全文获取类型
收费全文 | 425篇 |
免费 | 50篇 |
专业分类
475篇 |
出版年
2022年 | 5篇 |
2021年 | 16篇 |
2019年 | 5篇 |
2018年 | 4篇 |
2017年 | 6篇 |
2016年 | 6篇 |
2015年 | 16篇 |
2014年 | 13篇 |
2013年 | 19篇 |
2012年 | 25篇 |
2011年 | 20篇 |
2010年 | 11篇 |
2009年 | 13篇 |
2008年 | 16篇 |
2007年 | 11篇 |
2006年 | 11篇 |
2005年 | 17篇 |
2004年 | 15篇 |
2003年 | 13篇 |
2002年 | 15篇 |
2001年 | 17篇 |
2000年 | 16篇 |
1999年 | 7篇 |
1998年 | 4篇 |
1997年 | 6篇 |
1996年 | 6篇 |
1993年 | 3篇 |
1992年 | 8篇 |
1991年 | 3篇 |
1990年 | 5篇 |
1989年 | 7篇 |
1988年 | 4篇 |
1987年 | 6篇 |
1986年 | 7篇 |
1985年 | 6篇 |
1984年 | 4篇 |
1983年 | 5篇 |
1982年 | 8篇 |
1981年 | 6篇 |
1979年 | 4篇 |
1978年 | 5篇 |
1977年 | 7篇 |
1970年 | 3篇 |
1969年 | 7篇 |
1968年 | 3篇 |
1942年 | 3篇 |
1941年 | 6篇 |
1940年 | 6篇 |
1939年 | 7篇 |
1938年 | 3篇 |
排序方式: 共有475条查询结果,搜索用时 0 毫秒
71.
A virus inhibiting protein (VI) was isolated from spinach (Spinacia oleracea L.). The VI inhibited infections of test plants with plus- and minus-strand RNA viruses. Inoculation of both local lesion and systemic hosts with TMV in the presence of varying amounts of the VI resulted in typical dose response curves for the number of local lesions or the amount of virus respectively. The lowest concentration of VI leading to a significant reduction in the number of local lesions was 0.06 μg/ml. The VI was found to inhibit local lesion formation only when applied within 2–3 h p.i. but still reduced the number of local lesions when applied up to 9 h prior to virus inoculation. The antiviral activity could be attributed to a protein of molecular weight 29,000 dalton with an isoelectric point of 10.3. Its activity was destroyed by heating for 30 min to 70°C. These characteristics resemble those of other virus inhibiting proteins described for members of the order Caryophyllales such as the Phytolacca inhibitor against which a serological relationship was obtained. 相似文献
72.
73.
Herren T.; Bartsch P.; Haeberli A.; Straub P. W. 《Journal of applied physiology》1992,73(6):2499-2504
74.
H Schulte-Wissermann E Straub P J Funke 《Virchows Archiv. B, Cell pathology including molecular pathology》1977,23(2):163-173
HgC12-induced renal tubular lesions in the rat present histochemically with a transitory decrease of alkaline phosphatase, adenosinetriphosphatase (ATPase), and leucine-aminopeptidase activity. The toxic alterations of enzyme activity were more pronounced in the pars recta of the proximal tubule and in the loop of Henle, as compared with the tubulus contortus I. L-thyroxine treatment leads to an accelerated reversal of that enzymatic defect, followinga characteristic pattern, and to a differentiating increase of acid phosphatase and ATPase activity in certain parts of the normal renal tubule. The observations are discussed with reference to the specific mode of action of sublimate and l-thyroxine upon the tubular enzymes and to the well-known metabolic and functional influences of thyroid hormone on the kidney. 相似文献
75.
The regulation of penicillinase synthesis 总被引:5,自引:0,他引:5
76.
Meyer Engel E. Stein Lüers P. Sabaneeff Lein G. Kretschmer M. Zwintzscher H. J. Müller H. Nachtsheim St. Reichmuth Wulff J. Straub I. Grebenščikov K. Paech M. Oesterlin Dielzel U. Ruge F. Moewus K. Peters Erb.-Lanz G. Bosian W. Rothmaler 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1951,21(4-5):153-160
Ohne Zusammenfassung 相似文献
77.
C. Harte H. Nachtsheim F. Brabec Kaplan W. Halbsguth I. Straub B. Haccius Lein R. Hesse A. Lang H. Marquardt J. Dembowski Eifrig M. Zwintzscher J. Krause J. Dembowski W. Baumeister 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1952,22(1-2):60-64
Ohne Zusammenfassung 相似文献
78.
79.
Prolyl hydroxylase inhibitors delay neuronal cell death caused by trophic factor deprivation 总被引:2,自引:0,他引:2
Nerve growth factor (NGF) serves a critical survival-promoting function for developing sympathetic neurons. Following removal of NGF, sympathetic neurons undergo apoptosis characterized by the activation of c-Jun N-terminal kinases (JNKs), up-regulation of BH3-only proteins including BcL-2-interacting mediator of cell death (BIM)EL , release of cytochrome c from mitochondria, and activation of caspases. Here we show that two small-molecule prolyl hydroxylase inhibitors frequently used to activate hypoxia-inducible factor (HIF) – ethyl 3,4-dihydroxybenzoic acid (DHB) and dimethyloxalylglycine (DMOG) – can inhibit apoptosis caused by trophic factor deprivation. Both DHB and DMOG blocked the release of cytochrome c from mitochondria after NGF withdrawal, whereas only DHB blocked c-Jun up-regulation and phosphorylation. DHB, but not DMOG, also attenuated the induction of BIMEL in NGF-deprived neurons, suggesting a possible mechanism whereby DHB could inhibit cytochrome c release. DMOG, on the other hand, was substantially more effective at stabilizing HIF-2α and inducing expression of the HIF target gene hexokinase 2 than was DHB. Thus, while HIF prolyl hydroxylase inhibitors can delay cell death in NGF-deprived neurons, they do so through distinct mechanisms that, at least in the case of DHB, are partly independent of HIF stabilization. 相似文献
80.
Leu BM Zhang Y Bu L Straub JE Zhao J Sturhahn W Alp EE Sage JT 《Biophysical journal》2008,95(12):5874-5889
Conformational flexibility is essential to the functional behavior of proteins. We use an effective force constant introduced by Zaccai, the resilience, to quantify this flexibility. Site-selective experimental and computational methods allow us to determine the resilience of heme protein active sites. The vibrational density of states of the heme Fe determined using nuclear resonance vibrational spectroscopy provides a direct experimental measure of the resilience of the Fe environment, which we compare quantitatively with values derived from the temperature dependence of atomic mean-squared displacements in molecular dynamics simulations. Vibrational normal modes in the THz frequency range dominate the resilience. Both experimental and computational methods find a higher resilience for cytochrome c than for myoglobin, which we attribute to the increased number of covalent links to the peptide in the former protein. For myoglobin, the resilience of the iron environment is larger than the average resilience previously determined for hydrogen sites using neutron scattering. Experimental results suggest a slightly reduced resilience for cytochrome c upon oxidation, although the change is smaller than reported in previous Mössbauer investigations on a bacterial cytochrome c, and is not reproduced by the simulations. Oxidation state also has no significant influence on the compressibility calculated for cyt c, although a slightly larger compressibility is predicted for myoglobin. 相似文献