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21.
This work evaluated the preference of Ascia monuste orseis among 29 cultivars of collard greens through free- and no-choice assays using female adults (attractiveness and oviposition) and third-instar larvae (feeding preference), in both laboratory and greenhouse conditions. In free-choice tests with female adults, the L, V, Y, H, A, and Z cultivars produced oviposition non-preference in butterflies. Cultivars R, P, C, and D produced feeding non-preference in third-instar larvae of A. monuste orseis in free- and no-choice tests. Our findings may be useful for genetic improvement focusing on the development of B. oleracea var. acephala cultivars resistant to A. monuste orseis.  相似文献   
22.
Water relations, leaf gas exchange, chlorophyll a fluorescence, light canopy transmittance, leaf photosynthetic pigments and metabolites and fruit quality indices of cherry cultivars 'Burlat', 'Summit' and 'Van' growing on five rootstocks with differing size-controlling potentials that decrease in the order: Prunus avium L. > CAB 11E > Maxma 14 > Gisela 5 > Edabriz, were studied during 2002 and 2003. Rootstock genotype affected all physiological parameters. Cherry cultivars grafted on invigorating rootstocks had higher values of midday stem water potential (Psi(MD)), net CO(2) assimilation rate (A), stomatal conductance (g(s)), intercellular CO(2) concentration (C(i)) and maximum photochemical efficiency of photosystem II (PSII) (F(v)/F(m)) than cultivars grafted on dwarfing rootstocks. The Psi(MD) was positively correlated with A, g(s) and C(i). Moreover, A was positively correlated with g(s), and the slopes of the linear regression increased from invigorating to dwarfing rootstocks, indicating a stronger regulation of photosynthesis by stomatal aperture in trees on dwarfing Edabriz and Gisela 5. The effect of rootstock genotype was also statistically significant for leaf photosynthetic pigments, whereas metabolite concentrations and fruit physicochemical characteristics were more dependent on cultivar genotype. Among cultivars, 'Burlat' leaves had the lowest concentrations of photosynthetic pigments, but were richest in total soluble sugars, starch and total phenols. Compared with the other cultivars, 'Summit' had heavier fruits, independent of the rootstock. 'Burlat' cherries were less firm and had lower concentrations of soluble sugars and a lower titratable acidity than 'Van' cherries. Nevertheless, 'Van' cherries had lower lightness, chroma and hue angle, representing redder and darker cherries, compared with 'Summit' fruits. In general, Psi(MD) was positively correlated with fruit mass and A was negatively correlated with lightness and chroma. These results demonstrate that: (1) water relations and photosynthesis of sweet cherry tree are mainly influenced by the rootstock genotype; (2) different physicochemical characteristics observed in cherries of the three cultivars suggest that regulation of fruit quality was mainly dependent on the cultivar genotype, although the different size-controlling rootstocks also had a significant effect.  相似文献   
23.
This study aimed to characterize the annual reproductive cycle of Santa Inês sheep in the Fluminense lowland region (latitude 22° 27′ 45″ south, Rio de Janeiro, Brazil) between September 2011 and August 2012. Ten ewes were maintained in a semi-intensive system under natural photoperiods with access to pasture and shelter. Blood samples were collected every 2 weeks to determine plasma progesterone concentrations. The body condition score (BCS) was determined each month. There was no seasonal variation in the plasma progesterone concentration from the months of September to January, April, and May to August. In the months of February and April, the plasma hormone levels were higher than August to November. Seventy percent (7/10) of the sheep studied had short seasonal anestrus. The periods of anestrus were concentrated between the months of September and December (spring season) in 85.7 % (6/7) of the cases evaluated. In these cases, 57.1 % (4/7) also had short periods of reproductive inactivity during other months of the year. The progesterone values obtained in the spring corroborate the higher reproductive anestrus observed in this season. Higher plasma progesterone values were found in summer and autumn with reduction in the winter to lower values in the spring. No changes in the BCS during the study period were observed. Under the studied conditions, the Santa Inês sheep showed a low degree of reproductive seasonality. However, some individual ewes had seasonal anestrus during the spring. Further studies that include management techniques are needed to improve reproductive efficiency without hormone therapy in this breed under tropical conditions.  相似文献   
24.
Maize (Zea mays L.) is an important staple food crop in West and Central Africa (WCA). However, its production is constrained by drought. Knowledge and understanding of the genetics of hybrid performance under drought is invaluable in designing breeding strategies for improving maize yield. One hundred and fifty hybrids obtained by crossing 30 inbreds in sets using the North Carolina Design II plus six checks were evaluated under drought and well‐watered conditions for 2 years at three locations in Nigeria. The objectives of the studies were to (i) determine the mode of gene action controlling grain yield and other important agronomic traits of selected early inbred lines, (ii) examine the relationship between per se performance of inbreds and their hybrids and (iii) identify appropriate testers for maize breeding programmes in WCA. General combining ability (GCA) and specific combining ability (SCA) mean squares were significant (P < 0.01) for grain yield and other traits under the research environments. The GCA accounted for 64.5 % and 62.3 % of the total variation for grain yield under drought and well‐watered conditions, indicating that additive gene action largely controlled the inheritance of grain yield of the hybrids. Narrow‐sense heritability was 67 % for grain yield under drought and 49 % under well‐watered conditions. The correlations between traits of early‐maturing parental lines and their hybrids were significant (P < 0.01) under drought, well‐watered and across environments. Mid‐parent and better‐parent heterosis for grain yield were 45.3 % and 18.4 % under drought stress and 111.9 % and 102.6 % under well‐watered conditions. Inbreds TZEI 31, TZEI 17, TZEI 129 and TZEI 157 were identified as the best testers. Drought‐tolerant hybrids with superior performance under stress and non‐stress conditions could be obtained through the accumulation of favourable alleles for drought tolerance in both parental lines.  相似文献   
25.
Structural changes of alkali-treated rockfish protein isolate (AKPI) during frozen storage were elucidated using a Raman spectrometer and scanning electron microscope (SEM). The results were compared to conventional surimi (CS). No significant textural difference was noted between AKPI stored at pH 5.5 and 7.0. The strongest texture was found for AKPI frozen with cryoprotectants and CS, while the weakest texture was observed in AKPI frozen without cryoprotectants. SEM revealed the most discontinuity in gels of AKPI with no cryoprotectants and a more aggregated microstructure after storage at pH 5.5 than at neutral pH. Raman spectral analysis demonstrated refolding of AKPI by pH readjustment to 7.0, although the refolded structure was not identical to that before the pH shift. CS showed higher alpha-helix content (approximately 50%) than AKPI (approximately 20-30%). Frozen storage induced a decrease and an increase in the alpha-helix content of CS and AKPI samples, respectively. AKPIs were slightly less stable than CS during frozen storage.  相似文献   
26.
Soybean meal (SBM) inclusion in salmonid diets can lower feed cost, but dramatically reduces growth and feed utilization, and increases mortality in juvenile chinook salmon Oncorhynchus tshawytscha, due to diminished diet palatability and/or other adverse physiological effects exerted by antinutritional factors in SBM. The objective of this study was to investigate whether commercial Antarctic krill meal Euphausia superba or hydrolysates enzymatically produced from Pacific hake Merluccius productus could reverse the negative palatability effects of SBM inclusion in juvenile chinook salmon diets. Diets without SBM or with SBM and no added feed attractant were used as positive and negative control diets respectively. Incorporation of 2% krill meal or Alcalase®‐produced hydrolysates into SBM‐containing diets (20% of dry matter by isonitrogenous replacement of fishmeal) significantly (P < 0.05) increased feed intake, feed utilization, fish weight gain and thermal growth coefficient during a 5‐week trial. Nevertheless, the negative effects on fish performance incurred by dietary inclusion of 20% SBM could not be fully reversed, indicating that most of those effects were likely unrelated to palatability. This study demonstrates the potential for using Pacific hake hydrolysates as a dietary feed attractant for salmonid diets, and supports the need for further research to optimize its application for ideal fish performance.  相似文献   
27.
BACKGROUND: Four‐arm olfactometer bioassays were conducted to assess the behavioural responses of the adult maize weevil, Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae), to harvested seeds of host plants, i.e. white maize, yellow maize (Zea mays L.) and winter wheat (Triticum aestivum L.) (Poaceae), and non‐host plant materials, i.e. alligator pepper, Aframomum melegueta (Rosk) K. Schum (Zingiberaceae), rhizomes of ginger, Zingiber officinale (Roscoe) (Zingiberaceae), and West African black pepper, Piper guineense Thonn and Schum (Piperaceae). Additional bioassays with host plant volatiles were conducted in the presence of three doses of non‐host plant materials. RESULTS: Both sexes of the weevil showed strong attraction to maize and wheat seed volatiles, but were significantly repelled (P < 0.001) by odours from A. melegueta, Z. officinale and P. guineense. Furthermore, S. zeamais avoided maize and wheat seeds presented in combination with the non‐host plant material at 10% (w/w) and 33% (w/w) levels. CONCLUSIONS: A. melegueta, Z. officinale and P. guineense have the potential for use in the protection of stored grains by resource‐poor farmers with local access to these plants. Copyright © 2009 Society of Chemical Industry  相似文献   
28.
The objective of this study was to describe the dynamic changes in protein composition and protein abundance in amniotic and allantoic fluids from buffaloes during gestation. Amniotic and allantoic fluids were collected during the first, second and third trimesters of gestation. The foetuses were measured and weighed. Fluid samples were centrifuged at 800 g for 10 min and then at 10,000 g for 60 min at 4°C. The supernatant was collected to determine the total protein concentration. Based on total protein concentration, an aliquot (50 μg) was used for in‐solution tryptic digestion, and mass spectrometry analysis (nano‐LC‐MS/MS) was performed. A multivariate statistical analysis of the proteomic data was conducted. Across the different stages of buffalo gestation, fifty‐one proteins were found in the amniotic fluid, and twenty‐one were found in the allantoic fluid. A total of twelve proteins were common among the stages, and four presented significant differences (VIP score α > 1). Fibronectin and alpha‐1‐antiproteinase were more abundant in the amniotic fluid than in the allantoic fluid. Alpha‐2‐macroglobulin and alpha‐2‐HS‐glycoprotein were more abundant in the allantoic fluid than in the amniotic fluid. Alpha‐2‐macroglobulin participates in remodelling and growth of the uterus at beginning of the gestation (first trimester), and these findings indicate that can serve as a potential tool for the early diagnosis of pregnancy in buffaloes.  相似文献   
29.
  1. The short-beaked common dolphin is one of the most numerous cetacean species in the North-East Atlantic and plays a key functional role within the ecosystem as a top predator. However, in 2013, its conservation status for the European Marine Atlantic, under Article 17 of the Habitats Directive, was assessed as ‘Unfavourable-Inadequate’. Of key concern for this species is fishery bycatch, with pollution also being an issue. There are, however, major knowledge gaps concerning the extent of the effects of such pressures on the species.
  2. Implementation of national observer bycatch programmes and bycatch mitigation measures under EC Regulation 812/2004 has been important. The responsibility for this is currently being transferred to the EU fisheries Data Collection Framework and Technical Measures Framework, the potential advantages and disadvantages of which are discussed. Collection of data and samples through national stranding schemes in some countries has enabled assessments of life-history parameters, dietary requirements, and the effects of stressors such as pollutants.
  3. Nevertheless, in order to improve the conservation status of the North-East Atlantic population, a number of key actions are still required. These include the implementation of a species action plan, finalization of a management framework procedure for bycatch, and coordination between member states of monitoring programmes. It is important that there is monitoring of the state of the common dolphin population in the North-East Atlantic management unit through regular surveys spanning the range of the management unit, as well as continued assessment of the independent and interactive effects of multiple stressors. Above all, conservation status would be improved through application and enforcement of existing legislation in European waters.
  4. This paper provides a summary of the current state of our knowledge of common dolphins in the North-East Atlantic along with recommendations for conservation management that may also be relevant to the species in the Mediterranean Sea.
  相似文献   
30.
Purification of lactoferricin (Lfcin), a cationic antimicrobial peptide, was achieved by peptic digestion of food grade bovine lactoferrin (LF) followed by fractionation on an industrial grade cation exchange resin with stepwise salt gradient elution. The digest and eluted fractions were partially characterized by MALDI-ToF MS and N-terminal sequencing. A fraction eluted using phosphate buffer with 2.0 M NaCl contained predominantly two peptides with masses of 3196 and 3124 Da, which corresponded to the 26- and 25-amino acid peptides FKCRR WQWRM KKLGA PSITC VRRAF (A), containing the Lfcin sequence. Putative sequences of cationic peptides in other eluted fractions included FKNKS RSFQ, WRMKK LGAPS ITCVR RA, and GAPSI TCVRR AFALE CIRAI AEKKA. The iron saturation level of LF had no effect on the production of Lfcin. Nevertheless, the digestion of LF containing lower iron content led to the production of a higher quantity of low molecular weight cationic peptides. A two-step process using industrial grade cation exchange resin led to 35% recovery of Lfcin and also produced other cationic peptides with potential bioactive properties.  相似文献   
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