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91.
92.
In urbanized contexts, a progressive disconnection from nature, mainly experienced by the youngest generation, is evident. In this sense, detection of species more suitable for a nature-related experience becomes of primary importance to increase pro-environmental behaviors in children. Here, we propose a simple, quick, and explorative procedure for selecting a set of Experiential Key Species (EKS). Two practical examples are provided for two contexts (a urban park and a suburban wetland) where a large amount of data on vertebrate animal species are available. Depending on their density and eco-behavioral features, each species stimulates different experiences, here considered as a product of intensity and frequency of occurrence. Therefore, for each species we calculated an Experiential Magnitude score on a three-level scale with an expert-based method. We obtained 14 EKS in the urban park site (18% of total) and 18 EKS in the suburban wetland site (9.4%). We observed that in both sites EKS mainly include: (i) heterotherm species (mainly, fishes, amphibians, and water-related reptiles) and (ii) non-native species (about 36% in the urban park and about 17% in the suburban wetland). This information suggests that (i) following a conservation zoning approach, lakes, streams, and their shores may be considered the best experiential sites for children, and (ii) in conservation measures aimed to improve experience and pro-environmental behaviors in younger generations, the role of non-native species (that are of low or null conservation interest) might be relevant. In-deed, individuals of these species (i) are easily detectable, and (ii) may be collected, handled, and farmed with a limited (or absent) impact on biodiversity. In many anthropized contexts, these are the only species that can provide nature experience for younger generations. Based on our observations, we recommend practitioners (i) to adopt the procedure of EKS selection in critical contexts, also adding further regime attributes (area utilized, seasonal duration) to calculate the experiential magnitude score, and (ii) to test the effectiveness of this selection in conservation education projects. 相似文献
93.
94.
Corrado Marcenò Riccardo Guarino Javier Loidi Mercedes Herrera Maike Isermann Ilona Knollová Lubomír Tichý Rossen T. Tzonev Alicia Teresa Rosario Acosta Úna FitzPatrick Dmytro Iakushenko John A. M. Janssen Borja Jiménez‐Alfaro Zygmunt Kącki Iva Keizer‐Sedláková Vitaliy Kolomiychuk John S. Rodwell Joop H. J. Schaminée Urban Šilc Milan Chytrý 《应用植被学》2018,21(3):533-559
95.
The base composition of the poly(A) segment of duck 10S RNA was determined to be 92% AMP and 8% GMP. The GMP was probably the result of contamination of poly(A) with other segments of the RNA. A comparison of the theoretical and determined base compositions of the whole 10S RNA molecule suggested that it contains, besides a coding sequence, two noncoding sequences only one of which is poly(A).Abbreviations AMP
adenylic acid
- GMP
guanylic acid
- CMP
cytidylic acid
- UMP
uridylic acid
- SDS
sodium dodecyl sulfate
- EDTA
ethylene diamine tetraacetic acid
- TCA
trichloroacetic acid 相似文献
96.
Primary familial brain calcification with a novel SLC20A2 mutation: Analysis of PiT‐2 expression and localization 下载免费PDF全文
97.
Fausto Tinti Andrea Colombari Maria Vallisneri Corrado Piccinetti Anna Maria Stagni 《Marine biotechnology (New York, N.Y.)》1999,1(1):20-24
The 5′-end of the mitochondrial control region of three Pleuronectiformes from the Adriatic Sea, Platichthys flesus italicus (Adriatic flounder), Solea vulgaris (common sole), and Solea kleini (Klein's sole), was sequenced and compared with that of six other flatfish species from the families Pleuronectidae and Bothidae.
The sequence structures of all flatfishes appear very similar and consist of alternate short segments with low, medium, and
high rates of nucleotide substitution. Four conserved 19-bp repeats occur at the beginning of the European and Adriatic flounder
sequences. The common occurrence of tandem arrays in fish control regions could be related to a stable secondary structure.
Molecular phylogenetic relationships among Pleuronectiformes agree well with previous morphologic data at all taxonomic levels.
Molecular analyses could therefore contribute to resolving phylogenetic and taxonomic debates within the Pleuronectiformes.
Received December 1, 1997; accepted June 30, 1998. 相似文献
98.
Corrado Spadafora 《BioEssays : news and reviews in molecular, cellular and developmental biology》1998,20(11):955-964
Sperm cells from a variety of species share the spontaneous ability to take up foreign DNA. That feature has been exploited to generate genetically modified animals with variable efficiency in different species. An unexpectedly large set of factors appears to modulate the interaction of sperm cells with exogenous DNA. The binding is mediated by specific DNA-binding proteins and is antagonized by an inhibitory factor in the seminal fluid. A portion of sperm-bound DNA is internalized in nuclei, a process mediated by CD4 molecules. Sperm interaction with foreign DNA triggers endogenous nuclease(s) that cleaves both the exogenous and the genomic DNA, eventually leading to a cell death process which resembles apoptosis. Internalized foreign DNA sequences reach the nuclear matrix and undergo recombination with chromosomal DNA. From these studies, a surprising network of metabolic functions is beginning to emerge in mature spermatozoa, which are normally repressed and are specifically activated upon exposure to appropriate stimuli. BioEssays 20:955–964, 1998. © 1998 John Wiley & Sons, Inc. 相似文献
99.
To compare the behavioral effects of sleep‐loss sleepiness (performance impairment due to sleep loss) and sleep inertia (period of impaired performance that follows awakening), mean response latencies and number of lapses from a visual simple reaction‐time task were analyzed. Three experimental conditions were designed to manipulate sleepiness and sleep‐inertia levels: uninterrupted sleep, partial sleep reduction, and total sleep deprivation. Each condition included two consecutive nights (the first always a night of uninterrupted sleep, and the second either a night of uninterrupted sleep, a night when sleep was reduced to 3 h, or a night of total sleep deprivation), as well as two days in which performance was assessed at 10 different time points (08:00, 08:30, 09:00, 09:30, 10:00, 11:00, 14:00, 17:00, 20:00, and 23:00 h). From 08:00 to 09:00 h, reaction times in the partial sleep‐reduction and total sleep‐deprivation conditions were at a similar level and were slower than those observed in the uninterrupted sleep condition. In the same time period, the frequency of lapses in the total sleep‐deprivation condition was higher than in the partial sleep‐reduction condition, while this latter condition never differed from the uninterrupted sleep condition. The results indicate that both sleep inertia and sleep‐loss sleepiness lead to an increase in response latencies, but only extreme sleepiness leads to an increase in lapse frequency. We conclude that while reaction times slow as a result of both sleep inertia and sleep‐loss sleepiness, lapses appear to be a specific feature of sleep‐loss sleepiness. 相似文献
100.
Effendy Corrado Di Nicola Brian W. Skelton Allan H. White 《Inorganica chimica acta》2005,358(3):763-795
Single crystal X-ray structural characterizations are recorded for a wide range of adducts of the form MX:dppx (1:1)(n), M = silver(I) (predominantly), copper(I), X = simple (pseudo-) halide or oxy-anion (the latter spanning, where accessible, perchlorate, nitrate, carboxylate - a range of increasing basicity), dppx=bis(diphenylphosphino)alkane, Ph2P(CH2)xPPh2, x = 3-6. Adducts are defined of two binuclear forms: (i) [LM(μ-X)2L], with each ligand chelating a single metal atom, and (ii) [M(μ-X)2(μ-(P-L-P′))2M′] where both ligands L and halides bridge the two metal atoms; a few adducts are defined as polymers, the ligands connecting M(μ-X)2M′ kernels, this motif persisting in all forms. Synthetic procedures for all adducts have been reported. All compounds have been characterized both in solution (1H, 13C, 31P NMR, ESI MS) and in the solid state (IR). 相似文献