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171.
Woodland biodiversity, palaeo-human ecology and some implications for conservation management 总被引:2,自引:0,他引:2
Richard Tipping James Buchanan Althea Davies Eileen Tisdall 《Journal of Biogeography》1999,26(1):33-43
This paper appraises the role of prehistoric human societies in modifying the natural woodland biodiversity of several regions throughout Scotland. It draws attention to the likelihood that, contrary to popular belief, biodiversity was enhanced by interactions between agricultural communities and woodlands. The possible purposefulness of such interactions is discussed. Mindful of the present concern to re-establish ‘native’ woodlands in many parts of northern Britain, we then review three approaches to the identification of native tree types in Scotland, and conclude that insufficient attention in reafforestation schemes is being paid to (a) the palaeoecological record as a record of native woodland or (b) the likely former high taxonomic diversity of woodlands. Both these failings will lead to the creation of new woodlands lacking in species diversity. 相似文献
172.
S.J. Hersey Melissa Miller Althea Owirodu 《Biochimica et Biophysica Acta (BBA)/General Subjects》1982,714(1):143-151
The role played by glucose in providing energy for acid formation was studied in isolated gastric glands from rabbit. The widely-used inhibitors of glycolysis, iodoacetic acid and iodoacetamide were found to inhibit glucose oxidation as well as the indicators of acid formation, respiration and accumulation of aminopyrine. However, the potent inhibition of acid formation was found to involve a nonspecific mechanism other than the simple inhibition of glycolysis. An alternative approach involved use of the glucose transport inhibitor, phloretin. Phloretin blocked glucose oxidation and also inhibited functional responses. Acid formation was restored easily by the addition of pyruvate or various other oxidizable substrates. Measurement of lactate formation in the absence of exogenous glucose showed that the gastric glands contain very little glycogen. Addition of external glucose resulted in a 10-fold increase in lactate formation and this rate was stimulated further by histamine and rotenone. Rotenone also inhibited both respiration and aminopyrine accumulation; however, the inhibition was not complete. Phloretin treatment resulted in total inhibition of the residual aminopyrine accumulation after rotenone treatment. The results are interpreted to indicate that gastric glands are dependent almost totally on external substrate supply to support acid formation; and, that while anaerobic glucose metabolism can sustain a very low level of acid formation, the major role of glucose is to yield pyruvate equivalents for subsequent oxidation. 相似文献
173.
D. Poncelet R. Neufeld B. Bugarski B. G. Amsden J. Zhu M. F. A. Goosen 《Applied microbiology and biotechnology》1994,42(2-3):251-255
Polymer microbead production by parallel plate electrostatic extrusion is presented. Factors affecting microbead size such as needle gauge, electrostatic potential, distance between needle and collecting solution, and polymer solution concentration and flow rate were evaluated. Smaller microbeads resulted from reduced needle diameter, reduced needle to collecting solution distance, increased electrostatic potential, and reduced polymer solution concentration and flow rate. In terms of process scale-up, it was shown that a multi-needle (20) device could continuously produce relatively uniform beads via electrostatics. The technology was demonstrated to be feasible for cell encapsulation or immobilization as there was no detectable effect of applied potential onSpodoptera frugiperda viability. 相似文献
174.
Lot Snijders Blok Y. Max Goosen Leenke van Haaften Karen van Hulst Simon E. Fisher Han G. Brunner Jos I. M. Egger Tjitske Kleefstra 《Genes, Brain & Behavior》2021,20(7):e12761
SATB2-associated syndrome (SAS) is a neurodevelopmental disorder caused by heterozygous pathogenic variants in the SATB2 gene, and is typically characterized by intellectual disability and severely impaired communication skills. The goal of this study was to contribute to the understanding of speech and language impairments in SAS, in the context of general developmental skills and cognitive and adaptive functioning. We performed detailed oral motor, speech and language profiling in combination with neuropsychological assessments in 23 individuals with a molecularly confirmed SAS diagnosis: 11 primarily verbal individuals and 12 primarily nonverbal individuals, independent of their ages. All individuals had severe receptive language delays. For all verbal individuals, we were able to define underlying speech conditions. While childhood apraxia of speech was most prevalent, oral motor problems appeared frequent as well and were more present in the nonverbal group than in the verbal group. For seven individuals, age-appropriate Wechsler indices could be derived, showing that the level of intellectual functioning of these individuals varied from moderate–mild ID to mild ID-borderline intellectual functioning. Assessments of adaptive functioning with the Vineland Screener showed relatively high scores on the domain “daily functioning” and relatively low scores on the domain “communication” in most individuals. Altogether, this study provides a detailed delineation of oral motor, speech and language skills and neuropsychological functioning in individuals with SAS, and can provide families and caregivers with information to guide diagnosis, management and treatment approaches. 相似文献
175.
Red list species densities of birds (maximally 22 km−2), and angiosperms (maximally 39 km−2) were used as biodiversity indicators in 21 larger complexes of wetlands across the Netherlands. Their covariability with
a range of indicators of human land use was assessed, including population, road and visitor density, area covered by agriculture,
open water, forest and residential housing. Data were collected on the wetland complexes as well as for a perimeter with 10 km
radius. In a principal components analysis (PCA) with all land use variables, it was found that the population-density-related
complex of urbanisation, fragmentation (by roads), and intensity of fertilizer use together explained most of the variability
present (i.e. the first PCA axis explained 50%), whilst land use within these complexes was second with an additional 19%
and waterside recreation third with 12%. Red list bird species density did not correlate with that of angiosperms, nor with
any of the indicators used. For the 13 complexes on organic peatland, we observed an increase in maximum red list angiosperm
species density with the proportion of open marshland (P < 0.01, r
2 > 0.55), which, in turn, was negatively and closely correlated with the first PCA axis reflecting an urbanisation gradient across
the Netherlands. 相似文献