全文获取类型
收费全文 | 747篇 |
免费 | 23篇 |
专业分类
770篇 |
出版年
2024年 | 3篇 |
2023年 | 3篇 |
2022年 | 9篇 |
2021年 | 17篇 |
2020年 | 7篇 |
2019年 | 5篇 |
2018年 | 8篇 |
2017年 | 11篇 |
2016年 | 14篇 |
2015年 | 24篇 |
2014年 | 24篇 |
2013年 | 54篇 |
2012年 | 29篇 |
2011年 | 38篇 |
2010年 | 24篇 |
2009年 | 32篇 |
2008年 | 34篇 |
2007年 | 46篇 |
2006年 | 33篇 |
2005年 | 47篇 |
2004年 | 40篇 |
2003年 | 45篇 |
2002年 | 53篇 |
2001年 | 5篇 |
2000年 | 3篇 |
1999年 | 12篇 |
1998年 | 12篇 |
1997年 | 9篇 |
1996年 | 10篇 |
1995年 | 9篇 |
1994年 | 10篇 |
1993年 | 15篇 |
1992年 | 7篇 |
1991年 | 5篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1988年 | 6篇 |
1987年 | 6篇 |
1986年 | 9篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1983年 | 7篇 |
1982年 | 3篇 |
1980年 | 7篇 |
1978年 | 3篇 |
1975年 | 4篇 |
1974年 | 1篇 |
1972年 | 5篇 |
1971年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有770条查询结果,搜索用时 0 毫秒
1.
A new assay system for the detection of nicotianamine amino-transferase activity was developed. The activity of nicotianamine amino-transferase which participated in biosynthetic pathway of MAs from methionine in graminaceous plants was induced by the iron deficiency treatment. 相似文献
2.
Katayama Kazuhiro Hosui Atsushi Sakai Yoshiyuki Itou Minoru Matsuzaki Yasushi Takamori Yoriyuki Hosho Keiko Tsuru Tomomi Takikawa Yasuhiro Michitaka Kojiro Ogawa Eishin Miyoshi Yoko Ito Toshifumi Ida Shinobu Hamada Izumi Miyoshi Katsunori Kodama Hiroko Takehara Tetsuo 《Biological trace element research》2020,195(1):71-81
Biological Trace Element Research - The essential trace element zinc maintains liver functions. Liver diseases can alter overall zinc concentrations, and hypozincemia is associated with various... 相似文献
3.
Okada E Yamazaki M Tanabe M Takeuchi T Nanno M Oshima S Okamoto R Tsuchiya K Nakamura T Kanai T Hibi T Watanabe M 《American journal of physiology. Gastrointestinal and liver physiology》2005,288(4):G745-G754
We have previously demonstrated that mucosal CD4(+) T cells expressing high levels of IL-7 receptor (IL-7R(high)) are pathogenic cells responsible for chronic colitis. Here we investigate whether IL-7 is directly involved in the expansion of IL-7R(high) memory CD4(+) mucosal T cells and the exacerbation of colitis. We first showed that CD4(+) lamina propria lymphocytes (LPLs) from wild-type, T cell receptor-alpha-deficient (TCR-alpha(-/-)), and recombinase-activating gene (RAG)-2(-/-)-transferred mice with or without colitis showed phenotypes of memory cells, but only CD4(+) LPLs from colitic mice showed IL-7R(high). In vitro stimulation by IL-7, but not by IL-15 and thymic stromal lymphopoietin, enhanced significant proliferative responses and survival of colitic CD4(+), but not normal CD4(+) LPLs. Importantly, in vivo administration of IL-7 mice accelerated the expansion of IL-7R(high) memory CD4(+) LPLs and thereby exacerbated chronic colitis in RAG-2(-/-) mice transferred with CD4(+) LPLs from colitic TCR-alpha(-/-) mice. Conversely, the administration of anti-IL-7R monoclonal antibody significantly inhibited the development of TCR-alpha(-/-) colitis with decreased expansion of CD4(+) LPLs. Collectively, the present data indicate that IL-7 is essential for the expansion of pathogenic memory CD4(+) T cells under pathological conditions. Therefore, therapeutic approaches targeting the IL-7R pathway may be feasible in the treatment of human inflammatory bowel disease. 相似文献
4.
Comprehensive analysis of NAC family genes in Oryza sativa and Arabidopsis thaliana. 总被引:5,自引:0,他引:5
5.
Satoshi Yamamoto Kenji Minami Keiichi Fukaya Kohji Takahashi Hideki Sawada Hiroaki Murakami Satsuki Tsuji Hiroki Hashizume Shou Kubonaga Tomoya Horiuchi Masamichi Hongo Jo Nishida Yuta Okugawa Ayaka Fujiwara Miho Fukuda Shunsuke Hidaka Keita W. Suzuki Masaki Miya Hitoshi Araki Hiroki Yamanaka Atsushi Maruyama Kazushi Miyashita Reiji Masuda Toshifumi Minamoto Michio Kondoh 《PloS one》2016,11(3)
Recent studies in streams and ponds have demonstrated that the distribution and biomass of aquatic organisms can be estimated by detection and quantification of environmental DNA (eDNA). In more open systems such as seas, it is not evident whether eDNA can represent the distribution and biomass of aquatic organisms because various environmental factors (e.g., water flow) are expected to affect eDNA distribution and concentration. To test the relationships between the distribution of fish and eDNA, we conducted a grid survey in Maizuru Bay, Sea of Japan, and sampled surface and bottom waters while monitoring biomass of the Japanese jack mackerel (Trachurus japonicus) using echo sounder technology. A linear model showed a high R2 value (0.665) without outlier data points, and the association between estimated eDNA concentrations from the surface water samples and echo intensity was significantly positive, suggesting that the estimated spatial variation in eDNA concentration can reflect the local biomass of the jack mackerel. We also found that a best-fit model included echo intensity obtained within 10–150 m from water sampling sites, indicating that the estimated eDNA concentration most likely reflects fish biomass within 150 m in the bay. Although eDNA from a wholesale fish market partially affected eDNA concentration, we conclude that eDNA generally provides a ‘snapshot’ of fish distribution and biomass in a large area. Further studies in which dynamics of eDNA under field conditions (e.g., patterns of release, degradation, and diffusion of eDNA) are taken into account will provide a better estimate of fish distribution and biomass based on eDNA. 相似文献
6.
Goldar MM Nishie T Ishikura Y Fukuda T Takegawa K Kawamukai M 《Bioscience, biotechnology, and biochemistry》2005,69(7):1422-1426
The moc1/sds23 gene was isolated to induce sexual development of a sterile strain due to overexpression of adenylate cyclase in Schizosaccharomyces pombe. Here, we studied the functional conservation between moc1/sds23 and its two orthologs SDS23 and SDS24 in Saccharomyces cerevisiae. We observed that the temperature sensitivity, salt tolerance, cell morphology, and sterility of the Deltamoc1 mutant in S. pombe were recovered by expressing either S. cerevisiae SDS23 or SDS24. We found that deletion of both SDS23 and SDS24 resulted in the production of a large vacuole that was reversed by the expression of S. pombe moc1/sds23. In these ways we found that S. pombe Moc1/Sds23 and S. cerevisiae SDS23p or SDS24p are functional homologs. In addition we found that the Deltasds23 Deltasds24 diploid strain reduces cell separation in forming pseudohyphal-like growth in S. cerevisiae. Thus S. pombe moc1/sds23 and S. cerevisiae SDS23 or SDS24 are interchangeable with each other, but their disruptants are phenotypically dissimilar. 相似文献
7.
The intestinal epithelium is the largest surface area that is exposed to various pathogens in the environment, however, in contrast to the colon the number of bacteria that colonize the small intestine is extremely low. Paneth cells, one of four major epithelial cell lineages in the small intestine, reside at the base of the crypts and have apically oriented secretory granules. These granules contain high levels of antimicrobial peptides that belong to the alpha-defensin family. Paneth cells secrete these microbicidal granules that contain alpha-defensins when exposed ex vivo to bacteria or their antigens, and recent evidence reveals that antimicrobial peptides, particularly alpha-defensins, that are present in Paneth cells contribute to intestinal innate host defense. 相似文献
8.
Minami Kanako Ueda Nanami Ishimoto Kaichi Tsujiuchi Toshifumi 《Molecular and cellular biochemistry》2020,465(1-2):89-102
Molecular and Cellular Biochemistry - Parkinson’s disease (PD) is the second common age-related neurodegenerative disease. It is characterized by control loss of voluntary movements control,... 相似文献
9.
10.
Extensive and prolonged restoration of dystrophin expression with vivo-morpholino-mediated multiple exon skipping in dystrophic dogs 总被引:1,自引:0,他引:1
Yokota T Nakamura A Nagata T Saito T Kobayashi M Aoki Y Echigoya Y Partridge T Hoffman EP Takeda S 《Nucleic acid therapeutics》2012,22(5):306-315
Duchenne muscular dystrophy (DMD) is a severe and the most prevalent form of muscular dystrophy, characterized by rapid progression of muscle degeneration. Antisense-mediated exon skipping is currently one of the most promising therapeutic options for DMD. However, unmodified antisense oligos such as morpholinos require frequent (weekly or bi-weekly) injections. Recently, new generation morpholinos such as vivo-morpholinos are reported to lead to extensive and prolonged dystrophin expression in the dystrophic mdx mouse, an animal model of DMD. The vivo-morpholino contains a cell-penetrating moiety, octa-guanidine dendrimer. Here, we sought to test the efficacy of multiple exon skipping of exons 6-8 with vivo-morpholinos in the canine X-linked muscular dystrophy, which harbors a splice site mutation at the boundary of intron 6 and exon 7. We designed and optimized novel antisense cocktail sequences and combinations for exon 8 skipping and demonstrated effective exon skipping in dystrophic dogs in vivo. Intramuscular injections with newly designed cocktail oligos led to high levels of dystrophin expression, with some samples similar to wild-type levels. This is the first report of successful rescue of dystrophin expression with morpholino conjugates in dystrophic dogs. Our results show the potential of phosphorodiamidate morpholino oligomer conjugates as therapeutic agents for DMD. 相似文献