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991.
Tripathi MK Mishra AS Misra AK Vaithiyanathan S Prasad R Jakhmola RC 《Letters in applied microbiology》2008,46(3):364-370
Aims: Selection of white‐rot fungi of bio‐conversion of mustard straw (MS) into feed for ruminants. Methods and Results: Mustard straw was cultured with Ganoderma applanatum, Coriolus versicolor and Phanerochaete chrysosporium for solid‐state fermentation at 35°C from 7 to 63 days for dilignification and for 21 days to study dry matter digestibility and protein enrichment. Lignin loss in fungus cultured straw varied between 100 and 470 g kg?1 lignin. Dilignification was higher between 7 and 28 days fermentation with C. versicolor. Among the three fungi P. chrysosporium was the most effective in degrading lignin for longer fermentation. In‐vitro dry matter digestibility (IVDMD) and crude protein content was higher in C. versicolor cultured straw. Large quantity of straw was cultured by C. versicolor for 21 days, for in vivo evaluation. Mean pH and metabolites of rumen fermentation were not different while, pH and volatile fatty acid increased at 6 h postfermentation on cultured straw feeding. Cultured straw fermentation increased (P = 0·001) small holotricks and reduced (P = 0·005) large holotricks population. Fungus cultures straw did not improve microbial enzyme concentration. Conclusions: Coriolus versicolor and P. chrysosporium were the promising fungus for MS bio‐dilignification. Significance and Impact of the Study: Coriolus versicolor treated MS improved dry matter digestibility and protein content. 相似文献
992.
AIMS: To monitor in real-time the changes in microbial populations and chemistry of grape juice simultaneously inoculated with Saccharomyces cerevisiae and Oenococcus oeni. METHODS AND RESULTS: Viable populations of S. cerevisiae and O. oeni in Chardonnay fermentations were identified and quantified using fluorescent dyes and fluorescently labelled antibodies in a flow cytometric assay. Fermentation chemistry was monitored using Fourier transform infrared (FTIR) spectroscopy, except for malic acid which was measured enzymatically. Malic acid utilization by O. oeni was greatest in the presence of the yeast Cepage. Growth of O. oeni was substantially slower in the presence of the yeast VL1. The three yeasts had similar fermentation rates in the presence and absence of O. oeni. CONCLUSIONS: Viable and nonviable yeast and bacterial populations can be rapidly discriminated in simultaneous malolactic-alcoholic wine fermentations using antibodies, fluorescent dyes and flow cytometry. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study using fluorescently labelled antibodies to discriminate and monitor yeast and bacterial populations in wine fermentations and offers a new approach to investigating microbial interactions in wine fermentations. 相似文献
993.
994.
A continuous parallel shaken bioreactor system, combining the advantages of shaken bioreactors with the advantages of continuous
fermentation, was specifically manufactured from quartz glass and provides a geometric accuracy of <1 mm. Two different model
systems (facultative anaerobic bacterium C. glutamicum, and Crabtree-negative yeast P. stipitis), whose growth behaviour and metabolite formation are affected by dilution rate and oxygen availability, were studied. The
transition from non-oxygen to limited conditions as function of the dilution rate could precisely be predicted applying the
approach described by Maier et al. (Biochem Eng J 17:155–167, 2004). In addition, the Crabtree-positive yeast S. cerevisiae was simultaneously studied in the continuous parallel shaken bioreactor system and in a conventional 1-L bioreactor, for
comparison. Essentially the same results were obtained in both types of bioreactors. However, many more reading points were
obtained with the parallel shaken bioreactor system in the same time at much lower consumption of culture media. 相似文献
995.
996.
Rodríguez Couto S 《Biotechnology journal》2008,3(7):859-870
Biological wastes contain several reusable substances of high value such as soluble sugars and fibre. Direct disposal of such wastes to soil or landfill causes serious environmental problems. Thus, the development of potential value-added processes for these wastes is highly attractive. These biological wastes can be used as support-substrates in solid-state fermentation (SSF) to produce industrially relevant metabolites with great economical advantage. In addition, it is an environmentally friendly method of waste management. This paper reviews the reutilization of biological wastes for the production of value-added products using the SSF technique. 相似文献
997.
998.
Pervaporation proved to be one of the best methods to remove solvents out of a solvent producing Clostridium acetobutylicum culture. By using an ionic liquid (IL)-polydimethylsiloxane (PDMS) ultrafiltration membrane (pore size 60 nm), we could guarantee
high stability and selectivity during all measurements carried out at 37°C. Overall solvent productivity of fermentation connected
with continuous product removal by pervaporation was 2.34 g l−1 h−1. The supported ionic liquid membrane (SILM) was impregnated with 15 wt% of a novel ionic liquid (tetrapropylammonium tetracyano-borate)
and 85 wt% of polydimethylsiloxane. Pervaporation, accomplished with the optimized SILM, led to stable and efficient removal
of the solvents butan-1-ol and acetone out of a C. acetobutylicum culture. By pervaporation through SILM, we removed more butan-1-ol than C. acetobutylicum was able to produce. Therefore, we added an extra dose of butan-1-ol to run fermentation on limiting values where the bacteria
would still be able to survive its lethal concentration (15.82 g/l). After pervaporation was switched off, the bacteria died
from high concentration of butan-1-ol, which they produced. 相似文献
999.
Biosynthesis and secretion of salusin-alpha from human cells 总被引:1,自引:0,他引:1
Salusins originally identified using bioinformatics analyses have been shown to act on the cardiovascular and endocrine systems. Although the hypotensive activity of salusin-alpha is limited, it exerts a significant anti-atherosclerotic effect via suppression of foam cell formation in human monocyte-derived macrophages by down-regulating acyl-CoA:cholesterol acyltransferase-1. Furthermore, serum salusin-alpha levels show a close negative correlation with the severity of atherosclerotic diseases. However, biosynthesis and secretion of salusin-alpha peptide from cultured mammalian cells have not been demonstrated to date. We examined the expression, synthesis and release of salusin-alpha in human-derived cell lines. Preprosalusin mRNA and protein were detected ubiquitously in all cells tested, whereas the processing of preprosalusin into salusin-alpha peptide is dependent upon each cell type. Immunohistochemical study revealed the most abundant salusin-alpha-like immunoreactivity to be present in HeLa cells which released salusin-alpha-like immunoreactivity into the culture supernatant. Analysis of extracted conditioned media from HeLa cells by reverse-phase high performance liquid chromatography coupled with radioimmunoassay detection revealed a single immunoreactive component that co-eluted with authentic salusin-alpha. These results present the first evidence that salusin-alpha is biosynthesized and released from human-derived cells. 相似文献
1000.
The aim of this work was to study the chemical structure and physical properties of water-soluble oligosaccharides (WSOS) produced by Gluconacetobacter hansenii PJK using the waste from beer fermentation broth as a basal medium. The analysis of the hydrolyzed products and the spectroscopic studies of the native WSOS showed that it is a mixture of oligomers all having a single sugar -linked glucuronic acid as building blocks with an O-acetyl and O-methyl group, in the terminal unit of the non-reducing end. The thermal studies displayed a progressive degradation of WSOS without a major weight loss throughout a range of temperatures. The melting point and pyrolysis temperature were found to be 130.16 and 275.25 °C, respectively. The optimum concentration of WSOS for a maximum emulsifying ability was found to be 0.10% (w/v). The resulting emulsions, however, did not demonstrate a noteworthy stability. 相似文献