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21.
Sex attractants were established for one Brachodidae, three Choreutidae and two Tineidae moth species during field screening tests with (2E,13Z)-octadecadien-1-al, (2E,13Z)-, (3E,13Z)-, (3Z,13Z)-octadecadien-1-ols and their acetates (2E,13Z-18:Ald, 2E,13Z-, 3E,13Z-, 3Z,13Z-18:OH/OAc) as well as of binary mixtures of these compounds in West-Kazakhstan and Lithuania. Males of Brachodes appendiculata were attracted by 3E,13Z-18:OAc, Prochoreutis ultimana and P. myllerana by 2E,13Z-18:OH, Monopis palidella by 2E,13Z-18:Ald and Triaxomera fulvimitrella by binary mixtures of 3Z,13Z-18:OAc with either 3E,13Z-18:OH in the ratio of 5:5 or 3Z,13Z-18:OH in the ratio of 9:1 (v/v). The 3-component mixture composed of 2E,13Z-18:OH, 3Z,13Z-18:OH and 2E,13Z-18:Ald in the ratio 1:1:1 was developed to attract Prochoreutis sehestediana males. Attraction antagonists for B. appendiculata, P. ultimana and M. palidella were shown.  相似文献   
22.
The formation of four Cu(II)-xylitol complexes was observed in aqueous alkaline solutions (11.0< or =pH< or =14.0, I=1.0, 20 degrees C) by means of direct current polarography and VIS spectrophotometry. Mononuclear hydroxy complexes, CuXyl(OH)- (log beta=17.7 +/- 0.5), CuXyl(OH)2(2-) (log beta=20.2 +/- 0.3) and CuXyl2(OH)2(4-) (log beta=22.4 +/- 0.3), are formed at high ligand-to-metal ratios (L:M> or =10), whereas dinuclear complex Cu2Xyl (log beta=29.2 +/- 0.3) is the predominant species at low ligand-to-metal ratio (L:M=0.5). Diffusion coefficients and molar absorptivities of the complex species were determined. pH variable 13C NMR suggested that pKa values of xylitol are rather similar and equal to 13.8 +/- 0.2, 13.9 +/- 0.1 and 13.9 +/- 0.2 for OH-groups adjacent to (C-1,C-5), (C-3) and (C-2,C-4) carbon atoms, respectively.  相似文献   
23.
The calling activity of virgin Phyllonorycter junoniella (Z.) females under a cycling thermal regime differed from that under constant temperature in the following ways: the percentage of females calling at the morning activity peak was increased; the morning period of calling activity was prolonged; the total period of calling activity of an individual female was increased; an extra peak of activity occurred at the end of the photophase, and females changed the calling pattern during the active period. We assume that the occurrence of two calling peaks and the extension of the calling period might be adaptive for a Ph. junoniella species with a sex ratio strongly shifted towards females (8:1 females:males), as it could lead to an increased proportion of females mated.  相似文献   
24.
A statistical approach is presented for selection of best performing lines for commercial release and best parents for future breeding programs from standard agronomic trials. The method involves the partitioning of the genetic effect of a line into additive and non-additive effects using pedigree based inter-line relationships, in a similar manner to that used in animal breeding. A difference is the ability to estimate non-additive effects. Line performance can be assessed by an overall genetic line effect with greater accuracy than when ignoring pedigree information and the additive effects are predicted breeding values. A generalized definition of heritability is developed to account for the complex models presented.  相似文献   
25.
A combination of enclosure nutrient enrichment experiments and historical data analysis was used to identify the factors controlling seasonal dynamics and competition of the phytoplankton community in the Curonian lagoon (Southeast Baltic Sea). Experiments using different nutrient (N, P and Si) manipulations were performed in 10-l enclosures for 48 h. Changes in chlorophyll a concentrations, inorganic nutrient concentrations, and plankton cell density were monitored. Results revealed that phytoplankton development in the lagoon is strongly affected by ambient physical factors (wind, temperature). Nutrient limitation, however, also plays an important role in seasonal succession mechanisms showing quite distinct seasonal development patterns. Based on the data, available phytoplankton seasonal succession in the Curonian lagoon could be described as composed by three phases corresponding to different domination and regulatory mechanisms.  相似文献   
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27.
During 2009 and 2010 samples from 251 wild birds (37 species) from nine sites of Slovakia were collected. Blood samples were tested for Plasmodium, Haemoproteus, and Leucocytozoon spp. parasites using both PCR-based and microscopy techniques. The overall prevalence of infection was 56.6%, while prevalence of Haemoproteus a Plasmodium spp. (were evaluated separately from Leucocytozoon) was 46.6% and the prevalence of Leucocytozoon spp. was 33.9%. After microscopic examination of stained blood smears the identification of haemoproteids was performed. There were 14 species of three genera identified, i.e., Haemoproteus parabelopolskyi, H. belopolskyi, H. magnus, H. fallisi, H. fringillae, H. balmorali, H. dolniki, H. tartakovskyi, H. lanii, Leucocytozoon majoris, L. dubreuili, Plasmodium vaughani, P. relictum, P. circumflexum. Except for H. fringillae, H. balmorali, H. belopolskyi, L. majoris and L. dubreuili, the mentioned species of parasites were recorded for the first time in Slovakia.  相似文献   
28.
Forest patches with high biological value are protected as woodland key habitats (WKH), which are identified by the presence of forest structures and indicator species. However, management for conservation needs to consider also managed forests as habitats for species. In this respect, there is a need to set quantitative targets for species and structures at different landscape scales. Due to non-intensive methods of forest management used prior to 1940 in Latvia, it might be expected that large areas of forest have developed structures that can support many species characteristic of natural forests. The aim of the study was to create a model that best described the richness of bryophyte species that are characteristic of natural forests, using forest structures as explanatory factors. The structures and bryophyte communities on living trees and coarse woody debris (CWD) were described in plots along transects blindly placed in areas dominated by State forests under commercial management. Explanatory variables related to tree species composition and tree size explained 54% of the variation in WKH indicator species richness on living trees. The best explanatory factors were maximum diameter of deciduous tree species and CWD. Low richness of total bryophyte and indicator species was found on dead wood, and the amount of variation in bryophyte species richness on CWD explained by explanatory variables was low. The study indicates the importance of deciduous tree substrate in managed forests in maintaining the spatial continuity of epiphytic species diversity. However, the forests in the managed forest landscape did not support high diversity of epixylic species, even in the WKHs, due to low diversity of suitable dead wood substrate.  相似文献   
29.
Recent advances in genomics technologies have spurred unprecedented efforts in genome and exome re-sequencing aiming to unravel the genetic component of rare and complex disorders. While in rare disorders this allowed the identification of novel causal genes, the missing heritability paradox in complex diseases remains so far elusive. Despite rapid advances of next-generation sequencing, both the technology and the analysis of the data it produces are in its infancy. At present there is abundant knowledge pertaining to the role of rare single nucleotide variants (SNVs) in rare disorders and of common SNVs in common disorders. Although the 1,000 genome project has clearly highlighted the prevalence of rare variants and more complex variants (e.g. insertions, deletions), their role in disease is as yet far from elucidated.We set out to analyse the properties of sequence variants identified in a comprehensive collection of exome re-sequencing studies performed on samples from patients affected by a broad range of complex and rare diseases (N = 173). Given the known potential for Loss of Function (LoF) variants to be false positive, we performed an extensive validation of the common, rare and private LoF variants identified, which indicated that most of the private and rare variants identified were indeed true, while common novel variants had a significantly higher false positive rate. Our results indicated a strong enrichment of very low-frequency insertion/deletion variants, so far under-investigated, which might be difficult to capture with low coverage and imputation approaches and for which most of study designs would be under-powered. These insertions and deletions might play a significant role in disease genetics, contributing specifically to the underlining rare and private variation predicted to be discovered through next generation sequencing.  相似文献   
30.
Woodland key habitat (WKH) inventories have been conducted in northern European countries, with the aim to create networks of minimally disturbed forest stands for protection. The goal of national forest inventory is to provide information relevant to forest management, such as on forest types, trees species composition, age structure and wood volume. The aim of this study was to link these two inventory databases to identify districts of Latvia most deficient in connectivity and habitat quality, in order to prioritize districts needing conservation effort. As an example, the area of deciduous forest with nemoral tree species (oak, ash, lime, maple and elm) and aspen was chosen. These forests provide habitat for a specific community of epiphytes. Using information in the WKH database, habitat quality in different districts of Latvia was estimated by the frequencies of occurrence of structural elements and selected indicator epiphyte species in nemoral tree species and aspen WKHs. Using digital data in the national forest inventory database, fragmentation metrics were determined for forests that, according to age and tree species composition, could potentially be nemoral tree and aspen WKHs. On a regional level, the lowest habitat quality in WKH occurred in districts that had the least fragmentation of potential WKH forest. In the less fragmented areas, the habitat quality of the existing WKH will likely increase in the future, and could be promoted by management to create structural elements typical of natural forests. The districts with the most fragmented nemoral and aspen forests, contained WKHs with the best habitat quality. A focus on protection should be given to these stands as they are the most likely to support source populations, and there is a need to improve spatial continuity of suitable tree substrate in these areas.  相似文献   
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