全文获取类型
收费全文 | 2566篇 |
免费 | 250篇 |
出版年
2023年 | 6篇 |
2022年 | 7篇 |
2021年 | 50篇 |
2020年 | 29篇 |
2019年 | 33篇 |
2018年 | 41篇 |
2017年 | 38篇 |
2016年 | 79篇 |
2015年 | 118篇 |
2014年 | 150篇 |
2013年 | 172篇 |
2012年 | 219篇 |
2011年 | 212篇 |
2010年 | 146篇 |
2009年 | 113篇 |
2008年 | 185篇 |
2007年 | 166篇 |
2006年 | 156篇 |
2005年 | 127篇 |
2004年 | 118篇 |
2003年 | 107篇 |
2002年 | 108篇 |
2001年 | 39篇 |
2000年 | 40篇 |
1999年 | 33篇 |
1998年 | 33篇 |
1997年 | 30篇 |
1996年 | 26篇 |
1995年 | 19篇 |
1994年 | 17篇 |
1993年 | 14篇 |
1992年 | 9篇 |
1991年 | 12篇 |
1990年 | 15篇 |
1989年 | 14篇 |
1988年 | 14篇 |
1987年 | 14篇 |
1986年 | 10篇 |
1985年 | 6篇 |
1984年 | 10篇 |
1983年 | 5篇 |
1982年 | 7篇 |
1981年 | 11篇 |
1980年 | 6篇 |
1979年 | 6篇 |
1977年 | 5篇 |
1976年 | 5篇 |
1974年 | 4篇 |
1973年 | 7篇 |
1968年 | 3篇 |
排序方式: 共有2816条查询结果,搜索用时 15 毫秒
1.
J. Dierschke T. Krüger F. Hüttmann F. Bairlein Kerstin Müller G. Scheiffarth H. -W. Helb W. Irsch W. Lantermann B. Haubitz W. Winkel und J. Haffer 《Journal of Ornithology》2003,144(4):484-498
Ohne Zusammenfassung 相似文献
2.
Anna Nilsson Thomas E. Fehniger Lena Gustavsson Malin Andersson Kerstin Kenne Gy?rgy Marko-Varga Per E. Andrén 《PloS one》2010,5(7)
Readouts that define the physiological distributions of drugs in tissues are an unmet challenge and at best imprecise, but are needed in order to understand both the pharmacokinetic and pharmacodynamic properties associated with efficacy. Here we demonstrate that it is feasible to follow the in vivo transport of unlabeled drugs within specific organ and tissue compartments on a platform that applies MALDI imaging mass spectrometry to tissue sections characterized with high definition histology. We have tracked and quantified the distribution of an inhaled reference compound, tiotropium, within the lungs of dosed rats, using systematic point by point MS and MS/MS sampling at 200 µm intervals. By comparing drug ion distribution patterns in adjacent tissue sections, we observed that within 15 min following exposure, tiotropium parent MS ions (mass-to-charge; m/z 392.1) and fragmented daughter MS/MS ions (m/z 170.1 and 152.1) were dispersed in a concentration gradient (80 fmol-5 pmol) away from the central airways into the lung parenchyma and pleura. These drug levels agreed well with amounts detected in lung compartments by chemical extraction. Moreover, the simultaneous global definition of molecular ion signatures localized within 2-D tissue space provides accurate assignment of ion identities within histological landmarks, providing context to dynamic biological processes occurring at sites of drug presence. Our results highlight an important emerging technology allowing specific high resolution identification of unlabeled drugs at sites of in vivo uptake and retention. 相似文献
3.
Sandra Danner Christiane Kirchhoff Richard Ivell 《Reproductive biology and endocrinology : RB&E》2009,7(1):67-14
Background
Post-meiotically expressed genes in the testis are essential for the proper progression of spermatogenesis, and yet, aside from the construction of individual transgenic mice using specific promoters to drive reporter plasmids, there are only very limited possibilities for relevant and quantitative analysis of gene promoters. This is due to the special nature of post-meiotic haploid cells, which to date are not represented in any appropriate cell-lines. This article reports the development of novel methodology using isolated and cultured rat seminiferous tubules in a multiwell format, into which promoter-reporter constructs can be introduced by a combination of microinjection and electroporation. 相似文献4.
Lars Svennerholm Pam Fredman Birgitta Jungbjer Jan-Eric Månsson Britt-Marie Rynmark Kerstin Boström Bengt Hagberg Lars Norén Pirkko Santavuori 《Journal of neurochemistry》1987,49(6):1772-1783
Lipid composition was studied on cerebral tissue from nine children who had died of a progressive encephalopathy called the infantile form of neuronal ceroid lipofuscinosis (INCL) or polyunsaturated fatty acid lipidosis (PFAL). In the terminal stage of the disease, the concentrations of all lipid classes were found to be significantly reduced in the cerebral and cerebellar cortex and white matter. The concentration of gangliosides of the cerebral cortex was 15% and that of cerebrosides (galactosylceramide) in white matter 0.2-5% of the normal values for the children's ages. The reduction of gangliosides mainly affected those of the gangliotetraose series, particularly GD1a. The fatty acids of the linolenic acid series were strongly reduced in ethanolamine and serine phosphoglycerides. A very large increase up to 100-fold of oligoglycosphingolipids of the globo series and two fucose-containing lipids of the neolacto series was found in the forebrain of the three advanced cases examined. The brain tissue also contained very high concentrations of mono-, di-, and trisialogangliosides of the lacto and neolacto series, gangliosides with type 1 chain dominating. The structures of the gangliosides were tentatively identified by gas chromatography-mass spectrometry and monoclonal antibodies with carefully determined epitope specificity. The gangliosides and neutral glycosphingolipids had very similar fatty acid composition, consisting of about 40% stearic acid and 40% C24-acids. 相似文献
5.
6.
7.
8.
Ubiquitin genes in trypanosomatidae 总被引:11,自引:0,他引:11
L V Kirchhoff K S Kim D M Engman J E Donelson 《The Journal of biological chemistry》1988,263(25):12698-12704
9.
Replication of bovine papillomavirus vectors in murine cells 总被引:2,自引:0,他引:2
Margareta Waldenstrm Kerstin Schenstrm Kerstin Sollerbrant Lennart Hansson 《Gene》1992,120(2):175-181
10.
Kerstin Huss-Danell 《Plant and Soil》1986,91(1):43-49
Summary A pot experiment withAlnus incana (L.) Moench growing in sand was set up to compare the amounts of nitrogen released from plants shoot litter with that released below ground as root litter and/or root exudation. No nitrogen fixation by free-living microorganisms was found in the sand and the increased nitrogen content of the plant + soil system was therefore due to nitrogen fixation byFrankia in the alder root-nodules. Most of the nitrogen released from the plants was in the nitrogen-rich leaf and other shoot litter. Only small amounts of nitrogen were found in the drainage water from the pots and were recorded as increased nitrogen content of the sand. 相似文献