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951.
There is growing support for the general notion that the drivers of invasion success often shift from biotic to abiotic factors
with increasing spatial scale. Most of this research, however, has been conducted on a single trophic level; i.e. it has primarily
looked at how the diversity of native competitors may influence invasion success. Less attention has been paid to understanding
how native prey diversity may influence the invasion success of exotic predators and whether such biotic factors are scale-dependent.
We used a hierarchical spatial survey of 17 stream communities to test whether native prey diversity, along with native prey
biomass, algal resource abundance and annual stream discharge, influenced the abundance of an exotic crayfish predator, and
whether the importance of these factors were scale-dependent. We used a hierarchical generalized linear model to evaluate
the influence of these community and stream characteristics on exotic crayfish abundance at both the transect scale (1 m2) and the stream scale (400 m2). Our results indicated that at the stream scale, high stream discharge significantly limited invader abundance. However,
at the smaller transect scale, native prey biomass was a significant driver of invasion success and positively correlated
with invader abundance. We suggest that our results add to the emerging pattern that abiotic processes are stronger determinants
of invasion success at large spatial scales, whereas biotic processes become more important with decreasing spatial scale.
However, for predator invasions, prey biomass, not prey diversity may be a more important for driver of invasion success at
small spatial scales. 相似文献
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953.
Halil Erhan Eroğlu Ahmet Aksoy Ergin Hamzaoğlu Ümit Budak Sevil Albayrak 《Cytotechnology》2009,59(1):65-72
Helichrysum Mill. (Asteraceae) species have been used in folk medicine for thousands of years in the world. The in vitro cytogenetic
effects in human lymphocytes of nine Helichrysum taxa used in Turkey folk medicine were investigated. Blood samples were obtained from healthy donors, non-smoking volunteers,
which were incubated and exposed to increasing concentrations of methanol extracts of Helichrysum taxa (0.01, 0.05, 0.1, 0.5 and 1 mg/mL). The inhibitory effects of H. stoechas (L.) Moench subsp. barrelieri (Ten.) Nyman, H. armenium DC. subsp. armenium, H. armenium DC. subsp. araxinum (Kirp.) Takht., H. plicatum DC. subsp. plicatum, H. compactum Boiss. and H. artvinense P.H.Davis & Kupicha on the mitotic index and replication index indicate that these taxa can have genotoxic and mutagenic
effects. They should therefore not be used freely in alternative medicine although their antiproliferative activity may suggest
anticarcinogenic properties. Increase effects of H. stoechas subsp. barrelieri, H. armenium subsp. armenium, H. armenium subsp. araxinum, H. chasmolycicum P.H.Davis, H. plicatum subsp. plicatum, H. compactum and H. artvinense on the micronucleus rates showed that these taxa can have genotoxic and carcinogenic effects. 相似文献
954.
Katrina Laks Tiina Kirsipuu Tuuli Dmitrijeva Andres Salumets Peep Palumaa 《The protein journal》2016,35(3):171-176
Biological fluid sample collection often includes the risk of blood contamination that may alter the proteomic profile of biological fluid. In proteomics studies, exclusion of contaminated samples is usually based on visual inspection and counting of red blood cells in the sample; analysis of specific blood derived proteins is less used. To fill the gap, we developed a fast and sensitive method for ascertainment of blood contamination in crude biological fluids, based on specific blood-derived protein, hemoglobin detection by MALDI-TOF MS. The MALDI-TOF MS based method allows detection of trace hemoglobin with the detection limit of 0.12 nM. UV-spectrometry, which was used as reference method, was found to be less sensitive. The main advantages of the presented method are that it is fast, effective, sensitive, requires very small sample amount and can be applied for detection of blood contamination in various biological fluids collected for proteomics studies. Method applicability was tested on human cerebrospinal and follicular fluid, which proteomes generally do not contain hemoglobin, however, which possess high risk for blood contamination. Present method successfully detected the blood contamination in 12 % of cerebrospinal fluid and 24 % of follicular fluid samples. High percentage of contaminated samples accentuates the need for initial inspection of proteomic samples to avoid incorrect results from blood proteome overlap. 相似文献
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Phage display, one of today’s fundamental drug discovery technologies, allows identification of a broad range of biological drugs, including peptides, antibodies and other proteins, with the ability to tailor critical characteristics such as potency, specificity and cross-species binding. Further, unlike in vivo technologies, generating phage display-derived antibodies is not restricted by immunological tolerance. Although more than 20 phage display-derived antibody and peptides are currently in late-stage clinical trials or approved, there is little literature addressing the specific challenges and successes in the clinical development of phage-derived drugs. This review uses case studies, from candidate identification through clinical development, to illustrate the utility of phage display as a drug discovery tool, and offers a perspective for future developments of phage display technology. 相似文献
958.
In vitro hybridization of seven pairs of genetically different murine cell has been demonstrated by the use of karyological markers, and pure cultures of these hybrids have been isolated. All somatic hybrids showed a progressive loss of chromosomes during this proliferation in vitro. 相似文献
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960.