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971.
Amar S Ecke W Becker HC Möllers C 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,116(8):1051-1061
Improving oil and protein quality for food and feed purposes is an important goal in rapeseed (Brassica napus L.) breeding programs. Rapeseed contains phytosterols, used to enrich food products, and sinapate esters, which are limiting
the utilization of rapeseed proteins in the feed industry. Increasing the phytosterol content of oil and lowering sinapate
ester content of meal could increase the value of the oilseed rape crop. The objective of the present study was to identify
quantitative trait loci (QTL) for phytosterol and sinapate ester content in a winter rapeseed population of 148 doubled haploid
lines, previously found to have a large variation for these two traits. This population also segregated for the two erucic
acid genes. A close negative correlation was found between erucic acid and phytosterol content (Spearman’s rank correlation,
r
s = −0.80**). For total phytosterol content, three QTL were detected, explaining 60% of the genetic variance. The two QTL with the strongest
additive effects were mapped on linkage groups N8 and N13 within the confidence intervals of the two erucic acid genes. For
sinapate ester content four QTL were detected, explaining 53% of the genetic variance. Again, a close negative correlation
was found between erucic acid and sinapate ester content (r
s = −0.66**) and the QTL with the strongest additive effects mapped on linkage groups N8 and N13 within the confidence intervals of the
two erucic acid genes. The results suggests, that there is a pleiotropic effect of the two erucic acid genes on phytosterol
and sinapate ester content; the effect of the alleles for low erucic acid content is to increase phytosterol and sinapate
ester content. Possible reasons for this are discussed based on known biosynthetic pathways.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
972.
Airong Li Yue Zhu Xingbing He Xingjun Tian Liang Xu Wu Ni Ping Jiang 《World journal of microbiology & biotechnology》2008,24(4):569-572
Six selected plants, belonging to 3 families from Nanjing of China, were extracted with the solvent 95% (v/v) ethanol to yield
11 extracts. The extracts were evaluated for their effects on the growth of eight clinical bacteria, two fungi and one yeast
using a modified agar diffusion method. The results showed that the majority of the extracts investigated showed greater activities
against the Gram-positive bacteria than against the Gram-negative bacteria, the fungi and the yeast. The strongest antimicrobial
activity was exhibited by the stem extracts of Mahonia fortunei against multiresistant Staphylococcus aureus strains, followed by the stem extracts of Mahonia bealei, while Bacillus thuringiensis was the most sensitive to all extracts. 相似文献
973.
Irina Vaseva Dessislava Todorova Jiří Malbeck Alena Trávníčková Ivana Macháčková 《Acta Physiologiae Plantarum》2008,30(2):151-155
Changes in cytokinin pool and cytokinin oxidase/dehydrogenase activity (CKX EC: 1.5.99.12) in response to increasing abscisic
acid (ABA) concentrations (0.5–10 μM) were assessed in the last fully expanded leaves and secondary roots of two pea (Pisum sativum) varieties with different vegetation periods. Certain organ diversity in CKX response to exogenous ABA was observed. Treatment
provoked altered cytokinin pool in the aboveground parts of both studied cultivars. Specific CKX activity was influenced significantly
basically in roots of the treated plants. Results suggest that ABA-mediated cytokinin pool changes are leaf-specific and involve
certain root signals in which CKX activity presents an important link. This enzymatic activity most probably regulates vascular
transport of active cytokinins from roots to shoots. 相似文献
974.
Yurixhi Maldonado–López Edelmira Linares–Mazari Robert Bye Guillermo Delgado Francisco J. Espinosa–García 《Economic botany》2008,62(2):161-170
Mexican Arnica Anti–Inflammatory Action: Plant Age Is Correlated with the Concentration of Anti–inflammatory Sesquiterpenes
in the Medicinal Plant
Heterotheca inuloides
Cass. (Asteraceae). Mexican árnica (Heterotheca inuloides Cass.) is a widely used anti–inflammatory medicinal plant in Mexican folk medicine. Although it has been suggested that plant
age, fertilization, and harvesting regime influence the concentration of secondary compounds affecting the therapeutic activity
of the plant, the effect of these variables on the concentration of the Mexican árnica anti–inflammatory compounds was not
known. We quantified anti–inflammatory sesquiterpenes (caryolan–1, 9β–diol, cadalen–15–oic acid, 7–hydroxycadalene, 4–hydroxy–2–isopropyl–4,
7–dimethyl–1[4H] naftalinone, 7–hydroxy–4αH–3, 4–dihydrocadalene, β–caryophyllene, and β–caryophyllene epoxide) in Mexican
árnica plants subjected to fertilization and successive harvests of flowering stems, conditions that mimic the cultivation
and harvesting for árnica in México. Fertilization and successive harvesting and their interaction had no significant effect
on the concentration of anti–inflammatory compounds. However, the concentrations of these compounds were 60% higher in flowering
stems from 15–month–old plants than in those from 4– or 8–month–old plants and was independent of the number of harvests and
fertilization regime applied. 相似文献
975.
Raşit Urhan 《Biologia》2008,63(3):395-401
Two new species of zerconid mites, Zercon uludagicus sp. n. and Z. huseyini sp. n., from Turkey are described and illustrated. The similarities and differences between the species are discussed. The
lists of the taxonomic diagnostic key to adults of Zercon species known from Turkey are also given. 相似文献
976.
977.
Amornrat Chumthong Mana Kanjanamaneesathian Ashara Pengnoo Ruedeekorn Wiwattanapatapee 《World journal of microbiology & biotechnology》2008,24(11):2499-2507
Endospores of B. megaterium were formulated in granule formulations with sodium alginate, lactose and polyvinylpyrrolidone (PVP K-30) by the wet granulation
technique. The granule formulation exhibited good physical characteristics, such as high-water solubility and optimal viscosity,
that would be suitable for spray application. The bacteria remained viable in the dry granule formulation at 109 c.f.u./g after 24 months storage at room temperature. Under laboratory conditions, aqueous solutions of the formulation showed
high activity against mycelial growth of R. solani (99.64 ± 0.14% mycelial inhibition). High viability of the bacterial antagonist on leaf sheath and leaf blade at day 7 after
spraying with the formulation was observed (approximately 106 c.f.u./g of plant). Application of an equivalent number of un-formulated endospores resulted in much loss of the bacterial
endospores even 1 day after application. In a small pilot field study, an aqueous solution of the formulation (3%w/v) applied
by spraying at days 1, 5 and 10 after pathogen inoculation of the rice plants was more effective in suppressing rice sheath
blight disease than one application of a fungicide (Iprodione) at day 1. Additionally, rice plants sprayed with the aqueous
solution of the granule formulation had higher panicle and whole kernel weights than those of fungicide-treated and control
(untreated) plants. 相似文献
978.
Abstract: Stores of methionine-enkephalin were labelled on the N -terminal by incubation of whole brain slices with [3 H]tyrosine (10 °Ci/ml). The 3 H radioactivity corresponding to the position of authentic Met-enkephalin after extraction on Amberlite XAD2 and separation by thin-layer chromatography was taken as an index of synthesis. Maximal incorporation of the labelled tyrosine into Met-enkephalin was attained after 4 h of incubation at 37°C and was inhibited in the presence of 10 μ M cycloheximide. Isolated nerve terminals failed to incorporate any [3 H]tyrosine. The labelled compound had opiatelike activity and consisted of the same five amino acids as an authentic standard. Incubations with leucine aminopeptidase indicated that the labelled tyrosine was on the N -terminus and removal of this tyrosine resulted in loss of opiate-like activity. The incorporation of [14 C]glycine, selected as an alternative precursor, was consistent with de novo synthesis and not N -terminal exchange. A radioimmunoassay was also used to quantify the amount of labelled Met-enkephalin. KCl (50 m M ) elicited a Ca2+ -dependent release of the synthesised [3 H]Met-enkephalin from whole brain slices and also from isolated nerve terminals. The release of Met-enkephalin radioimmunoactivity paralleled that of [3 H]met-enkephalin. Preliminary investigations have suggested that carbamyl choline inhibited this release and its effect was partially reversed by atropine. 相似文献
979.
Behavioral and adrenocortical reactivity to stressful stimulation was examined in 12- and 13-day-old chicks of two lines of Japanese quail selected over several generations for exaggerated (HS: high stress) or reduced (LS: low stress) plasma corticosterone (B) response to brief immobilization stress. Plasma B concentrations and tonic immobility (TI) fear reactions were measured in unstressed (control) and stressed (overnight cooping) chicks of both lines. The stress treatment was applied over a period of 12-20 hr and it involved capture by the experimenter, inescapable exposure to an unfamiliar environment and to strange conspecifics, reductions in ambient temperature and floor space, and the deprivation of food and water. Chicks of the HS line were more susceptible to the induction of TI and they remained immobile longer than did LS chicks. Therefore HS chicks were considered to be more fearful than their LS counterparts. Stress treatment elicited a marked adrenocortical response that was more pronounced in HS than in LS chicks. Stress treatment also increased susceptibility to TI but did not significantly affect the duration of immobility. These findings suggest that selecting the quail for differential corticosterone response to a particular stressor had exerted an unconscious and concomitant effect on underlying fearfulness as well as on their adrenocortical reactivity to several other stressful situations. The results are further discussed in terms of a putative relationship between adrenocortical activation and fearfulness. 相似文献
980.
Three major low-pI zones of aldehyde dehydrogenase (aldehyde:NAD+ oxidoreductase, EC 1.2.1.3) may be visualized with specific histochemical staining after starch gel electrophoresis at pH 7.4 of Caucasian human liver extracts, whereas about 50% of Chinese human liver extracts show only two such zones. The three zones of activity were purified to apparent homogeneity from Caucasian liver. The substrate specificity of each form was investigated by double reciprocal plots using 13 aldehydes of various chemistries. The acetaldehyde-preferring isozyme I lacking in 50% of Chinese livers had a slightly lower native and subunit molecular weight than the "universal' isozymes IIa and IIb. All forms were highly sensitive to disulfiram inhibition. This inhibition could be protected against, or reversed, by dithiothreitol. 2,2'-Dithiodipyridine was a slower inhibitor of isoenzyme I. All three purified forms of the enzyme, as well as crude extracts of normal and isozyme I-deficient Chinese livers, showed positive immunoreactivity to antibodies prepared in rabbits against type I enzyme. Tryptic peptide maps of forms IIa and IIb were almost identical, whereas that of form I, although showing some similarities, was clearly different. These results provide a consistent explanation for the acetaldehyde-mediated extreme sensitivity to moderate alcohol ingestion shown normally by about 50% of oriental subjects and during disulfiram (Antabuse) therapy by all subjects. 相似文献