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91.
Objective: The aim of the present study was to evaluate the impact of dry mouth conditions on oral health‐related quality of life in frail old people, residents at community care centers. Further, reliability and validity of a visual analogue scale (VAS) for dry mouth symptoms were determined within the study cohort. Background: In old people functional, social and psychological impacts of oral conditions are associated with an overall sense of well being and general health. Subjective dry mouth and reduced saliva flow are common disorders in old people caused by disease and medication. Thus, dry mouth conditions may be determinants for compromised oral health‐related quality of life in old people. Method: In total, 50 old people living at service homes for the old people were asked to answer questionnaires on subjective dry mouth (VAS) and Oral Health Impact Profile (OHIP14) for oral health‐related quality of life. Saliva flow was estimated by absorbing saliva into a pre‐weighed cotton roll. Results: The final study cohort comprised 41 old people (aged 83–91 years). Significant associations were identified between both objective and subjective dry mouth and overall or specific aspects of oral health‐related quality of life. Conclusion: Dry mouth (objective and subjective) is significantly associated with oral health‐related quality of life strengthening the value of monitoring dry mouth conditions in the care of frail old people. 相似文献
92.
Algesten G Sobek S Bergström AK Jonsson A Tranvik LJ Jansson M 《Microbial ecology》2005,50(4):529-535
We measured sediment production of carbon dioxide (CO2) and methane (CH4) and the net flux of CO2 across the surfaces of 15 boreal and subarctic lakes of different humic contents. Sediment respiration measurements were
made in situ under ambient light conditions. The flux of CO2 between sediment and water varied between an uptake of 53 and an efflux of 182 mg C m−2 day−1 from the sediments. The mean respiration rate for sediments in contact with the upper mixed layer (SedR) was positively correlated
to dissolved organic carbon (DOC) concentration in the water (r2 = 0.61). The net flux of CO2 across the lake surface [net ecosystem exchange (NEE)] was also closely correlated to DOC concentration in the upper mixed
layer (r2 = 0.73). The respiration in the water column was generally 10-fold higher per unit lake area compared to sediment respiration.
Lakes with DOC concentrations <5.6 mg L−1 had net consumption of CO2 in the sediments, which we ascribe to benthic primary production. Only lakes with very low DOC concentrations were net autotrophic
(<2.6 mg L−1) due to the dominance of dissolved allochthonous organic carbon in the water as an energy source for aquatic organisms. In
addition to previous findings of allochthonous organic matter as an important driver of heterotrophic metabolism in the water
column of lakes, this study suggests that sediment metabolism is also highly dependent on allochthonous carbon sources. 相似文献
93.
We disclose an efficient procedure for the preparation of ethers of 2-substituted 2-hydroxymethylpyrroline and of 2-aminomethyl-3-pyrrolines, involving, as a key step, formation and nucleophilic ring opening of a cyclic sulfamidate. Several new analogs of epibatidine (1) and tebanicline (ABT-594, 2) were prepared and tested for analgesic activity in the mouse formalin model. 相似文献
94.
AB Chang NC Cox J Purcell JM Marchant PJ Lewindon GJ Cleghorn LC Ee GD Withers MK Patrick J Faoagali 《Respiratory research》2005,6(1):1-5
Background and methods
Human metapneumovirus (hMPV) is a recently discovered respiratory virus associated with bronchiolitis, pneumonia, croup and exacerbations of asthma. Since respiratory viruses are frequently detected in patients with acute exacerbations of COPD (AE-COPD) it was our aim to investigate the frequency of hMPV detection in a prospective cohort of hospitalized patients with AE-COPD compared to patients with stable COPD and to smokers without by means of quantitative real-time RT-PCR.Results
We analysed nasal lavage and induced sputum of 130 patients with AE-COPD, 65 patients with stable COPD and 34 smokers without COPD. HMPV was detected in 3/130 (2.3%) AE-COPD patients with a mean of 6.5 × 105 viral copies/ml in nasal lavage and 1.88 × 105 viral copies/ml in induced sputum. It was not found in patients with stable COPD or smokers without COPD.Conclusion
HMPV is only found in a very small number of patients with AE-COPD. However it should be considered as a further possible viral trigger of AE-COPD because asymptomatic carriage is unlikely. 相似文献95.
CD21/CD19 coreceptor signaling promotes B cell survival during primary immune responses 总被引:2,自引:0,他引:2
Barrington RA Zhang M Zhong X Jonsson H Holodick N Cherukuri A Pierce SK Rothstein TL Carroll MC 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(5):2859-2867
The adaptive immune response is tightly regulated to limit responding cells in an Ag-specific manner. On B cells, coreceptors CD21/CD19 modulate the strength of BCR signals, potentially influencing cell fate. The importance of the CD95 pathway was examined in response of B cells to moderate affinity Ag using an adoptive transfer model of lysozyme-specific Ig transgenic (HEL immunoglobulin transgene (MD4) strain) B cells. Although adoptively transferred Cr2+/+ MD4 B cells are activated and persist within splenic follicles of duck egg lysozyme-immunized mice, Cr2-/- MD4 B cells do not. In contrast, Cr2-/- MD4 lpr B cells persist after transfer, suggesting that lack of CD21/CD35 signaling results in CD95-mediated elimination. Cr2 deficiency did not affect CD95 levels, but cellular FLIP (c-FLIP) protein and mRNA levels were reduced 2-fold compared with levels in Cr2+/+ MD4 B cells. In vitro culture with Cr2+/+ MD4 B cells demonstrated that equimolar amounts of rHEL-C3d3 were more effective than hen egg lysozyme alone in up-regulating c-FLIP levels and for protection against CD95-mediated apoptosis. Collectively, this study implies a mechanism for regulating B cell survival in vivo whereby the strength of BCR signaling (including coreceptor) determines c-FLIP levels and protection from CD95-induced death. 相似文献
96.
Pär Jonsson Hans Stenlund Thomas Moritz Johan Trygg Michael Sjöström Elwin R. Verheij Johan Lindberg Ina Schuppe-Koistinen Henrik Antti 《Metabolomics : Official journal of the Metabolomic Society》2006,2(3):135-143
A multivariate strategy for studying the metabolic response over time in urinary GC/MS data is presented and exemplified by a study of drug-induced liver toxicity in the rat. The strategy includes the generation of representative data through hierarchical multivariate curve resolution (H-MCR), highlighting the importance of obtaining resolved metabolite profiles for quantification and identification of exogenous (drug related) and endogenous compounds (potential biomarkers) and for allowing reliable comparisons of multiple samples through multivariate projections. Batch modelling was used to monitor and characterize the normal (control) metabolic variation over time as well as to map the dynamic response of the drug treated animals in relation to the control. In this way treatment related metabolic responses over time could be detected and classified as being drug related or being potential biomarkers. In summary the proposed strategy uses the relatively high sensitivity and reproducibility of GC/MS in combination with efficient multivariate curve resolution and data analysis to discover individual markers of drug metabolism and drug toxicity. The presented results imply that the strategy can be of great value in drug toxicity studies for classifying metabolic markers in relation to their dynamic responses as well as for biomarker identification. 相似文献
97.
Dondero F Jonsson H Rebelo M Pesce G Berti E Pons G Viarengo A 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2006,143(2):150-157
Amoebic Dictyostelium discoideum cells were employed in a bioassay to evaluate stress responses after exposures to the polyaromatic hydrocarbon benzo[a]pyrene (B[a]P) and two heavy metals (copper and mercury). Furthermore, we developed a recombinant cell line expressing a labile Green Fluorescent Protein (GFP) variant expressed under the control of an actin promoter to monitor stress-related protein degradation. Finally, cell viability was monitored to discriminate lethal exposure concentrations. The results demonstrated that exposure to sub-micromolar concentrations of mercury rendered significant changes in all studied physiological parameters, whereas B[a]P became toxic at low micromolar, and copper at high micromolar concentrations. Exposure to 0.5 microM mercury significantly reduced lysosomal membrane stability (LMS), endocytosis rate, GFP expression, and further resulted in the elevation of cytosolic free Ca(2+) ([Ca(2+)](i)). LMS in mercury-treated cells that had been pre-incubated with a specific Ca(2+)-dependent phospholipase A2 blocking agent was however not affected by the exposure, indicating that the toxic action of mercury is linked to the activation of phospholipase A2 via a Ca(2+)-signaling pathway. Exposure to 20 microM B[a]P significantly reduced LMS, endocytosis rate, and GFP expression, however without affecting [Ca(2+)](i), suggesting a calcium-independent route of toxicity for this compound. None of the physiological parameters were significantly affected by copper exposure at concentrations <400 microM, demonstrating a high resistance to this metal. Our results further showed that neither cell growth nor viability was affected by concentrations altering the studied physiological parameters. LMS, endocytosis rate, and [Ca(2+)](I), therefore, appear sensitive biomarkers of pollutant-related stress in amoebic cells. 相似文献
98.
The presence of copper in water environment may have detrimental effects on aquatic organisms, including algae, where different
enzymatic systems can be affected. Algae acid phosphatase plays important roles in metabolic processes such as decomposition
of organic phosphate, autophagic digestive process, recycling cellular materials and zygote formation during reproduction.
This work describes an in vitro activation effect of copper on the acid phosphatase of the green algae Pseudokirchneriella subcapitata (formely Selenastrum capricornutum) under preincubation condition. Apparent Michaelis constant values of 1.21 and 0.37 mM, and activation energy values of 26.8
and 13.6 kJ mol−1 were determined in the absence and in the presence of 0.2 mM Cu2+, respectively. The dissociation constant value for Cu2+ binding to the enzyme was determined to be 22.04 μM. The decrease of the apparent Michaelis constant (Km) and activation
energy values in the presence of Cu2+ correlates well with its activating effect on the acid phosphatase activity. This propriety could be used as a sensitive
bioindicator for copper in environmental samples. 相似文献
99.
N.N. Jonsson C. Cutullè S.W. Corley J.M. Seddon 《International journal for parasitology》2010,40(14):1659-1664
A mutation in the domain II S4–5 linker region of the para-sodium channel gene has been associated previously with synthetic pyrethroid (SP) resistance in the cattle tick (Rhipicephalus microplus) in Australia. This is a C → A mutation at nucleotide position 190, which results in a leucine to isoleucine amino acid substitution (L64I). In a survey of 15 cattle tick populations with known SP resistance status, sourced from Queensland and New South Wales in Australia, there was a strong relationship (r = 0.98) between the proportion of ticks carrying the L64I homozygous resistant genotype and the survival percentage after exposure to a discriminating concentration of cypermethrin in the bioassay, as expected. However, among populations resistant only to flumethrin, the L64I homozygous genotype was not found. The sequence obtained for a 167 bp region including domain II S4–5 linker in flumethrin-resistant ticks identified a G → T non-synonymous mutation at nucleotide position 214 that results in a glycine to valine substitution (G72V). The frequency of the G72V homozygous genotype in each population was found to be moderately related to the survival percentage at the discriminating concentration of flumethrin in the larval packet test (r = 0.74). However, a much stronger relationship between genotype and resistance to flumethrin was observed when the heterozygotes of L64I and G72V were added to the G72V homozygotes (r = 0.93). These results suggest that there is an interaction between the two mutations in the same gene, such that flumethrin resistance might be conferred by either two copies of the G72V mutation or by being a L64I and G72V heterozygote. 相似文献
100.
Making water flow: a comparison of the hydrodynamic characteristics of 12 different benthic biological flumes 总被引:1,自引:0,他引:1
Per R. Jonsson Luca A. van Duren Muriel Amielh Ragnhild Asmus Rebecca J. Aspden Darius Daunys Michael Friedrichs Patrick L. Friend Frédéric Olivier Nick Pope Elimar Precht Pierre-Guy Sauriau Estelle Schaaff 《Aquatic Ecology》2006,40(4):409-438
Flume tanks are becoming increasingly important research tools in aquatic ecology, to link biological to hydrodynamical processes. There is no such thing as a “standard flume tank”, and no flume tank is suitable for every type of research question. A series of experiments has been carried out to characterise and compare the hydrodynamic characteristics of 12 different flume tanks that are designed specifically for biological research. These facilities are part of the EU network BioFlow. The flumes could be divided into four basic design types: straight, racetrack, annular and field flumes. In each facility, two vertical velocity profiles were measured: one at 0.05 m s−1 and one at 0.25 m s−1. In those flumes equipped with Acoustic Doppler Velocimeters (ADV), time series were also recorded for each velocity at two heights above the bottom: 0.05 m and 20% of the water depth. From these measurements turbulence characteristics, such as TKE and Reynolds stress, were derived, and autocorrelation spectra of the horizontal along-stream velocity component were plotted. The flume measurements were compared to two sets of velocity profiles measured in the field.Despite the fact that some flumes were relatively small, turbulence was fully developed in all channels. Straight and racetrack flumes generally produced boundary layers with a clearly definable logarithmic layer, similar to measurements in the field taken under steady flow conditions. The two annular flumes produced relatively thin boundary layers, presumably due to secondary flows developing in the curved channels. The profiles in the field flumes also differed considerably from the expected log profile. This may either have been due the construction of the flume, or due to unsteady conditions during measurement. Constraints imposed by the different flume designs on the suitability for different types of boundary layer research, as well as scaling issues are discussed. 相似文献