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81.
A. Yu. Dragovich V. G. Zima A. V. Fisenko L. A. Bespalova G. I. Bukreeva E. E. Mel’nikova N. I. Shchipkova V. A. Pukhalskiy 《Russian Journal of Genetics》2006,42(8):915-923
Two catalogs of alleles of gliadin-coding loci, controlling synthesis of a storage protein of wheat caryopsis, gliadin, were compared. One catalog comprises the alleles detected according to the electrophoretic patterns in starch gels; the other, in polyacrylamide gels. Determination of the allelic state of gliadin-coding loci in 31 previously not studied cultivars of winter common wheat allowed us to construct a matching system for the alleles compiled in the two catalogs, which gives the possibility to compare the results of wheat cultivar analyses performed at different scientific institutions. 相似文献
82.
V. K. Rybal’chenko G. V. Ostrovskaya I. V. Poralo T. V. Rybal’chenko Yu. M. Mel’nik 《Neurophysiology》1999,31(3):223-225
On modeled monolayer phospholipid (formed from azolectin) membranes, we studied the surface activity of optical isomers of
a dipeptide, kyotorphin (Tyr-Arg), and a cardiotonic agent, suphan (N-succinyltryptophan potassium salt). It was found that
the membranotropic activity of four studied isomers of kyotorphin is distributed in the order: LL>DL≈LD>DD, and two isomers
(by tryptophan) of suphan as LL>DL. The data obtained suggest that the primary mechanism underlying binding of kyotorphin
and suphan to the plasma membrane can be considered based on interaction of their molecules with the molecules of membrane
phospholipids. Binding of molecules of kyotorphin and suphan by the lipid matrix to the plasma membrane and/or their incorporation
into the matrix is a result of the above interaction. 相似文献
83.
The binding of chlorpromazine · HCl at the human erythrocyte surface has been detected through its effect on cellular electrophoretic mobility. Incubation of erythrocytes (approx. 5 · 106/ml) in 23 μM chlorpromazine · HCl resulted in a reduction of negative electrophoretic mobility from the control value of (μm · s?1)/(V · cm?1) to (μm · s?1)/(V · cm?1) (pH 7.2, ionic strength 0.155). This mobility change was completely reversed when chlorpromazine · HCl was removed by centrifugal washing. Increasing the drug concentration to 70μM did not affect the mobility change, indicating saturation of the electrophoretically detectable drug binding sites over chlorpromazine · HCl concentration range studied here. The effect of the 23 μM chlorpromazine · HCl on electrophoretic mobility was also measured in isotonic media of reduced ionic strength. The drug-induced reduction in negative surface charge density was found to be independent of ionic strength over the range 0.155 (Debye length, 0.8 nm) to 0.00310 (Debye length, 5.7 nm).Fixation of erythrocytes with glutaraldehyde affected neither the normal electrophoretic mobility of discocytes nor the reduced electrophoretic mobility of chlorpromazine · HCl-induced stomatocytes. When these stomatocytes were first fixed with glutaraldehyde, then washed free of chlorpromazine · HCl, they retained the stomatocyte form while regaining a normal control electrophoretic mobility. Conversely, when discocytes fixed in that form were treated with chlorpromazine · HCl, they showed the same mobility change as did fixed or unfixed stomatocytes. The drug-induced mobility change is therefore independent of the shape change, but reflects a contribution to cellular surface charge density from the membrane-bound chlorpromazine · HCl molecules. From the charge reduction, it is estimated that about 106 chlorpromazine · HCl molecules are bound at the electrokinetic cell surface and occupy approximately 0.4% of the total surface area. 相似文献
84.
85.
Diversity of Tabanidae,Asilidae and Syrphidae (Diptera) in natural protected areas of Yucatan,Mexico
Abdiel Martín-Park Hugo Delfín-González Paula Sosenski Enrique Reyes-Novelo Virginia Meléndez-Ramírez Juan Navarrete-Carballo Sergio Ibáñez-Bernal Felipe Dzul-Manzanilla Alejandra González-Moreno Pablo Manrique-Saide 《Journal of Insect Conservation》2018,22(1):85-97
Although dipteran communities play a fundamental role in the ecosystem, little is known about their diversity, richness and abundance in different environments. In spite of the importance of Natural Protected Areas (NPAs) as reservoirs of biological diversity, information about community parameters of most insects, including Diptera, are practically unknown in these areas. In this study, we described and compared the composition and structure of Dipteran communities (considering Tabanidae, Asilidae and Syrphidae families) within six (NPAs) of Yucatan, Southeast Mexico, comprising four main vegetation types: seasonally flooded forest, tropical deciduous forest, semi-deciduous tropical forest and coastal dune. We used Malaise-traps to collect samples during a period of two days, twice a month, for one year (2006–2007) within each NPAs. A total of 6 910 specimens belonging to 33 genera and 78 species/morphospecies were recorded. Our results show that the four vegetation types host a vast diversity of dipterans. However, species richness, abundance, diversity and similarity were higher in the communities of tropical deciduous forests compared with those from semi-deciduous forests and coastal dune vegetation, probably as a result of microhabitat differences between sites. We highlight the role of tropical deciduous forests as a refuge for Diptera species and the importance of these forests for conservation of dipteran communities. 相似文献
86.
Maureen P. Martin Anita Harding Robert Chadwick Mel Kronick Michael Cullen Ling Lin Emmanuel Mignot M. Carrington 《Immunogenetics》1997,47(2):131-138
The human genome contains a large number of interspersed microsatellite repeats which exhibit a high degree of polymorphism
and are inherited in a Mendelian fashion, making them extremely useful genetic markers. Several microsatellites have been
described in the HLA region, but allele nomenclature, a set of broadly distributed controls, and typing methods have not been standardized, which
has resulted in discrepant microsatellite data between laboratories. In this report we present a detailed protocol for genotyping
microsatellites using a semi-automated fluorescence-based method. Twelve microsatellites within or near the major histocompatibility
complex (MHC) were typed in the 10th International Histocompatibility Workshop homozygous typing cell lines (HTCs) and alleles
were designated based on size. All loci were sequenced in two HTCs providing some information on the level of complexity of
the repeat sequence. A comparison of allele size obtained by genotyping versus that obtained by direct sequencing showed minor
discrepancies in some cases, but these were not unexpected given the technical differences in the methodologies. Fluorescence-based
typing of microsatellites in the MHC described herein is highly efficient, accurate, and reproducible, and will allow comparison
of results between laboratories.
Received: 10 May 1997 / Revised: 1 August 1997 相似文献
87.
Mel Chih-Yu Chu 《American journal of botany》1974,61(7):681-692
A comparative study of the leaves of 31 species of Lycopodium was made. The pattern of tracheids varies with the species. Usually they exhibit annular, helical, reticulate, modified or transition forms; none of the species have advanced phylogenetically beyond the scalariform tracheid stage. Mucilage canals have been found in four species. Tracheids are enclosed by a few to several layers of oblique ended, elongated parenchyma cells in most species, but an endodermis is absent. Vascular bundles are encircled by fiber cells in three species. The mesophyll of most species consists of identically shaped cells, although palisade-like tissue has been observed in a few species. The epidermal cells vary from elongated to isodiametric and have either undulated or smooth anticlinal walls, which are deeply pitted in some species. The outer epidermal walls are usually thick and heavily cutinized. Stomates are distributed on both surfaces in 18 species, on the abaxial surface in 11 species, and on the adaxial side in only two species. Most stomates are practically isodiametric in surface view, broader than epidermal cells, usually parallel to the vein, and at the same level as the adjacent epidermal cell. A typical guard cell has a prominent outer ledge and a less developed inner ledge of cutin in most species. Six groupings are suggested, based on similarity of leaf structure and the known chromosome numbers. 相似文献
88.
89.
90.
Alexander D. Dergunov Anne Ponthieux Maxim V. Mel’kin Daniel Lambert Sophie Visvikis-Siest Gerard Siest 《Molecular and cellular biochemistry》2009,325(1-2):41-51
Sixteen patients differing widely in plasma triglyceride content were divided into three groups by their apolipoprotein E (apoE) phenotype—E33 homozygotes, E23, and E34 heterozygotes. The plasma lipid and apoE distribution between individual lipoproteins was followed by capillary isotachophoresis (CITP) of plasma samples pre-stained with lipid fluorescent probe NBD-C6-ceramide and by fluorescein-labeled apoE, respectively. Among 12 peaks visualized by ceramide staining, an individual peak with very low density lipoproteins (VLDL) was identified. The VLDL cholesterol and apoE content determined by CITP directly in whole plasma were significantly related to their content as determined by conventional analysis with isolated VLDL. The ceramide distribution among lipoprotein pools was insensitive to apoE phenotype (49–53 : 7–11 : 39–43% for HDL, VLDL, and IDL/LDL, respectively) while the preferential binding of apoE to VLDL was observed in E34 patients compared to E33 (62 : 19 : 20 vs. 70 : 9 : 22%). In a study of apoE/F displacement from lipoproteins at plasma titration by apoC-III in vitro, apoE was found to bind more tightly to VLDL from E34 compared to E33 patients as evidenced by both the increased non-displaceable apoE pool, the increased VLDL sorbtion capacity for apoE, and the decreased displacement parameter in a “container” model of lipoprotein binding. Two different types of apoE package in a whole lipoprotein profile were observed. ApoE structure in a particular lipoprotein may underlie the phenotype-sensitive apoE distribution and apoC-III interference in hypertriglyceridemia. 相似文献