three populations do not belong to the same gene pool (F(st) = 0.005). No within-population departure from Hardy-Weinberg equilibrium was detected (P < 0.05) and they presented the same level of gene variation. The number of migrants (Nm) indicated that at least 50 individuals per generation migrated between the three habitats. RAPD-PCR markers revealed that, except for the primer five, all were polymorphic. Phenetic analysis of the genotypes showed the presence of two principal clusters corresponding to: (1) domestic plus extra-domestic and (2) sylvatic. Unique genotypes were observed in each population. The sylvatic population was the most polymorphic, showing the largest number of genotypes and low level of similarity between them. Three mtDNA gene markers were studied by SSCP analysis. The most frequent haplotype for each marker ranged in frequency from 60 to 87% and individuals with unique haplotypes varied from 1 to 5%. Interestingly, the SSCP analysis showed a low level of polymorphism within populations. The disagreement between the different molecular markers observed and the hypothesis that L. intermedia could be participating in the transmission cycle of Leishmania (Viannia) braziliensis in environments ranging from the interior of human dwellings to the forest, are discussed.  相似文献   
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