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961.
Yuta Okamoto Yuji Haraguchi Naoya Sawamura Toru Asahi Tatsuya Shimizu 《Biotechnology progress》2020,36(2):e2941
Mammalian cells have been used in various research fields. More recently, cultured cells have been used as the cell source of “cultured meat.” Cell cultivation requires media containing nutrients, of which glucose and amino acids are the essential ones. These nutrients are generally derived from grains or heterotrophic microorganisms, which also require various nutrients derived from grains. Grain culture, in turn, requires many chemical fertilizers and agrochemicals, which can cause greenhouse gas emission and environmental contamination. Furthermore, grain production is greatly influenced by environmental changes. In contrast, microalgae efficiently synthesize various nutrients using solar energy, water, and inorganic substances, which are widely used in the energy sector. In this study, we aimed to apply nutrients extracted from microalgae in the culture media for mammalian cell cultivation. Glucose was efficiently extracted from Chlorococcum littorale or Arthrospira platensis using sulfuric acid, whereas 18 of the 20 proteinogenic amino acids were efficiently extracted from Chlorella vulgaris using hydrochloric acid. We further investigated whether nutrients present in the algal extracts could be used in mammalian cell cultivation. Although almost all C2C12 mouse myoblasts died during cultivation in a glucose- and amino acid-free medium, the cell death was rescued by adding algal extract(s) into the nutrient-deficient media. This indicates that nutrients present in algal extracts can be used for mammalian cell cultivation. This study is the first step toward the establishment of a new cell culture system that can reduce environmental loads and remain unaffected by the impact of environmental changes. 相似文献
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965.
Masahito Tanaka Yuta Yamaji Yuken Fukano Kazuhiko Shimada Jun-Ichiro Ishibashi Tsuyoshi Hirajima 《Geomicrobiology journal》2013,30(6):538-548
Effectiveness of different pure and mixed cultures of three moderately thermophilic, extremely acidophilic bacterial strains (Acidimicrobium ferrooxidans ICP, Sulfobacillus sibiricus N1, Acidithiobacillus caldus KU) were investigated for biooxidation of highly refractory polymetallic gold ore concentrates. Despite of its complex mineralogy and the presence of a mixture of potentially inhibitory metals and metalloids, the concentrate was readily dissolved in defined mixed cultures including both iron and sulfur oxidizers, releasing as much as 80% of soluble Fe and 61% of soluble As. Factors to affect microbial mineral dissolution efficiencies (i.e. microbial As(III) oxidation ability, formation of secondary mineral precipitation (e.g. jarosite, elemental sulfur, scorodite, anglesite), and microbial population dynamics during biooxidation) were studied, based on which roles of individual microbes and their synergistic interactions during biooxidation were discussed. Applying the biooxidation pretreatment using the most efficient mixed cultures containing all three strains significantly improved the recovery of both Au (from 1.1% to 86%) and Ag (from 3.2% to 87%). Finally, this study provides one of the very few available comparisons of the effectiveness of different pretreatment techniques for refractory gold ore concentrates: Compared with other abiotic pretreatment approaches (roasting, pressure oxidation, and alkali dissolution), biooxidation was shown to be one of the most effective options in terms of the recovery of Au and Ag. 相似文献
966.
Yuko Kawaguchi Yinjie Yang Narutoshi Kawashiri Keisuke Shiraishi Masako Takasu Issay Narumi Katsuya Satoh Hirofumi Hashimoto Kazumichi Nakagawa Yoshiaki Tanigawa Yoh-hei Momoki Maiko Tanabe Tomohiro Sugino Yuta Takahashi Yasuyuki Shimizu Satoshi Yoshida Kensei Kobayashi Shin-ichi Yokobori Akihiko Yamagishi 《Origins of life and evolution of the biosphere》2013,43(4-5):411-428
967.
Hiroaki Tachiwana Yuta Miya Nobuaki Shono Jun-ichirou Ohzeki Akihisa Osakabe Koichiro Otake Vladimir Larionov William C. Earnshaw Hiroshi Kimura Hiroshi Masumoto Hitoshi Kurumizaka 《Nucleic acids research》2013,41(5):2869-2880
CENP-B is a widely conserved centromeric satellite DNA-binding protein, which specifically binds to a 17-bp DNA sequence known as the CENP-B box. CENP-B functions positively in the de novo assembly of centromeric nucleosomes, containing the centromere-specific histone H3 variant, CENP-A. At the same time, CENP-B also prevents undesired assembly of the CENP-A nucleosome through heterochromatin formation on satellite DNA integrated into ectopic sites. Therefore, improper CENP-B binding to chromosomes could be harmful. However, no CENP-B eviction mechanism has yet been reported. In the present study, we found that human Nap1, an acidic histone chaperone, inhibited the non-specific binding of CENP-B to nucleosomes and apparently stimulated CENP-B binding to its cognate CENP-B box DNA in nucleosomes. In human cells, the CENP-B eviction activity of Nap1 was confirmed in model experiments, in which the CENP-B binding to a human artificial chromosome or an ectopic chromosome locus bearing CENP-B boxes was significantly decreased when Nap1 was tethered near the CENP-B box sequence. In contrast, another acidic histone chaperone, sNASP, did not promote CENP-B eviction in vitro and in vivo and did not stimulate specific CENP-B binding to CENP-A nucleosomes in vitro. We therefore propose a novel mechanism of CENP-B regulation by Nap1. 相似文献
968.
Steven K Nishiyama D Walter Wray Kimberly Berkstresser Murali Ramaswamy Russell S Richardson 《Journal of applied physiology》2007,103(3):843-851
We sought to examine flow-mediated vasodilation (FMD) in both the arm [brachial artery (BA)] and lower leg [popliteal artery (PA)] of 12 young, healthy subjects. Vessel diameter, blood velocity, and calculated shear rate were determined with ultrasound Doppler following a suprasystolic cuff occlusion (5 min) in both the BA and PA and an additional reduced occlusion period (30-120 s) in the BA to more closely equate the shear stimulus observed in the PA. The BA revealed a smaller diameter and larger postischemic cumulative blood velocity [area under curve (AUC)] than the PA, a combination that resulted in an elevated postcuff cumulative shear rate (AUC) in the BA (BA: 25,419 +/- 2,896 s(-1).s, PA 8,089 +/- 1,048 s(-1).s; P < 0.05). Thus, when expressed in traditional terms, there was a tendency for the BA to have a greater FMD than the PA (6.5 +/- 1.0 and 4.5 +/- 0.8%, respectively; P = 0.1). However, when shear rate was experimentally matched (PA: 4.5 +/- 0.8%; BA: -0.4 +/- 0.4%) or mathematically normalized (PA: 6.8 x 10(-4) +/- 1.6 x 10(-4)%Delta/s(-1).s; BA: 2.5 x 10(-4) +/- 0.4 x 10(-4)%Delta/s(-1).s), the PA revealed a greater FMD per unit of shear rate than the BA (P < 0.05). These data highlight the importance of assessing the shear stimulus to which each vessel is exposed and reveal limb-specific differences in flow-mediated dilation. 相似文献
969.
Eri Nishiyama Yoshiyuki Ohtsubo Yuji Nagata Masataka Tsuda 《Environmental microbiology》2010,12(9):2539-2558
Burkholderia multivorans ATCC 17616 was originally isolated from a soil sample, and it carries three chromosomes. To identify traits of likely adaptive significance for colonization of soil, an in vivo expression technology system for ATCC 17616 was constructed using the promoterless and tandemly arranged dapB and lacZ genes as the reporters, and this system was applied to identify the genomic loci of ATCC 17616 that were induced in sterilized soil. Our screening of a library consisting of dapB‐lacZ‐inserted clones resulted in the isolation of 713 clones in which the insertion sites of genome were putatively transcribed in the soil but not in laboratory media. All insertion sites in the genome were determined by high‐throughput sequencing using genomic DNA as the templates, and subsequent analysis led to a reliable list of a total of 116 genomic loci as the B. m ultivorans ATCC 17616 l oci induced in a s oil environment (mls). These 116 mls carried the genes for energy acquisition from various substances, as well as genes for cell‐envelope integrity and the niche adaptation. The distribution of these loci was biased to the second chromosome, suggesting the importance of this replicon as a source of adaptive traits enhancing survival of this organism in natural environments. 相似文献
970.
Hideyuki Tanabe Issei Takayama Takashi Nishiyama Masashi Shimazaki Isao Kii Minqi Li Norio Amizuka Ken-ichi Katsube Akira Kudo 《PloS one》2010,5(8)