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71.
D. K. X. Chong C. C. Chinnappa F. C. Yeh S. Chuong 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,88(5):614-617
Inheritance of chloroplast DNA (cpDNA) was examined in F1 progenies derived from three crosses and three corresponding reciprocal crosses betweenStellaria porsildii andS. longifolia. Chloroplast DNA restriction fragments were analyzed using methods of nonradioactive digoxigenin-11-dUTP labeling and chemiluminescent detection with Lumi-Phos 530. Distinct interspecific restriction fragment polymorphisms were identified and used to demonstrate the mode of cpDNA inheritance. Mode of cpDNA inheritance differed among crosses. Two crosses in whichS. porsildii, SP2920-21, was the maternal parent exhibited three different types of plastids, maternal, paternal and biparental, among the F1 hybrids, suggesting a biparental cpDNA inheritance and plastid sorting-out inStellaria. 相似文献
72.
Gerard Berger Guy Girault Jean-Michel Galmiche Stephane Pezennec 《Journal of bioenergetics and biomembranes》1994,26(3):335-346
The influences of total magnesium ion concentration at different total ATP concentrations, and of total ATP concentration, for different total magnesium ion concentrations, on the enzymatic rate of the isolated chloroplast F1 ATPase, have been followed by a chromatographic method consisting in the separation and determination of ADP. From the various series of curves, it is concluded that the experimental results (position of the maxima,K
m
values) are better fitted by a mechanism involving the activation of the enzyme by magnesium ion and hydrolysis of free ATP, rather than by the classical mechanism, for which the enzyme hydrolyzes the MgATP complex and is inhibited by Mg2+. Although the equations giving the reaction rate are similar in the two cases, the calculated values ofK
m
are widely different. The value obtained from the classical mechanism does not agree withK
D
, the dissociation constant of the enzyme-substrate complex, measured by the Hummel and Dreyer method. Moreover, when the total ATP concentration tends toward the total magnesium ion concentration, the nucleotide binding to the enzyme tends toward zero, although it should be maximum if MgATP were the true substrate. Finally, the inhibitory effect of Na+ is more easily explained as a competition between this ion and the activating Mg2+, than by the classical mechanism. 相似文献
73.
74.
Genetic variation of microsatellite loci in a bottlenecked species: the northern hairy-nosed wombat Lasiorhinus krefftii 总被引:12,自引:0,他引:12
We investigate the utility of hypervariable microsatellite loci to measure genetic variability remaining in the northern hairy-nosed wombat, one of Australia's rarest mammals. This species suffered a dramatic range and population reduction over the past 120 years and now exists as a single colony of about 70 individuals at Epping Forest National Park, central Queensland. Because our preliminary research on mitochondrial DNA and multilocus DNA fingerprints did not reveal informative variation in this population, we chose to examine variation in microsatellite repeats, a class of loci known to be highly polymorphic in mammals. To assess the suitability of various wombat populations as a reference for comparisons of genetic variability and subdivision we further analysed mitochondrial DNA cytochrome b sequence, using phylogenetic methods. Our results show that appreciable levels of variation still exist in the Epping Forest colony although it has only 41% of the heterozygosity shown in a population of a closely-related species. From museum specimens collected in 1884, we also assessed microsatellite variation in an extinct population of the northern hairy-nosed wombat, from Deniliquin, New South Wales, 2000 km to the south of the extant population. The apparent loss of variation in the Epping Forest colony is consistent with an extremely small effective population size throughout its 120-year decline. 相似文献
75.
Birgitta Bremer Richard G. Olmstead Lena Struwe Jennifer A. Sweere 《Plant Systematics and Evolution》1994,190(3-4):213-230
The taxonomic positions ofRetzia, Desfontainia, andNicodemia have been much discussed, and all three genera have been included inLoganiaceae (Gentianales). We have made a cladistic analysis ofrbcL gene sequences to determine the relationships of these taxa toGentianales. Four newrbcL sequences are presented; i.e., ofRetzia, Desfontainia, Diervilla (Caprifoliaceae), andEuthystachys (Stilbaceae). Our results show thatRetzia, Desfontainia, andNicodemia are not closely related toLoganiaceae or theGentianales. Retzia is most closely related toEuthystachys and is better included inStilbaceae. The positions ofDesfontainia andNicodemia are not settled, butDesfontainia shows affinity for theDipsacales s.l. andNicodemia for theLamiales s.l. 相似文献
76.
Chloroplast DNA restriction site variation was examined for 35 taxa in theVernonieae and four outgroup tribes, using 17 restriction enzymes mapped for ca. 900 restriction sites per species; 139 mutations were found to be phylogenetically informative. Phylogenetic trees were constructed using Wagner and weighted parsimony, and evaluated by bootstrap and decay analyses. Relationships of Old and New World taxa indicate complex geographical relationships; there was no clear geographic separation by hemisphere. The relationships between Old and New World Vernonias found here support prior morphological analyses. The sister group to all New and most Old World taxa was composed of a small group of Old World species including yellow-flowered, trinervate-leaved species previously postulated to be basal in the tribe. The majority of both New and Old World taxa are derived from a lineage beginning with the monotypic genusStokesia, an endemic of the southeastern United States. The genusVernonia was also found to be paraphyletic within both the New and Old World. Available data do not support either the separation ofVernonia or the tribeVernonieae into geographically distinct lineages. The pattern of relationships within theVernonieae for taxa from North America, Asia, Africa, Central and South America is most similar to that of several other groups of both plants and animals with a boreotropical origin, rather than an origin in Gondwanaland. Such a pattern of distribution suggests more ancient vicariant events than are routinely postulated for theAsteraceae. 相似文献
77.
Friedrich Ehrendorfer Jean-François Manen Alessandro Natali 《Plant Systematics and Evolution》1994,190(3-4):245-248
Representatives of seven genera from five tribes ofRubiaceae have been compared in respect to a non-coding intergene cpDNA region of about 1000 bp, situated between the atpB and the rbcL genes. The resulting most parsimonious PAUP cladogram corresponds very well with one based on total cpDNA restriction site data obtained byBremer & Jansen (1991). The two different molecular analyses thus corroborate each other and contribute to an improved systematic arrangement of the large family, e.g., in respect to placing the tribeHedyotideae clearly into the subfamilyRubioideae, closer toRubieae than toPsychotrieae. 相似文献
78.
Molecular phylogeny in the Lardizabalaceae 总被引:1,自引:0,他引:1
Rumiko Kofuji Kunihiko Ueda Kazuo Yamaguchi Tatemi Shimizu 《Journal of plant research》1994,107(3):339-348
Eleven species belonging to seven genera in the Lardizabalaceae were analyzed in terms of restriction fragment length polymorphism
(RFLP) of chloroplast DNA and the sequence of the chloroplast gene,rbcL, of Lardizabalaceae and its related families. Phylogenetic trees inferred from parsimony, neighbor joining and maximum likelihood
methods based on RFLP data showed that two South American genera,Boquila andLardizabala, and three East Asian genera,Akebia, Holboellia andStauntonia are closely related to each other, respectively. On the other hand, the parsimony, neighbor joining and maximum likelihood
trees constructed using sequence data of therbcL gene showed thatAkebia, Stauntonia, Boquila andLardizabala clustered as(((Akebia, Stauntonia), Boquila), Lardizabala). This difference may be attributable to fewer informative sites inrbcL genes than in RFLP in this family.Decaisnea diverges at the very base of the Lardizabalaceae. 相似文献
79.
Chloroplast DNA (cpDNA) restriction site variation was examined in five species ofDesmodium subgenusPodocarpium (Leguminosae; Papilionoideae; Desmodieae). Twenty four phylogenetically informative cpDNA mutations were scored. The cladistic
analysis of characters based on the 24 mutations resulted in the most parsimonious tree which supports the monophyly of the
subgenus.Desmodium elegans of subgenusDollinera was the sister group of subgenusPodocarpium in this tree. The groupings obtained from the cpDNA characters were consistent with the present infrageneric classification
system for the subgenus except for the infraspecific taxa ofD. podocarpum. Three groups withinD. podocarpum, which were incongruent with the infraspecific classification of the species, were distinguished by a total of four site
mutations. The first group consisted of subsp.podocarpum, subsp.fallax, and subsp.oxyphyllum var.oxyphyllum; the second subsp.oxyphyllum var.oxyphyllum; and the last subsp.oxyphyllum var.oxyphyllum and var.mandshuricum. 相似文献
80.
S. Hentrich M. Hebeler L. H. Grimme D. Leibfritz A. Mayer 《European biophysics journal : EBJ》1993,22(1):31-39
ATP synthesis and consumption in respiring cells of the green alga Chlamydomonas reinhardtii were measured with 31P in vivo NMR saturation transfer experiments to determine the intracellular compartmentation of inorganic phosphate. Most of the observed flux towards ATP synthesis was catalyzed by the coupled enzymes glyceraldehyde-3-phosphate dehydrogenase/phosphoglycerate kinase (GAPDH/PGK). The attribution of the measured flux to these enzymes is supported by the observation, that (i) the magnetization transfer was strongly reduced by iodoacetate, an irreversible inhibitor of GAPDH and that (ii) the unidirectional flux was much greater than the net flux through the mitochondrial F0F1-ATPase as determined by oxygen consumption measurements. In Chlamydomonas, glycolysis is divided into a chloroplastidic and a cytosolic part with the enzymes GAPDH/PGK being located in the chloroplast stroma (Klein 1986). The 31P-NMR signal of inorganic phosphate must, therefore, originate from the chloroplast. The life time of the magnetic label transferred to Pi by these enzymes is too short for it to be transported to the cytosol via the phosphate translocator of the chloroplast envelope. When the intracellular compartmentation of Pi was taken into consideration the calculated unidirectional ATP synthesis rate was equal to the consumption rate, indicating operation of GAPDH/PGK near equilibrium. The assignment of most of the intracellular Pi to the chloroplast is in contradiction to earlier reports, which attributed the Pi signal to the cytosol. This is of special interest for the use of the chemical shift of the Pi signal as an intracellular pH-marker in plant cells.Abbreviations 3-PGA
3-phosphoglycerate
- CW
continuous wave
- dG6P
2-deoxyglucose-6-phosphate
- GAPDH
glyceraldehyde-3-phosphate dehydrogenase
- MO
equilibrium z-magnetization
- M0
instantaneous z-magnetization after selective saturation for time t
- MDP
methylene-diphosphonic acid
- PDE
phosphodiester
- PGK
phosphoglycerate kinase
- Pi
inorganic orthophosphate
- polyP
polyphosphate
- T1
longitudinal relaxation time
- 1
longitudinal relaxation time with chemical exchange
- TCA cycle
tricarboxylic acid cycle
Correspondence to: A. Mayer 相似文献