全文获取类型
收费全文 | 488篇 |
免费 | 26篇 |
出版年
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 8篇 |
2020年 | 4篇 |
2019年 | 3篇 |
2018年 | 6篇 |
2016年 | 9篇 |
2015年 | 18篇 |
2014年 | 22篇 |
2013年 | 37篇 |
2012年 | 28篇 |
2011年 | 27篇 |
2010年 | 20篇 |
2009年 | 16篇 |
2008年 | 25篇 |
2007年 | 35篇 |
2006年 | 18篇 |
2005年 | 37篇 |
2004年 | 38篇 |
2003年 | 29篇 |
2002年 | 36篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 5篇 |
1998年 | 12篇 |
1997年 | 8篇 |
1996年 | 1篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 7篇 |
1991年 | 3篇 |
1990年 | 5篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 5篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 4篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1966年 | 1篇 |
排序方式: 共有514条查询结果,搜索用时 15 毫秒
101.
Characteristic microbial community of a dry thermophilic methanogenic digester: its long-term stability and change with feeding 总被引:1,自引:0,他引:1
Tang YQ Ji P Hayashi J Koike Y Wu XL Kida K 《Applied microbiology and biotechnology》2011,91(5):1447-1461
Thermophilic dry anaerobic digestion of sludge for cellulose methanization was acclimated at 53 °C for nearly 5 years using
a waste paper-based medium. The stability of the microbial community structure and the microbial community responsible for
the cellulose methanization were studied by 16S rRNA gene-based clone library analysis. The microbial community structure
remained stable during the long-term acclimation period. Hydrogenotrophic methanogens dominated in methanogens and Methanothermobacter, Methanobacterium, Methanoculleus, and Methanosarcina were responsible for the methane production. Bacteria showed relatively high diversity and distributed mainly in the phyla
Firmicutes, Bacteroidetes, and Synergistetes. Ninety percent of operational taxonomic units (OTUs) were affiliated with the phylum Firmicutes, indicating the crucial roles of this phylum in the digestion. Relatives of Clostridium stercorarium, Clostridium thermocellum, and Halocella cellulosilytica were dominant cellulose degraders. The acclimated stable sludge was used to treat garbage stillage discharged from a fuel
ethanol production process, and the shift of microbial communities with the change of feed was analyzed. Both archaeal and
bacterial communities had obviously changed: Methanoculleus spp. and Methanothermobacter spp. and the protein- and fatty acid-degrading bacteria became dominant. Accumulation of ammonia as well as volatile fatty
acids led to the inhibition of microbial activity and finally resulted in the deterioration of methane fermentation of the
garbage stillage. 相似文献
102.
103.
Hiroshi Sakane Yukimi Horii Satoru Nogami Yoji Kawano Takako Kaneko-Kawano Hiromichi Shirataki 《PloS one》2014,9(4)
Membrane traffic plays a crucial role in delivering proteins and lipids to their intracellular destinations. We previously identified α-taxilin as a binding partner of the syntaxin family, which is involved in intracellular vesicle traffic. α-Taxilin is overexpressed in tumor tissues and interacts with polymerized tubulin, but the precise function of α-taxilin remains unclear. Receptor proteins on the plasma membrane are internalized, delivered to early endosomes and then either sorted to the lysosome for degradation or recycled back to the plasma membrane. In this study, we found that knockdown of α-taxilin induced the lysosomal degradation of transferrin receptor (TfnR), a well-known receptor which is generally recycled back to the plasma membrane after internalization, and impeded the recycling of transferrin. α-Taxilin was immunoprecipitated with sorting nexin 4 (SNX4), which is involved in the recycling of TfnR. Furthermore, knockdown of α-taxilin decreased the number and length of SNX4-positive tubular structures. We report for the first time that α-taxilin interacts with SNX4 and plays a role in the recycling pathway of TfnR. 相似文献
104.
105.
106.
Yoji Wachi Koji Sode Kenichi Horikoshi Haruko Takeyama Tadashi Matsunaga 《Biotechnology Techniques》1995,9(9):633-636
Summary Inhibitors of melanin biosynthesis from marine microalgae were screened against a melanin-producing microorganism, Streptomyces bikiniensis. From 28 marine microalgal strains, 5 were found showing inhibitory activity. Of these, the extracts (50l, 2g total organic carbon/l) from two marine green algae showed strongly inhibited melanin biosynthesis, but showed less than 30 % inhibitory activity against mushroom tyrosinase. 相似文献
107.
Among bacterial, fungal and viral sialidases, the sialidase from Arthrobacter ureafaciens has the unique property of cleaving sialic acids linked to the internal galactose of gangliotetraose. In this study, we examined the ability to cleave the internal sialic acids of GM1 and fucosyl GM1 of sialidases from several bacterial and fungal origins, including Clostridium perfringens and Vibrio cholerae. We found that A. ureafaciens sialidase could liberate the sialic acid of GM1 at the highest rate, and was the only enzyme which could cleave fucosyl GM1 among the sialidases examined.The affinity-purified sialidase derived from the culture medium of A. ureafaciens was comprised of four isoenzymes with different molecular weights and isoelectric points, the isoenzymes that cleaved fucosyl GM1 being L (88 kDa, pI 5.0), M1 (66 kDa, pI 6.2) and M2 (66 kDa, pI 5.5), but not S (52 kDa, pI 6.2) which showed the highest specific activity toward colominic acid among the four isoenzymes. Abbreviations: SA, sialic acid; PBS, phosphate-buffered saline; PVP, polyvinylpyrrolidone; FABMS, fast atom bombardment mass spectrometry; Galint, internal galactose of Gg4Cer; Galext, external galactose of Gg4Cer 相似文献
108.
109.
Akifumi S. Tanabe Satoshi Nagai Kohsuke Hida Motoshige Yasuike Atushi Fujiwara Yoji Nakamura Yoshihito Takano Seiji Katakura 《Molecular ecology resources》2016,16(2):402-414
The nuclear 18S‐rRNA gene has been used as a metabarcoding marker in massively parallel sequencing (MPS)‐based environmental surveys for plankton biodiversity research. However, different hypervariable regions have been used in different studies, and their utility has been debated among researchers. In this study, detailed investigations into 18S‐rRNA were carried out; we investigated the effective number of sequences deposited in international nucleotide sequence databases (INSDs), the amplification bias, and the amplicon sequence variability among the three variable regions, V1–3, V4–5 and V7–9, using in silico polymerase chain reaction (PCR) amplification based on INSDs. We also examined the primer universality and the taxonomic identification power, using MPS‐based environmental surveys in the Sea of Okhotsk, to determine which region is more useful for MPS‐based monitoring. The primer universality was not significantly different among the three regions, but the number of sequences deposited in INSDs was markedly larger for the V4–5 region than for the other two regions. The sequence variability was significantly different, with the highest variability in the V1–3 region, followed by the V7–9 region, and the lowest variability in the V4–5 region. The results of the MPS‐based environmental surveys showed significantly higher identification power in the V1–3 and V7–9 regions than in the V4–5 region, but no significant difference was detected between the V1–3 and V7–9 regions. We therefore conclude that the V1–3 region will be the most suitable for future MPS‐based monitoring of natural eukaryote communities, as the number of sequences deposited in INSDs increases. 相似文献
110.
Yoji Nagashima Yoshiharu Ohaki Makoto Umeda Mitsuo Oshimura Kazuaki Misugi 《Virchows Archiv. B, Cell pathology including molecular pathology》1989,57(1):383-392
A new cell line designated ENU-T-1 has been established from a xenotransplanted experimental rat nephroblastoma. The cultured
cells are spindle-shaped or polygonal and are arranged in a wavy fashion morphologically similar to cultured embryonal renal
epithelial cells. The cells exhibit a number of epithelial characteristics. Enzyme histochemistry gives positive reactions
for gammaglutamyltranspeptidase and alkaline phosphatase, both of which are present in renal tubular epithelial cells. Immunofluorescence
studies show positive reactions for vimentin and cytokeratin. When inoculated into athymic nude mice, the cultured cells form
tumors composed of sheets of epithelial cells with focal tubular formation.
This cell line may be of value in studying differentiation of nephroblastoma, and possibly normal nephrogenesis. 相似文献