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181.
Aslam MA Hulst M Hoving-Bolink RA de Wit AA Smits MA Woelders H 《Molecular ecology resources》2012,12(3):421-427
In birds, offspring sex ratio manipulation by mothers is now well established with potentially important consequences for evolution and animal breeding. In most studies on primary sex ratio of birds, eggs are sexed after incubation by the use of PCR methods targeted to the sex-linked CHD1 genes. Sexing of unincubated eggs would be preferred, but as fertile and infertile blastodiscs cannot be distinguished macroscopically, errors could arise from PCR amplifications of parental DNA associated with the vitelline membrane of infertile eggs. In this study, we stained blastodiscs without the vitelline membrane with Hoechst 33342. This allowed unequivocal distinction between fertile and infertile blastodiscs. Fertile blastodiscs contained thousands of fluorescent nuclei, whereas no nuclei were seen in infertile eggs. In addition, after nucleic acid analysis, fertile blastodiscs yielded much stronger chromosomal DNA and CHD1-targeted PCR bands on agarose gels compared with infertile blastodiscs. These findings indicate that fertile blastodiscs contain much more embryonic DNA than parental DNA, allowing reliable sexing of the fertile eggs. The differences between fertile and infertile blastodiscs in chromosomal DNA and CHD1 PCR banding intensities alone could also be used to distinguish fertile from infertile eggs without using Hoechst staining. We conclude that identifying fertile blastodiscs either by Hoechst staining or by analyzing the yield of chromosomal DNA and CHD1-PCR products, combined with CHD1-targeted PCR amplification, presents an easy and reliable method to sex unincubated eggs. 相似文献
182.
Ayme-Southgate AJ Southgate RJ Philipp RA Sotka EE Kramp C 《Journal of molecular evolution》2008,67(6):653-669
All striated muscles respond to stretch by a delayed increase in tension. This physiological response, known as stretch activation,
is, however, predominantly found in vertebrate cardiac muscle and insect asynchronous flight muscles. Stretch activation relies
on an elastic third filament system composed of giant proteins known as titin in vertebrates or kettin and projectin in insects.
The projectin insect protein functions jointly as a “scaffold and ruler” system during myofibril assembly and as an elastic
protein during stretch activation. An evolutionary analysis of the projectin molecule could potentially provide insight into
how distinct protein regions may have evolved in response to different evolutionary constraints. We mined candidate genes
in representative insect species from Hemiptera to Diptera, from published and novel genome sequence data, and carried out
a detailed molecular and phylogenetic analysis. The general domain organization of projectin is highly conserved, as are the
protein sequences of its two repeated regions—the immunoglobulin type C and fibronectin type III domains. The conservation
in structure and sequence is consistent with the proposed function of projectin as a scaffold and ruler. In contrast, the
amino acid sequences of the elastic PEVK domains are noticeably divergent, although their length and overall unusual amino
acid makeup are conserved. These patterns suggest that the PEVK region working as an unstructured domain can still maintain
its dynamic, and even its three-dimensional, properties, without the need for strict amino acid conservation. Phylogenetic
analysis of the projectin proteins also supports a reclassification of the Hymenoptera in relation to Diptera and Coleoptera.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
183.
Agnes Michalczyk Edward Bastow Mark Greenough James Camakaris David Freestone Philip Taylor Maria Linder Julian Mercer Margaret L Ackland 《The journal of histochemistry and cytochemistry》2008,56(4):389-399
A role for the copper transporter, ATP7B, in secretion of copper from the human breast into milk has previously not been reported, although it is known that the murine ortholog of ATP7B facilitates copper secretion in the mouse mammary gland. We show here that ATP7B is expressed in luminal epithelial cells in both the resting and lactating human breast, where it has a perinuclear localization in resting epithelial cells and a diffuse location in lactating tissue. ATP7B protein was present in a different subset of vesicles from those containing milk proteins and did not overlap with Menkes ATPase, ATP-7A, except in the perinuclear region of cells. In the cultured human mammary line, PMC42-LA, treatment with lactational hormones induced a redistribution of ATP7B from a perinuclear region to a region adjacent, but not coincident with, the apical plasma membrane. Trafficking of ATP7B was copper dependent, suggesting that the hormone-induced redistribution of ATP7A was mediated through an increase in intracellular copper. Radioactive copper ((64)Cu) studies using polarized PMC42-LA cells that overexpressed mAtp7B protein showed that this transporter facilitates copper efflux from the apical surface of the cells. In summary, our results are consistent with an important function of ATP7B in the secretion of copper from the human mammary gland. 相似文献
184.
185.
Mészáros Z Mészáros J Völgyi E Sziva A Pampakas P Prókai A Szmodis M 《Journal of physiological anthropology》2008,27(5):241-245
The prevalence of juvenile excess weight keeps growing in the more developed world (WHO, 1998). The aim of the study was to compare the prevalence of overweight and obesity in Hungarian schoolboys in 1980 and 2005.Two independent representative data collections were performed in volunteer boys aged between 6.51 and 18.50 years in the same 90 settlements of the country in 1980 (n=13,061) and 2005 (n=13,060). Height, body mass, and five skinfolds were measured by the same investigators in both instances. Overweight and obesity were estimated by using BMI (Cole et al., 2000), respectively skinfold thicknesses (Parízková, 1961).The pair-wise differences between height means were consistently significant in the 12 age groups studied. Body mass differences were not exactly proportionate with height. The boys of 2005 had significantly more relative body fat than those of 1980. The prevalence of overweight and obesity was remarkably higher in 2005.Taller height and a part of the heavier body mass in 2005 was attributed to a positive secular growth trend. The increases in BMI and fat content are negative consequences of a markedly changed lifestyle associated with inactivity and dietary habits. Because of its public health importance the trends of childhood obesity should be closely monitored. 相似文献
186.
Biró E Németh AS Sisak C Feczkó T Gyenis J 《Journal of biochemical and biophysical methods》2008,70(6):1240-1246
Macro-, micro- and nanosized chitosan particles suitable as immobilization carriers were prepared by precipitation, emulsion cross-linking and ionic gelation methods, respectively. Effects of particle preparation parameters on particle size were investigated. Activities of β-galactosidase covalently attached to differently sized particles have been evaluated and compared. The highest activity was shown by the biocatalyst immobilized on nanoparticles obtained by means of the ionotropic gelation method with sodium sulphate as gelation agent. β-Galactosidase fixed on macro- and microspheres exhibited excellent storage stability in aqueous solution, with no more than 5% loss of activity after 3 weeks storage at 4 °C and pH 7.0. 相似文献
187.
188.
Eden Ephraim Agnes Odenyo Mogessie Ashenafi 《World journal of microbiology & biotechnology》2005,21(6-7):803-809
Summary Tannins limit the use of fodder trees as feed for ruminants. Removal of the effects of tannins would thus improve the nutritional
quality of these trees. This prompted the study to evaluate the effect of rumen or faecal mixed cultures from different animals
on tannin degradation. Tannin extracts, tannic acid and gallic acid were used to enrich media to assess if rumen or faecal
mixed cultures could degrade the phenolic compounds. Rumen fluid of Acacia-adapted sheep, sheep fed on wheat bran, bush duikers (Sylvicapra grimmia) and goats fed on Leucaena pallida and Sesbania goetzei were separately inoculated into Growth Study Medium (GSM) and incubated for 5-15 days. Faecal samples from dikdik (Madoqua guentheri), camel (Camelus dromedarius), zebra (Equus quagga), Grant’s gazelle (Gazella granti) and hartebeest (Alcelaphus buselaphus) were also separately inoculated into GSM media and incubated from 3-5 days. TLC results showed that mixed cultures from
rumen fluids of Acacia-adapted sheep, sheep on wheat bran, goats on Leucaena pallida and Sesbania goetzei partially hydrolysed tannic acid to pyrogallol. Complete degradation of the heterocyclic ring in tannic acid and gallic acid
was achieved by the mixed cultures from the faecal samples of dikdik and this was confirmed by HPLC. Mixed cultures from faecal
samples of camel hydrolysed gallic acid to phloroglucinol. This study has demonstrated that faecal microorganisms of Ethiopian
dikdik could completely degrade hydrolysable tannin. 相似文献
189.
A comparison of cDNA, oligonucleotide, and Affymetrix GeneChip gene expression microarray platforms.
Yong Woo Jason Affourtit Sandra Daigle Agnes Viale Kevin Johnson Jurgen Naggert Gary Churchill 《Journal of biomolecular techniques》2004,15(4):276-284
We have conducted a study to compare the variability in measured gene expression levels associated with three types of microarray platforms. Total RNA samples were obtained from liver tissue of four male mice, two each from inbred strains A/J and C57BL/6J. The same four samples were assayed on Affymetrix Mouse Genome Expression Set 430 GeneChips (MOE430A and MOE430B), spotted cDNA microarrays, and spotted oligonucleotide microarrays using eight arrays of each type. Variances associated with measurement error were observed to be comparable across all microarray platforms. The MOE430A GeneChips and cDNA arrays had higher precision across technical replicates than the MOE430B GeneChips and oligonucleotide arrays. The Affymetrix platform showed the greatest range in the magnitude of expression levels followed by the oligonucleotide arrays. We observed good concordance in both estimated expression level and statistical significance of common genes between the Affymetrix MOE430A GeneChip and the oligonucleotide arrays. Despite their apparently high precision, cDNA arrays showed poor concordance with other platforms. 相似文献