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191.
Expression of a subset of the Arabidopsis Cys(2)/His(2)-type zinc-finger protein gene family under water stress 总被引:12,自引:0,他引:12
The genes encoding Cys(2)/His(2)-type zinc-finger proteins constitute a large family in higher plants. To elucidate the functional roles of these types of protein, four different members of the gene family were cloned from Arabidopsis by PCR-aided methods. One was identical to the already reported gene STZ/ZAT10 and three were as yet unidentified genes, then designated AZF1 (Arabidopsis zinc-finger protein 1), AZF2 and AZF3. The AZF- and STZ-encoded proteins contain two canonical Cys(2)/His(2)-type zinc-finger motifs, separated by a long spacer. Three conserved regions, named B-box, L-box, and DNL-box, were also recognized outside the zinc-finger motifs, as in other members of the two-fingered Cys(2)/His(2)-type zinc-finger protein family. These four genes were positioned on the same branch of a phylogenetic tree constructed based on the zinc-finger motif sequences, suggesting their structural and functional relationship. RNA blot analysis showed that all four genes were mainly expressed in roots and at different levels in other organs. Expression of the four genes responded to water stress. High-salt treatment resulted in elevated levels of expression of all of these genes. Low-temperature treatment increased the expression levels of AZF1, AZF3, and STZ, but not AZF2. Only AZF2 expression was strongly induced by ABA treatment, where the time course of the induction was similar to that caused by high salinity. In situ localization showed that AZF2 mRNA accumulated in the elongation zone of the roots under the salt-stress condition. These results suggest that AZF1, AZF2, AZF3, and STZ are all involved in the water-stress response in an ABA-dependent or -independent pathway to regulate downstream genes. 相似文献
192.
Higashi T Miura K Kikuchi R Shimada K Hiyamizu H Ooi H Iwabuchi Y Hatakeyama S Kubodera N 《Steroids》2000,65(5):281-294
The characterization of new conjugated vitamin D metabolites in rat bile was performed using HPLC, liquid chromatography/tandem mass spectrometry combined derivatization, and GC-MS. After the administration of 24,25-dihydroxyvitamin D(3) to rats, 23, 25-dihydroxy-24-oxovitamin D(3) 23-glucuronide, 3-epi-24, 25-dihydroxyvitamin D(3) 24-glucuronide, and 24,25-dihydroxyvitamin D(3) 3-sulfate were obtained as new biliary metabolites together with 24,25-dihydroxyvitamin D(3) 3- and 24-glucuronides. The above metabolites, except 24,25-dihydroxyvitamin D(3) 3-glucuronide, were obtained from rats dosed with 25-hydroxyvitamin D(3). 23, 25-Dihydroxyvitamin D(3) 23-glucuronide was also obtained from the bile of rats administered 25-hydroxyvitamin D(3) in addition to its 3-glucuronide, 25-glucuronide, and 3-sulfate. Thus, it was found that 24,25-dihydroxyvitamin D(3) and 25-hydroxyvitamin D(3) were directly conjugated as glucuronide and sulfate, whereas at the C-23 position, they were hydroxylated and then conjugated. Furthermore, we found that the C-3 epimerization acts as one of the important pathways in vitamin D metabolism. 相似文献
193.
Kobayashi K Suzuki SI Izawa Y Miwa K Yamanaka S 《The Journal of General and Applied Microbiology》1998,44(1):85-91
We screened various Bacillus species producing transglutaminase (TGase), measured as labeled putrescine incorporated into N,N-dimethylcasein. As a result, we detected TGase activity in sporulating cells of B. subtilis, B. cereus, B. alvei and B. aneurinolyticus, and found TGase activity related to sporulation. TGase activity of Bacillus subtilis was detected in lysozyme-treated sporulating cells during late sporulation, but not in cells without lysozyme treatment or the supernatant of the culture broth. TGase was found to be localized on spores. TGase was preliminarily purified by gel filtration chromatography for characterization. Its activity was eluted in the fractions indicating a molecular weight of approximately 23 kDa. TGase could cross-link and polymerize a certain protein. The enzyme was strongly suggested to form epsilon-(gamma-glutamyl)lysine bonds, which were detected in the spore coat proteins of B. subtilis. The activity was Ca(2+)-independent like the TGases derived from Streptoverticillium or some plants. It is suggested that TGase is expressed during sporulation and plays a role in the assembly of the spore coat proteins of the genus Bacillus. 相似文献
194.
Takashi Araki Yasushi Kobayashi Hidetaka Kaya Masaki Iwabuchi 《Journal of plant research》1998,111(2):277-281
Transition from vegetative to reproductive development (flowering) is one of the most important decisions during the post-embryonic
development of flowering plants. More than twenty loci are known to regulate this process inArabidopsis. Some of these flowering-time genes may act at the shoot apical meristem to regulate its competence to respond to floral
inductive signals and floral evocation. Genetic and phenotypic analyses of mutants suggest that the late-flowering geneFT may be a good candidate for such genes. To test this, we have cloned theFT gene using aFT-deficiency line associated with a T-DNA insertion. Cloned genes and loss-of-function mutants in hand, it is now possible
to analyse the role ofFT and other genes in flowering at the biochemical and cellular levels as well as at the genetic level. The deduced FT protein
has homology with TFL1 and CEN proteins believed to be involved in regulation of inflorescence meristem identity. Phylogenetic
analysis suggests that theFT group and theTFL1/CEN group of genes diverged before the diversification of major angiosperm clades. This raises the interesting question of the
evolutionary relationship between the regulation of vegetative/reproductive switching in the shoot apical meristem and the
regulation of inflorescence architecture in angiosperms.
The extended abstract of a paper presented at the 13th International Symposium in Conjugation with Award of the International
Prize for Biology “Fronitier of Plant Biology” 相似文献
195.
Kanako Hisata S. Fujiwara Yuko Tsuchida M. Ohashi Kazuo Kawamura 《Development genes and evolution》1998,208(10):537-546
Retinoic acid is thought to induce transdifferentiation of multipotent epithelial stem cells in the developing buds of the
ascidian Polyandrocarpa misakiensis. We isolated a cDNA clone from this species, named PmRAR, encoding a retinoic acid receptor (RAR) homologue. PmRAR clusters
with other RARs on phylogenetic trees constructed by three different methods. Within the cluster, PmRAR is on a separate branch
from all the subtypes of RARs, suggesting that RAR subtypes arose in the ancestral vertebrates after divergence of vertebrates
and urochordates. The embryos of another ascidian species Ciona intestinalis were co-electroporated with a mixture of a PmRAR expression vector and a lacZ reporter plasmid containing vertebrate-type retinoic acid response elements. The expression of lacZ depended on the presence of both retinoic acid and PmRAR, suggesting that PmRAR is a functional receptor. PmRAR mRNA is expressed
in the epidermis and mesenchyme cells of the Polyandrocarpa developing bud. The mRNA is not detectable in the mesenchyme cells in the adult body wall, but its expression can be induced
by retinoic acid in vitro. These results suggest that the PmRAR is a mediator of retinoic acid signalling in transdifferentiation
during asexual reproduction of protochordates.
Received: 6 April 1998 / Accepted: 27 July 1998 相似文献
196.
cDNA cloning, gene expression and subcellular localization of anthocyanin 5-aromatic acyltransferase from
Gentiana triflora 总被引:5,自引:3,他引:2
Hiroyuki Fujiwara Yoshikazu Tanaka Keiko Yonekura-Sakakibara Masako Fukuchi-Mizutani Masahiro Nakao Yuko Fukui Masaatsu Yamaguchi Toshihiko Ashikari Takaaki Kusumi 《The Plant journal : for cell and molecular biology》1998,16(4):421-431
Acylation of anthocyanins with hydroxycinnamic acid derivatives is one of the most important and less understood modification reactions during anthocyanin biosynthesis. Anthocyanin aromatic acyltransferase catalyses the transfer of hydroxycinnamic acid moieties from their CoA esters to the glycosyl groups of anthocyanins. A full-length cDNA encoding the anthocyanin 5-aromatic acyltransferase (5AT) ( EC 2.3.1.153 ) that acylates the glucose bound at the 5-position of anthocyanidin 3,5-diglucoside was isolated from petals of Gentiana triflora on the basis of the amino acid sequence of the purified enzyme. The isolated full-length cDNA had an open reading frame of 469 amino acids and the calculated molecular weight was 52 736. The deduced amino acid sequence contains consensus motifs that are conserved among the putative acyl CoA-mediated acyltransferases, and this indicates that 5AT is a member of a proposed superfamily of multifunctional acyltransferases ( St-Pierre et al . (1998 ) Plant J. 14, 703–713). The cDNA was expressed in Escherichia coli and yeast, and confirmed to encode 5AT. The enzymatic characteristics of the recombinant 5AT were consistent with those of the native gentian 5AT. Immunoblot analysis using specific antibodies to 5AT showed that the 5AT protein is present in petals, but not in sepals, stems or leaves of G. triflora . RNA blot analysis showed that the 5AT gene is expressed only in petals and that its expression is temporally regulated during flower development coordinately with other anthocyanin biosynthetic genes. Immunohistochemical analysis demonstrated that the 5AT protein is specifically expressed in the outer epidermal cells of gentian petals and that it is localized mainly in the cytosol. 相似文献
197.
Yumi Moriwake Yoshiyuki Tohno Setsuko Tohno Takeshi Minami Masako Utsumi Fumio Nishiwaki Masa-oki Yamada Hiroshi Yamamoto Yuko Okazaki Tadashi Fujii Yoshinori Takakura 《Biological trace element research》1998,64(1-3):229-235
The relative contents (RCs) of elements in the human menisci from 23 subjects in the age range between 65 and 93 yr were analyzed
by inductively coupled plasma atomic emission spectrometry. The RCs of sulfur, calcium, and phosphorus in menisci increased
progressively until the 80s, being the highest in the 80s, and thereafter decreased. The RCs of magnesium in menisci increased
progressively until the 90s. Regarding the medial and lateral menisci, higher RCs of magnesium and iron, and a lower RC of
phosphorus were found in lateral menisci in comparison with those in medial menisci.
There were sexual differences in the RCs of calcium and phosphorus of medial and lateral menisci. The RCs of calcium and phosphorus
were about 50% higher in women’s menisci than in men’s. Histological examinations showed that structureless mucoid masses
were observed in the menisci, with very high RCs of calcium and phosphorus being detected. 相似文献
198.
199.
Satoi Nagasawa Anna S. Sedukhina Yuko Nakagawa Ichiro Maeda Manabu Kubota Shigeko Ohnuma Koichiro Tsugawa Tomohiko Ohta Marta Roche-Molina Juan A. Bernal Ana J. Narváez Anand D. Jeyasekharan Ko Sato 《PloS one》2015,10(2)
LSD1, a lysine-specific histone demethylase, is overexpressed in several types of cancers and linked to poor outcomes. In breast cancer, the significance of LSD1 overexpression is not clear. We have performed an in silico analysis to assess the relationship of LSD1 expression to clinical outcome. We demonstrate that LSD1 overexpression is a poor prognostic factor in breast cancer, especially in basal-like breast cancer, a subtype of breast cancer with aggressive clinical features. This link is also observed in samples of triple negative breast cancer. Interestingly, we note that overexpression of LSD1 correlates with down-regulation of BRCA1 in triple negative breast cancer. This phenomenon is also observed in in vitro models of basal-like breast cancer, and is associated with an increased sensitivity to PARP inhibitors. We propose therefore that high expression levels of the demethylase LSD1 is a potential prognostic factor of poor outcome in basal-like breast cancer, and that PARP inhibition may be a therapeutic strategy of interest in this poor prognostic subtype with overexpression of LSD1. 相似文献
200.
Mari Narusaka Taichi Minami Chikako Iwabuchi Takashi Hamasaki Satoko Takasaki Kimito Kawamura Yoshihiro Narusaka 《PloS one》2015,10(1)
Housaku Monogatari (HM) is a plant activator prepared from a yeast cell wall extract. We examined the efficacy of HM application and observed that HM treatment increased the resistance of Arabidopsis thaliana and Brassica rapa leaves to bacterial and fungal infections. HM reduced the severity of bacterial leaf spot and anthracnose on A. thaliana and Brassica crop leaves with protective effects. In addition, gene expression analysis of A. thaliana plants after treatment with HM indicated increased expression of several plant defense-related genes. HM treatment appears to induce early activation of jasmonate/ethylene and late activation of salicylic acid (SA) pathways. Analysis using signaling mutants revealed that HM required SA accumulation and SA signaling to facilitate resistance to the bacterial pathogen Pseudomonas syringae pv. maculicola and the fungal pathogen Colletotrichum higginsianum. In addition, HM-induced resistance conferred chitin-independent disease resistance to bacterial pathogens in A. thaliana. These results suggest that HM contains multiple microbe-associated molecular patterns that activate defense responses in plants. These findings suggest that the application of HM is a useful tool that may facilitate new disease control methods. 相似文献