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891.
In capture–recapture models, survival and capture probabilities can be modelled as functions of time‐varying covariates, such as temperature or rainfall. The Cormack–Jolly–Seber (CJS) model allows for flexible modelling of these covariates; however, the functional relationship may not be linear. We extend the CJS model by semi‐parametrically modelling capture and survival probabilities using a frequentist approach via P‐splines techniques. We investigate the performance of the estimators by conducting simulation studies. We also apply and compare these models with known semi‐parametric Bayesian approaches on simulated and real data sets. 相似文献
892.
893.
J Gromadzka-Ostrowska M Lehman-Kryszak B Zalewska K Jakubóv H Go?liński 《Chronobiologia》1986,13(3):215-226
Changes in blood plasma calcium, inorganic phosphorus, magnesium, zinc, iron, copper, sodium and potassium concentrations over a 3-year period were investigated in primitive goats. Blood plasma mineral concentrations were determined by atomic absorption and a colorimetric method. Changes in Zn and Ca concentrations are season dependent, potassium levels show only a long-term change tendency, and magnesium and inorganic phosphorus had constant levels throughout the investigation period. Iron, copper and sodium showed both long-term change tendencies and more or less marked season related changes. 相似文献
894.
Aurlien Bruel Jakub Kronenberg Nadge Troussier Bertrand Guillaume 《Journal of Industrial Ecology》2019,23(1):12-21
The circular economy (CE) is a new model for the production and consumption of goods, which has attracted wide political attention as a strategy toward sustainability. However, the theoretical foundation of CE remains poorly structured and insufficiently explored. Recent studies have shown that the CE model draws on different schools of thought and that its origins are mainly rooted in fields such as industrial ecology (IE) and ecological economics (EE). In this article, we investigate the links between CE, IE, and EE and provide an overview of the similarities and differences between these fields. At the same time, we analyze to what extent the linkages between IE and EE can create a coherent body of knowledge for CE, and be used to identify further research opportunities. This paper shows that, until now, research on CE seems to be mainly rooted in the field of IE and based on concepts and tools that already exist in other fields, rather than inventing new ones. The reconciliation of IE and EE could provide a mechanism to extend beyond such a narrow focus, and increase knowledge of the theoretical and practical framework of CE to benefit sustainability. 相似文献
895.
Rensch’s rule describes the pattern of sexual size dimorphism (SSD) claiming that in taxa where males are the larger sex,
larger species generally exhibit higher male to female body size ratios. Agreement with Rensch’s rule is manifested by the
slope of the allometric relationship between male and female body size exceeding one. In this paper we have tested the hypothesis
that recent rapid evolutionary changes of body size accompanying domestication process and morphological radiation of domestic
breeds follow Rensch’s rule. We have analyzed literature data on adult body size of males and females in domestic cows, yaks,
buffaloes and other bovines (315, 12, 24 and 2 breeds, respectively) and compared it with SSD in 18 wild species/subspecies
of the subfamily Bovinae. Male to female body mass ratio in domestic cows (1.48) was fairly comparable to that found in other species of domestic and
wild bovines except domestic buffaloes (1.19). In cows we have demonstrated clear positive allometry of male to female body
mass ratio (slope 1.21) predicted by Rensch’s rule, however, no such clear relationship was found when body mass was replaced
by shoulder height. These findings are in agreement with those we have previously reported in other livestock species, goats
and sheep. 相似文献
896.
J Gill K Jakubów E Kompanowska-Jezierska A Kott D Szumska 《Comparative biochemistry and physiology. A, Comparative physiology》1985,82(1):167-178
In 34 pure breed Arabian horses divided into four groups (Gr. I--10 pregnant mares, Gr. II--7 barren mares, Gr. III--10 foals born in 1981, Gr. IV--7 foals born in 1982) seasonal changes in total blood serum protein, its electrophoretic fractions and the activity of AspAT and AlAT were studied. Seasonal cyclicity was found in all groups in the amount of total serum proteins, and alpha 2- and beta 1-globulin fractions. Cyclicity was found in the level of albumin and activity of AspAT in three groups, not Gr. II, and in gamma-globulin, not Gr. IV. beta 2-globulin and AlAT cyclicity was found in two groups and alpha 1-globulin cyclicity was found only in Gr. II. Out of nine indices studied, cyclicity was found in eight of them in pregnant mares, Gr. I; in seven in older foals, Gr. III; in six in the young foals, Gr. IV; and in five in barren mares, Gr. II. 相似文献