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131.
132.
Identification of sex in Cetaceans by multiplexing with three ZFX and ZFY specific primers 总被引:12,自引:0,他引:12
We sequenced 540 nucleotides of the last exon in the ZFY/ZFX gene in two males and two females for eight cetacean species; four odontocetes (toothed whales) and four mysticetes (baleen whales). Based upon the obtained nucleotide sequences, we designed two sets of oligonucleotide primers for specific amplification of the ZFX and the ZFY sequence in odontocetes and mysticetes, respectively. Each primer set consisted of three oligonucleotides; one forward-orientated primer, which anneals to the ZFY as well as the ZFX sequence, and two reverse-orientated primers that anneal to either the ZFX or the ZFY sequence. The resulting two amplification products (specific for the ZFY and ZFX sequences) can be distinguished by gel-electrophoresis through 2% NuSieve™. The accuracy of the technique was tested by determination of gender in 214 individuals of known sex. Finally we applied the technique to determine the sex of 3570 cetacean specimens; 2284 humpback whales, 315 fin whales, 37 blue whales, 7 minke whales, as well as 592 belugas, 335 narwhals and 25 harbour porpoises. 相似文献
133.
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135.
PLANT GROWTH RESPONSES TO VESICULAR-ARBUSCULAR MYCORRHIZA 总被引:4,自引:4,他引:0
CONWAY LL. POWELL 《The New phytologist》1975,75(3):563-566
136.
Leaf Development in Lolium temulentum L.: Progressive Changes in Soluble Polypeptide Complement and Isoenzymes 总被引:3,自引:0,他引:3
OUGHAM HELEN J.; JONES THOMAS W. A.; EVANS MAIR LL. 《Journal of experimental botany》1987,38(10):1689-1696
Ougham, Helen J., Jones, Thomas W. A. and Evans, Mair LL. 1987.Leaf development in Lolium temulentum L.: progressive changesin soluble polypeptide complement and isoenzymes.J. exp.Bot. 38: 16891696. The spectrum of soluble polypeptides extracted from segmentsof the developing 4th leaf of Lolium temulentum simplified withincreasing distance from the leaf base. Most of the metabolicallyimportant isoenzymes analysed also exhibited gradients of activitywith respect to distance from the base, and in some cases twoor more contrasting gradients were observed for a given enzyme. Key words: Gradients, isoenzymes, leaves, Lolium temulentum,, soluble polypeptides 相似文献
137.
The effects of application of nitrogen as calcium nitrate, urea or ammonium sulphate at two rates through the trickle irrigation
system on pH and nutrient status of the wetted volume of soil below the emitters and on growth and nutrition of courgette
(zucchini) plants (Cucurbita pepo L.) was investigated.
Soil acidification, caused by nitrification, occurred to a large extent in the volume of soil immediately below the emitters
in the urea and ammonium sulphate treatments. Acidification was greater at the high rate of N addition and more pronounced
with ammonium sulphate than urea. A significant amount of applied urea appeared to move through the soil as urea and consequently,
at the same rate of N addition, levels of ammonium were lower directly below the emitter and those of nitrate were higher
further away from the emitters for the urea than ammonium sulphate treatments. Soil acidification below the emitters resulted
in significant decreases in levels of exchangeable Ca, Mg and K and increases in levels of exchangeable Al, EDTA-extractable
Fe, Mn, Zn and Cu and bicarbonate-extractable P.
Vegetative growth and harvestable yields of courgettes were increased by both irrigation and nitrogen applications. Vegetative
growth was generally greater at the low rate of N addition than at the high one and generally followed the order calcium nitrate
> urea > ammonium sulphate. However, fruit yields followed the order urea > ammonium sulphate > calcium nitrate and were larger
at the high rate of N for urea and ammonium sulphate treatments and unaffected by rate for the calcium nitrate treatments.
It is suggested that with fertigation, the form of applied N can have significant physiological effects of plant growth and
yields because N may be applied into the root zone on numerous occasions during the growing season. 相似文献
138.
N6-Trimethyl-lysine metabolism. Structural identification of the metabolite 3-hydroxy-N6-trimethyl-lysine 下载免费PDF全文
1H and 13C nuclear-magnetic-resonance spectroscopy and functional-group analysis were used to determine the molecular structure of an isolated metabolite (IIb) of trimethyl-lysine as 3-hydroxy-N6-trimethyl-lysine, an important intermediate in the conversion of trimethyl-lysine into trimethylammoniobutyrate and carnitine [Hoppel, Cox & Novak (1980) Biochem. J. 188, 509–519]. Functional-group analysis revealed the presence of a primary amine and reaction of metabolite (IIb) with periodate yielded 4-N-trimethylammoniobutyrate as a product, showing 2,3-substitution on the molecule and suggesting that the 3-substitution on the molecule may be an alcohol ([unk]CH–OH), amine ([unk]CH[unk]–NH2) or carbonyl ([unk]C=O) functional group. 1H integration ratios, 1H and 13C chemical-shift data and 1H and 13C signal multiplicities from the sample (IIb) were used to complete the identification of metabolite (IIb) as 3-hydroxy-N6-trimethyl-lysine. For example, the proton multiplet at δ 4.2p.p.m. and doublet at δ 4.1p.p.m., positions representative of amine or alcohol substitution on methylene carbon atoms, integration ratios of 1:1:2:9:4 and a positive ninhydrin test suggest 3-hydroxy-N6-trimethyl-lysine as the molecular structure for metabolite (IIb). 13C chemical-shift data obtained from the sample (IIb) and compared with several model compounds (trimethylammoniohexanoate, trimethyl-lysine and 3-hydroxylysine) resulted in generation of the spectrum of the metabolite and allowed independent identification of metabolite (IIb) as 3-hydroxy-N6-trimethyl-lysine. The 1H spectrum of erythro- and threo-3-hydroxylysine are presented for comparison, and the 1H and 13C n.m.r. spectra of the erythro-isomer support this analysis. 相似文献
139.
We have examined aspects of the bioluminescence of 5 clones of Dissodinium, 1 clone of Pyrocystis acuta, 4 clones of Pyrocystis fusiformis, and 5 clones of Pyrocystis noctiluca. All clones produced the same color bioluminescence with an intensity peak near 474 nm. The in vivo emission spectra of these clones agreed with those previously determined, for 4 other species of marine dinoflagellates. The amount of light emitted by the dinoflagellates in scotophase when mechanically stimulated to exhaustion was determined for most of the clones. The largest species, P. noctiluca and P. fusiformis, emitted 37–89 × 109 photons cell?1 and 23–62 × 109 photons cell?1, respectively, about a thousand, times as much light as Gonyaulax species. Pyrocystis acuta emitted 3–6 × 109 photons cell?1. Three of the 5 clones of Dissodinium were bioluminescent. The range for 3 clones was 5–13 × 109 photons cell?1. All 5 clones of Dissodinium are morphologically distinct. Both the clones of Dissodinium and Pyrocystis produced much higher numbers of photons per cell nitrogen (ca. 7–50 times) than Gonyaulax polyedra or Pyrodinium bahamense. The data suggested that enzyme turnover occurred in the reactions producing light during mechanical stimulation of Dissodinium and Pyrocystis species. 相似文献
140.
Elijah Swift 《Journal of phycology》1973,9(4):456-460
Living cells of the diatom Ethmodiscus rex (Rat-Iray) Wiseman & Hendey 1953 were found in the plankton of the southern Sargasso Sea. Apparently, this is the first report, of E rex from the plankton of the Atlantic Ocean. Scanning electron microscopy of peroxide-cleaned frustules revealed, some new morphological features for this species. When viewed, from inside the frustule, the puncta appear as rimmed pits. From outside the frustule, they appear to he shallow depressions with a small opening at the bottom. The so-called mucous tubules in the center of the valve were seen from the out side to be elongate slits and from the inside as obliquely directed flattened cylinders which cap the tubes. 相似文献