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181.
Gingivitis is the most common form of oral disease especially among patients undergoing fixed orthodontic treatment. Green tea, which is extensively used in Asian countries, can help to improve the overall gingival health, which can be assessed by using the gingival indices. Evaluation of the effectiveness of green tea on the gingival health of patients undergoing Orthodontic treatment is of interest. 40 otherwise healthy patients undergoing fixed orthodontic treatment were randomly divided in two groups namely (1) study group and (2) control group. Gingival indices were scored for all the patients. Study group was given mouth rinse with green tea extract and control group was given placebo with no green tea extract. Gingival indices were measured for all the patients after 21 days. Mann Whitney U test and Wilcoxon test was used for statistical analysis. The gingival indices scoring in which the values before and after the use of mouthwash were compared. The p value was found to be statistically significant (p<0.05) in study group. But in control group statistical significant could not be reached. 相似文献
182.
Christian Boedeker Anja Eggert Anne Immers Isamu Wakana 《Journal of Biogeography》2010,37(8):1491-1503
Aim Aegagropila linnaei is a freshwater macroalga that is generally regarded as a rare species. It is apparently absent from large but seemingly suitable areas of the Northern Hemisphere, implying a limited dispersal potential and an imprint of Pleistocene glaciations in its biogeography. However, despite the popularity of its enigmatic lake ball‐form, detailed biogeographical studies of A. linnaei have never been conducted. The main means of reproduction of A. linnaei is fragmentation and akinetes are not formed, supporting the assumption of limited dispersal capacity. The aim of this study was to reconstruct the biogeography of A. linnaei, and to identify possible refugia during glaciations, as well as to evaluate dispersal potential by quantitative desiccation experiments. Location Palaearctic. Methods The current distribution of A. linnaei was inferred from herbarium specimens, literature data and recent field observations. All herbarium specimens were morphologically re‐examined. Desiccation experiments were performed with vegetative filaments of three isolates of A. linnaei, as no specialized resistant stages are known. For comparison, the widespread freshwater algae Cladophora glomerata and Rhizoclonium sp. were included. Internal transcribed spacer (ITS) ribosomal DNA sequences were generated and a ribotype network was constructed. Results Aegagropila linnaei was recorded from 283 locations in freshwater and brackish environments. The majority of locations were in central and northern Europe in previously glaciated areas. Desiccation experiments showed that A. linnaei is very susceptible to desiccation. Based on ITS sequences of 34 samples, five different ribotypes were identified. Four of these ribotypes had a restricted distribution. Aegagropila linnaei represents a single species with little genetic variation (0.1–0.5%). Main conclusions This is the most comprehensive study of this species so far, reporting many new locations and tackling several taxonomic problems. Few additional finds were made from North America, and the origin of A. linnaei is inferred to be in Asia. The highest density of its present‐day locations is in previously glaciated areas in Europe, where glacial ice‐dammed lakes might have functioned as refugia. Low effective long‐distance dispersal capacity is inferred, based on high susceptibility to desiccation and its modes of dispersal. 相似文献
183.
184.
Diacylglycerol kinase (DGK) is suggested to attenuate diacylglycerol-induced cell responses through the phosphorylation of this second messenger to phosphatidic acid. Here, we show that DGKalpha, an isoform highly expressed in T lymphocytes, translocates from cytosol to the plasma membrane in response to two different receptors known to elicit T cell activation responses: an ectopically expressed muscarinic type I receptor and the endogenous T cell receptor. Translocation in response to receptor stimulation is rapid, transient, and requires calcium and tyrosine kinase activation. DGKalpha-mediated phosphatidic acid generation allows dissociation of the enzyme from the plasma membrane and return to the cytosol, as demonstrated using a pharmacological inhibitor and a catalytically inactive version of the enzyme. The NH(2)-terminal domain of the protein is shown to be responsible for receptor-induced translocation and phosphatidic acid-mediated membrane dissociation. After examining induction of the T cell activation marker CD69 in cells expressing a constitutively active form of the enzyme, we present evidence of the negative regulation that DGKalpha exerts on diacylglycerol-derived cell responses. This study is the first to describe DGKalpha as an integral component of the signaling cascades that link plasma membrane receptors to nuclear responses. 相似文献
185.
Ottenschläger I Barinova I Voronin V Dahl M Heberle-Bors E Touraev A 《Transgenic research》1999,8(4):279-294
The transient expression of three mutant forms of green fluorescent protein (GFP) genes, GFP4, GFP5ER, and GFP4S65C, under several constitutive and pollenspecific promoters throughout pollen development in Nicotianatabacum, thaliana and Antirrhinummajus is described. Immature pollen of tobacco, Arabidopsis and snapdragon, isolated at different developmental stages, were bombarded with plasmids containing the GFP and cultured in vitro for several days until maturity. The expression of GFP was monitored every day during in vitro maturation, germination and pollination, as well as after in situ pollination. The expression pattern of each construct was compared in parallel experiments to that of ßglucuronidase (GUS) constructs expressed by the same promoters. The results show that the expression level of all three GFP mutant forms was dependent on the strength of the promoter used. The strongest promoter was the DC3 promoter, and no notable differences in the intensity and brightness of all three versions of GFP were observed. GFPexpressing pollen from tobacco and snapdragon developed in vitro for several days until maturity and germinated in vitro as well as on the surface of stigmata, strongly suggesting that all three GFPs are not toxic for the development of functional pollen. Furthermore, stably transformed tobacco plants expressing GFP under the control of the strong pollenexpressed DC3 and LAT52 promoters were not impaired in reproductive function, confirming that GFP can be used as a nondestructive marker for plant reproductive biology and development. 相似文献
186.
Remans Tony Schenk Peer M. Manners John M. Grof Christopher P.L. Elliott Adrian R. 《Plant Molecular Biology Reporter》1999,17(4):385-395
The Green Fluorescent Protein (GFP) from Aequorea victoria has begun to be used as a reporter protein in plants. It is particularly useful as GFP fluorescence can be detected in a non-destructive manner, whereas detection of enzyme-based reporters often requires destruction of the plant tissue. The use of GFP as a reporter enables transgenic plant tissues to be screened in vivo at any growth stage. Quantification of GFP in transgenic plant extracts will increase the utility of GFP as a reporter protein. We report herein the quantification of a mGFP5-ER variant in tobacco leaf extracts by UV excitation and a sGFP(S65T) variant in sugarcane leaf and callus extracts by blue light excitation using the BioRad VersaFluorTM Fluorometer System or the Labsystems Fluoroskan Ascent FL equipped with a narrow band emission filter (510 ± 5 nm). The GFP concentration in transgenic plant extracts was determined from a GFP-standard series prepared in untransformed plant extract with concentrations ranging from 0.1 to 4 g/ml of purified rGFP. Levels of sgfp(S65T) expression, driven by the maize ubiquitin promoter, in sugarcane calli and leaves ranged up to 0.525 g and 2.11 g sGFP(S65T) per mg of extractable protein respectively. In tobacco leaves the expression of mgfp5-ER, driven by the cauliflower mosaic virus (CaMV) 35S promoter, ranged up to 7.05 g mGFP5-ER per mg extractable protein. 相似文献
187.
Rafael Zárate Johan Memelink Robert van der Heijden Robert Verpoorte 《Biotechnology letters》1999,21(11):997-1002
In vitro propagation of Catharanthus roseus was achieved using nodal explants. Bud induction was best on medium containing 1.0 mg benzyl aminopurine l–1. Hardening of rooted shoots to soil was very successful with 98% survival. Genetically transformed C. roseus plantlets were obtained after bombardment of nodal explants, which were then micropropagated, with DNA coated particles with green fluorescent protein (GFP) or -glucuronidase (GUS) reporter genes. Histological studies showed that the gene insertion method proved effective with many cells and different tissues displaying the reporter gene signals, showing that gene expressions were rather stable. 相似文献
188.
Effects of the C132-methoxycarbonyl moiety on the self-assembly of chlorosomal chlorophylls (Chls) were studied. Model compounds, zinc methyl 3-devinyl-3-(1-hydroxymethyl)-pheophorbides a and a (Zn-31-OH-Chls a/a, C132-epimers) were synthesized from Chl a, and their aggregation behaviors were examined in Triton X-100 (TX-100) micellar suspensions and in 6%THF/water, in comparison with those of a pyrolized derivative, zinc methyl 3-devinyl-3-(1-hydroxymethyl)-132-demethoxycarbonyl-pheophorbide a (Zn-31-OH-pyroChl a). Zn-31-OH-Chl a formed self-aggregates in the TX-100 micellar suspension and gave a Qy absorption peak at 703 nm, while Zn-31-OH-pyroChl a aggregates of a Qy peak at 740 nm. In the Zn-31-OH-Chl a aggregate spectrum, the Qy red-shift was smaller, the band shape was broader, and the contribution of the residual monomer was more intense than that in the Zn-31-OH-pyroChl a aggregate spectrum. The bulky C132-moiety limits the ways of molecular association, and electronic interaction between the component molecules of the Zn-31-OH-Chl a aggregate is weakened. Stereoselective control of the aggregation of the C132-epimer was also examined. 相似文献
189.
190.
Electrokinetic chromatography was employed to separate the enantiomers of two novel functionalized ruthenium(II) complexes with different polypyridyl coordination spheres. The use of anionic carboxymethyl-beta-cyclodextrin as chiral mobile phase additive resulted in maximum efficiency and resolution for the enantiomer separation of both transition metal complexes. The syntheses of the [4-(3-hydroxypropyl)-4'-methyl-2,2'-bipyridine]-bis(2,2'-bipyridine)rethenium(II)-bis(tetrafluoroborate) and [4-(3-hydroxypropyl)-4'-methyl-2,2'-bipyridine]-bis(4,4'-dimethyl-2,2'-bypyridine)ruthenium(II)-bis(tetrafluoroborate) complexes and their complete characterization by means of two-dimensional (1)H and (13)C[(1)H] NMR techniques ((1)H-(1)H COSY and (1)H-(13)C HMQC) as well as elemental analyses and MALDI-TOFMS are described in detail. The functionalized complexes can be used as building blocks for further reactions with polymers, biopolymers, surfaces and nanoparticles. 相似文献