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81.
Multivariate binary discrimination by the kernel method 总被引:10,自引:0,他引:10
82.
83.
The NADP+ specific glutamate dehydrogenase from wild-type forms a stable binary complex with NADPH. This can combine with L-glutamate, α-ketoglutarate or the substrate analogue D-glutamate to form ternary complexes which can be distinguished by their different fluorescence properties. The affinity of the enzyme for NADPH diminishes with increases in pH or ionic strength of the solution. Experimental data obtained using modified glutamate dehydrogenases from mutant strains of suggest that the reduced-coenzyme binding sites observed fluorimetrically are the same as those observed by enzyme kinetics. 相似文献
84.
Fifteen amines having a profound effect on carotenogenesis in Marsh seedless grapefruit are reported. The compounds fall into three series: Et2N(CH2)nMe (n = 4–8), Et2N(CH2)nPh (n = 1–5), and Et2NCH2CH2OC6H4R (R=H, p-Me, p-Et, p-iso-Pr, p-tert-Bu), There was up to an 11-fold increase in the total carotene content. Lycopene, not normally accumulated, became a major pigment. The inducing ability of the amines on carotenoid biosynthesis is correlated with the octanol-water partition coefficient. The mode of action appears to be similar to that of 2-(4-chlorophenylthio)triethylamine hydrochloride. 相似文献
85.
86.
Developing desorption isotherms for inorganic phosphorus (P) is a time-consuming and non-standardized procedure. Anion exchange
membranes (AEMs) have been successfully used in studies of P desorption kinetics and total membrane-desorbable P, but rarely
have they been used for developing P desorption isotherms. Our study had two objectives: (1) to evaluate the suitability of
using multiple strips of AEMs (termed the Multiple AEM Method) to develop P desorption isotherms; and (2) to compare the Multiple
AEM Method with a sequential-extraction approach using AEMs (termed the Sequential AEM Method) to determine if the manner
in which AEMs were used would influence the slope of the desorption isotherm, i.e. the partition coefficient. Both methods
yielded well-defined, but numerically different desorption isotherms for all levels of sorbed P. However, estimated K
d
values among methods were equivalent in the low and medium levels of P sorbed. The Multiple AEM method was quicker than the
Sequential AEM method, but both gave similar K
d
values in an agriculturally significant range of soil solution concentrations. These methods should be tested on a range
of soil type to determine their suitability in developing P desorption isotherms and to move toward method standardization
for desorption isotherms. 相似文献
87.
Growing evidence demonstrates that fluctuating metal stressors can have profound impact on the ecophysiological responses in aquatic species. However, how environmental stochasticity affects the complex damage-recovery dynamics in organisms remains difficult to predict. The objective of this paper was to investigate the stochastic behavior in the damage-recovery dynamics in tilapia in response to pulse waterborne copper (Cu). We developed a mathematical framework that allows discrimination between damage and recovery processes in tilapia exposed to designed pulse Cu scenarios. We built deterministic nonlinear models for the damage-recovery dynamics that produce response surfaces describing killing/recovery rate–Cu-pulse interval interactions. Here we showed that the stochastic switching behavior arose from competition among killing, recovery rates, and Cu pulse frequency. This competition resulted in an ultrasensitivity appeared in whole body, gills, muscle, liver, and kidney with Hill coefficients of ≥7, 4, 7, 5, and 5, respectively, at Cu 3 mg L−1, dilution rate 0.05 h−1, and pulse interval 72 h, indicating that a stochastic switch-like response was generated. We argue that the role of gill-associated Hill coefficient as a direct signal of the stochastic switch-like response in the damage-recovery dynamics in response to pulse metal stressor can serve as a sensitive indicator for risk detection in fluctuating environments. Our approach constitutes a general method to identify the stochastic switch-like response for aquatic species exposed to fluctuating metal stressors, which may help to predict and, eventually, expand our understanding of the damage-recovery dynamics. Finally, we implicate that Hill coefficient-based switch-like signal and its damage with hazard response can be linked in an information theoretic framework to handle environmental stochasticity. 相似文献
88.
Correlated binary regression using a quadratic exponential model 总被引:5,自引:0,他引:5
89.
Functional redundancy of multiple forest taxa along an elevational gradient: predicting the consequences of non‐random species loss
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Akira S. Mori Takayuki Shiono Takashi F. Haraguchi Aino T. Ota Dai Koide Takayuki Ohgue Ryo Kitagawa Ryo Maeshiro Toe Toe Aung Taizo Nakamori Yusuke Hagiwara Shunsuke Matsuoka Anzu Ikeda Takuo Hishi Satoru Hobara Eri Mizumachi Andreas Frisch Göran Thor Saori Fujii Takashi Osono Lena Gustafsson 《Journal of Biogeography》2015,42(8):1383-1396
90.
Makoto Tomimoto 《仿生工程学报(英文版)》2014,11(1):98-108
To achieve favorable Frictional Tactile Sensation (FTS) for robot and humanoid fingers, this report investigated the effects of human finger sweat on Friction Coefficient (FC) and verified the effectiveness of artificial sweat on FTS tbr a humanoid finger. The results show that the model sweat (salt and urea water faked real sweat) increases the FC of the real finger sliding on the high hygroscopic and rough surface (paper), whereas on the low hygroscopic and smooth surface (PMMA), the sweat forms a fluid film and decreases FC, restricting severe finger adhesion. Further, the film formation and capillary adhesion force of sweat were discussed. The experimental results with the artificial sweats (ethanol and water) and humanoid finger (silicone rubber skin with tactile sensors) verifies the effectiveness. The artificial sweat restricts severe adhesion (stick-slip vibration), and enhances cognitive capability of FTS. 相似文献