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821.
The invasive plant Coreopsis lanceolata has established itself among various native vegetation types in Japan, but comparative studies of control effects among multiple
vegetation types invaded by this plant are few. In the present study, experiments involving vegetation cutting at different
frequencies were carried out on three vegetation types: Zoysia japonica dominant type (Zj), C. lanceolata dominant type (Cl) and Miscanthus sinensis dominant type (Ms). Responses of C. lanceolata to changes in cutting frequency varied with vegetation type. In Zj, the abundance of C. lanceolata increased when cutting was performed once or not at all, but tended to decrease when it was performed twice or thrice. In
Cl, cutting once increased C. lanceolata, but this species was reduced when other cutting frequencies were employed. In Ms, C. lanceolata increased linearly with cutting frequency. The number of inflorescences of C. lanceolata in the plots was negatively correlated with cutting frequency in Zj and Cl. In Ms, the flowering of C. lanceolata was sometimes observed when cutting was performed only once. The most effective way to suppress C. lanceolata was not necessarily the best way to recover the natives. In Zj, cutting once positively influenced the abundances of native
herbs, while cutting thrice or not at all tended to decrease them. In Cl and Ms, cutting thrice reduced the abundances of
native herbs, while other cutting frequencies tended to increase them. To control invasive plants and restore the invaded
vegetation effectively, the management approach should be changed flexibly in response to vegetation type, and careful monitoring
of both invasive and native plants is desirable. 相似文献
822.
An acaulis2-1 (acl2-1) mutant of Arabidopsis thaliana (L.) Heynh.was isolated and characterized. The mutant had inflorescencesof much reduced length. The defect was severer in lower internodesand was visible preferentially in type 2 metamers. The defectin the elongation of internodal cells of inflorescences wasattributable to a defect in the mechanism for elongation ofthese cells. The cortical microtubules (MTs) were analyzed inthe acl2 mutant, in a comparison with those of an acl1 mutantwhich was described earlier, but no changes were detected inamounts of MTs. In the type 2 and type 3 metamers, the defectin elongation in acl mutants was loosely correlated with a changein the orientation of MTs. Thus, the abnormal arrangement ofMTs appears to be one of the pleiotropic effects of acaulismutations. Genetic mapping was performed using molecular markers and theACL2 gene was located at 100 map units on chromosome 1.
1Present address: Institute of Molecular and Cellular Biosciences,The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo, 113 Japan
2Present address: Division of Biological Sciences, GraduateSchool of Science, Hokkaido University, Kita-ku, Sapporo, 060Japan 相似文献
823.
824.
Fukasawa Keita Mishima Yoshio Yoshioka Akira Kumada Nao Totsu Kumiko Osawa Takeshi 《Ecological Research》2016,31(4):493-493
In 2011, the Fukushima Daiichi Power Plant accident resulted in the evacuation of about 81,000 people from the evacuation zone, which suffered from high levels of radioactive contamination. Large-scale and long-term land abandonment can cause changes in species assemblages. Despite the extensive global attention this incident received, open and spatially-explicit datasets of mammal fauna from Fukushima remain quite limited. We established a continuous monitoring protocol using camera traps for mammals both inside and outside the evacuation zone; this paper presents our first dataset. These data represent the monitoring results from 45 camera traps from May 2014 to October 2014, including the location and actuation time of each camera, and the list of video records. After the publication of this initial data paper, we intend to continue monitoring until 2023 and the dataset will be hereafter updated with new observations. 相似文献
825.
Kumiko Sakai-Kato Eiko SaitoKeiko Ishikura Toru Kawanishi 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(19):1466-1470
Doxorubicin, a highly effective anticancer drug, produces severe side effect such as cardiotoxicity, which is mainly caused by its metabolite, doxorubicinol. While in vitro studies by measuring cellular concentration of doxorubicin have been reported, there have been no reports on measuring cellular concentration of the metabolites. In this report, we developed a sensitive and high-throughput method for measuring cellular concentrations of doxorubicin and its metabolites by ultra-high-performance liquid chromatography. The method achieved more than 96% recovery of doxorubicin and its metabolites from cell homogenates. Using simple separation conditions, doxorubicin and its three main metabolites, and the internal standard, were separated within 3 min. The method has a limit of quantification of 17.4 pg (32.0 fmol) injected doxorubicin. This high sensitivity enables the detection and intracellular quantification of doxorubicin and its metabolite, doxorubicinol, in cell homogenates, and its use will facilitate studies of the relationship between doxorubicin pharmacokinetics and therapeutic outcome. 相似文献