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101.
To determine the effect of prenatal lead exposure on brain monoaminergic systems, pregnant rats were given tap water containing
250 ppm lead acetate, for the duration of pregnancy, while tap water without lead (Pb2+) was substituted at birth. Control rats were derived from dams that consumed tap water during pregnancy, and had no exposure
to lead afterwards. At 12 weeks after birth, Pb2+ content of brain cortex was increased 3- to 4-fold (P < 0.05). At this time the endogenous striatal levels of 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid were
19% lower in Pb2+ exposed rats (P < 0.05), while there was no change in the striatal level of dopamine (DA), noradrenaline, 3,4-dihydroxyphenylglycol, serotonin
(5-HT) and 5-hydroxyindoleacetic acid (HPLC/ED). Also there was no change in these monoamines and metabolites in the prefrontal
cortex of Pb2+ exposed rats. However, turnover of 5-HT in prefrontal cortex, as indicated by 5-hydroxytryptophan accumulation 30 min after
acute treatment with the decarboxylase inhibitor NSD-1015 (100 mg/kg IP), was lower in the Pb2+ exposed rats. In the striatum AMPH-induced (1 mg/kg IP) turnover of DA, evidenced as L-DOPA accumulation after NSD-1015,
was increased to a lesser extent in the Pb2+ exposed rats (P < 0.05). The nitric oxide synthase inhibitor 7-nitroindazole (10 mg/kg IP) attenuated the latter effect, indicating that
neuronal NO mediates this AMPH effect, at least in part. Moreover, DA D2 receptor sensitivity developed in Pb2+ exposed rats, as evidenced by enhanced quinpirole-induced yawning activity and enhanced quinpirole-induced locomotor activity
(each, P < 0.05). These findings indicate that ontogenetic exposure to lead can have consequences on monoaminergic neuronal function
at an adult stage of life, generally promoting accentuated behavioral effects of direct and indirect monoaminergic agonists,
and related to increased dopamine turnover in basal ganglia.
Special issue dedicated to Dr. Moussa Youdim. 相似文献
102.
Marcin Łoś Piotr Golec Joanna M Łoś Anna Węglewska-Jurkiewicz Agata Czyż Alicja Węgrzyn Grzegorz Węgrzyn Peter Neubauer 《BMC biotechnology》2007,7(1):13
Background
Bacteriophage infections of bacterial cultures cause serious problems in genetic engineering and biotechnology. They are dangerous not only because of direct effects on the currently infected cultures, i.e. their devastation, but also due to a high probability of spreading the phage progeny throughout a whole laboratory or plant, which causes a real danger for further cultivations. Therefore, a simple method for quick inhibition of phage development after detection of bacterial culture infection should be very useful. 相似文献103.
Grochowska Anna Dunaj Justyna Pancewicz Sławomir Czupryna Piotr Majewski Piotr Wondim Mulugeta Tryniszewska Elżbieta Moniuszko-Malinowska Anna 《Experimental & applied acarology》2022,86(4):607-607
Experimental and Applied Acarology - 相似文献
104.
Physiological and antioxidant responses of two accessions of Arabidopsis thaliana in different light and temperature conditions 下载免费PDF全文
Renata Szymańska Beatrycze Nowicka Michał Gabruk Sława Glińska Sylwia Michlewska Jolanta Dłużewska Anna Sawicka Jerzy Kruk Roosa Laitinen 《Physiologia plantarum》2015,154(2):194-209
During their lifetime, plants need to adapt to a changing environment, including light and temperature. To understand how these factors influence plant growth, we investigated the physiological and antioxidant responses of two Arabidopsis accessions, Shahdara (Sha) from the Shahdara valley (Tajikistan, Central Asia) in a mountainous area and Lovvik‐5 (Lov‐5) from northern Sweden to different light and temperature conditions. These accessions originate from different latitudes and have different life strategies, both of which are known to be influenced by light and temperature. We showed that both accessions grew better in high‐light and at a lower temperature (16°C) than in low light and at 23°C. Interestingly, Sha had a lower chlorophyll content but more efficient non‐photochemical quenching than Lov‐5. Sha, also showed a higher expression of vitamin E biosynthetic genes. We did not observe any difference in the antioxidant prenyllipid level under these conditions. Our results suggest that the mechanisms that keep the plastoquinone (PQ)‐pool in more oxidized state could play a role in the adaptation of these accessions to their local climatic conditions. 相似文献
105.
Aleksandra Walczyńska Mateusz Sobczyk Marcin Czarnoleski Jan Kozłowski 《Evolutionary ecology》2015,29(4):525-536
In most ectotherms, compared with development at low temperatures, development at high temperatures results in the acceleration of maturation, which in turn results in a smaller size (temperature–size rule, TSR). It is not known at which developmental stages this thermal response is determined. We exposed different life stages of the rotifer Lecane inermis to 15, 20, or 25 °C to determine whether the TSR in the F1 generation is governed by the thermal conditions experienced by the mothers (F0 generation) during their development, during egg production, or during the development of the eggs or hatchlings. We found that the adult size was affected by the thermal conditions experienced by the mothers and embryos, but not by the conditions during post-hatching growth. We suggest that the thermal plasticity producing the TSR in rotifers may reflect the joint impacts of a maternal effect and a direct effect of the environment during egg development. The two-point control of the TSR resembles the thermal determination of other biological phenomena, similar to the thermally determined sex determination in ectotherms. Our results contribute not only to better understanding the proximate mechanisms of TSR, but also to comprehending the general biological mechanisms of response to temperature, which is one of the most important ecological factors. 相似文献
106.
Effects of litter traits,soil biota,and soil chemistry on soil carbon stocks at a common garden with 14 tree species 总被引:1,自引:0,他引:1
Kevin E. Mueller Sarah E. Hobbie Jon Chorover Peter B. Reich Nico Eisenhauer Michael J. Castellano Oliver A. Chadwick Tomasz Dobies Cynthia M. Hale Andrzej M. Jagodziński Izabela Kałucka Barbara Kieliszewska-Rokicka Jerzy Modrzyński Anna Rożen Maciej Skorupski Łukasz Sobczyk Małgorzata Stasińska Lidia K. Trocha January Weiner Anna Wierzbicka Jacek Oleksyn 《Biogeochemistry》2015,123(3):313-327
107.
108.
109.
Induction of inducible nitric oxide synthase expression in ammonia‐exposed cultured astrocytes is coupled to increased arginine transport by upregulated y+LAT2 transporter 下载免费PDF全文
110.
Paweł Struciński Bożena Morzycka Katarzyna Góralczyk Agnieszka Hernik Katarzyna Czaja Wojciech Korcz 《人类与生态风险评估》2015,21(8):2036-2061
The aim of this study was to characterize short- and long-term risk for consumers associated with dietary intake of pesticide residues in fruits, vegetables, and other foodstuffs available on the Polish market based on 2010–2013 official surveillance results. Among 779 samples collected from 2010 to 2013 no pesticide residue was found in 39.7% samples while 58.5% contained residues at or below the EU Maximum Residue Levels (MRLs). Non-compliances (residues above the respective MRLs) were found in 14 samples (1.8%). Most of the estimated daily intakes were well below 1% of respective acceptable daily intake (ADI) values. The highest intake for children and adults was about 7% and 1.5% of ADI, respectively. For non-compliant results acute risk was characterized. Predicted short-term intakes for children and adults ranged from 0.7% to 425%, and from 0.2% to 100% of respective acute reference dose, respectively. Results of chronic risk characterization show that consumers in Poland are adequately protected; however, incidental cases where residue levels may potentially pose a threat to consumers’ health due to acute exposure cannot be excluded. 相似文献