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371.
Almost equivalence of combinatorial and distance processes for discrimination in multielement images
Under certain experimental conditions, visual discrimination performance in multielement images is closely related to visual identification performance: elements of the image are distinguished only insofar as they appear to have distinct, discrete, internal characterizations. This report is concerned with the detailed relationship between such internal characterizations and observable discrimination performance. Two types of general processes that might underline discrimination are considered. The first is based on computing all possible internal image characterizations that could allow a correct decision, each characterization weighted by the probability of its occurrence and of a correct decision being made. The second process is based on computing the difference between the probabilities associated with the internal characterizations of the individual image elements, the difference quantified naturally with an l
(p) norm. The relationship between the two processes was investigated analytically and by Monte Carlo simulations over a plausible range of numbers n of the internal characterizations of each of the m elements in the image. The predictions of the two processes were found to be closely similar. The relationship was precisely one-to-one, however, only for n = 2, m = 3, 4, 6, and for n > 2, m = 3, 4, p = 2. For all other cases tested, a one-to-one relationship was shown to be impossible. 相似文献
372.
373.
Triiodothyronine-Induced Shortening of Chromatin Repeat Length in Neurons Cultured in a Chemically Denned Medium 总被引:1,自引:0,他引:1
Alessandro Cestelli Italia Di Liegro Daniele Castiglia Roberto Gristina Donatella Ferraro Giuseppe Salemi Giovanni Savettieri 《Journal of neurochemistry》1987,48(4):1053-1059
At the time of terminal differentiation, mammalian cortical neurons undergo a dramatic change in the structural organization of their chromatin: the nucleosomal repeat length shortens from approximately 200 base pairs in fetuses to a value of 165 base pairs after birth. These events occur several days after the end of neuronal proliferation. Previously, we reported that rat cortical neurons cultured in a very selective synthetic medium were not yet programmed to these events at the end of mitotic cycles. Herein, we report that addition of triiodothyronine to neuronal cultures induces a shortening of the chromatin repeat length comparable to the natural one. 相似文献
374.
Paul J. Ferraro Merlin M. Hanauer 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2015,370(1681)
To develop effective protected area policies, scholars and practitioners must better understand the mechanisms through which protected areas affect social and environmental outcomes. With strong evidence about mechanisms, the key elements of success can be strengthened, and the key elements of failure can be eliminated or repaired. Unfortunately, empirical evidence about these mechanisms is limited, and little guidance for quantifying them exists. This essay assesses what mechanisms have been hypothesized, what empirical evidence exists for their relative contributions and what advances have been made in the past decade for estimating mechanism causal effects from non-experimental data. The essay concludes with a proposed agenda for building an evidence base about protected area mechanisms. 相似文献
375.
Arno G. Steinig An-Hu Li Jing Wang Xin Chen Hanqing Dong Caterina Ferraro Meizhong Jin Mridula Kadalbajoo Andrew Kleinberg Kathryn M. Stolz Paula A. Tavares-Greco Ti Wang Mark R. Albertella Yue Peng Linda Crew Jennifer Kahler Julie Kan Ryan Schulz Mark J. Mulvihill 《Bioorganic & medicinal chemistry letters》2013,23(15):4381-4387
A series of novel 6-aminofuro[3,2-c]pyridines as kinase inhibitors is described, most notably, OSI-296 (6). We discuss our exploration of structure–activity relationships and optimization leading to OSI-296 and disclose its pharmacological activity against cMET and RON in cellular assays. OSI-296 is a potent and selective inhibitor of cMET and RON kinases that shows in vivo efficacy in tumor xenografts models upon oral dosing and is well tolerated. 相似文献
376.
C Mostacci M Ferraro F Pelliccia N Archidiacono M Rocchi A de Capoa 《Cytogenetics and cell genetics》1980,28(1-2):3-9
Simultaneous Q- and R-type banding patterns in human chromosomes have been achieved by staining with chromomycin A3. Some peculiarities of these patterns as compared to the patterns induced by other fluorochromes are described. The resolution power of this technique in analyzing structural rearrangements of human chromosomes is discussed. 相似文献
377.
D L Crandall B M Goldstein G D Ferraro P Cervoni 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1991,198(2):747-753
To determine the biochemical and hemodynamic responses to aortic ligation, and to assess the survival rate after the induction of hypertension, 90 normotensive rats were subjected to surgical constriction of the abdominal aorta. Mortality, left ventricular hemodynamics, myocardial biochemical assays, and plasma renin assays were determined 1 week, 1 month, 3 months, or 1 year later. Mortality was greatest between 1 week and 3 months after aortic ligation, during which plasma renin activity was significantly elevated. The rate of left ventricular pressure rise, contractile index, and myocardial alpha-adrenoceptor number were increased at 1 month, but were comparatively depressed at 3 months after the operation, suggesting that the heart was in failure at this time. At 1 year after ligation, hemodynamic and biochemical parameters continued toward normalization. Our data suggest that, in this rodent model, cardiac pump failure occurs through a combination of time-dependent, pressure-induced mechanical adaptations and myocardial biochemical changes that involve both the renin-angiotensin and sympathetic nervous systems. The observed relationship between mortality, myocardial hemodynamics, and biochemical parameters may be used for additional basic research investigations concerning the early periods of cardiac failure. 相似文献
378.
Steven P. Ferraro 《Oikos》2013,122(11):1541-1553
“Science is organized knowledge.” Immanuel Kant (1724–1804) Ecological periodic tables are an information organizing system with categorical habitat types as elements and predictably recurring (periodic) properties of a target biotic community, such as its relative species richness, abundance and biomass, as attributes. Ecological periodic tables are founded on the ecological tenet that habitats structure biotic communities and its corollary that habitats are templets for ecological strategies. They are a durable, open and flexible system that accommodates all operationally defined habitat types and biotic communities for which the periodicity of habitat usage patterns by a biotic community have been empirically substantiated. Discovering quantitative, periodic habitat usage patterns requires quantitative, representative, unbiased sampling of a biotic community across habitat types at ecologically relevant temporal and spatial scales. Like chemical periodic tables, the Linnaean system of classification and the Hertzsprung–Russell diagram in chemistry, biology and astronomy, respectively, ecological periodic tables are simple, easy to understand, exceptionally useful and they foster the expansion of scientific understanding, inquiry and theory. 相似文献
379.
380.