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971.
Ekmekçigil Münire Bayraktar Meltem Akkuş Özge Gürel Aynur 《Plant Cell, Tissue and Organ Culture》2019,136(3):451-464
Plant Cell, Tissue and Organ Culture (PCTOC) - An efficient in vitro mass propagation through protocorm-like bodies (PLBs) was established in Cattleya forbesii Lindl., a commercially important... 相似文献
972.
Shwetha Ravichandran Brian S. Finlin Philip A. Kern Sabire Özcan 《生物化学与生物物理学报:疾病的分子基础》2019,1865(3):570-576
Sphingosine kinases phosphorylate sphingosine to sphingosine 1?phosphate (S1P), which functions as a signaling molecule. We have previously shown that sphingosine kinase 2 (Sphk2) is important for insulin secretion. To obtain a better understanding of the role of Sphk2 in glucose and lipid metabolism, we have characterized 20- and 52-week old Sphk2?/? mice using glucose and insulin tolerance tests and by analyzing metabolic gene expression in adipose tissue. A detailed metabolic characterization of these mice revealed that aging Sphk2?/? mice are protected from metabolic decline and obesity compared to WT mice. Specifically, we found that 52-week old male Sphk2?/? mice had decreased weight and fat mass, and increased glucose tolerance and insulin sensitivity compared to control mice. Indirect calorimetry studies demonstrated an increased energy expenditure and food intake in 52-week old male Sphk2?/? versus control mice. Furthermore, expression of adiponectin gene in adipose tissue was increased and the plasma levels of adiponectin elevated in aged Sphk2?/? mice compared to WT. Analysis of lipid metabolic gene expression in adipose tissue showed increased expression of the Atgl gene, which was associated with increased Atgl protein levels. Atgl encodes for the adipocyte triglyceride lipase, which catalyzes the rate-limiting step of lipolysis. In summary, these data suggest that mice lacking the Sphk2 gene are protected from obesity and insulin resistance during aging. The beneficial metabolic effects observed in aged Sphk2?/? mice may be in part due to enhanced lipolysis by Atgl and increased levels of adiponectin, which has lipid- and glucose-lowering effects. 相似文献
973.
974.
Effects of repeated desflurane and sevoflurane anesthesia on enzymatic free radical scavanger system
Dikmen B Unal Y Pampal HK Nurlu N Kurtipek O Canbolat O Ozoğul C Kavutcu M 《Molecular and cellular biochemistry》2007,294(1-2):31-36
Background: To investigate the possible effects of repeated sevoflurane and desflurane anesthesia on hepatocellular system by evaluating
the free radical metabolism, hepatocellular enzymes and histopatholgical changes in rats. Methods: Four groups of animals were studied. Sevoflurane 2% (v/v) and desflurane 6% (v/v) in air/O2 were administered to animals in group II (n = 9) and III (n = 9) respectively. 100% (v/v) O2 was administered in group IV (n = 9). Administration was done for 60 minutes over 3 days. Nine animals were allocated to control group (group I), superoxide
dismutase (SOD), catalase (CAT), glutathion peroxidase (GSH-Px), glutathione-s-transferase (GST) and thiobarbituric acid reactive
substances (TBARS) were studied. Also electron microscopy was performed. Results: Catalase, SOD, GSH-Px, GST activities and TBARS levels were significantly higher in groups II and III than in group I (p < 0.05). All parameters were significantly higher in groups II versus group IV (p < 0.05). On the other hand, SOD, GSH-Px and GST activities were significantly elevated in group III than IV, but CAT activity
and TBARS levels were not significantly. Catalase, SOD, GSH-Px, GST but not TBARS levels were significantly higher in groups
II and III than in group IV (p < 0.05). TBARS levels were higher in group III than in group IV, but this elevation was not statistically significant. CAT,
SOD and GSH-Px activities were significantly higher in groups II than in group III (p < 0.05). Conclusion: Although electron microscopy findings were similar for group II and III, we can conclude that sevoflurane might cause more
cellular damage than desflurane by causing higher activation of free radical metabolising enzymes. 相似文献
975.
Meryem Yeşim Çelik Mehmet Bedrettin Duman Merve Sariipek Gülşen Uzun Gören Dilara Kaya Öztürk 《Molluscan research.》2019,39(3):234-240
ABSTRACTThe fatty acid and mineral matter compositions of the visceral mass and pedal mass of wild and farmed Cornu aspersum were compared. The relative fatty acid amounts of the visceral and pedal masses of wild and farmed snails are: polyunsaturated fatty acid (PUFA) > saturated fatty acid (SFA) > monounsaturated fatty acid (MUFA), PUFA?>?SFA?>?MUFA, MUFA?>?PUFA?>?SFA and PUFA?>?MUFA?>?SFA, respectively. Wild snails had a higher concentration of iron and zinc than farmed snails. Selenium was 2.82 times higher in the pedal mass of farmed snails than the pedal mass of wild snails. Ca:P ratios in the visceral mass of wild snails, visceral mass and pedal mass of farmed snails were 1.76:1, 1.12:1 and 3.87:1 respectively. Both wild and farmed snails have high contents of oleic, linoleic, eicosapentaenoic and docosahexaenoic fatty acids and are a good source of minerals. Careful attention should be paid, however, as to which diet will be used during farming because the composition of fatty acid in the snail is affected by diet. 相似文献
976.
Russian Journal of Genetics - The aim of this study is an evaluation of the genetic diversity among nine emmer wheat [Triticum turgidum L. ssp. dicoccon (Schrank) Thell.] landrace populations,... 相似文献
977.
Genetic and morphological divergence along the littoral–pelagic axis in two common and sympatric fishes: perch,Perca fluviatilis (Percidae) and roach,Rutilus rutilus (Cyprinidae)
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Leanne Faulks Richard Svanbäck Peter Eklöv Örjan Östman 《Biological journal of the Linnean Society. Linnean Society of London》2015,114(4):929-940
Individuals are constantly in competition with one another and, on both ecological and evolutionary timescales, processes act to reduce this competition and promote the gain of fitness advantages via diversification. Here we have investigated the genetic (AFLP) and morphological (geometric morphometrics) aspects of the littoral–pelagic axis, a commonly observed resource polymorphism in freshwater fishes of postglacial lakes. We found a large degree of variation in the genetic and morphological divergence between littoral and pelagic perch and roach across Swedish lakes. Although there was evidence of assortative mating (elevated kinship values) in both species, we could not find any significant coupling of morphology and genetic divergence. Instead, there was evidence that the extent of resource polymorphism may be largely caused by phenotypic plasticity. These results suggest that assortative mating, which can lead to genetically determined adaptive divergence, does occur in these species, particularly perch, but not according to genetically fixed morphological traits. The behavioural mechanisms facilitating associative mating need to be investigated to explore the interaction between phenotypic plasticity and adaptive genetic divergence and their roles in diversification. © 2015 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114 , 929–940. 相似文献
978.
Relationship between starch degradation and carbon demand for maintenance and growth in Arabidopsis thaliana in different irradiance and temperature regimes 总被引:1,自引:0,他引:1
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SARAH M. PILKINGTON BEATRICE ENCKE NICOLE KROHN MELANIE HÖHNE MARK STITT EVA‐THERESA PYL 《Plant, cell & environment》2015,38(1):157-171
Experiments were designed to compare the relationship between starch degradation and the use of carbon for maintenance and growth in Arabidopsis in source‐limited and sink‐limited conditions. It is known that starch degradation is regulated by the clock in source‐limited plants, which degrade their starch in a linear manner such that it is almost but not completely exhausted at dawn. We asked whether this response is maintained under an extreme carbon deficit. Arabidopsis was subjected to a sudden combination of a day of low irradiance, to decrease starch at dusk, and a warm night. Starch was degraded in a linear manner through the night, even though the plants became acutely carbon starved. We conclude that starch degradation is not increased to meet demand in carbon‐limited plants. This network property will allow stringent control of starch turnover in a fluctuating environment. In contrast, in sink‐limited plants, which do not completely mobilize their starch during the night, starch degradation was accelerated in warm nights to meet the increased demand for maintenance and growth. Across all conditions, the rate of growth at night depends on the rate of starch degradation, whereas the rate of maintenance respiration decreases only when starch degradation is very slow. 相似文献
979.
Implications for catch composition and revenue in changing from diamond to square mesh codends in the northeastern Mediterranean
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The objective of this study was to estimate the potential short‐term economic loss as a result of replacing the commercial diamond codend with a square mesh codend, and to compare fish lengths captured in 40 mm square (S40) vs 44 mm commercial hand‐woven diamond (CD44) mesh codends for red mullet (Mullus barbatus), common pandora (Pagellus erythrinus), bogue (Boops boops), European hake (Merluccius merluccius), axillary seabream (Pagellus acarne), and brushtooth lizardfish (Saurida undosquamis). A total of 20 hauls (10 hauls for S40 and 10 hauls for CD44) were conducted onboard a commercial trawler between 27 February and 11 April 2012 in Mersin Bay in the northeastern Mediterranean. Results showed that the 40 mm square mesh codend caught significantly fewer juveniles of all aforementioned species. However, when changing from the commercial diamond codend to the 40 mm square mesh codend the potential economic loss of revenue was found to be 40% in the study period, which covered the final 6 weeks of the fishing season. 相似文献
980.
Quantitative comparison of a human cancer cell surface proteome between interphase and mitosis
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Mohammad H Qureshi Yusuke Toyoda Bernhard Y Renard Gürkan Mollaoglu Nazlı E Özkan Selda Bulbul Ina Poser Wiebke Timm Anthony A Hyman Timothy J Mitchison Judith A Steen 《The EMBO journal》2015,34(2):251-265
The cell surface is the cellular compartment responsible for communication with the environment. The interior of mammalian cells undergoes dramatic reorganization when cells enter mitosis. These changes are triggered by activation of the CDK1 kinase and have been studied extensively. In contrast, very little is known of the cell surface changes during cell division. We undertook a quantitative proteomic comparison of cell surface‐exposed proteins in human cancer cells that were tightly synchronized in mitosis or interphase. Six hundred and twenty‐eight surface and surface‐associated proteins in HeLa cells were identified; of these, 27 were significantly enriched at the cell surface in mitosis and 37 in interphase. Using imaging techniques, we confirmed the mitosis‐selective cell surface localization of protocadherin PCDH7, a member of a family with anti‐adhesive roles in embryos. We show that PCDH7 is required for development of full mitotic rounding pressure at the onset of mitosis. Our analysis provided basic information on how cell cycle progression affects the cell surface. It also provides potential pharmacodynamic biomarkers for anti‐mitotic cancer chemotherapy. 相似文献