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2.
The biological roots of morality 总被引:2,自引:0,他引:2
Francisco J. Ayala 《Biology & philosophy》1987,2(3):235-252
The question whether ethical behavior is biologically determined may refer either to thecapacity for ethics (e.i., the proclivity to judge human actions as either right or wrong), or to the moralnorms accepted by human beings for guiding their actions. My theses are: (1) that the capacity for ethics is a necessary attribute of human nature; and (2) that moral norms are products of cultural evolution, not of biological evolution.Humans exhibits ethical behavior by nature because their biological makeup determines the presence of the three necessary, and jointly sufficient, conditions for ethical behavior: (i) the ability to anticipate the consequences of one's own actions; (ii) the ability to make value judgements; and (iii) the ability to choose between alternative courses of action. Ethical behavior came about in evolution not because it is adaptive in itself, but as a necessary consequece of man's eminent intellectual abilities, which are an attribute directly promoted by natural selection.Since Darwin's time there have been evolutionists proposing that the norms of morality are derived from biological evolution. Sociobiologists represent the most recent and most subtle version of that proposal. The sociobiologists' argument is that human ethical norms are sociocultural correlates of behaviors fostered by biological evolution. I argue that such proposals are misguided and do not escape the naturalistic fallacy. The isomorphism between the behaviors promoted by natural selection and those sanctioned by moral norms exist only with respect to the consequences of the behaviors; the underlying causations are completely disparate.This article is based on a paper presented at the International Symposium onBiological Models of Human Action, Palma de Mallorca, Spain, 16–18 December 1985. 相似文献
3.
E Escamilla G Ayala M T de Gómez-Puyou A Gómez-Puyou L Millán A Darszon 《Archives of biochemistry and biophysics》1989,272(2):332-343
Cytochrome c and cytochrome oxidase, in bovine heart submitochondrial particles and in their purified forms, were transferred to a ternary system that contained phospholipids (10 mg/ml toluene), the apolar solvent toluene, and water at concentrations of 13-15 microliters (high water) and 3 microliters (low water) per milliliter of toluene. When the enzymes were transferred back to an all water system, they exhibited full catalytic capacity. In the low water ternary system, cytochrome c could be reduced by ascorbate introduced via inverted micelles. Also in this system, cytochrome oxidase was reduced by ascorbate and cytochrome c but its oxidation was highly impaired. Data on the kinetics of reduction by ascorbate of cytochrome c and cytochrome oxidase under these conditions are presented. Cytochrome oxidase reduced in the organic solvent by ascorbate failed to form a complex with CO, but formed a complex with cyanide introduced via inverted micelles. The oxidized and the ascorbate-reduced cytochrome oxidase-cyanide complex exhibited a trough at 415 nm and a peak at 433 nm. The extent and rate of formation of the cyanide complex were higher with the reduced form of cytochrome oxidase. To achieve protein-protein interactions (cytochrome c-cytochrome oxidase) in the ternary system, it was necessary to extract the two proteins together. There was no functional interaction when they were extracted separately and mixed. In the high water ternary system reduced cytochrome oxidase was not detected, and it oxidized ascorbate at a higher rate than in the low water system; however, this rate was several orders of magnitude lower than in aqueous media. 相似文献
4.
A lacZ-pbpB gene fusion coding for an inducible hybrid protein that recognizes localized sites in the inner membrane of Escherichia coli. 总被引:4,自引:4,他引:0 下载免费PDF全文
An in-phase gene fusion consisting of the 5'-terminal 1,314 base pairs (bp) of the structural gene for beta-galactosidase (lacZ) and the 3'-terminal 1,644 bp of the structural gene coding for penicillin-binding protein 3 (pbpB) of Escherichia coli was constructed and cloned in the plasmid pDIAM64. The product of the fusion gene was a remarkably stable protein with an apparent molecular weight of 110,000 (p110) that retained the ability to covalently interact with beta-lactam antibiotics. The fusion protein was found associated with the membrane at low levels of induction, but it accumulated in the cytoplasm of cells induced for a long time as inclusion bodies of high density. Inclusion bodies were localized at defined positions corresponding to septal sites in all of the pDIAM64-containing strains tested except PAT84 and GD113 (which carry the ftsZ84 mutant allele). These findings indicate a possible role of the FtsZ protein in the integration of Pbp3 into the membrane and in septum localization during the cell division cycle. 相似文献
5.
Production of pili on Vibrio parahaemolyticus 总被引:4,自引:0,他引:4
Electron microscopic examination showed that all strains of Vibrio parahaemolyticus examined had pili on their surface when the organism was grown on marine agar at 28 degrees C for 6-12 h. The pili were morphologically stable on heat treatment at 60 degrees C for 10 min, but both the lateral and polar flagella possessed by this organism were labile. No immunological cross-reactivity between pili of enterotoxigenic Escherichia coli and Vibrio cholerae non-01 and those of V. parahaemolyticus was observed. 相似文献
6.
Two multisubunit enzymes of the inner mitochondrial membrane, cytochrome oxidase and the H+-ATPase may be transferred into highly apolar solvents as protein-lipid complexes. At 70 degrees C and an initial water concentration of 13 microliters per ml organic solvent (toluene), the half-life of the ATPase was approx. 11 h, whereas that of cytochrome oxidase was about 100 s. Thermostability of cytochrome oxidase could be increased more than 100-times by decreasing the water concentration to 3 microliters per ml toluene. At this latter concentration of water the half-life of the ATPase at 90, 80 and 70 degrees C was 5, 48 and 96 h, respectively. 相似文献
7.
On the virtues and pitfalls of the molecular evolutionary clock 总被引:6,自引:0,他引:6
F J Ayala 《The Journal of heredity》1986,77(4):226-235
"Informational" macromolecules--i.e., proteins and nucleic acids--have in their sequences a register of evolutionary history. Zuckerkandl and Pauling suggested in 1965 that these molecules might provide a "molecular clock" of evolution. The molecular clock would time evolutionary events and make it possible to reconstruct phylogenetic history--the branching relationships among lineages leading to modern species. Kimura's neutrality theory postulates that rates of molecular evolution are stochastically constant and, hence, that there is a molecular clock. A variety of tests have shown that molecular evolution does not behave like a stochastic clock. The variance in evolutionary rates is much too large and thus inconsistent with the neutrality theory. This, however, does not invalidate the clock, but rather leaves it without a theoretical foundation to anticipate its properties. Sequence comparisons show that molecular evolution is sufficiently regular to serve in many situations as a clock, but uncertainty concerning the properties of the clock (for example, about the circumstances that may yield large oscillations in substitution rates from time to time or from lineage to lineage) demands that it be used with caution. Few DNA or protein sequences are known from organisms that range from closely related, e.g., different mammals, to very remote, e.g., mammals and fungi. One example is cytochrome c, which has an acceptable clockwise behavior over the whole span, in spite of some irregularities. Another example is the copper-zinc superoxide dismutase (SOD), which behaves like a very erratic clock. The SOD average rate of amino acid substitution per 100 residues per 100 million years (MY) is 5.5 when fungi and animals are compared, 9.1 when comparisons are made between insects and mammals, and 27.8 when mammals are compared with each other. The question is which mode is more common over broad evolutionary spans: the regularity of cytochrome c or the capriciousness of SOD? Additional data sets will be required in order to obtain the answer and to develop expectations about the accuracy of the clock in particular instances. Until such data exist, conclusions solely based on the molecular clock are potentially fraught with error. 相似文献
8.
Natural Selection VS. Random Drift: Evidence from Temporal Variation in Allele Frequencies in Nature 总被引:1,自引:1,他引:0 下载免费PDF全文
We have obtained monthly samples of two species, Drosophila pseudoobscura and Drosophila persimilis, in a natural population from Napa County, California. In each species, about 300 genes have been assayed by electrophoresis for each of seven enzyme loci in each monthly sample from March 1972 to June 1975. Using statistical methods developed for the purpose, we have examined whether the allele frequencies at different loci vary in a correlated fashion. The methods used do not detect natural selection when it is deterministic (e.g., overdominance or directional selection), but only when alleles at different loci vary simultaneously in response to the same environmental variations. Moreover, only relatively large fitness differences (of the order of 15%) are detectable. We have found strong evidence of correlated allele frequency variation in 13-20% of the cases examined. We interpret this as evidence that natural selection plays a major role in the evolution of protein polymorphisms in nature. 相似文献
9.
Nitrate reductase: an improved assay method for phytoplankton 总被引:1,自引:0,他引:1
Hochman Ayala; Nissany Aliza; Wynne David; Kaplan Bina; Berman Thomas 《Journal of plankton research》1986,8(2):385-392
A new assay for measuring the activity of nitrate reductasein phytoplankton, based upon the permeability of cells treatedwith toluene to substrates and products, is described. The methodis simple and, since the reaction is carried out directly ona glass fiber filter, can be easily performed in the field oron shipboard. In comparison with previous methods, this techniquegave higher absolute amounts of NO2 formed per unit tuneand higher enzymatic activities per sample volume when testedwith axenic algal cultures and with natural phytoplankton populationsfrom Lake Kinneret, the River Jordan and the Eastern Mediterranean. 相似文献
10.
The results of 11 experiments with Drosophila species show that fertility is not a reducible property: the fertility of a mating pair cannot be predicted from the average fertility of the two genotypes involved. We propose a model of fertility selection that does not assume additivity (or multiplicativity) but assumes random mating and that the genotypic frequencies are in Hardy-Weinberg equilibrium. Numerical simulations show that removal of the assumption of Hardy-Weinberg frequencies does not significantly change the equilibrium frequencies predicted by the model. 相似文献