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161.
Future coral reefs are expected to be subject to higher pCO2 and temperature due to anthropogenic greenhouse gas emissions. Such global stressors are often paired with local stressors thereby potentially modifying the response of organisms. Benthic macroalgae are strong competitors to corals and are assumed to do well under future conditions. The present study aimed to assess the impact of past and future CO2 emission scenarios as well as nutrient enrichment on the growth, productivity, pigment, and tissue nutrient content of the common tropical brown alga Chnoospora implexa. Two experiments were conducted to assess the differential impacts of the manipulated conditions in winter and spring. Chnoospora implexa's growth rate averaged over winter and spring declined with increasing pCO2 and temperature. Furthermore, nutrient enrichment did not affect growth. Highest growth was observed under spring pre‐industrial (PI) conditions, while slightly reduced growth was observed under winter A1FI (“business‐as‐usual”) scenarios. Productivity was not a good proxy for growth, as net O2 flux increased under A1FI conditions. Nutrient enrichment, whilst not affecting growth, led to luxury nutrient uptake that was greater in winter than in spring. The findings suggest that in contrast with previous work, C. implexa is not likely to show enhanced growth under future conditions in isolation or in conjunction with nutrient enrichment. Instead, the results suggest that greatest growth rates for this species appear to be a feature of the PI past, with A1FI winter conditions leading to potential decreases in the abundance of this species from present day levels. 相似文献
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163.
ABA-regulated promoter activity in stomatal guard cells 总被引:4,自引:0,他引:4
Jane E. Taylor Kirstie F. Renwick Alex A.R. Webb Martin R. McAinsh Antonella Furini Dorothea Bartels Ralph S. Quatrano William R. Marcotte Jr. Alistair M. Hetherington 《The Plant journal : for cell and molecular biology》1995,7(1):129-134
CDeT6-19 is an ABA-regulated gene which has been isolated from Craterostigma plantagineum . The CDeT6-19 gene promoter has been fused to the β- glucuronidase reporter gene ( GUS ) and used to stably transform Arabidopsis thaliana and Nicotiana tabacum . This construct has been shown to be expressed in stomatal guard cells and often in the adjacent epidermal cells of both species in response to both exogenous ABA and drought stress. These results indicate that the stomatal guard cell is competent to relay an ABA signal to the nucleus. In contrast GUS expression directed by the promoter from a predominantly seed-specific, ABA-regulated gene, Em , or the promoter from the ABA-regulated CDeT27-45 gene is not detectable in the epidermal or guard cells of tobacco or Arabidopsis in response to ABA. The fact that not all ABA-regulated gene promoters are active in stomatal guard cells suggests that effective transduction of the signal is dependent upon particular regions within the gene promoter or that guard cells lack all or part of the specific transduction apparatus required to couple the ABA signal to these promoters. This suggests that there are multiple ABA stimulus response coupling pathways. The identification of a regulatory sequence from an ABA-induced gene which is expressed in stomatal guard cells creates the possibility of examining the role of Ca2+ and other second messengers in ABA-induced gene expression. 相似文献
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166.
Two pairs of twins were observed in free-ranging Hanuman langurs (Presbytis entellus) at Jodhpur, India. Each twin had a preferred nipple for suckling, the preference of which developed during the first 5 weeks
of life. The behaviour of the twins was mostly synchronized. In more than 60% of all activity bouts both showed the same behaviour,
with “nipple contact” and “playing” prevailing. Differences in physical strength and development were apparent within each
pair. While the total amount of allomothering was almost the same, individual weekly scores differed considerably. 相似文献
167.
Igor Asanović Emilia Strandback Alena Kroupova Djurdja Pasajlic Anton Meinhart Pai Tsung-Pin Nemanja Djokovic Dorothea Anrather Thomas Schuetz Marcin Józef Suskiewicz Sirelin Sillamaa Thomas Köcher Rebecca Beveridge Katarina Nikolic Alexander Schleiffer Martin Jinek Markus Hartl Tim Clausen Javier Martinez 《Molecular cell》2021,81(12):2520-2532.e16
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168.
Antonella Furini Csaba Koncz Francesco Salamini Dorothea Bartels 《Plant cell reports》1994,14(2-3):102-106
Summary An efficient procedure for Agrobacterium tumefaciens- mediated transformation of the desiccation-tolerant plant Craterostigma plantagineum has been developed. Leaf explants were inoculated with A. tumefaciens strain GV3101 carrying the gene for kanamycin- or hygromycin-resistance and the ßglucuronidase reporter gene. Parameters which affected the transformation efficiency were the age of the explant, the degree of wounding and the presence of an antioxidant in the medium. Under optimal conditions, calli originated in more than 80% of leaf explants. Transformed plants were obtained from more than 50% of the cultured calli during regeneration in the presence of a suitable antibiotic. The stable integration of T-DNA was confirmed by Southern blot analysis and its expression by assays for ß-glucuronidase activity.Abbreviations GUS
ß-glucuronidase
- MUG
4-methyl-umbelliferyl ß-D-glucuronide
- ABA
abscisic acid
- NPTII
neomycin phosphotransferase II
- CaMV
cauliflower mosaic virus
- MSAR
modified MS medium
- MS
Murashige and Skoog 相似文献
169.
170.
Hartmut Weiler-Güttler Michaela Sommerfeldt Anastasia Papandrikopoulou Uwe Mischek Dorothea Bonitz reas Frey Matthias Grupe Joachim Scheerer Hans G. Gassen 《Journal of neurochemistry》1990,54(2):444-450
In an approach toward the identification of hitherto unknown proteins involved in the function of the blood-brain barrier, we constructed a pig brain microvessel-derived cDNA library that is enriched in blood-brain barrier specific sequences by means of subtractive cloning. Sequence analysis of selected clones revealed that one of the cDNAs encoded porcine apolipoprotein (apo) A-1. The identity of apo A-1 mRNA was further confirmed by in vitro translation of RNA from brain microvascular endothelial cells and subsequent immunoprecipitation with an antibody against human apo A-1. We further investigated the expression of apo A-1 mRNA in several tissues and in endothelial cells of the pig. It is shown that cultured brain microvascular endothelial cells provide an in vitro model to study the expression and function of apo A-1 in the microvasculature of the brain. 相似文献