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161.
162.
Avise JC; Shapira JF; Daniel SW; Aquadro CF; Lansman RA 《Molecular biology and evolution》1983,1(1):38-56
We address the problem of the possible significance of biological
speciation to the magnitude and pattern of divergence of asexually
transmitted characters in bisexual species. The empirical data for this
report consist of restriction endonuclease site variability in maternally
transmitted mitochondrial DNA (mtDNA) isolated from 82 samples of
Peromyscus polionotus and P. leucopus collected from major portions of the
respective species' ranges. Data are analyzed together with previously
published information on P. maniculatus, a sibling species to polionotus.
Maps of restriction sites indicate that all of the variation observed can
be reasonably attributed to base substitutions leading to loss or gain of
particular recognition sites. Magnitude of mtDNA sequence divergence within
polionotus (maximum approximately equal to 2%) is roughly comparable to
that observed within any of five previously identified mtDNA assemblages in
maniculatus. Sequence divergence within leucopus (maximum approximately
equal to 4%) is somewhat greater than that within polionotus. Consideration
of probable evolutionary links among mtDNA restriction site maps allowed
estimation of matriarchal phylogenies within polionotus and leucopus.
Clustering algorithms and qualitative Wagner procedures were used to
generate phenograms and parsimony networks, respectively, for the
between-species comparisons. Three simple graphical models are presented to
illustrate some conceivable relationships of mtDNA differentiation to
speciation. In theoretical case I, each of two reproductively defined
species (A and B) is monophyletic in matriarchal genealogy; the common
female ancestor of either species can either predate or postdate the
speciation. In case II, neither species is monophyletic in matriarchal
genotype. In case III, species B is monophyletic but forms a subclade
within A which is thus paraphyletic with respect to B. The empirical
results for mtDNA in maniculatus and polionotus appear to conform closely
to case III. These theoretical and empirical considerations raise a number
of questions about the general relationship of the speciation process to
the evolution of uniparentally transmitted traits. Some of these
considerations are presented, and it is suggested that the distribution
patterns of mtDNA sequence variation within and among extant species should
be of considerable relevance to the particular demographies of speciation.
相似文献
163.
Lise Samsøe-Petersen 《BioControl》1987,32(1):73-81
Tests were conducted in glass cells containing moistened sand sprayed with the concentration recommended for the pesticide
or with demineralised water (controls). Adult females (1–2 weeks old) ofA. bilineata were placed on the fresh residue in the cells and provided daily with fresh fly eggs as food. The duration of the test was
5 days, mortality being recorded every day. The side effects of the pesticide were expressed as reduction in egg production
ofA. bilineata during the whole test period. Results permitted classification of the pesticides according to the 4 categories of harmfulness
used by the IOBC working group. 23 pesticides were tested, and the reproducibility of the test appeared to be satisfactory.
Generally, insecticides/acaricides had a pronounced effect on the beetles whereas fungicides and herbicides were less detrimental.
Exceptions were the insecticides Tedion V 18 and Kilval, classified as harmless, and the fungicides Morestan, Pomarsol forte
and Afugan rated as moderately harmful. Among growth regulators Prosevor 85 was highly detrimental while Cycocel Extra and
Rhodofix had no effects. Excepting Morestan, Pomarsol forte and Ustinex PA the pesticides did not affect the hatching of eggs.
The work was financed by the Danish Environmental Protection Agency. 相似文献
164.
L. Samsøe-Petersen 《BioControl》1995,40(2):145-152
Effects of 37 fungicides — several of which were mixtures — on adult females of the rove beetle,Aleochara bilineata, were investigated in the laboratory. The pesticides were tested in concentrations equivalent to the highest recommended
dosages for practical use. Mortality, egg production and hatch of the eggs were recorded.
Most fungicides had no serious effect on any of the parameters measured. Among the morpholine and dithiocarbamate fungicides,
several had adverse effects on egg production and/or hatch of the eggs laid. Furthermore, chinomethionate and pyrazophos were
found to be toxic at the dosages used. Results are compared to results obtained with other species of beneficial arthropods
in the laboratory. The importance of including several species in the assessment of pesticide side effects as well as the
importance of measuring sublethal effects are stressed.
Résumé Des expériences de laboratoire ont été faites pour étudier les effets de 37 fongicides (dont plusieurs étaient des mélanges) sur les femelles adultes d'Aleochara bilineata. Les pesticides ont été testés à des concentrations équivalant aux plus fortes doses recommandées pour l'usage agricole. La mortalité, la production et l'éclosion des œufs ont été étudiées. La plupart des fongicides n'ont pas d'effet important sur aucun des paramètres retenus. Parmi les fongicides à base de morpholine et de dithiocarbamate, plusieurs avaient un effet contraire sur la production et l'éclosion des œufs. En outre le chinométhionate et le pyrazophos se sont révélés toxiques aux doses utilisées. Les résultats ont été comparés à d'autres résultats obtenus avec d'autres espèces d'auxiliaires au laboratoire. L'importance d'inclure plusieurs espèces dans l'évaluation des effects secondaires des pestieides ainsi que l'importance de mesurer les effets sublétaux sont soulignées.相似文献
165.
Debora Napoli Leonardo Lupori Raffaele Mazziotti Giulia Sagona Sara Bagnoli Muntaha Samad Erika K Sacramento Joanna Kirkpartick Elena Putignano Siwei Chen Eva Terzibasi Tozzini Paola Tognini Pierre Baldi Jessica CF Kwok Alessandro Cellerino Tommaso Pizzorusso 《EMBO reports》2021,22(1)
The authors regret having omitted grant attributions in the original publication. The funding section is herewith updated to reflect the change. “Funding attributed to Tommaso Pizzorusso was provided by EPIGEN Flagship project and PRIN2017HM8FA, funding attributed to Alessandro Cellerino was provided by Fondazione Pisa ETHERNA project, funding attributed to Pierre Baldi was provided by NIH (grant NIH ), funding attributed to Jessica Kwok was provided by the Leverhulme Trust project grant (RPG‐2018‐100).” GM123558相似文献
166.
167.
D. R. Panthee V. R. Pantalone A. M. Saxton D. R. West C. E. Sams 《Molecular breeding : new strategies in plant improvement》2006,17(1):79-89
Soybean [Glycine max (L.) Merr.] is the single largest source of protein in animal feed. However, few studies have been conducted to evaluate
genomic regions controlling amino acid composition in soybean. It is important to study the genetics of amino acid composition
to achieve improvements through breeding. The objectives of this study were to determine the ratios between essential to non-essential
(E:NE) and essential to total (E:T) amino acids, and to identify genomic regions controlling essential and non-essential amino
acid composition in soybean seed. To achieve these objectives, 101 F6-derived recombinant inbred lines (RIL) developed from a cross of N87-984-16 × TN93-99 were used. Ground soybean seed samples
were analyzed for amino acids using a near infrared spectroscopy (NIRS) instrument. A significant (p < 0.01) difference among the RIL was found for amino acid composition. Heritability estimates on an entry mean basis ranged
from 0.13 for His to 0.67 for Tyr. A total of 94 polymorphic simple sequence repeat (SSR) molecular genetic markers were screened
in DNA from progenies. Single factor ANOVA was used to identify candidate quantitative trait loci (QTL), which were then confirmed
by QTL Cartographer. At least one QTL for each amino acid was detected in this population. QTL linked to molecular markers
Satt143, Satt168, Satt203, Satt274 and Satt495 were associated with most of the amino acids. Phenotypic variation explained
by an individual QTL ranged from 9.4 to 45.3%. QTL detected for amino acids in soybean in this experiment are expected to
be useful for future breeding programs targeting development of improved soybean amino acid composition for human and animal
nutrition. 相似文献
168.
Andrew C. Benniston Glen M. Chapman Anthony Harriman Craig A. Sams 《Inorganica chimica acta》2006,359(3):753-758
A complete photophysical study has been carried out on an octahedral ruthenium(II) complex, incorporating two 4′-phenylethynyl-2,2′:6′,2″-terpyridine ligands. Weak emission is observed from the complex in fluid solution at room temperature, but both emission yield and lifetime increase as the temperature is lowered. Luminescence is confirmed to occur exclusively from the lowest energy triplet metal-to-ligand, charge-transfer (MLCT) state, though higher-lying MLCT and metal-centered states are required to adequately model the non-radiative decay kinetics. A comparison of parameters associated with deactivation of the complex and its counterpart, where only one terpy ligand incorporates the phenylethynyl unit, indicates that only the electron-vibrational coupling element is affected. It is also revealed that the extent of electron delocalisation at the triplet level does not critically depend on the number of 4-phenylethynyl-2,2′:6′,2″-terpyridine ligands in the complex. 相似文献
169.