全文获取类型
收费全文 | 7978篇 |
免费 | 514篇 |
出版年
2023年 | 76篇 |
2021年 | 139篇 |
2020年 | 122篇 |
2019年 | 140篇 |
2018年 | 341篇 |
2017年 | 295篇 |
2016年 | 359篇 |
2015年 | 305篇 |
2014年 | 364篇 |
2013年 | 596篇 |
2012年 | 619篇 |
2011年 | 606篇 |
2010年 | 419篇 |
2009年 | 312篇 |
2008年 | 223篇 |
2007年 | 202篇 |
2006年 | 225篇 |
2005年 | 103篇 |
2004年 | 97篇 |
2003年 | 94篇 |
2002年 | 67篇 |
2001年 | 103篇 |
2000年 | 106篇 |
1999年 | 124篇 |
1998年 | 92篇 |
1997年 | 90篇 |
1996年 | 82篇 |
1995年 | 97篇 |
1994年 | 90篇 |
1993年 | 63篇 |
1992年 | 74篇 |
1991年 | 83篇 |
1990年 | 58篇 |
1989年 | 71篇 |
1988年 | 52篇 |
1987年 | 69篇 |
1986年 | 56篇 |
1985年 | 76篇 |
1984年 | 62篇 |
1983年 | 75篇 |
1982年 | 67篇 |
1981年 | 84篇 |
1980年 | 57篇 |
1979年 | 77篇 |
1978年 | 60篇 |
1977年 | 68篇 |
1975年 | 52篇 |
1974年 | 55篇 |
1970年 | 53篇 |
1969年 | 61篇 |
排序方式: 共有8492条查询结果,搜索用时 78 毫秒
81.
Labuctril 25 (3,5-dibromo-4-hydroxybenzonitrile, LAB) at concentrations up to 100μg/mL inhibits effectively growth, morphology, and pigmentation of most soil streptomycete isolates grown under laboratory conditions. Oxytril CM (OXT), Basagran (BAS) and Faneron 50 WP (FAN) applied at the same concentrations had no detectable effect on growth of substrate mycelium but suppressed both aerial mycelium and pigment formation, the effectivity decreasing in the order OXT—BAS—FAN. The LAB-sensitivity of mutant strains was markedly higher as compared with that of the soil isolates. A wild strain resistant to 100–400μg of LAB per mL (depending on the medium composition) was isolated. It was capable of supporting the growth and development of sensitive strains on the LAB-containing medium. A stimulatory effect of low doses of LAB (10–20μg/mL) on the antibiotic activity of streptomycetes was observed. 相似文献
82.
83.
Vera Hadačová Květa Vacková Eva Klozová M. Kutáček Květa Pitterová 《Biologia Plantarum》1983,25(3):209-215
In partly purified protein complexes obtained from 22 species of theAllium genus and 6 cultivars ofAllium cepa the activity of cholinesterases was detected and measured using the method of Ellman et al. The degree of its inhibition with 10-4 M neostigmine was also tested. It was found that the activity of cholinesterase differed in individual species up to two hundred times, while the differences in the inhibitory activity of 10-4 M neostigmine occurred only in a few cases. Individual sections and cultivars could not be characterized on the basis of the differences in the activities of the cholinesterases. Of all the sections that ofPhyllodolon shows the highest average activity. In the case of the tested cultivars distinctly the lowest activity was observed in cv. Kastická. The values of the enzymatic activity measured by Ellman’s method in this plant material include the activity of specific and unspecific cholinesterases and the part uninhibitable by neostigmine. 相似文献
84.
85.
Jana Pospíšilová Jiřina Slavíkovà J. Tupý Ingrid Tiohá T. Gichner 《Biologia Plantarum》1983,25(3):237-240
86.
87.
Chromosome counts of the following 30 taxa (106 populations) are given:Betonica officinalis (2n=16);Bidens frondosus (2n=48);Calamagrostis arundinacea (2n=28+0–2B);Dianthus carthusianorum subsp.latifolius (2n=30);Festuca gigantea (2n=42, 42+2B);Hypericum perforatum (2n=32);Koeleria macrantha (2n=28);Kohlrauschia prolifera (2n=30);Lilium martagon (2n=24+0–2B);Melica ciliata (2n=18);Poa remota (2n=14);Ranunculus polyanthemos (2n=16);R. sardous subsp.sardous (2n=16);Roegneria canina (2n=28+0–1B);Rudbeckia laciniata (2n=76);Scabiosa canescens (2n=16);Serratula tinctoria (2n=22);Seseli elatum subsp.heterophyllum var.beckii (2n=18);S. hippomarathrum (2n=20);Thlaspicaerulescens caerulescens subsp.tatrense (2n=14);Trifolium alpestre (2n=16);T. avense (2n=14);T. medium (2n=79, 80+0–2B, 82);T. rubens (2n=16);Veronica officinalis subsp. alpestris (2n=36);Vincetoxicum hirundinaria (2n=22);Vulpia bromoides (2n=14);Zerna benekenii (2n=28)Z. monoclada (2n=28+0–8B);Z. ramosa (2n=42). Remarks on taxonomy, nomenclature and chorology for some of these taxa are given. 相似文献
88.
89.
90.
The preparative method of polyacrylamide gel electrophoresis was adapted for purification and characterization of isotopically labeled L-cell interferons. Re-covery of interferon activity was quantitative, and purification and resolution were comparable to those obtained by analytical polyacrylamide gel electrophoresis. Ultimate specific activities attainable ranged from 2 x 10(6) to 3 x 10(6) international units per mg of protein. 相似文献