全文获取类型
收费全文 | 1464篇 |
免费 | 136篇 |
国内免费 | 2篇 |
专业分类
1602篇 |
出版年
2022年 | 9篇 |
2021年 | 8篇 |
2020年 | 8篇 |
2019年 | 10篇 |
2018年 | 11篇 |
2017年 | 6篇 |
2016年 | 23篇 |
2015年 | 32篇 |
2014年 | 38篇 |
2013年 | 138篇 |
2012年 | 49篇 |
2011年 | 69篇 |
2010年 | 43篇 |
2009年 | 48篇 |
2008年 | 80篇 |
2007年 | 66篇 |
2006年 | 72篇 |
2005年 | 76篇 |
2004年 | 113篇 |
2003年 | 99篇 |
2002年 | 73篇 |
2001年 | 46篇 |
2000年 | 39篇 |
1999年 | 38篇 |
1998年 | 24篇 |
1997年 | 23篇 |
1996年 | 20篇 |
1995年 | 16篇 |
1994年 | 16篇 |
1993年 | 17篇 |
1992年 | 33篇 |
1991年 | 27篇 |
1990年 | 19篇 |
1989年 | 18篇 |
1988年 | 19篇 |
1987年 | 15篇 |
1986年 | 25篇 |
1985年 | 18篇 |
1984年 | 12篇 |
1983年 | 6篇 |
1982年 | 13篇 |
1981年 | 13篇 |
1980年 | 11篇 |
1979年 | 6篇 |
1978年 | 9篇 |
1977年 | 7篇 |
1976年 | 6篇 |
1974年 | 5篇 |
1973年 | 4篇 |
1968年 | 5篇 |
排序方式: 共有1602条查询结果,搜索用时 0 毫秒
51.
52.
The gnomefish (Scombrops boops) is a member of the percoid family Scombropidae, which includes a single genus and three to four species worldwide. Since little is known about the ecology of this species, here, sequencing analysis of the cytochrome b gene (1141 bp) in mitochondrial DNA detected 101 haplotypes from 186 individuals of S. boops collected from waters at seven localities around the Japanese archipelago. A single haplotype (Sb2) was the most abundant in the combined populations of S. boops from various localities. Genetic population structure analyses revealed no significant differences among these populations (Fst = - 0.0313-0.0195; Φst = - 0.0505-0.0615) with high haplotype diversity and low nucleotide diversity. This suggests that S. boops around the Japanese archipelago constitutes a single population, and indicates that the genetic structure of this population may be influenced by larval and egg dispersal in association with warm currents. 相似文献
53.
Tomohiro Nishimura Shinya Sato Wittaya Tawong Hiroshi Sakanari Haruo Yamaguchi Masao Adachi 《Journal of phycology》2014,50(3):506-514
A new epiphytic dinoflagellate is described, G ambierdiscus scabrosus sp. nov., from tidal pools and rocky shores along the coastal areas of Japan. Cells are 63.2 ± 5.7 μm in depth, 58.2 ± 5.7 μm in width, and 37.3 ± 3.5 μm in length. The plate formula of G . scabrosus is Po, 4′, 0a, 6′′, 6c, ?s, 5′′′, 0p, and 2′′′′. Morphologically, G . scabrosus resembles G . belizeanus as follows: anterioposteriorly compressed cell shape, narrow 2′′′′ plate, and areolated surface. Despite this similarity, the cells of G . scabrosus can be distinguishable by the presence of the asymmetric shaped 3′′ plate and the rectangular shaped 2′ plate. 相似文献
54.
55.
Takeo Suzuki Haruo Honda Ryoichi Katsumata 《Bioscience, biotechnology, and biochemistry》2013,77(12):2223-2228
Corynebacterium sp. KY 4339, when grown on n-paraffin (a mixture of C–12 to C–14 fractions) as the sole carbon source, produced three kinds of antibacterial compounds which were tentatively named Corynecins. These compounds were isolated by the extraction from the culture broth with ethyl acetate and by the chromatographies on silicic acid and alumina columns. Each component demonstrated some similarity to chloramphenicol on thin-layer chromatogram. Although their biological activities were not so remarkably as that of chloramphenicol, the patterns of antibacterial spectra against gram-positive and gram-negative bacteria resembled to it.For the production of corynecins, n-paraffin was a preferable carbon source. By controlling the pH of the medium in the neutral range and keeping the aeration at a high level during the fermentation, approximately 3 g of corynecins per liter of the medium were produced after 72-hr incubation. 相似文献
56.
57.
Iwao Koyama Haruo Yamagami Toyoyasu Kuwae Munetsugu Kurata 《Prostaglandins & other lipid mediators》1982,23(6):777-785
The release of 6-keto-prostaglandin F1α (6KF1α)_and of thromboxane B2 (TXB2) from cells were investigated using mouse peritoneal exudate cells (PECs) and non-cultured peritoneal macrophages. They were prepared by adhesion to glass dishes and incubated for 1 hr at 37°C in 5% Co2 in air. Both the percentage of spreading macrophages and the release of 6KF1α and TXb2 increased in proportion to the incubation time. 6KF1α and TXB2 were released from the macrophages, not from the non-adherent cells. When PECs were incubated in silicon-coated glass dishes, the spreading of macrophages was hardly detected and lower amounts of 6KF1α and TXB2 were released from these cells compared with cells incubated in non-treated glass dishes. These findings suggest that adhesion with the correlated spreading of macrophages on glass dishes serve as a considerable physical factor for the release of 6KF1α and TXB2. 相似文献
58.
Haruo Ogura Hiroshi Takahashi Kikuko Ohokubo 《Nucleosides, nucleotides & nucleic acids》2013,32(2):147-154
Abstract The reaction of glycosyl isothiocyanates (la, b, c, d, e) with 5,6-diamino-1-3-dimethyluracil gave the respective 1-glycosyl-3-(6-amino-1, 3-dimethyl-2, 4-dioxopyrimidine-5-yl) thioureas (2a, b, c, d, e) in excellent yields. Treatment of these thioureas with NBS afforded the respective 5,7-dioxopyrimido-[5,4-e]-as-triazine glycosides (4a, b, c, d, e) in good yields. 相似文献
59.
Nao Kusuhashi Yukiyasu Tsutsumi Haruo Saegusa Kenji Horie Tadahiro Ikeda Kazumi Yokoyama Kazuyuki Shiraishi 《Proceedings. Biological sciences / The Royal Society》2013,280(1759)
We here describe a new Early Cretaceous (early Albian) eutherian mammal, Sasayamamylos kawaii gen. et sp. nov., from the ‘Lower Formation’ of the Sasayama Group, Hyogo Prefecture, Japan. Sasayamamylos kawaii is characterized by a robust dentary, a distinct angle on the ventral margin of the dentary at the posterior end of the mandibular symphysis, a lower dental formula of 3–4 : 1 : 4 : 3, a robust lower canine, a non-molariform lower ultimate premolar, and a secondarily reduced entoconid on the molars. To date, S. kawaii is the earliest known eutherian mammal possessing only four premolars, which demonstrates that the reduction in the premolar count in eutherians started in the late Early Cretaceous. The occurrence of S. kawaii implies that the relatively rapid diversification of eutherians in the mid-Cretaceous had already started by the early Albian. 相似文献
60.
Yoshitaka Kokusho Haruo Machida Shinjiro Iwasaki 《Bioscience, biotechnology, and biochemistry》2013,77(7):1743-1750
For the production of extracellular lipase by Alcaligenes species No. 679, NaNO3, polyoxyethylene alkyl ether, Fe++, sodium citrate and fructose were found to be effective. The enzyme was prepared by acetone precipitation from the filtrate of the culture broth of this strain. The enzyme was most active at pH 9.0 and 50°C, while 35% of its activity was lost on heat treatment at 60°C for 10 min. Sodium salts of bile acids stimulated the enzyme activity. This lipase could hydrolyse natural fats and oils as well as olive oil. During the hydrolysis of olive oil, monoglyceride was found to accumulate up to 70 mol percent. This lipase possesses special properties similar to those of pancreatic lipase as shown in the comparative experiments. 相似文献