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11.
The Value of Artificial Stimuli in Behavioral Research: Making the Case for Egg Rejection Studies in Avian Brood Parasitism 下载免费PDF全文
Márk E. Hauber Lainga Tong Miklós Bán Rebecca Croston Tomáš Grim Geoffrey I. N. Waterhouse Matthew D. Shawkey Andrew B. Barron Csaba Moskát 《Ethology : formerly Zeitschrift fur Tierpsychologie》2015,121(6):521-528
Experimentation is at the heart of classical and modern behavioral ecology research. The manipulation of natural cues allows us to establish causation between aspects of the environment, both internal and external to organisms, and their effects on animals' behaviors. In recognition systems research, including the quest to understand the coevolution of sensory cues and decision rules underlying the rejection of foreign eggs by hosts of avian brood parasites, artificial stimuli have been used extensively, but not without controversy. In response to repeated criticism about the value of artificial stimuli, we describe four potential benefits of using them in egg recognition research, two each at the proximate and ultimate levels of analysis: (1) the standardization of stimuli for developmental studies and (2) the disassociation of correlated traits of egg phenotypes used for sensory discrimination, as well as (3) the estimation of the strength of selection on parasitic egg mimicry and (4) the establishment of the evolved limits of sensory and cognitive plasticity. We also highlight constraints of the artificial stimulus approach and provide a specific test of whether responses to artificial cues can accurately predict responses to natural cues. Artificial stimuli have a general value in ethological research beyond research in brood parasitism and may be especially critical in field studies involving the manipulation of a single parameter, where other, confounding variables are difficult or impossible to control experimentally or statistically. 相似文献
12.
Ming‐Dong Zhang Amit Zeisel André Calas Marc Landry Matthew Fuszard Sally L Shirran Robert Schnell Árpád Dobolyi Márk Oláh Lauren Spence Jan Mulder Henrik Martens Miklós Palkovits Mathias Uhlen Harald H Sitte Catherine H Botting Ludwig Wagner Sten Linnarsson Tibor Harkany 《The EMBO journal》2015,34(1):36-54
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Attila Molvarec Zoltán Derzsy Judit Kocsis Tamás Bőze Bálint Nagy Krisztián Balogh Veronika Makó László Cervenak Miklós Mézes István Karádi Zoltán Prohászka János Rigó Jr 《Cell stress & chaperones》2009,14(5):491-498
It has been previously reported that circulating anti-heat-shock-protein (Hsp) antibody levels are elevated in cardiovascular
disorders. The aim of the present study was to determine circulating antihuman Hsp60, antimycobacterial Hsp65, and antihuman
Hsp70 antibody levels in healthy pregnant women and preeclamptic patients and to investigate their relationship to the clinical
characteristics of the study subjects, as well as to the markers of inflammation (C-reactive protein (CRP)), endothelial activation
(von Willebrand factor antigen), or endothelial injury (fibronectin), oxidative stress (malondialdehyde) and to serum Hsp70
levels. Ninety-three preeclamptic patients and 127 normotensive healthy pregnant women were involved in this case control
study. Serum anti-Hsp60, anti-Hsp65, anti-Hsp70, and Hsp70 levels were measured with enzyme-linked immunosorbent assay (ELISA).
Serum CRP levels were determined by an autoanalyzer using the manufacturer’s kit. Plasma von Willebrand factor antigen levels
were quantified by ELISA, while plasma fibronectin concentration by nephelometry. Plasma malondialdehyde levels were measured
by the thiobarbituric-acid-based colorimetric assay. For statistical analyses, nonparametric methods were applied. Anti-Hsp60,
anti-Hsp65, and anti-Hsp70 antibodies were detected in all of our serum samples. There were no significant differences in
serum anti-Hsp60, anti-Hsp65, and anti-Hsp70 antibody levels between the control and preeclamptic groups. Serum levels of
Hsp70 and CRP, as well as plasma levels of VWF antigen, fibronectin, and malondialdehyde, were significantly higher in preeclamptic
patients than in normotensive healthy pregnant women. Serum anti-Hsp60 antibody levels showed significant correlations with
serum anti-Hsp65 antibody levels both in the control and the preeclamptic groups (Spearman R = 0.55 and 0.59; p < 0.001, respectively). However, no other relationship was found between clinical features (maternal age, smoking status,
parity, body mass index, gestational age at blood draw, systolic and diastolic blood pressure, gestational age at delivery,
and fetal birth weight) and measured laboratory parameters of the study subjects and serum anti-Hsp antibody levels in either
study group. In conclusion, anti-Hsp60 and anti-Hsp70 antibodies as naturally occurring autoantibodies are present in the
peripheral circulation of healthy pregnant women. Nevertheless, humoral immunity against heat shock proteins was not associated
with preeclampsia. Further studies are warranted to explore the role of heat shock proteins and immune reactivity to them
in the immunobiology of normal pregnancy and preeclampsia. 相似文献
15.
Ferenc Faigl Bernadett Vas‐Feldhoffer Veronika Kudar Mátyás Czugler Krisztina Pál Miklós Kubinyi 《Chirality》2009,21(10):905-910
Site selective mono‐ and dimetalation methods have been developed for the functionalization of 1‐[(1,1′‐biphenyl)‐2‐yl]‐1H‐pyrrole. Optical resolution of the prepared 1‐[(3‐carboxy‐1,1′‐biphenyl)‐2‐yl]pyrrole‐2‐carboxylic acid provided new atropisomeric 1‐arylpyrrole derivatives. The absolute configuration of the pure dicarboxylic acid enantiomers was determined by single crystal X‐ray diffraction and CD spectroscopy. Chirality 2009. © 2009 Wiley‐Liss, Inc. 相似文献
16.
In a river, the flow directly affects the physical and chemical properties of its water, with further consequences for aquatic
biota. Land use practices and vegetation cover play a significant role in the water cycle. The wide-spread perception of forest
cover, in terms of hydrology is that forests may reduce water runoff: although in rare instances the contrary has been reported.
Water runoff varies seasonally and depends on the forest tree species. By no means can it be considered constant over large
expanses of area or for various rainfall patterns. In this paper, the results of a long-term hydrological survey conducted
in two experimental microbasins (operated by the Institute of Hydrology SAS, IH SAS) with different land use practices are
presented. The Rybárik microbasin (0.119 km2) is dominated by row crop production. The basin was 70% cultivated by the state farm and 30% by a private farm. The Lesny
microbasin (0.086 km2) is covered by a deciduous hornbeam regrowth forest (Carpinus betulus). The analysis revealed that the difference in the
runoff from the forest and the agricultural land increases with increasing precipitation; however, at some point (extreme
precipitations with low probability) the runoff from these basins is nearly equal. 相似文献
17.
Mark H. Doolittle Saskia B. Neher Osnat Ben-Zeev Jo Ling-liao Ciara M. Gallagher Maryam Hosseini Fen Yin Howard Wong Peter Walter Mikl��s P��terfy 《The Journal of biological chemistry》2009,284(48):33623-33633
Lipase maturation factor 1 (LMF1) is predicted to be a polytopic protein localized to the endoplasmic reticulum (ER) membrane. It functions in the post-translational attainment of enzyme activity for both lipoprotein lipase and hepatic lipase. By using transmembrane prediction methods in mouse and human orthologs, models of LMF1 topology were constructed and tested experimentally. Employing a tagging strategy that used insertion of ectopic glycan attachment sites and terminal fusions of green fluorescent protein, we established a five-transmembrane model, thus dividing LMF1 into six domains. Three domains were found to face the cytoplasm (the amino-terminal domain and loops B and D), and the other half was oriented to the ER lumen (loops A and C and the carboxyl-terminal domain). This representative model shows the arrangement of an evolutionarily conserved domain within LMF1 (DUF1222) that is essential to lipase maturation. DUF1222 comprises four of the six domains, with the two largest ones facing the ER lumen. We showed for the first time, using several naturally occurring variants featuring DUF1222 truncations, that Lmf1 interacts physically with lipoprotein lipase and hepatic lipase and localizes the lipase interaction site to loop C within DUF1222. We discuss the implication of our results with regard to lipase maturation and DUF1222 domain structure. 相似文献
18.
Newly synthesized lipoprotein lipase (LPL) and related members of the lipase gene family require an endoplasmic reticulum maturation factor for attainment of enzyme activity. This factor has been identified as lipase maturation factor 1 (Lmf1), and mutations affecting its function and/or expression result in combined lipase deficiency (cld) and hypertriglyceridemia. To assess the functional impact of Lmf1 sequence variations, both naturally occurring and induced, we report the development of a cell-based assay using LPL activity as a quantitative reporter of Lmf1 function. The assay uses a cell line homozygous for the cld mutation, which renders endogenous Lmf1 nonfunctional. LPL transfected into the mutant cld cell line fails to attain activity; however, cotransfection of LPL with wild-type Lmf1 restores its ability to support normal lipase maturation. In this report, we describe optimized conditions that ensure the detection of a complete range of Lmf1 function (full, partial, or complete loss of function) using LPL activity as the quantitative reporter. To illustrate the dynamic range of the assay, we tested several novel mutations in mouse Lmf1. Our results demonstrate the ability of the assay to detect and analyze Lmf1 mutations having a wide range of effects on Lmf1 function and protein expression. 相似文献
19.
The secure base and safe haven effects of the attachment figure are central features of the human attachment theory. Recently, conclusive evidence for human analogue attachment behaviours in dogs has been provided, however, the owner’s security-providing role in danger has not been directly supported. We investigated the relationship between the behavioural and cardiac response in dogs (N = 30) while being approached by a threatening stranger in separation vs. in the presence of the owner, presented in a balanced order. Non-invasive telemetric measures of heart rate (HR) and heart rate variability (HRV) data during the threatening approaches was compared to periods before and after the encounters. Dogs that showed distress vocalisation during separation (N = 18) and that growled or barked at the stranger during the threatening approach (N = 17) were defined as behaviourally reactive in the given situation. While characteristic stress vocalisations were emitted during separations, the absence of the owner did not have an effect on dogs’ mean HR, but significantly increased the HRV. The threatening approach increased dogs’ mean HR, with a parallel decrease in the HRV, particularly in dogs that were behaviourally reactive to the encounter. Importantly, the HR increase was significantly less pronounced when dogs faced the stranger in the presence of the owner. Moreover, the test order, whether the dog encountered the stranger first with or without its owner, also proved important: HR increase associated with the encounter in separation seemed to be attenuated in dogs that faced the stranger first in the presence of their owner. We provided evidence for human analogue safe haven effect of the owner in a potentially dangerous situation. Similarly to parents of infants, owners can provide a buffer against stress in dogs, which can even reduce the effect of a subsequent encounter with the same threatening stimuli later when the owner is not present. 相似文献
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