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171.
Cytoskeletal proteins in adherens-type cell-matrix junctions. 总被引:1,自引:0,他引:1
D R Critchley A Gilmore L Hemmings P Jackson A McGregor V Ohanian B Patel G Waites C Wood 《Biochemical Society transactions》1991,19(4):1028-1033
172.
Zikmundová M Drandarov K Hesse M Werner C 《Zeitschrift für Naturforschung. C, Journal of biosciences》2002,57(7-8):660-665
The biotransformation of the phytoanticipin HBOA and its major degradation metabolites 2-hydroxy-N-(2-hydroxyphenyl)acetamide (7) and N-(2-hydroxyphenyl)acetamide (8) by Chaetosphaeria sp., an endophytic fungus isolated from Aphelandra tetragona, was studied. Three new metabolites could be identified as 2-amino-7-hydroxy-3H-phenoxazin-3-one (12), 2-acetylamino-7-hydroxy-3H-phenoxazin-3-one (13) and 7-hydroxy-2-(2-hydroxyacetyl)-amino-3H-phenoxazin-3-one (14). Structure elucidation of 12 and 13 was performed by MS, 1H, 13C NMR and 2D NMR techniques and confirmed by chemical transformation. 相似文献
173.
Steven J. Cooke Christa M. Woodley M. Brad Eppard Richard S. Brown Jennifer L. Nielsen 《Reviews in Fish Biology and Fisheries》2011,21(1):127-151
Early approaches to surgical implantation of electronic tags in fish were often through trial and error, however, in recent
years there has been an interest in using scientific research to identify techniques and procedures that improve the outcome
of surgical procedures and determine the effects of tagging on individuals. Here we summarize the trends in 108 peer-reviewed
electronic tagging effect studies focused on intracoleomic implantation to determine opportunities for future research. To
date, almost all of the studies have been conducted in freshwater, typically in laboratory environments, and have focused
on biotelemetry devices. The majority of studies have focused on salmonids, cyprinids, ictalurids and centrarchids, with a
regional bias towards North America, Europe and Australia. Most studies have focused on determining whether there is a negative
effect of tagging relative to control fish, with proportionally fewer that have contrasted different aspects of the surgical
procedure (e.g., methods of sterilization, incision location, wound closure material) that could advance the discipline. Many
of these studies included routine endpoints such as mortality, growth, healing and tag retention, with fewer addressing sublethal
measures such as swimming ability, predator avoidance, physiological costs, or fitness. Continued research is needed to further
elevate the practice of electronic tag implantation in fish in order to ensure that the data generated are relevant to untagged
conspecifics (i.e., no long-term behavioural or physiological consequences) and the surgical procedure does not impair the
health and welfare status of the tagged fish. To that end, we advocate for (1) rigorous controlled manipulations based on
statistical designs that have adequate power, account for inter-individual variation, and include controls and shams, (2)
studies that transcend the laboratory and the field with more studies in marine waters, (3) incorporation of knowledge and
techniques emerging from the medical and veterinary disciplines, (4) addressing all components of the surgical event, (5)
comparative studies that evaluate the same surgical techniques on multiple species and in different environments, (6) consideration
of how biotic factors (e.g., sex, age, size) influence tagging outcomes, and (7) studies that cover a range of endpoints over
ecologically relevant time periods. 相似文献
174.
Jianjun Dai Shaohui Wang Doreen Guerlebeck Claudia Laturnus Sebastian Guenther Zhenyu Shi Chengping Lu Christa Ewers 《BMC microbiology》2010,10(1):236
Background
Extraintestinal pathogenic E. coli (ExPEC) represent a phylogenetically diverse group of bacteria which are implicated in a large range of infections in humans and animals. Although subgroups of different ExPEC pathotypes, including uropathogenic, newborn meningitis causing, and avian pathogenic E. coli (APEC) share a number of virulence features, there still might be factors specifically contributing to the pathogenesis of a certain subset of strains or a distinct pathotype. Thus, we made use of suppression subtractive hybridization and compared APEC strain IMT5155 (O2:K1:H5; sequence type complex 95) with human uropathogenic E. coli strain CFT073 (O6:K2:H5; sequence type complex 73) to identify factors which may complete the currently existing model of APEC pathogenicity and further elucidate the position of this avian pathoype within the whole ExPEC group. 相似文献175.
Wajahatullah Khan David Hiltz Alan T. Critchley Balakrishnan Prithiviraj 《Journal of applied phycology》2011,23(3):409-414
Ascophyllum nodosum, a brown macroalga, is the most widely used seaweed in agriculture. We report a rapid method for the detection of cytokinin-like activity in plants treated with a commercial A. nodosum liquid concentrate (Stimplex®) using a transgenic line of Arabidopsis carrying the ARR5 promoter fused to ß-glucuronidase (GUS) reporter gene. Based on GUS activity assay, an increase in cytokinin-like activity was detected in plants grown in vitro treated with 3 mL L?1 Stimplex®, whereas foliar spray treatments showed similar cytokinin-like activity at a concentration of 5 mL L?1. Histochemical staining showed Stimplex®-induced GUS activity in leaf as well as in the root tissues. Taken together, our results suggest that Stimplex® contains compounds that may elicit endogenous cytokinin-like activity. Furthermore, it is shown that this bioassay can be used for rapid screening of extracts that can stimulate cytokinin-like activities using Arabidopsis AAR5::GUS reporter transgenic plants. 相似文献
176.
Summary A model predicting net photosynthesis of individual plant leaves for a variety of environmental conditions has been developed. It is based on an electrical analogue describing gas diffusion from the free atmosphere to the sites of CO2 fixation and a Michaelis-Menten equation describing CO2 fixation. The model is presented in two versions, a simplified form without respiration and a more complex form including respiration. Both versions include terms for light and temperature dependence of CO2 fixation and light control of stomatal resistance. The second version also includes terms for temperature, light, and oxygen dependence of respiration and O2 dependence of CO2 fixation.The model is illustrated with curves based on representative values of the various environmental and biological parameters. These curves relate net photosynthesis to light intensity, [CO2], [O2], temperature, and resistances to CO2 uptake. The shape of the [CO2]-net photosynthesis curves depends on the total diffusion resistance to CO2 uptake and the Michaelis constant for CO2 uptake. The curves range from typical Michaelis-Menten to Blackman types.The model is combined with a model of leaf energy exchange permitting simultaneous estimation of net photosynthesis and transpiration. The combined model is illustrated with curves relating transpiration to photosynthesis under a wide variety of environmental conditions. Environmental regimes yielding maximum efficiency of water use are identified for the given assumptions and biological parameters. 相似文献
177.
Sicking C Brusch M Lindackers A Riedel KU Schubert B Isakovic N Krall C Klipp W Drepper T Schneider K Masepohl B 《Journal of bacteriology》2005,187(1):92-98
Growth of Rhodobacter capsulatus with molecular dinitrogen as the sole N source via the alternative Fe-only nitrogenase requires all seven gene products of the anfHDGK-1-2-3 operon. In contrast to mutant strains carrying lesions in the structural genes of nitrogenase (anfH, anfD, anfG, and anfK), strains defective for either anf1, anf2, or anf3 are still able to reduce the artificial substrate acetylene, although with diminished activity. To obtain further information on the role of Anf1, we screened an R. capsulatus genomic library designed for use in yeast two-hybrid studies with Anf1 as bait. Two genes, which we propose to call ranR and ranT (for genes related to alternative nitrogenase), coding for products that interact with Anf1 were identified. A ranR mutant exhibited a phenotype similar to that of an anf1 mutant strain (no growth with N2 in the absence of molybdenum, but significant reduction of acetylene via the Fe-only nitrogenase), whereas a ranT mutant retained the ability to grow diazotrophically, but growth was clearly delayed compared to the parental strain. In contrast to the situation for anf1, expression of neither ranR nor ranT was regulated by ammonium or molybdenum. A putative role for Anf1, RanR, and RanT in the acquisition and/or processing of iron in connection with the Fe-only nitrogenase system is discussed. 相似文献
178.
179.
Gerald Sendlhofer David Benjamin Lumenta Karina Leitgeb Brigitte Kober Lydia Jantscher Monika Schanbacher Andrea Berghold Gudrun Pregartner Gernot Brunner Christa Tax Lars Peter Kamolz 《PloS one》2016,11(2)
Background
“The Surgical Safety Checklist (SSC) is important, but we don’t use it adequately” is a well-suited statement that reflects the SSC''s application in hospitals. Our aim was to follow up on our initial study on compliance (2014) by analysing differences between individual perception and compliance with the SSC.Methods
We conducted a follow-up online survey to assess healthcare professionals’ individual perception of, as well as satisfaction and compliance with the SSC three years following its thorough implementation.Results
171 (19.5%) of 875 operating team members completed the online survey. 99.4% confirmed using the SSC. Self-estimated subjective knowledge about the intention of the checklist was high, whereas objective knowledge was moderate, but improved as compared to 2014. According to an independent audit the SSC was used in 93.1% of all operations and among the SSCs used the completion rate was 57.2%. The use of the SSC was rated as rather easy [median (IQR): 7 (6–7)], familiar [7 (6–7)], generally important [7 (7–7)], and good for patients [7 (6–7)] as well as for employees [7 (7–7)]. Only comfort of use was rated lower [6 (5–7)].Conclusion
There is a gap between individual perception and actual application of the SSC. Despite healthcare professionals confirming the importance of the SSC, compliance was moderate. The introduction of SSCs in the health care sector remains a constant challenge and requires continuous re-evaluation as well as a sensible integration into existing workflows in hospitals. 相似文献180.
Detection of genetic variants affecting cattle behaviour and their impact on milk production: a genome‐wide association study 下载免费PDF全文
Juliane Friedrich Bodo Brand Siriluck Ponsuksili Katharina L. Graunke Jan Langbein Jacqueline Knaust Christa Kühn Manfred Schwerin 《Animal genetics》2016,47(1):12-18
Behaviour traits of cattle have been reported to affect important production traits, such as meat quality and milk performance as well as reproduction and health. Genetic predisposition is, together with environmental stimuli, undoubtedly involved in the development of behaviour phenotypes. Underlying molecular mechanisms affecting behaviour in general and behaviour and productions traits in particular still have to be studied in detail. Therefore, we performed a genome‐wide association study in an F2 Charolais × German Holstein cross‐breed population to identify genetic variants that affect behaviour‐related traits assessed in an open‐field and novel‐object test and analysed their putative impact on milk performance. Of 37 201 tested single nucleotide polymorphism (SNPs), four showed a genome‐wide and 37 a chromosome‐wide significant association with behaviour traits assessed in both tests. Nine of the SNPs that were associated with behaviour traits likewise showed a nominal significant association with milk performance traits. On chromosomes 14 and 29, six SNPs were identified to be associated with exploratory behaviour and inactivity during the novel‐object test as well as with milk yield traits. Least squares means for behaviour and milk performance traits for these SNPs revealed that genotypes associated with higher inactivity and less exploratory behaviour promote higher milk yields. Whether these results are due to molecular mechanisms simultaneously affecting behaviour and milk performance or due to a behaviour predisposition, which causes indirect effects on milk performance by influencing individual reactivity, needs further investigation. 相似文献