全文获取类型
收费全文 | 833篇 |
免费 | 54篇 |
出版年
2023年 | 2篇 |
2022年 | 6篇 |
2021年 | 27篇 |
2020年 | 13篇 |
2019年 | 11篇 |
2018年 | 25篇 |
2017年 | 10篇 |
2016年 | 21篇 |
2015年 | 49篇 |
2014年 | 54篇 |
2013年 | 61篇 |
2012年 | 56篇 |
2011年 | 58篇 |
2010年 | 25篇 |
2009年 | 18篇 |
2008年 | 52篇 |
2007年 | 46篇 |
2006年 | 26篇 |
2005年 | 25篇 |
2004年 | 27篇 |
2003年 | 32篇 |
2002年 | 27篇 |
2001年 | 13篇 |
2000年 | 25篇 |
1999年 | 15篇 |
1998年 | 7篇 |
1997年 | 10篇 |
1996年 | 5篇 |
1995年 | 6篇 |
1994年 | 10篇 |
1993年 | 9篇 |
1992年 | 11篇 |
1991年 | 17篇 |
1990年 | 10篇 |
1989年 | 13篇 |
1988年 | 6篇 |
1987年 | 5篇 |
1986年 | 8篇 |
1985年 | 3篇 |
1984年 | 8篇 |
1982年 | 6篇 |
1981年 | 6篇 |
1978年 | 2篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1974年 | 4篇 |
1970年 | 1篇 |
1968年 | 4篇 |
1967年 | 3篇 |
1966年 | 1篇 |
排序方式: 共有887条查询结果,搜索用时 15 毫秒
21.
Summary We constructed a series of defective mini-F plasmids, which have deletion(s) in the replication origin I and/or origin II, and their derivatives, which do not produce F3 protein, by insertion of the XhoI fragment of Tn5 into the XhoI site at 41.0 F (kilobases on the coordinate map of F-plasmid). Using these mutant mini-F plasmids, we found that F3 protein is essential for the replication of mini-F from origin I, but not from origin II. 相似文献
22.
Shotaro Hirase Ayumi Tezuka Atsushi J. Nagano Mana Sato Sho Hosoya Kiyoshi Kikuchi Wataru Iwasaki 《Evolution; international journal of organic evolution》2021,75(1):176-194
Hybridization between divergent lineages generates new allelic combinations. One mechanism that can hinder the formation of hybrid populations is mitonuclear incompatibility, that is, dysfunctional interactions between proteins encoded in the nuclear and mitochondrial genomes (mitogenomes) of diverged lineages. Theoretically, selective pressure due to mitonuclear incompatibility can affect genotypes in a hybrid population in which nuclear genomes and mitogenomes from divergent lineages admix. To directly and thoroughly observe this key process, we de novo sequenced the 747‐Mb genome of the coastal goby, Chaenogobius annularis, and investigated its integrative genomic phylogeographics using RNA‐sequencing, RAD‐sequencing, genome resequencing, whole mitogenome sequencing, amplicon sequencing, and small RNA‐sequencing. Chaenogobius annularis populations have been geographically separated into Pacific Ocean (PO) and Sea of Japan (SJ) lineages by past isolation events around the Japanese archipelago. Despite the divergence history and potential mitonuclear incompatibility between these lineages, the mitogenomes of the PO and SJ lineages have coexisted for generations in a hybrid population on the Sanriku Coast. Our analyses revealed accumulation of nonsynonymous substitutions in the PO‐lineage mitogenomes, including two convergent substitutions, as well as signals of mitochondrial lineage‐specific selection on mitochondria‐related nuclear genes. Finally, our data implied that a microRNA gene was involved in resolving mitonuclear incompatibility. Our integrative genomic phylogeographic approach revealed that mitonuclear incompatibility can affect genome evolution in a natural hybrid population. 相似文献
23.
24.
Y. Kondo K. Sho M. A. Majid F. Okajima 《Nucleosides, nucleotides & nucleic acids》2013,32(5):1217-1218
Abstract In thyroid cells, a PI-agonist, via G1 like protein, enhanced a TSH-induced I?-efflux by intensifying a TSH-dependent inositol polyphosphate production followed by a Ca2+ mobilization, but diminished a TSH-dependent DNA synthesis by attenuating a TSH-dependent cAMP accumulation. 相似文献
25.
Noboru Asada Yoshio Katayama Mari Sato Kentaro Minagawa Kanako Wakahashi Hiroki Kawano Yuko Kawano Akiko Sada Kyoji Ikeda Toshimitsu Matsui Mitsune Tanimoto 《Cell Stem Cell》2013,12(6):737-747
- Download : Download high-res image (522KB)
- Download : Download full-size image
26.
The genome of influenza A virus consists of eight-segmented, single-stranded, negative-sense viral RNAs (vRNAs). Each vRNA contains a central coding region that is flanked by noncoding regions. It has been shown that upon virion formation, the eight vRNAs are selectively packaged into progeny virions through segment-specific packaging signals that are located in both the terminal coding regions and adjacent noncoding regions of each vRNA. Although recent studies using next-generation sequencing suggest that multiple intersegment interactions are involved in genome packaging, contributions of the packaging signals to the intersegment interactions are not fully understood. Herein, using synthesized full-length vRNAs of H1N1 WSN (A/WSN/33 [H1N1]) virus and short vRNAs containing the packaging signal sequences, we performed in vitro RNA binding assays and identified 15 intersegment interactions among eight vRNAs, most of which were mediated by the 3′- and 5′-terminal regions. Interestingly, all eight vRNAs interacted with multiple other vRNAs, in that some bound to different vRNAs through their respective 3′- and 5′-terminal regions. These in vitro findings would be of use in future studies of in vivo vRNA–vRNA interactions during selective genome packaging. 相似文献
27.
Faviel A. López-Romero Claudia Klimpfinger Sho Tanaka Jürgen Kriwet 《Journal of fish biology》2020,97(1):212-224
Chlamydoselachus anguineus, Garman 1884, commonly called the frilled shark, is a deep-sea shark species occurring up to depths of 1300 m. It is assumed to represent an ancient morphotype of sharks (e.g., terminal mouth opening, more than five gill slits) and thus is often considered to represent plesiomorphic traits for sharks. Therefore, its early ontogenetic developmental traits are important for understanding the evolution of its particular phenotype. Here, we established six stages for prenatal embryos and used linear measurements and geometric morphometrics to analyse changes in shape and size as well as their timing during different embryonic stages. Our results show a change in head shape and a relocation of the mouth opening at a late stage of development. We also detected a negative allometric growth of the head and especially the eye compared to the rest of the body and a sexual dimorphism in total body length, which differs from the known data for adults. A multivariate analysis of covariance shows a significant interaction of shape related to the logarithm of centroid size and developmental stage. Geometric morphometrics results indicate that the head shape changes as a covariate of body size while not accounting for differences between sexes. The growth pattern of stages 32 and 33 indicates a shift in head shape, thus highlighting the moment in development when the jaws start to elongate anteriorly to finally achieve the adult condition of terminal mouth opening rather than retaining the early embryonic subterminal position as is typical for sharks. Thus, the antero-terminal mouth opening of the frilled shark has to be considered a derived feature. 相似文献
28.
Shengchen Tao Daiju Yamazaki Shinji Komazaki Chengzhu Zhao Tsunaki Iida Sho Kakizawa Yuji Imaizumi Hiroshi Takeshima 《The Journal of biological chemistry》2013,288(22):15581-15589
The TRIC channel subtypes, namely TRIC-A and TRIC-B, are intracellular monovalent cation-specific channels and likely mediate counterion movements to support efficient Ca2+ release from the sarco/endoplasmic reticulum. Vascular smooth muscle cells (VSMCs) contain both TRIC subtypes and two Ca2+ release mechanisms; incidental opening of ryanodine receptors (RyRs) generates local Ca2+ sparks to induce hyperpolarization and relaxation, whereas agonist-induced activation of inositol trisphosphate receptors produces global Ca2+ transients causing contraction. Tric-a knock-out mice develop hypertension due to insufficient RyR-mediated Ca2+ sparks in VSMCs. Here we describe transgenic mice overexpressing TRIC-A channels under the control of a smooth muscle cell-specific promoter. The transgenic mice developed congenital hypotension. In Tric-a-overexpressing VSMCs from the transgenic mice, the resting membrane potential decreased because RyR-mediated Ca2+ sparks were facilitated and cell surface Ca2+-dependent K+ channels were hyperactivated. Under such hyperpolarized conditions, L-type Ca2+ channels were inactivated, and thus, the resting intracellular Ca2+ levels were reduced in Tric-a-overexpressing VSMCs. Moreover, Tric-a overexpression impaired inositol trisphosphate-sensitive stores to diminish agonist-induced Ca2+ signaling in VSMCs. These altered features likely reduced vascular tonus leading to the hypotensive phenotype. Our Tric-a-transgenic mice together with Tric-a knock-out mice indicate that TRIC-A channel density in VSMCs is responsible for controlling basal blood pressure at the whole-animal level. 相似文献
29.
30.