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81.
82.
From lignocellulosic residues to market: Production and commercial potential of xylooligosaccharides
Cláudia Amorim Sara C. Silvério Kristala L.J. Prather Lígia R. Rodrigues 《Biotechnology advances》2019,37(7):107397
The updated definition of prebiotic expands the range of potential applications in which emerging xylooligosaccharides (XOS) can be used. It has been demonstrated that XOS exhibit prebiotic effects at lower amounts compared to others, making them competitively priced prebiotics. As a result, the industry is focused on developing alternative approaches to improve processes efficiency that can meet the increasing demand while reducing costs. Recent advances have been made towards greener and more efficient processes, by applying process integration strategies to produce XOS from costless lignocellulosic residues and using genetic engineering to create microorganisms that convert these residues to XOS. In addition, collecting more in vivo data on their performance will be key to achieve regulatory claims, greatly increasing XOS commercial value. 相似文献
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《Saudi Journal of Biological Sciences》2022,29(2):822-830
The objective of this present research is to use agricultural residues as a source of energy for heating greenhouses during winter seasons and sequestrating soil carbon dioxide through adding biochar to the soil media. To fulfill the objective of the research work, summer squash was transplanted in a constructed greenhouse and heated using an attached biomass-burning system. The performance of the attached biomass-burning system was experimentally studied under different agricultural residues (corn stalks, cotton stalks and okra stalks), heating fluids (water and oil) and air fan operating periods (10, 15 and 20 min/h). Results indicated that the biomass-burning system allowed increasing temperature and relative humidity inside the greenhouse up to 27.2 and 80 %, respectively. The maximum biomass-burning system efficiency of 81 % was achieved with the use of okra stalks as a source of energy and oil as a heating fluid side by side with adjusting the suction fan operating period at 15 min/h. Adding bio-charcoal to the soil media, enhanced the soil carbon, resulting in a total fresh yield of 3.7 and 2.9 kg/pot with a total number of leaves per plant of 55 and 47 leaves under conditions of with and without charcoal addition, respectively. 相似文献
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A 2‐year study was performed in two sites in southern France to assess the effect of ivermectin residues on the attractiveness of cattle dung to colonizing insects. Insect captures were compared between pitfall traps baited with dung from untreated cattle and dung from cattle that had been treated with a slow‐release (SR) bolus of ivermectin. Cattle dung was collected at different times after treatment (4, 14, 42, 70 and 98 days). Excretion showed a plateau, with levels ranging between 0.688 µg and 1.123 µg ivermectin per gram of wet dung. Faecal residues affected insect captures at both sites. Effects were independent of the time dung was collected after treatment, except for one result subsequent to a severe drought during the baiting period. Ivermectin‐contaminated dung showed a significant attractive effect, with increased captures regardless of the guild to which beetles belonged. This study demonstrates the attractiveness of ivermectin residues over a long period after the treatment of animals. It draws attention to the danger of widespread use of this endectocide‐based SR bolus, which is attributable to the preferential attraction of insects to treated dung, which potentially puts at risk the survival of their offspring. 相似文献
87.
The luncheon meat samples analyzed, which were produced locally by the two main luncheon meat producing companies in Egypt
were relatively highly contaminated either by moulds and yeasts in general, aflatoxigenic species and aflatoxin residues in
particular. The most frequently encountered fungi from the samples were yeasts, Aspergillus niger, A. flavus, Penicillium chrysogenum, Rhizopus stolonifer, Mucor circinelloides. Less common were Cladosporium sphaerospermum, Alternaria alternata, Mycosphaerella tassiana, P. aurantiogriseum and P. oxalicum. The most important aflatoxigenic species, A. flavus, was isolated frequently. It was 10% of the total fungal isolates from both samples of the two companies. Seven luncheon
meat samples out of 50 analyzed were positive for aflatoxin B1 or B1 and G1, while all samples were negative for aflatoxins B2, G2, M1 and M2. Aflatoxin B1 was detected only in 4 and 3 samples out of 25 analyzed from each of company A and B, respectively. The highest detectable
level, 11.1 ppb, was recorded in a sample from company B and the least, 0.5 ppb, in a sample from company A. Aflatoxin G1, at concentration of 3.2 ppb, was detected in only one sample of the aflatoxin B1 – contaminated 3 samples of company B: this sample also had the highest level of aflatoxin B1. Some luncheon meat samples had higher numbers of aflatoxigenic A. flavus than others, however these samples were negative for aflatoxins. The hazardous potential of such contamination will be discussed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
88.
Multiple-sequence alignment of glycoside hydrolase (GH) families 32, 43, 62, and 68 revealed three conserved blocks, each containing an acidic residue at an equivalent position in all the enzymes. A detailed analysis of the site-directed mutations so far performed on invertases (GH32), arabinanases (GH43), and bacterial fructosyltransferases (GH68) indicated a direct implication of the conserved residues Asp/Glu (block I), Asp (block II), and Glu (block III) in substrate binding and hydrolysis. These residues are close in space in the 5-bladed beta-propeller fold determined for Cellvibrio japonicus alpha-L-arabinanase Arb43A [Nurizzo et al., Nat Struct Biol 2002;9:665-668] and Bacillus subtilis endo-1,5-alpha-L-arabinanase. A sequence-structure compatibility search using 3D-PSSM, mGenTHREADER, INBGU, and SAM-T02 programs predicted indistinctly the 5-bladed beta-propeller fold of Arb43A and the 6-bladed beta-propeller fold of sialidase/neuraminidase (GH33, GH34, and GH83) as the most reliable topologies for GH families 32, 62, and 68. We conclude that the identified acidic residues are located at the active site of a beta-propeller architecture in GH32, GH43, GH62, and GH68, operating with a canonical reaction mechanism of either inversion (GH43 and likely GH62) or retention (GH32 and GH68) of the anomeric configuration. Also, we propose that the beta-propeller architecture accommodates distinct binding sites for the acceptor saccharide in glycosyl transfer reaction. 相似文献
89.
R.?Mohan C.?R.?SoccolEmail author M.?Quoirin A.?Pandey 《In vitro cellular & developmental biology. Plant》2004,40(4):408-411
Summary Studies were carried out to evaluate sugarcane bagasse as an alternative to agar for micropropagation of apple clones to reduce
the cost of micropropagation and improve the quality of the propagules. Significant improvement in the in vitro rooting process, coupled with cost reduction, were obtained by the use of sugarcane bagasse as a substitute for the traditionally
used agar-gelled medium. The tests were undertaken with micro-cuttings of the apple rootstock Marubakaido (Malus prunifolia Borkh.) using a rooting medium composed of half-strength Murashige and Skoog salts and vitamins, 3% (w/v) sucrose, and 0.49
μM indole-3-butyric acid. The plants grown on sugarcane bagasse yielded a 22% increase in root length, 20% increase in plant
length, and 63% increase in the number of roots, compared with agar-grown micro-cuttings. Particle size of the sugarcane bagasse
had a significant impact on all those parameters, and the best results were obtained with bagasse comprising particles smaller
than 0.18 mm. The results demonstrated that the sugarcane bagasse could be used effectively as a substitute for agar during
rooting of apple shoots. 相似文献
90.
Structural characterization of transglutaminase-catalyzed cross-linking between glyceraldehyde 3-phosphate dehydrogenase and polyglutamine repeats
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Ruoppolo M Orrù S Francese S Caputo I Esposito C 《Protein science : a publication of the Protein Society》2003,12(1):170-179
The accumulation of abnormal polyglutamine-containing protein aggregates within the cytosol and nuclei of affected neurons is a hallmark of the progressive neurodegenerative disorders caused by an elongated (CAG)(n) repeat in the genome. The polyglutamine domains are excellent substrates for the enzyme transglutaminase type 2 (tissue), resulting in the formation of cross-links with polypeptides containing lysyl groups. Enzymatic activity toward the Q(n) domains increases greatly upon lengthening of such Q(n) stretches (n > 40). Among the possible amine donors, the glycolytic enzyme glyceraldehyde-3-phosphate-dehydrogenase was shown to tightly bind several proteins involved in polyglutamine expansion diseases. Recently, the authors have shown that K191, K268, and K331, out of the 26 lysines present in glyceraldehyde-3-phosphate-dehydrogenase, are the reactive amine-donor sites forming cross-links with substance P, which bears the simplest Q(n) domain (n = 2). The present study reports that synthetic peptides of both pathological and nonpathological length (n = 43 and 17, respectively) form cross-links with the same K residues located in the C-terminal region of glyceraldehyde-3-phosphate-dehydrogenase. In addition, it is shown that extra K residues present in the C termini of glyceraldehyde-3-phosphate-dehydrogenase are susceptible to cross-linking in the presence of transglutaminase. The present results indicate a possible modulating effect of Q(n) stretches on tissue transglutaminase substrate specificity and mechanism of recognition. 相似文献