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51.
Clones of Plumbago zeylanica were micropropagated using nodal culture. The application of random amplified polymorphic DNA (RAPD) in assessing the genetic integrity of the micropropagated plants was evaluated by polymerase chain reaction. Twenty arbitrary decamers were used to amplify genomic DNA from in vitro and in vivo plant material to assess the genetic fidelity. All RAPD profiles from micro-propagated plants were monomorphic and similar to those of field grown mother plants. No polymorphism was detected within the micropropagated plants. 相似文献
52.
53.
Human cytochrome P-450 PB-1: A multigene family involved in mephenytoin and steroid oxidations that maps to chromosome 10 总被引:4,自引:1,他引:3 下载免费PDF全文
R. R. Meehan J. R. Gosden D. Rout N. D. Hastie T. Friedberg M. Adesnik R. Buckland V. van Heyningen J. Fletcher N. K. Spurr J. Sweeney C. R. Wolf 《American journal of human genetics》1988,42(1):26-37
The cytochrome P-450 monooxygenase system possesses catalytic activity toward many exogenous compounds (e.g., drugs, insecticides, and polycyclic aromatic hydrocarbons) and endogenous compounds (e.g., steroids, fatty acids, and prostaglandins). Multiple forms of cytochrome P-450 with different substrate specificities have been isolated. In the present paper we report the isolation and sequence of a cDNA clone for the human hepatic cytochrome P-450 responsible for mephenytoin (an anticonvulsant) oxidation. The mephenytoin cytochrome P-450 is analogous to the rat cytochrome P-450 form termed PB-1 (family P450C2C). We also report that human PB-1 is encoded by one of a small family of related genes all of which map to human chromosome 10q24.1-10q24.3. The endogenous role of this enzyme appears to be in steroid oxidations. This cytochrome P-450 family does not correspond to any of the hepatic cytochrome P-450 gene families previously mapped in humans. 相似文献
54.
Length–weight relationship of three Cynoglossus species (C. puncticeps,C. lingua and C. lida) from Chilika lagoon,India 下载免费PDF全文
S. K. Karna D. K. Sahoo J. K. Seth D. Mohapatro A. K. Rout S. Panda B. C. Guru 《Zeitschrift fur angewandte Ichthyologie》2018,34(4):988-989
The present study provides length–weight relationship (LWR) of three fish species, Cynoglossus puncticeps (Richardson, 1846), Cynoglossus lingua Hamilton, 1822 and Cynoglossus lida (Bleeker, 1851) of family Cynoglossidae from Chilika lagoon (19°28′–19°54′N; 85°05′–85°38′E), India. A total of 147 specimens were sampled during March, July and October of 2017 from screen barrier nets (mesh 14 mm to 26 mm) locally called khonda jal operated by local fishermen. The estimated b values derived from the data sets as follows: 3.12 for C. puncticeps, 3.09 for C. lida, and 2.88 for C. lingua. 相似文献
55.
Characterization and optimization of the embryogenic response from in-vitro-cultured immature inflorescences of rice (Oryza sativa L. sub-species indica and japonica) are described. Histological and morphological analyses revealed that the parenchymatous ground tissue present in the region between the second whorl of sterile bracts and the base of the fertile bracts, the embryogenically competent region (ECR), was involved in the embryogenic response. Initial cell divisions within the ECR occurred in the vicinity of the pro-vascular regions of the spikelet. Continued cell divisions resulted in groups of proliferating units and each single proliferating unit was the product of a coordinated behavior of neighboring cells functioning as a morphogenic group. Further proliferation of this embryogenic tissue was due to the development of cambium-like tissue(s) often forming an embryogenic stratum which under optimal culture conditions produced plants at a high frequency. The morphogenic pathways governing plant regeneration from spikelets of the immature rice inflorescence were dependent upon the growth-regulator composition of the culture medium. Three different modes of plant regeneration were observed: (i) direct plant regeneration, (ii) plant regeneration with an intervening callus phase (prolific non-embryogenic growth associated with unorganized, loose and mucilaginous tissue), and (iii) plant regeneration without an intervening callus phase (compact embryogenie tissue with highly organized growth). The efficiency of plant regeneration, via somatic embryogenesis without an intervening callus phase, was increased by optimizing the culture conditions. In a two-step procedure, immature inflorescences of rice were first cultured on a conditioning medium supplemented with 2.0 mg · 1–1 2,4-dichlorophenoxyacetic acid + 1.5 mg · 1–1 kinetin + 0.75 mg · 1–1 -naphthaleneacetic acid for a period of two weeks. The conditioning medium, with the appropriate culture conditions, allowed redirection of partially differentiated cells of the ECR into embryogenically competent pro-embryogenic groups. Maturation of these pro-embryogenic groups was achieved by transferring them to an embryo proliferation medium, and plants could then be regenerated at a high frequency upon their transfer to the regeneration medium.Abbreviations CM
conditioning medium
- 2,4-D
2,4-dichlorophenoxyacetic acid
- ECR
embryogenically competent region
- NAA
-naphthaleneacetic acid
- SEM
scanning electron micrograph
Thanks are extended to Stephanie Lara, Barbara Bricks, Kay Robbinson-Beers, James Haudenshield, Dave Bayer and Gene Nester, for their invaluable help during the course of this research. The research was partly supported by the Rockefeller Foundation through the Rice Biotechnology program as a grant to W.J.L. and a Postdoctoral Fellowship to J.R.R. 相似文献
56.
Metabolic changes during rooting in stem cuttings of Casuarina equisetifolia L.: effects of auxin, the sex and the type of cutting on rooting 总被引:3,自引:0,他引:3
Rooting in terminal shoot and lateral shoot cuttings from 10-year-old elite trees of Casuarina equisetifolia L. in different sex groups was achieved after 20 days when the basal ends of the cuttings were dipped for 3 h in 20 ppm indole-3-butyric acid (IBA). Shoots derived from male plants rooted better than their female and monoecious counterparts, and the lateral shoots were more responsive to rooting than the terminal shoots. During rooting, the metabolic activities varied in both lateral shoot and terminal shoot cuttings derived from plants under different sex groups. Peroxidase and polyphenoloxidase activities were high during root initiation and showed a sharp decline thereafter. The polyphenoloxidase activity was higher in the lateral shoot than the terminal shoot cuttings. The rooted plantlets survived and established well in the field.Abbreviations IAA
indole-3-acetic acid
- IBA
indole-3-butyric acid
- NAA
1-naphthaleneacetic acid
- PVP
polyvinylpyrrolidone 相似文献
57.
The sequences of the 5' long-terminal repeat (LTR) and adjacent leader
regions of 27 full-length copia elements isolated from natural populations
of Drosophila melanogaster, D. simulans, and D. mauritiana are presented.
Phylogenetic analyses indicate that although D. melanogaster copia elements
are distinct from those of D. simulans and D. mauritiana, the elements of
these latter two species are not distinguishable from one another. LTRs and
adjacent 5' leader regions of elements isolated from D. simulans and D.
mauritiana are structurally similar to one another and carry substantial
deletional variation mapping to regions previously identified as being of
potential importance for copia expression.
相似文献
58.
Samson O. Obado Marc Brillantes Kunihiro Uryu Wenzhu Zhang Natalia E. Ketaren Brian T. Chait Mark C. Field Michael P. Rout 《PLoS biology》2016,14(2)
The nuclear pore complex (NPC) is responsible for nucleocytoplasmic transport and constitutes a hub for control of gene expression. The components of NPCs from several eukaryotic lineages have been determined, but only the yeast and vertebrate NPCs have been extensively characterized at the quaternary level. Significantly, recent evidence indicates that compositional similarity does not necessarily correspond to homologous architecture between NPCs from different taxa. To address this, we describe the interactome of the trypanosome NPC, a representative, highly divergent eukaryote. We identify numerous new NPC components and report an exhaustive interactome, allowing assignment of trypanosome nucleoporins to discrete NPC substructures. Remarkably, despite retaining similar protein composition, there are exceptional architectural dissimilarities between opisthokont (yeast and vertebrates) and excavate (trypanosomes) NPCs. Whilst elements of the inner core are conserved, numerous peripheral structures are highly divergent, perhaps reflecting requirements to interface with divergent nuclear and cytoplasmic functions. Moreover, the trypanosome NPC has almost complete nucleocytoplasmic symmetry, in contrast to the opisthokont NPC; this may reflect divergence in RNA export processes at the NPC cytoplasmic face, as we find evidence supporting Ran-dependent mRNA export in trypanosomes, similar to protein transport. We propose a model of stepwise acquisition of nucleocytoplasmic mechanistic complexity and demonstrate that detailed dissection of macromolecular complexes provides fuller understanding of evolutionary processes. 相似文献
59.
Victoria Walsh Kristen Little Ryan Wiegand Jonathan Rout LeAnne M. Fox 《PLoS neglected tropical diseases》2016,10(8)
BackgroundOver 1.1 billion people worldwide are at risk for lymphatic filariasis (LF), and the global burden of LF-associated lymphedema is estimated at 16 million affected people, yet country-specific estimates are poor.SignificanceThese data highlight the magnitude of lymphedema in LF-endemic areas and emphasize the need to develop robust estimates of numbers of individuals with lymphedema in order to identify the extent of lymphedema management services needed in these regions. 相似文献
60.