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391.
CJ Cooksey 《Biotechnic & histochemistry》2013,88(2):105-125
This bibliography lists and comments on publications describing the history, preparation, chemistry and some applications of indigo and related dyes. Note that the commentary by the author is in italics after the bibliographic information. 相似文献
392.
Managed fallows which recover nutrients more rapidly than natural secondary vegetation may improve the performance of shifting
agriculture systems operating under inadequately long fallow cycles. Our objective was to construct nutrient balances for
the soil, vegetation, and litter compartments of six planted leguminous fallows and natural secondary vegetation during 53
months. The fallows were planted on a previously cultivated Ultisol (Acrisol) in the Peruvian Amazon and included:Centrosema macrocarpum (Centrosema),Pueraria phaseoloides (Pueraria),Stylosanthes guianensis (Stylosanthes),Desmodium ovalifolium (Desmodium),Cajanus cajan (Cajanus), andInga edulis (Inga). In addition, in the natural fallow treatment secondary vegetation was allowed to establish and grow naturally. Quantities
of extractable P, K, Ca, and Mg, total N, and organic C in soil to a 45 cm depth, and macrouttrients in aboveground biomass,
roots, and litter were estimated at fallow planting, at 8, 17, and 29 months afterward, and at fallow clearing (53 months).
Total N stocks increased by 10% in the Stylosanthes, Desmodium, Pueraria, and Inga treatments, but changed little in the Cajanus,
Centrosema and natural fallows. This difference was largely due to greater net increases in both soil and vegetation compartments
in the former group of treatments. In the Inga, Desmodium, and natural fallows, total stocks of P and K at 53 months were
about 40% to 80% greater and 12% greater, respectively, than initial values, but Ca and Mg stocks were reduced by 25% to 40%.
In the other treatments, there was generally little change in P stocks, but large (30% to 60%) reductions in K, Ca, and Mg
during the course of the fallow. Although there were net decreases of stocks of P, K, Ca, and Mg in soil in all treatments
during the fallow, storage of P and K in vegetation and litter in the Inga, Desmodium, and natural fallows offset losses of
these nutrients from soil. These treatments also tended to accumulate more Ca and Mg in biomass and litter than the other
treatments. These results suggest that leguminous fallow vegetation that accumulates large amounts of biomass may increase
N, P, and K stocks, but that incomplete recuperation of Ca and Mg may limit the sustainability of short-rotation fallow-based
systems on acidic, infertile soils. ei]Section editor: G R Stewart 相似文献
393.
The Mongolian gerbil is commonly used in medical research. Intravenous administration of compounds in gerbils is difficult as tail vein injection sites are not visible. The present study describes a method for intravenous administration into the jugular vein in Mongolian gerbil by using an 'over-the-needle' catheter under anaesthesia. The catheter penetrates the pectoral muscle and is easily inserted into the vein. The method is simple and avoids extensive surgery in the animals. 相似文献
394.
Polymerase chain reaction (PCR) gut analysis was conducted on specimens of the introduced spider Tenuiphantes tenuis collected from dairy pasture in Canterbury, New Zealand. PCR primers were specifically designed to amplify a fragment of the mitochondrial gene cytochrome c oxidase subunit 1 (COI) from Listronotus bonariensis and revealed that this major pasture pest species is consumed in the field by T. tenuis. The field predation rate of L. bonariensis by T. tenuis was estimated from our PCR results together with published data on the degradation of DNA and the density of T. tenuis in Canterbury pastures. We found that T. tenuis is a potentially significant predator of L. bonariensis in New Zealand pastures. 相似文献
395.
This study investigates oxidative stress and antioxidants in normal human pregnancy and post-partum period. Thirty-seven healthy women with normal pregnancies were included. Both urinary and serum samples were collected throughout the pregnancy and post-partum period. Oxidative stress was estimated by measuring the reliable in vivo marker, namely 8-iso-prostaglandin F2α (8-iso-PGF2α, an F2-isoprostane) and antioxidant status was evaluated by measuring α- and γ-tocopherol in serum samples. Pregnancy was associated with successively increased levels of 8-iso-PGF2α with advancing gestational age. The median post-partum value corresponded to the values observed in early gestation and a significant decrease was observed from late pregnancy to the post-partum period. Lipid-adjusted α- and γ-tocopherol levels decreased with advancing gestational age. This longitudinal study suggests that mild oxidative stress is involved in normal human pregnancy. 相似文献
396.
Separation and characterization of modified variants of recombinant human insulin-like growth factor I derived from a fusion protein secreted from Escherichia coli. 总被引:1,自引:0,他引:1 下载免费PDF全文
Human insulin-like growth factor I, IGF-I, was produced in Escherichia coli fused to a synthetic IgG-binding peptide The fusion protein is secreted into the medium during fermentation and was initially purified on an IgG-Sepharose column. After hydroxylamine cleavage, IGF-I was purified to homogeneity. During purification, impurities in the form of modified variants of IGF-I were detected and characterized. The closely related impurities were identified to be a misfolded form of IGF-I, having mismatched disulphide bonds, a form with the single methionine residue in IGF-I oxidized to methionine sulphoxide and a variant in which the methionine residue was substituted by a norleucine residue during protein synthesis. A form proteolytically cleaved between two arginine residue was also detected. These impurities were separated from the major component, native IGF-I, by using reverse-phase h.p.l.c. The modified molecules as well as native IGF-I were characterized both as intact molecules and as fragments, after pepsin digestion, using the techniques of plasma desorption m.s., N-terminal sequencing and amino acid analysis. The oxidized form was 90%, and the norleucine analogue was 70%, as potent as native IGF-I in a biological radioreceptor assay, and the form having mismatched disulphides lacked receptor affinity. 相似文献
397.
Concordance of allozyme and microsatellite differentiation in a marine fish, but evidence of selection at a microsatellite locus 总被引:3,自引:1,他引:3
Previous studies have reported higher levels of divergence for microsatellites than for allozymes in several species, suggested to reflect stabilizing selection on the allozymes. We compared the differentiation patterns of 11 allozyme and nine microsatellite loci using 679 spawning Atlantic herring (Clupea harengus) collected in the Baltic and North Seas to test for differential natural selection on these markers. Observed distributions of F statistics for the two types of markers are conspicuously dissimilar, but we show that these differences can largely be explained by sampling phenomena caused by different allele frequency distributions and degrees of variability. The results show consistently low levels of differentiation for both marker types, with the exception of one outlier microsatellite locus with a notably high F(ST). The aberrant pattern at this locus is primarily due to two alleles occurring at markedly high frequencies in the Baltic, suggesting selection at this locus, or a closely linked one. When excluding this locus, the two marker types show similar, weak differentiation patterns with F(ST) values between the Baltic and the North Seas of 0.001 and 0.002 for allozymes and microsatellites, respectively. This small heterogeneity, and weak isolation by distance, is easier to distinguish statistically with microsatellites than with allozymes that have fewer alleles and skewed frequency distributions. The allozymes, however, also detect surprisingly low levels of divergence. Our results support suggestions that previously described differences between marker types are primarily caused by a small number of outlier loci. 相似文献
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