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41.
42.
We cloned and sequenced cDNAs encoding calponin (Calp) and SM22 (smooth muscle-specific 22-kDa protein) from rat aorta (RaA) smooth muscle (Smu) cells. The 1504-bp calp cDNA contains a single open reading frame (ORF) which encodes 297 amino acids (aa) (Mr 33 342). The 1186-bp SM22 cDNA contains a single ORF which encodes 201 aa (Mr 22 601). There were 43% identical aa in a 181-aa overlap between RaA Calp and SM22. Especially for the C-terminal region of SM22 and for the first repeat motif of Calp, 70% identity was observed. Northern blot analysis revealed that the calp and SM22 mRNAs were expressed in RaA Smu, but not in rat cardiac and skeletal muscles. SM22 mRNA was much more abundant than calp mRNA in RaA (3- to 4-fold). The expression levels of the calp and SM22 mRNAs in RaA showed a significant increase for 5 to 15 week old rats (1.5- to 3-fold) with vascular development and blood pressure elevation. No significant differences were observed in the expression of the RaA calp and SM22 mRNAs between normotensive (Wistar Kyoto) and spontaneously hypertensive rats (SHR). 相似文献
43.
44.
Successful expression in pollen of various plant species of in vitro synthesized mRNA introduced by particle bombardment 总被引:5,自引:0,他引:5
Toshinori Tanaka Masahiro Nishihara Motoaki Seki Atsushi Sakamoto Kunisuke Tanaka Kohei Irifune Hiromichi Morikawa 《Plant molecular biology》1995,28(2):337-341
Gold particles coated with -glucuronidase (GUS) mRNA with a 5 cap structure that had been synthesized in vitro were introduced, by use of a pneumatic particle gun, into pollen grains of lily (Lilium longiflorum), freesia (Freesia refracta) and tulip (Tulipa gesneriana). A fluorometric assay for the GUS activity indicated that in vitro synthesized GUS mRNA introduced into these pollen cells by particle bombardment was successfully expressed. GUS activity in extracts of the bombarded lily pollen became detectable fluorometrically within 30 min after bombardment, peaked at 6 h, then gradually decreased. This activity changed as a function of the developmental stage of the pollen cell of lily. 相似文献
45.
Variations in mitochondrial tRNA gene organization of reptiles as phylogenetic markers 总被引:11,自引:2,他引:9
Amplification and sequencing of mitochondrial DNA regions corresponding to
three major clusters of transfer RNA genes from a variety of species
representing major groups of birds and reptiles revealed some new
variations in tRNA gene organization. First, a gene rearrangement from
tRNA(His)-tRNA(Ser)(AGY)-tRNA(Leu)(CUN) to tRNA(Ser)(AGY)-
tRNA(His)tRNA(Leu)(CUN) occurs in all three crocodilians examined
(alligator, caiman, and crocodile). In addition an exceptionally long
spacer region between the genes for NADH dehydrogenase subunit 4 and
tRNA(Ser)(AGY) is found in caiman. Second, in congruence with a recent
finding by Seutin et al., a characteristic stem-and-loop structure for the
putative light-strand replication origin located between tRNA(Asn) and
tRNA(Cys) genes is absent for all the birds and crocodilians. This
stem-and-loop structure is absent in an additional species, the Texas blind
snake, whereas the stem-and-loop structure is present in other snakes,
lizards, turtles, mammals, and a frog. The disappearance of the
stem-and-loop structure in the blind snake most likely occurred
independently of that on the lineage leading to birds and crocodilians.
Finally, the blind snake has a novel type of tRNA gene arrangement in which
the tRNA(Gln) gene moved from one tRNA cluster to another. Sequence
substitution rates for the tRNA genes appeared to be somewhat higher in
crocodialians than in birds and mammals. As regards the controversial
phylogenetic relationship among the Aves, Crocodilia, and Mammalia, a
sister group relationship of birds and crocodilians relative to mammals, as
suggested from the common loss of the stem-and- loop structure, was
supported with statistical significance by molecular phylogenetic analyses
using the tRNA gene sequence data.
相似文献
46.
This paper describes six species of permineralized pinoid woods with resin canals from the Upper Cretaceous of Hokkaido, Japan
and Saghalien:Piceoxylon transiens Shimakura,P. scleromedullosum Shimakura,P. macroporosum sp. nov.,P. takahashii sp. nov.,Pinuxylon microporosum Ogura andPinoxylon dakotense (Knowlton) Read (new to Saghalien and the Cretaceous).Piceoxylon macroporosum is characterized by large resin canals and rays without ray tracheids and in lacking tylosoids in resin canals.Piceoxylon takahashii, which resemblesP. scleromedullosum, is distinguished from the latter in having ray tracheids and nests of sclereids in pith.
Structure and affinities of the petrified plants from the Cretaceous of Northern Japan and Saghalien XVI. (continued from
Ohsawaet al. 1995) 相似文献
47.
A new specimen of an araucarian cone,Araucaria nihongii, was found attached to the vegetative organs ofYezonia vulgaris, and is described asAraucaria vulgaris comb. nov. Thick branches show characteristic bark structure with lenticular patches. Secondary wood is usually araucarioid.
Leaves are arranged helically on shoots, which are imbricate, appressed and fused to surface of the stem. External and anatomical
features of leaves closely resembleBrachyphyllum. The seed cone is spherical with winged bracts and thin ovuliferous scales. One seed is borne per cone-scale complex. The
seed coat and nucellus wall show typical araucarian structure. An araucarian plant that boreBrachyphyllum-like foliage and aEutacta-like seed cone was predicted by Harris in 1979. This reconstructed plant,Araucaria vulgaris, supports this theory and proves the presence of an extinct characteristic-form of the genus. A new section of the genus
was proposed forAraucaria vulgaris.
Structure and Affinities of the Petrified Plants from the Cretaceous of Northern Japan and Saghalien XV, Consecutive number
from previous paper (Nishidaet al. 1993). 相似文献
48.
49.
Flowering responses to a single photoperiod, of various durationsand irradiances, followed by an inductive dark period were investigatedwith dark-grown seedlings of Pharbitis nil Choisy. The numberof flower buds induced in each plant (NFB) increased with theincrease of both duration and irradiance of the photoperiod.Reciprocity did not hold for this photoresponse within the rangeof 0-16 h and 2.5-10 W-m-2, NFB depending on the duration ratherthan the irradiance. With lengthening of the dark period followinga photoperiod of 8 h or less, two different phases alternatelyappeared so that NFB sharply increased at 20-24 h and 40-43h after the onset of the photoperiod, then gradually decreased.When the photoperiod was longer than 8 h, NFB sharply increasedat 1216 h after the end of the photoperiod and remainedaround the saturated value with longer dark periods. Far-redlight given immediately after the photoperiod inhibited flowering,the inhibitory effect being stronger the shorter the photoperiod.This far-red effect is mediated by phytochrome and PFR seemsto be required during the inductive dark period following ashort photoperiod for floral induction. (Received December 23, 1983; Accepted April 12, 1984) 相似文献
50.