全文获取类型
收费全文 | 385篇 |
免费 | 17篇 |
出版年
2022年 | 2篇 |
2021年 | 2篇 |
2020年 | 2篇 |
2018年 | 3篇 |
2017年 | 3篇 |
2016年 | 6篇 |
2015年 | 13篇 |
2014年 | 10篇 |
2013年 | 12篇 |
2012年 | 12篇 |
2011年 | 16篇 |
2010年 | 11篇 |
2009年 | 15篇 |
2008年 | 21篇 |
2007年 | 24篇 |
2006年 | 23篇 |
2005年 | 18篇 |
2004年 | 14篇 |
2003年 | 11篇 |
2002年 | 12篇 |
2001年 | 17篇 |
2000年 | 9篇 |
1999年 | 16篇 |
1998年 | 9篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1995年 | 7篇 |
1994年 | 5篇 |
1993年 | 4篇 |
1992年 | 8篇 |
1991年 | 4篇 |
1990年 | 8篇 |
1989年 | 5篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1985年 | 3篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1979年 | 4篇 |
1978年 | 5篇 |
1977年 | 4篇 |
1976年 | 2篇 |
1975年 | 5篇 |
1974年 | 3篇 |
1973年 | 9篇 |
1971年 | 2篇 |
1968年 | 3篇 |
1965年 | 4篇 |
排序方式: 共有402条查询结果,搜索用时 15 毫秒
391.
R Dalla Valle D Guttullo G Vacca 《Bollettino della Società italiana di biologia sperimentale》1979,55(17):1700-1706
Sometimes a common probe of an electromagnetic flowmeter cannot be chronically placed around the aorta in the dog because its weight and shape can induce vascular injuries. Moreover it may occur that the record is disturbed by the movements of the probe around the vessel. The authors describe a new type probe that is capable to produce a reliable signal of the aortic blood flow, in spite of a reduced structure of its components. Obviously, such a signal, which is greater that the one produced by a coronary blood flow probe, must be properly amplified. 相似文献
392.
393.
Cutaneous melanin in formol fixed skin and adrenochrome in dichromate fixed monkey adrenal after adequate bisulfite or dithonite reduction were found to give definite azo coupling reactions. Weaker reactions were obtained on unreduced material, and these disappeared on ferric chloride oxidation. Both cutaneous melanin and adrenochrome appear to exist in a quinhydrone status. Prolongation of dichromate treatment weakens or abolishes azo coupling capacity of adrenochrome. The findings support the concept of quinonization and reduction to prevent and restore azo coupling of enterochromaffin cells and noradrenaline islets of the adrenal. The most effective diazos for melanin were p-nitrodiazobenzene, fast black K and the diazosulfanilic acid, pH 1 pyronin B procedure, for adrenochrome. Diazosafranin and 2-chloro-4-nitrodiazobenzene were also useful. Blue and violet coupling products from toluidine blue and methylene violet RR fail to yield sufficient contrast to be convincing. 相似文献
394.
395.
396.
The undesirable PAS reactivity of cytoplasmic aldehydes after dichromate fixation can be suppressed without affecting selective staining by lowering the pH of Lillie's Cold Schiff reagent to 1.5. Alternatively, dilution of pH 2.2 Cold Schiff reagent with distilled water (1:2) is recommended. Hydrogen ion concentration and dissociation effect the rate of color formation in various PAS positive sites differentially with respect to the time of incubation in Schiff reagent. Based on the experiments, aldehydes exposed in different tissue components appear to be chemically distinct and separable depending on the rate of color formation and duration of incubation in Schiff reagent. 相似文献
397.
398.
Mariella Nieddu Roberto Mezzanotte Giuseppina Pichiri Pier Paolo Coni Gian Luca Dedola Maria Luisa Dettori Michele Pazzola Giuseppe Massimo Vacca Renato Robledo 《Genetics and molecular biology》2015,38(4):513-518
Two clones, Bt1 from Bos taurus and Om1 from Ovis orientalis
musimon, were used as probes for hybridization on genomic DNA and on
metaphase chromosomes in members of Bovini and Caprini tribes. Bt1 and Om1 are
sequences respectively belonging to the 1.715 and 1.714 DNA satellite I families.
Southern blots and fluorescence in situ hybridization experiments
showed completely coherent results: the Bovini probe Bt1 hybridized only to members
of the Bovini tribe and not to members of Caprini. Likewise, the Caprini probe Om1
hybridized only to members of the Caprini tribe and not to members of Bovini.
Hybridization signals were detected in the heterochromatic regions of every
acrocentric autosome, except for two pairs of autosomes from Capra
hircus that did not show hybridization to probe Om1. No signal was
detected on X and Y chromosomes or on bi-armed autosomes. Remarkably, probe Om1
showed almost 100% homology with a bacterial sequence reported in
Helicobacter pylori. 相似文献
399.
Susanna Amadio Fabrizio Vacca Alessandro Martorana Giuseppe Sancesario Cinzia Volonté 《BMC developmental biology》2007,7(1):77
Background
In the CNS, several P2 receptors for extracellular nucleotides are identified on neurons and glial cells to participate to neuron-neuron, glia-glia and glia-neuron communication. 相似文献400.
JP Reyes A Huanosta-Gutiérrez A López-Rodríguez A Martínez-Torres 《Channels (Austin, Tex.)》2015,9(2):88-95
We studied the effects of mutations of positively charged amino acid residues in the pore of X. tropicalis TMEM16A calcium-activated chloride channels: K613E, K628E, K630E; R646E and R761E. The activation and deactivation kinetics were not affected, and only K613E showed a lower current density. K628E and R761E affect anion selectivity without affecting Na+ permeation, whereas K613E, R646E and the double mutant K613E + R646E affect anion selectivity and permeability to Na+. Furthermore, altered blockade by the chloride channel blockers anthracene-9-carboxylic acid (A-9-C), 4, 4''-Diisothiocyano-2,2''-stilbenedisulfonic acid (DIDS) and T16inh-A01 was observed. These results suggest the existence of 2 binding sites for anions within the pore at electrical distances of 0.3 and 0.5. These sites are also relevant for anion permeation and blockade. 相似文献