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771.
Michał Panek Mateusz Jonakowski Jan Zioło Tadeusz Pietras Łukasz Wieteska Beata Małachowska Łukasz Mokros Janusz Szemraj Piotr Kuna 《Molecular neurobiology》2017,54(3):1733-1744
Asthma is a chronic inflammatory and heterogeneous disease developing mostly through allergic inflammation, which modifies the expression of various cytokines and neurotrophins. Previous studies suggest the involvement of interleukin (IL)-15 in the regulation of immune response in asthma. Brain-derived neurotrophic factor (BDNF) II plays an important role as a regulator of development and survival of neurons as well as maintenance of their physiological activity. Chronic stress associated with asthma and elevated IL-15 mRNA and BDNFII mRNA levels may affect the mood and a subjective sensation of dyspnoea-inducing anxiety. Psychopathological variables and numerous cytokine/neurotrophin interactions influence the formation of temperament and strategies of coping with stress. The aim of the study was to identify the role of IL-15 mRNA and BDNFII mRNA expressions and their effect on components of temperament and strategies of coping with stress in asthmatics. A total of 352 subjects (176 healthy volunteers and 176 asthmatic patients) participated in the study. The Formal Characteristic of Behaviour-Temperament Inventory (FCB-TI), Coping Inventory for Stressful Situations (CISS), Beck Depression Inventory, State-Trait Anxiety Inventory, and Borg Rating of Perceived Exertion (RPE) Scale were applied in all the subjects. The expression of IL-15 and BDNFII gene was measured using quantitative real-time polymerase chain reaction (qRT-PCR). Different levels of IL-15 and BDNFII expressions between healthy volunteers and patients were revealed in the study. IL-15 enhanced the BDNFII mRNA expression among patients with bronchial asthma. The depression level negatively correlated with the BDNFII mRNA expression. This neurotrophin modified the temperament variable. BDNFII significantly affected (proportional relationship) the level of briskness in asthmatic patients. BDNFII might influence the level and style of coping with stress (emotion-oriented style). This hypothesis requires further studies on protein functional models. The obtained data confirms the role of IL-15 and BDNFII in the pathomechanisms of depression and formation of selected traits defining the temperament in asthmatics. 相似文献
772.
Mating tactics in species with facultative polygyny seem to be very flexible and to depend on local environmental conditions.
We analysed the habitat and population contexts of territorial behaviour, associated with polygyny, in a population of Sedge
Warblers Acrocephalus schoenobaenus inhabiting natural wetlands. Nearly one-third of all breeding males (46 individuals) resumed song after completing their
mating with the first female, in order to attract another one. Resuming males were usually the earliest arrivals. There was
a continuity in the territorial behaviour between resuming song on first territory and polyterritorial behaviour. Fifty-nine
percent of resuming males set up second territories, clearly separated from the first. The second territory was usually located
close to the primary female activity area. The quality of the first and second territories were correlated, with second territories
being significantly inferior. However, their quality was not significantly different from the territories of non-breeding
males. The quality of the second territories was also negatively related to the distance from the first territories. Polyterritorialism
was influenced by population numbers: the higher the number of territorial males, the lower the number of second territories
settled and the lower their average quality. Although the polygyny frequency in the studied population was very low, polyterritorial
males were significantly more likely to be polygynous. We concluded that polygyny frequency can be significantly influenced
by population numbers, which might be one of the main factors responsible for the variability in the mating system in this
species. 相似文献
773.
774.
775.
Tadeusz Penczak Andrzej Kruk Maria Grzybkowska Magorzata Dukowska 《Acta Oecologica》2006,30(3):312-321
The paper assesses the impact of the Jeziorsko dam reservoir on chironomid assemblages and selected environmental factors in the Warta River, Poland, by means of patterns recognized with the self-organizing map (SOM, Kohonen unsupervised artificial neural network). Over 1988–1996, in four annual cycles, a total of 233 monthly samples were collected in a seven order section of the river at two sites: WAA (backwater) located about 2 km upstream from the Jeziorsko Reservoir, and WAB (tailwater) located about 1.5 km downstream from the reservoir's dam. At each site three habitats were selected: H1, H2 and H3 at WAA, and H11, H12 and H13 at WAB. H1 and H11 were located in the depositional area close to the banks, H2 and H12 about 6–7 m towards the mid-river and H3 and H13 in the mid-river. SOM effectively vertically separated H1 and H11 (bank habitats) from H3 and H13 (the mid-river zone of both sites) and H2 (the transition zone of the upstream site). The H12 samples were scattered all over SOM but still exhibited a slight temporal gradient. At the end of the study the water discharge, especially in summers, stabilized at WAB at a level lower than natural and as a result submerged macrophytes appeared at H12 making the abundance of macroinvertebrates increase very quickly. Moreover, a weaker horizontal grouping of samples by season and by site of collection (upstream or downstream from the reservoir) was observed over SOM: 1) bank upstream habitat H1, with hydrological regime resembling natural, was separated from the downstream H11, which enlarged and contracted in response to dam operation, 2) deeper habitats were less dependent on water level and this is why they underwent seasonal fluctuations. To sum up, the deepest habitats were most resistant to water level fluctuations, while the formerly most productive habitat at the tailwater WAB site, H11, became the most negatively impacted. Nevertheless, the reservoir has not negatively influenced chironomid density, because the latter increased closer the mid-river, at H12, where large patches of macrophytes developed. 相似文献
776.
777.
Katarzyna Paszkowska-Szczur Rodney J. Scott Bohdan Górski Cezary Cybulski Grzegorz Kurzawski Dagmara Dymerska Satish Gupta Thierry van de Wetering Bartłomiej Masojć Aniruddh Kashyap Paulina Gapska Tomasz Gromowski Józef Kładny Jan Lubiński Tadeusz Dębniak 《Molecular biology reports》2015,42(3):755-764
778.
This article presents a simple and rapid method for removal of unincorporated label and proteins from DNA sequencing reactions
by using Wizard purification resin. This method can be successfully applied for preparation of end-labeled oligonucleotides
free of unincorporated label, which is important in experiments (including DNA sequencing) when the level of background should
be as low as possible. Also, this method is effective in removal of proteins from DNA sequencing reactions. 相似文献
779.
Specificity of chicken and mammalian transferrins in myogenesis 总被引:1,自引:0,他引:1
Chicken transferrins isolated from eggs, embryo extract, serum or ischiatic-peroneal nerves are able to stimulate incorporation of [3H]thymidine, and promote myogenesis by primary chicken muscle cells in vitro. Mammalian transferrins (bovine, rat, mouse, horse, rabbit, and human) do not promote [3H]thymidine incorporation or myotube development. Comparison of the peptide fragments obtained after chemical or limited proteolytic cleavage demonstrates that the four chicken transferrins are all indistinguishable, but they differ considerably from the mammalian transferrins. The structural differences between chicken and mammalian transferrins probably account for the inability of mammalian transferrins to act as mitogens for, and to support myogenesis of, primary chicken muscle cells. 相似文献
780.