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991.
Koeda S Hosokawa M Kang BC Tanaka C Choi D Sano S Shiina T Doi M Yazawa S 《Journal of plant research》2012,125(1):137-145
Temperature is one of the most important environmental factors that influence plant growth and development. Recent studies
imply that plants show various responses to non-extreme ambient temperatures. Previously, we have found that a pepper cultivar
cv. Sy-2 (Capsicum chinense) shows developmental defects at temperatures below 24°C. In this study, to gain new insights into the temperature sensitivity
of cv. Sy-2, temperature-sensitive genes were screened using microarray techniques. At restrictive temperature of 20°C, almost
one-fourth of the 411 up-regulated genes were defense related or predicted to be defense related. Further expression analyses
of several defense-related genes showed that defense-related genes in cv. Sy-2 were constitutively expressed at temperatures
below 24°C. Moreover, accumulation of high level of salicylic acid (SA) in cv. Sy-2 grown at 20°C suggests that the defense
response is activated in the absence of pathogens. To confirm that the defense response is induced in cv. Sy-2 below 24°C,
we evaluated the resistance to biotrophic bacterial pathogen Xanthomonas campestris pv. vesicatoria and necrotrophic fungal pathogen Cercospora capsici. Cv. Sy-2 showed enhanced resistance to X. campestris pv. vesicatoria, but not to C. capsici. 相似文献
992.
Tsuda S Egawa T Ma X Oshima R Kurogi E Hayashi T 《The Journal of nutritional biochemistry》2012,23(11):1403-1409
Chlorogenic acid is an ester of caffeic and quinic acids, and is one of the most widely consumed polyphenols because it is abundant in foods, especially coffee. We explored whether chlorogenic acid and its metabolite, caffeic acid, act directly on skeletal muscle to stimulate 5'-adenosine monophosphate-activated protein kinase (AMPK). Incubation of rat epitrochlearis muscles with Krebs buffer containing caffeic acid (≥0.1 mM, ≥30 min) but not chlorogenic acid increased the phosphorylation of AMPKα Thr(172), an essential step for kinase activation, and acetyl CoA carboxylase Ser(79), a downstream target of AMPK, in a dose- and time-dependent manner. Analysis of isoform-specific AMPK activity revealed that AMPKα2 activity increased significantly, whereas AMPKα1 activity did not change. This enzyme activation was associated with a reduction in phosphocreatine content and an increased rate of 3-O-methyl-d-glucose transport activity in the absence of insulin. These results suggest that caffeic acid but not chlorogenic acid acutely stimulates skeletal muscle AMPK activity and insulin-independent glucose transport with a reduction of the intracellular energy status. 相似文献
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994.
Tanabe K Ishizaki J Ando Y Ito T Nishimoto S 《Bioorganic & medicinal chemistry letters》2012,22(4):1682-1685
We prepared a 5-fluorodeoxyuridine (5-FdUrd) derivative possessing azide methyl group (N(3)-FdUrd) as a novel radiation-activated prodrug. The parent antitumor agent, 5-FdUrd, was released efficiently from N(3)-FdUrd by hypoxic X-irradiation. On the other hand, the activation of N(3)-FdUrd was suppressed upon X-irradiation under aerobic conditions. A biological assay using A549 cells revealed that the cytotoxicity of N(3)-FdUrd was significantly enhanced by hypoxic X-irradiation. 相似文献
995.
Kamata M Yamashita T Kina A Tawada M Endo S Mizukami A Sasaki M Tani A Nakano Y Watanabe Y Furuyama N Funami M Amano N Fukatsu K 《Bioorganic & medicinal chemistry letters》2012,22(14):4769-4772
Spiro-pyrazolidinedione derivatives without quaternary chiral center were discovered by structure-based drug design and characterized as potent acetyl-CoA carboxylase (ACC) inhibitors. The high metabolic stability of the spiro-pyrazolo[1,2-a]pyridazine scaffold and enhancement of the activity by incorporation of a 7-methoxy group on the benzothiophene core successfully led to the identification of compound 4c as an orally bioavailable and highly potent ACC inhibitor. Oral administration of 4c significantly decreased the values of the respiratory quotient in rats, indicating the stimulation of fatty acid oxidation. 相似文献
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999.
Hagura N Hirose S Matsumura M Naito E 《Proceedings. Biological sciences / The Royal Society》2012,279(1742):3476-3481
When confronted with complex visual scenes in daily life, how do we know which visual information represents our own hand? We investigated the cues used to assign visual information to one''s own hand. Wrist tendon vibration elicits an illusory sensation of wrist movement. The intensity of this illusion attenuates when the actual motionless hand is visually presented. Testing what kind of visual stimuli attenuate this illusion will elucidate factors contributing to visual detection of one''s own hand. The illusion was reduced when a stationary object was shown, but only when participants knew it was controllable with their hands. In contrast, the visual image of their own hand attenuated the illusion even when participants knew that it was not controllable. We suggest that long-term knowledge about the appearance of the body and short-term knowledge about controllability of a visual object are combined to robustly extract our own body from a visual scene. 相似文献
1000.
It is well known that subjects tend to misattribute task-irrelevant signals, incorporating them into the information on which a decision is made. Such misattribution has been reported to originate only from a social or a cognitive stage of information processing. However, we provide the initial evidence that misattribution also originates at a lower, visuomotor stage. This type of misattribution occurs only when subjects do not notice a visuomotor conflict. Misattribution at a social or a cognitive stage facilitates decision-making if the misattributed information is consistent with the decision and impedes decision-making if the information is in conflict with the decision. However, misattribution originating at a visuomotor stage only impedes decision-making, suggesting a fundamental difference between the mechanisms for the two types of misattribution. Furthermore, misattribution effects that originate in a visuomotor interaction stage also affect subjective preference ratings, suggesting that the misattribution exerts an influence on global brain processing. 相似文献