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1.
Infectious diseases remain one of the main causes of death and economic losses in animals despite the fact that prophylactic vaccination has been extremely successful in disease prevention. New effective viral, bacterial and parasitic vaccines are needed, but unfortunately production costs still remain prohibitive. In this respect plants can offer a valid alternative. Production of antigenic proteins in plants relies on a well developed and proven technology, several expression platforms are available and many different plant species can be utilized. Plant based veterinary vaccine studies have addressed protection issues in model animals and, more interestingly, some of them have examined the relevant challenge model in the specific species of interest. A general overview of the topic will be outlined together with a few selected promising examples.  相似文献   
2.
A total of 106 samples taken from natural Argentinean populations of the weedy Solanum elaeagnifolium (subgenus Leptostemonum) were studied cytologically to understand the impact of the different ploidy levels in its distribution and origin. Classical Feulgen staining was employed to determine mitotic chromosome numbers in all samples. 2C nuclear DNA content was determined by means of PI flow cytometry in eight samples of different ploidy levels. Principal component analysis and GIS tools were employed to compare altitude, annual precipitation and annual mean temperature among accessions. Three cytotypes were found: diploid (2n?=?24) which is widespread, tetraploid (2n?=?48) centered in western and southern Argentina, and hexaploid (2n?=?72) which predominates in central Argentina extending as well to the east. The annual precipitation is significantly different between tetraploids and hexaploids. Cx-values ranged from 1.231 to 1.275?pg, with statistical differences (of about 24.5–50.9?Mbp, p?≤?0.05) among accessions. Diploids are the most widespread cytotype and have adapted to a number of very different habitats. Tetraploids live in arid or semi-arid regions with a mean annual rainfall less than 500?mm. Hexaploids are successful in colonizing wetter areas, where no tetraploids were found. Thus, the distribution of cytotypes may be associated with habitat differences, particularly soil moisture. The observed cytotype pattern and the differences in DNA content suggest multiple places of origin for the polyploidy of S. elaeagnifolium in Argentina.  相似文献   
3.
The purpose of our study was to investigate changes in immunological parameters induced by weaning stress (including milk restriction) in calves. Fifteen Holstein calves were subjected to weaning at 6 weeks of age. Blood samples were collected at -14, -7, -2, 1, 3, and 5 days post-weaning (DPW; 0 DPW = 42 days). Weaning caused significant (p < 0.01) increases in the neutrophil (NE):lymphocyte (LY) ratio at 5 DPW with a significant (p < 0.05) reduction of LYs. The concentration of acute-phase proteins (haptoglobin and serum amyloid A) also increased significantly (p < 0.05) at 3 and 5 DPW compared to -2 DPW. Levels of the iron-binding protein lactoferrin decreased significantly (p < 0.05) after weaning. Serum tumor necrosis factor-α and cortisol levels were elevated (p < 0.05) at 3 DPW, while those of serum interferon-γ decreased (p < 0.05) at 1 and 3 DPW compared to levels observed before weaning. Weaning significantly (p < 0.05) decreased the percentage of CD25+ T cells in the peripheral blood. In conclusion, weaning stress affected the NE:LY ratio along with the levels of acute phase proteins, lactoferrin, cortisol, and inflammatory cytokines in the peripheral blood of calves. Weaning stress may induce an acute phase response possibly through the elevation of cortisol production and modulation of inflammatory cytokines.  相似文献   
4.
This study was conducted to evaluate the supplementation of glutamic acid(Glu)to reduced protein diets on the performance of weanling pigs.One hundred and eighty crossbred weanling pigs([YorkshireLandrace]Duroc,21 d old)having similar body weight(BW)of 6.45 kg were randomly allotted to 1 of 6 dietary treatments(5 pigs per pen[2 barrows and 3 gilts];6 pens per treatment)based on BW and sex during a 6-week trial.Dietary treatments consisted of positive control(PC)diet formulated to have 226.9,205.6,and 188.8 g crude protein(CP)during phases 1,2,and 3,respectively,and negative control(NC)diets with 20 g CP reduction from PC diets and addition of Glu with increasing levels,resulting in the calculated Lys-to-Glu ratios of 1:2.25,1:2.30.1:2.35,1:2.40,and 1:2.45,designated as NC,NC1,NC2,NC3,and NC4,respectively.The BW of pigs receiving PC diet was higher(P<0.05)than those receiving NC diet at d 7,21 and 42.A higher(P<0.05)average daily gain(ADG)from d 1 to 7,8 to 21,22 to 42 and during the overall experiment period was observed in pigs fed PC than NC diet.Pigs fed NC diets including the graded level of Glu linearly increased(P<0.05)BW at d 42,ADG and gain-to-feed ratio(G:F)during the overall experimental period.In addition,trends in linear increase in BW(P=0.056)at d 7 and ADG from d 1 to 7 and d 22 to 42(linear effect,P=0.081,P=0.058 respectively)were observed.A tendency in the linear increment of NH3(P=0.082)at d 21 and linear reduction in methyl mercaptans(P=0.054)emission at d 42 was observed in pigs fed NC diets supplemented with graded level of Glu.In conclusion,supplementing the reduced protein diet with Glu enhanced the growth performance in weanling pigs suggesting that supplementation of Glu can compensate the reduction of 2%CP in the basal diets.  相似文献   
5.
This opinion article expresses two key viewpoints regarding the options for Association of South‐East Asian Nations (ASEAN) universities in pursuit of fulfilling the demand for greater research visibility and academic reputation. The first viewpoint outlines the importance of promoting research collaboration among ASEAN researchers and their international peers in increasing the visibility and impact of ASEAN research. The second viewpoint examines the ASEAN research characteristics, the challenges and existing best practices of its journal publishing landscape, the potential role of non‐ASEAN international journals in improving the profile of ASEAN research and explores the needs and benefits of establishing an ASEAN Integrated Journal Publishing Network (IJPN). It is through these combined approaches, we believe, that effective policy change, the standardisation of publishing structure, procedures, and systems to drive journal development, improvement of journal quality, and establishment of a consistent framework for measuring researcher performance will result. This article also includes a proposal for the IJPN structure and implementation plan, and highlights the key benefits of taking a collaborative approach to achieving this common goal.  相似文献   
6.
A new dimeric aporphine, artabotrysine along with five known compounds was isolated from the roots of Artabotrys spinosus. Their structures were fully established on the basis of spectral evidence. All isolated compounds were evaluated for their cytotoxicity on HeLa and KB cells.  相似文献   
7.
Climate change is one of the major challenges for ecosystem conservation. One of the most vulnerable areas to climate change is the Mediterranean Basin which is expected to suffer important changes in temperature and precipitation in the next few decades, leading to a warmer and dryer climate. Therefore, it is necessary to determine species-specific responses to increased drought to predict possible future changes in the structure and composition of Mediterranean forests, as well as to identify appropriate management strategies to mitigate these effects.The main aim of this study has been to experimentally simulate the effects of a 15% reduction in annual rainfall on the survival and growth of two co-occurring Mediterranean oaks with contrasting leaf-habit (the evergreen Quercus ilex spp. ilex and the winter-deciduous Quercus cerrioides) and, to assess whether traditional selective thinning carried out in these mixed oak coppices (i.e. selection of one to few stems per stump) can modify the consequences of rainfall reduction.Soil moisture decreased under the rainfall reduction level while it increased in the thinned plots. Reduced rainfall did not influence tree mortality, but did lead to species-specific effects on height growth: no changes were observed in Q. ilex while height growth rate of Q. cerrioides decreased (c.a. 20%). Selective thinning improved tree growth (c.a. 50%) in stands both under natural and, and to a lesser extent, under reduced rainfall conditions. Nevertheless, the positive effects of thinning rapidly declined during our three years experiment, probably because the vigorous resprouting of thinned stumps.Our results show that the forecasted reduction in annual rainfall for the Western Mediterranean Basin can constrain the growth of some deciduous oaks in mixed oak coppices. Traditional selective thinning can increase soil moisture and encourage tree growth, thus partially mitigating this effect. However, the transient results observed in this experiment suggest the need to reconsider the intensity and the frequency of this traditional management practice in light of new climatic scenarios.  相似文献   
8.
A new 1-azaanthraquinone, named laoticuzanone A (1), and a synthetically known 3-methyl-1H-1-azaanthracene-2,9,10-trione (2), together with four known compounds, Griffithazanone A (3), methyl sinapate (4), methyl p-coumarate (5), and p-hydroxyphenylethyl p-coumarate (6) were isolated from the stems of Goniothalamus laoticus. Their structures were established on the basis of spectroscopic data as well as comparisons with the previous literature data. Compound 1 showed the highest cytotoxicity against KB and HeLa cells with IC50 values of 0.68 and 0.50 μg/ml, respectively.  相似文献   
9.
Parents and progenies genetic diversity, and male and female contributions to the seed crop were assessed in three experimental Prunus avium seed orchards. Collected data were used to compare different effective population sizes, based on phenological, seed crop and paternity analysis. Our results did not show any difference of genetic diversity between parents and progenies. A limited pollen pollution was detected. We showed that distance and coflowering among clones had a significant effect on effective pollination, and a significant effect of the production of flowers was revealed in one of the seed orchards. Our study also revealed a quite low number of effective size of fathers per mother, but high effective sizes of mothers, fathers and parents at the level of the seed orchard. Finally, the calculation of effective size of mothers, fathers and parents was not highly modified when having the complete information based on the paternity analysis.  相似文献   
10.
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