全文获取类型
收费全文 | 327篇 |
免费 | 18篇 |
出版年
2021年 | 1篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2018年 | 5篇 |
2017年 | 5篇 |
2016年 | 9篇 |
2015年 | 6篇 |
2014年 | 10篇 |
2013年 | 20篇 |
2012年 | 21篇 |
2011年 | 19篇 |
2010年 | 8篇 |
2009年 | 5篇 |
2008年 | 10篇 |
2007年 | 20篇 |
2006年 | 17篇 |
2005年 | 15篇 |
2004年 | 14篇 |
2003年 | 23篇 |
2002年 | 21篇 |
2001年 | 5篇 |
2000年 | 3篇 |
1999年 | 8篇 |
1998年 | 6篇 |
1997年 | 13篇 |
1996年 | 6篇 |
1995年 | 9篇 |
1994年 | 4篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1986年 | 3篇 |
1985年 | 2篇 |
1984年 | 6篇 |
1983年 | 4篇 |
1982年 | 7篇 |
1981年 | 8篇 |
1980年 | 4篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1976年 | 4篇 |
1975年 | 2篇 |
1974年 | 3篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1967年 | 4篇 |
1965年 | 1篇 |
排序方式: 共有345条查询结果,搜索用时 15 毫秒
91.
Codon usage in nuclear genes of four monocot and three dicot species was analyzed to find general patterns in codon choice of plant species. Codon bias was correlated with GC content at the third codon position. GC contents were higher in monocot species than in dicot species at all codon positions. The high GC contents of monocot species might be the result of relatively strong mutational bias that occurred in the lineage of the Poaceae species. In both dicot and monocot species, the effective number of codons (ENCs) for most genes was similar to that for the expected ENCs based on the GC content at the third codon positions. G and C ending codons were detected as the "preferred" codons in monocot species, as in Drosophila. Also, many "preferred" codons are the same in dicot species. Pyrimidine (C and T) is used more frequently than purine (G and A) in four-fold degenerate codon groups. 相似文献
92.
Yoshiharu Nishida Kenichi Hirano Kosuke Tsukamoto Makoto Nagano Chiaki Ikegami Kirsten Roomp Mitsuaki Ishihara Naoki Sakane Zhongyan Zhang Ken-ichi Tsujii Ki Akifumi Matsuyama Tohru Ohama Fumihiko Matsuura Masato Ishigami Naohiko Sakai Hisatoyo Hiraoka Hiroaki Hattori Cheryl Wellington Yoshihide Yoshida Susumu Misugi Michael R Hayden Toru Egashira Shizuya Yamashita Yuji Matsuzawa 《Biochemical and biophysical research communications》2002,290(2):713-721
ATP-binding cassette transporter-1 (ABCA1) gene is mutated in patients with familial high-density lipoprotein deficiency (FHD). In order to know the molecular basis for FHD, we characterized three different ABCA1 mutations associated with FHD (G1158A/A255T, C5946T/R1851X, and A5226G/N1611D) with respect to their expression in the passaged fibroblasts from the patients and in the cells transfected with the mutated cDNAs. Fibroblasts from the all patients showed markedly decreased cholesterol efflux to apolipoprotein (apo)-Al. In the fibroblasts homozygous for G1158A/A255T, the immunoreactive mass of ABCA1 could not be detected, even when stimulated by 9-cis-retinoic acid and 22-R-hydroxycholesterol. In the fibroblasts homozygous for C5946T/R1851X, ABCA1 mRNA was comparable. Because the mutant ABCA1 protein (R1851X) was predicted to lack the epitope for the antibody used, we transfected FLAG-tagged truncated mutant (R1851X/ABCA1-FLAG) cDNA into Cos-7 cells, showing that the mutant protein expression was markedly reduced. The expression of N1611D ABCA1 protein was comparable in both fibroblasts and overexpressing cells, although cholesterol efflux from the cells was markedly reduced. These data indicated that, in the three patients investigated, the abnormalities and dysfunction of ABCA1 occurred at the different levels, providing important information about the expression, regulation, and function of ABCA1. 相似文献
93.
94.
Kazuo Yoshida Michio Hagiya Naohiko Yanagishima 《Biochemical and biophysical research communications》1976,71(4):1085-1094
The substance responsible for the sexual agglutinability was successfully solubilized by a newly established autoclaving method from the surface of mating type cells of and purified by DEAE cellulose chromatography, gel filtration, affinity chromatography and electrophoresis. The substance was found to consist of at least two different glycoprotein subunits. The molecular weight of the substance was estimated to be about 23,000 daltons by gel filtration. The substance was univalent in its biological activity and specifically masked the sexual agglutinability of the mating type α cells. The substance formed a complementary complex with the agglutination substance from α cells in vitro. 相似文献
95.
Chikashi Shimoda Naohiko Yanagishima Akira Sakurai Saburo Tamura 《Archives of microbiology》1976,108(1):27-33
A diffusible sex-specific substance called substance-I (S-I) was isolated from culture filtrate of type strains of the yeast Saccharomyces cerevisiae. The isolated S-I, an oligopeptide, induced sexual cell agglutinability in inducible a type strains and enhanced the agglutinability in constitutive a type strains. The induction of sexual agglutinability was detected in 30 min and reached maximum in 90 min, when 0.2 g/ml of S-I was added to inducible a type cells. The a type-specific factor responsible for sexual cell agglutination, called a type agglutination factor (aAF), was shown to be produced during the induction or the enhancement of agglutinability of a type cells by S-I. The aAF produced in response to S-I was not different in the susceptibility to proteolytic enzymes and disulfide-cleaving agents from those produced constitutively in the absence of S-I. 相似文献
96.
Summary The production of sex pheromones responsible for the induction of the sexual agglutination ability in the mutants of the mating type locus, mata1, mat1 and mat2, was examined. mata1 cells behaved just like wild-type MATa cells in the production of a pheromone and responsiveness to pheromone. On the other hand, mat1 cells showed neither a nor ability in the production of and the agglutination ability induction by sex pheromones. Cells carrying mat2 secreted a pheromone but not pheromone and showed the ability to inactivate pheromone. However, mat2 cells responded to neither a nor pheromone in the induction of sexual agglutionation ability. 相似文献
97.
S Kimura A Ichikawa J Ishizuka S Ohkouchi T Kake K Maruyama 《European journal of biochemistry》1999,263(2):396-401
Tropomodulin is a tropomyosin-binding protein, originally isolated from human erythrocytes. Tropomodulin is currently regarded as the sole actin pointed-end capping protein [Weber, A., Pennise, C.R., Babcock, G.G. & Fowler, V.M. (1994) J. Cell Biol. 127, 1627-1635]. This work first describes a procedure for the purification of tropomodulin from rabbit skeletal muscle. Tropomodulin almost completely inhibited filament formation of actin in the presence of tropomyosin and troponin. For the maximal inhibition of actin polymerization, approximately 0.10, 0.12 and 0.003 mol of tropomyosin, troponin and tropomodulin per mol of actin were required, respectively. Fluorescence-intensity measurements, electron-microscopy and sedimentation experiments revealed that only very short fragments and amorphous aggregates, but not filaments, were formed when actin was copolymerized with tropomyosin, troponin and tropomodulin by the addition of 50 mM KCl at pH 8.0. The effects of tropomyosin, troponin and tropomodulin were more remarkable on Ca-actin than on Mg-actin. It appears that tropomodulin caps both the pointed and barbed ends of tropomyosin- and troponin-bound actin filaments. 相似文献
98.
Shumpei?KitamuraEmail author Shunsuke?Suzuki Takakazu?Yumoto Phitaya?Chuailua Kamol?Plongmai Pilai?Poonswad Naohiko?Noma Tamaki?Maruhashi Chumphon?Suckasam 《Biodiversity and Conservation》2005,14(5):1241-1261
The diversity of plants in tropical forests makes dietary studies of frugivores difficult. This paper provides a botanical inventory of a tropical seasonal forest community in Khao Yai National Park, Thailand. The forest is valuable from a conservation perspective because it is one of the last remaining intact forests in northeastern Thailand, and is an important refuge for many animal and plant species. A 4-ha inventory plot measuring 200 × 200 m was established and all plants greater than or equal to 10 cm in diameter at breast height (dbh) were measured and permanently labeled. We found 1610 stems belonging to 105 species, 76 genera and 35 families, with a combined basal area of 142.5 m2. The community was dominated by species of Lauraceae, Cornaceae, Euphorbiaceae, Meliaceae, and Elaeocarpaceae. About one-third of the plant species (40 spp.) identified in this study were vulnerable to extinction because they were mostly dispersed by large frugivores, which were intolerant of human impact. If they disappear, these forests may become dominated by plant species that are dispersed by abiotic means and species with small-seeded fruits. 相似文献
99.
Approaches to repigmentation of vitiligo skin: new treatment with ultrasonic abrasion,seed-grafting and psoralen plus ultraviolet A therapy 总被引:3,自引:0,他引:3
Tsukamoto K Osada A Kitamura R Ohkouchi M Shimada S Takayama O 《Pigment cell research / sponsored by the European Society for Pigment Cell Research and the International Pigment Cell Society》2002,15(5):331-334
Vitiligo vulgaris is a common disease throughout the world although its pathogenesis is not yet known. The most frequent treatment used for vitiligo is PUVA (psoralen plus ultraviolet A) and topical steroids but against stable refractory vitiligo, various other surgical techniques have been developed such as autografting, epidermal grafting with suction blisters, epithelial sheet grafting, and transplantation of cultured melanocytes. We have discovered a new method using ultrasonic abrasion, seed-grafting and PUVA therapy. The ultrasonic surgical aspirator abrades only the epidermis of recipient sites. This easily and safely removes only the epidermis, even on spotty lesions or intricate regions which are difficult to remove using a conventional motor-driven grinder or liquid nitrogen. Epidermal seed-grafting can cover more area than sheet-grafting, and subsequent PUVA treatment can enlarge the area of pigmentation with coalescence of adjacent grafts. In this article, we provide a general overview of the current surgical therapies including our method for treating stable refractory vitiligo. 相似文献
100.