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11.
The aim of the present study was to evaluate the effect of trace mineral nutrition on sow performance, mineral content, and intestinal gene expression of neonate piglets when inorganic mineral sources (ITM) were partially replaced by their organic mineral (OTM) counterparts. At 35 d postmating, under commercial conditions, a total of 240 hyperprolific multiparous sows were allocated into three experimental diets: 1) ITM: with Zn, Cu, and Mn at 80, 15, and 60 mg/kg, respectively; 2) partial replacement trace mineral source (Replace): with a 30 % replacement of ITM by OTM, resulting in ITM + OTM supplementation of Zn (56 + 24 mg/kg), Cu (10.5 + 4.5 mg/kg), and Mn (42 + 18 mg/kg); and 3) Reduce and replace mineral source (R&R): reducing a 50% of the ITM source of Zn (40 + 24 mg/kg), Cu (7.5 + 4.5 mg/kg), and Mn (30 + 18 mg/kg). At farrowing, 40 piglets were selected, based on birth weight (light: <800 g, and average: >1,200 g), for sampling. Since the present study aimed to reflect results under commercial conditions, it was difficult to get an equal parity number between the experimental diets. Overall, no differences between experimental diets on sow reproductive performance were observed. Light piglets had a lower mineral content (P < 0.05) and a downregulation of several genes (P < 0.10) involved in physiological functions compared with their average littermates. Neonate piglets born from Replace sows had an upregulation of genes involved in functions like immunity and gut barrier, compared with those born from ITM sows (P < 0.10), particularly in light piglets. In conclusion, the partial replacement of ITM by their OTM counterparts represents an alternative to the totally inorganic supplementation with improvements on neonate piglet gene expression, particularly in the smallest piglets of the litter. The lower trace mineral storage together with the greater downregulation of gut health genes exposed the immaturity and vulnerability of small piglets.  相似文献   
12.
This study reports the immunohistochemical localization and distribution of orexin A and B-like and their receptors-like peptides in the gastroenteric tract of chicken. The immunoreactivity is distributed in endocrine cells, nerve fibers and neurons, both in the stomach and intestine, and shows a discrete conformity with the data till now reported for Mammals. Our study suggests a possible participation of orexin-like peptides in the modulation of chicken gastroenteric activities and the preservation of their main distribution compared to Mammals. Western blot analysis has confirmed the presence of prepro-orexin and both receptors in the examined tissues.  相似文献   
13.
  1. Genetic information is crucial for the conservation of Dipturus oxyrinchus (Linnaeus, 1758), a threatened large skate with declining populations over most of its geographical range. The main aim of the present study was to investigate the genetic structure, connectivity and demographic history of the longnosed skate in Sardinia (western Mediterranean Sea).
  2. Patterns of population structure were assessed in 175 specimens from six sampling sites. Variation in two mitochondrial genes (cytochrome c oxidase subunit I (COI) and control region) highlighted high genetic diversity and low but significant genetic differentiation among sites, which clustered into three groups corresponding to the north‐west, north‐east and south Sardinian coasts.
  3. The observed genetic structuring could presumably depend on a combination of past geological events, contemporary restrictions to dispersal and biological characteristics of the species (e.g. site‐fidelity, no pelagic larval stage, limited dispersal of juveniles and/or adults).
  4. Demographic analyses showed signs of past population expansion, but substantial current stability of Sardinian populations. From a conservation perspective, these results are encouraging, and indicate that Sardinian populations are still large and stable, and seem not to have suffered negative side‐effects from the ever‐growing fishing pressure in the region.
  5. The occurrence of genetic structuring strongly supported the close monitoring of populations to identify any erosion of their gene pool, and high genetic variability of the Sardinian D. oxyrinchus populations could thus represent priority populations for conservation purposes, providing potential sources for recolonization in cases of local extinctions in other areas of the distribution range of the species.
  6. When the sequences from Sardinia were compared with those available from other areas, the data seem to exclude the possibility that the Atlantic and Mediterranean host totally isolated populations or even different species, as recently suggested. However, additional markers and a larger sampling sites are needed to confirm these findings.
  相似文献   
14.
15.
  1. Isoëtes sabatina is the rarest aquatic quillwort in Europe. Although recently found (2013) in Lake Bracciano (central Italy), the species is just one step away from extinction with an estimated population not exceeding 400 individuals and a spatial range of a few hundred square metres.
  2. Lake Bracciano is a deep, oligo-mesotrophic Mediterranean volcanic lake that has been subjected to human activities. From January to October 2017, the lake experienced a dramatic water level decrease (up to −1.50 m), which significantly affected the littoral zone and the habitat of I. sabatina.
  3. To improve the chances of survival of I. sabatina, the first eco-taxonomic investigation on this species was carried out to describe its genetic distinctness, physical and chemical requirements and companion species.
  4. The phylogenetic position of I. sabatina was investigated by applying standard DNA barcoding methods. Simultaneously, during summer 2019, the physical and chemical features of water and sediments of the I. sabatina population and five small Alpine lakes colonized by Isoëtes echinospora – a supposed close relative – were characterized. These data were then compared with the available data on the trophic requirements of the target obligate aquatic Isoëtes, together with Isoëtes lacustris and Isoëtes malinverniana.
  5. The present survey confirmed the taxonomic and ecological distinctness of I. sabatina – providing the first evidence of genetic differentiation from I. echinospora. Isoëtes sabatina grows in waters with temperature, conductivity and total alkalinity up to 30°C, 561 μS cm−1 and 3.45 meq L−1, respectively.
  6. The edaphic requirements of I. sabatina confirm its outstanding conservation value, and this study offers a basic understanding of how to prevent its extinction. Now, all possible actions must be taken immediately to save this species.
  相似文献   
16.
Carcass and flesh morphometric, reological and chemical traits of triploid (3n) and diploid (2n) shi drum (Umbrina cirrosa L.) were evaluated through 7 months. Three age groups, 17‐, 21‐ and 24‐month‐old fish, were investigated. The effects of ploidy were statistically evaluated and the weight of fish was included in the model as a covariate because triploids grew less than diploids. As expected, fish weight was found to be significantly correlated with all the investigated morphometric traits, but showed a negative correlation with some chemical (pH) and colour traits (lightness) of raw fillet. In comparison with controls, triploid shi drums were characterized by different morphological traits that involved a slender body shape. In triploids, a reduction in condition factor, backbone weight, dressing index and an increase in the agility index were also recorded. When the commercial size (i.e. over 300 g) was achieved, triploids exhibited larger coelomatic and fillet (dorsal white muscle) fat deposition than diploids. Among reological traits, colour and texture were affected by ploidy; raw fillet lightness and cooked flesh tenderness were higher among triploids in all the investigated age groups. As fish were fed with a restricted feeding regimen, fillet fat deposition was supposed to be limited. Thus, the effects of ploidy on reological traits may be only partially explained by lipid fillet amount and are supposed to be more related to different fibre muscle architecture.  相似文献   
17.
Nitrated Polycyclic Aromatic Hydrocarbons (NPAH) were determined in the suspended particulates collected in São Paulo (Brazil) and three other cities lying in the São Paulo State, (namely, Araraquara, Piracicaba and Paulínia), during August 2002 and July 2003. São Paulo samples represented a big difference between two groups of days, one of which characterized by heavy injection of pollutants released by industrial and agricultural activities. Most NPAH congeners identified in the atmosphere were among those usually associated to diesel exhaust, with the three important exceptions of 2-nitrofluoranthene, 2- and 4-nitropyrene. Daytime reactions seemed to promote decomposition of primary fluoranthene and pyrene. Trends of NPAH at all sites seemed to be associated to regional transport of polluted air through air masses passing over sugar cane plantations of São Paulo State.  相似文献   
18.
Biphenyl and several plant secondary metabolites (PSM) (carvone, isoprene, limonene, naringin, and coumarin) and surfactant (hydroxypropyl-β-cyclodextrin, (HP-β-CD)) have been shown to improve aerobic polychlorinated biphenyl (PCB) removal by several bacterial species. The objective of this study was to determine whether these treatments also affect PCB removal and microbial community structure in a high organic matter soil (Pahokee soil series with 67% organic matter) and low organic matter soil (Woolper soil series with 6% organic matter), as determined by monitoring changes in PCB levels and phospholipid fatty acids (PLFA) profiles in laboratory microcosms amended with these compounds. Biphenyl enhanced di-chlorinated and tri-chlorinated biphenyl removal in both soils, but PSM did not improve removal of these congeners. On the contrary, HP-β-CD decreased PCB removal when used in combination with biphenyl. Two-way analysis of variance indicated that HP-β-CD significantly increased tetra- and penta-chlorinated biphenyl removal from the high organic matter soil, but not from the low organic matter soil. Principal components analysis of PLFA data indicated that HP-β-CD increased proportions of 18:1ω7c associated with Gram-negative bacteria, but decreased 10me16 and 10me17 lipid associated with Gram-positive bacteria, while biphenyl and PSMs had no detectable effects on soil microbial communities. PCB removal was not correlated to any PLFA. In conclusion, PSM previously shown to enhance PCB removal in soil-free systems were not effective in two divergent soils evaluated in this study, and HP-β-CB had increase, decrease, or no effect on PCB removal depending on types of PCB congeners, soils, and co-amendments.  相似文献   
19.
The prevailing environmental conditions, temperature in particular, drive seasonal changes both in leaf development and stomatal characteristics. In order to ascertain the effect of increases in climatic water deficit on some leaf and stomatal parameters under field conditions, a study was carried out on two sets of leaves (spring and summer) on a large sample of Amygdalus communis L. cultivars in comparison with several Amygdalus webbii Spach seedlings, a species more adapted to arid environments and probable ancestor of cultivated almonds. Observations were performed between spring and summer of a particularly hot season. The results showed a significant and general reduction of both leaf area and stomatal frequency and an increase in stomatal size. Nevertheless, there were evident differences between cultivated and wild almonds. A stronger reduction of leaf area was observed in A. webbii (−31%) with respect to A. communis (−14%); on the contrary, the latter reduced stomatal frequency more than the former (−25% and −19%, respectively). The examined cultivated almonds, in response to the increase in climatic water deficit, tended to arrange their stomatal structures like those of wild almonds. Finally, increasing the climatic water deficit, the slope of the linear regressions between stomatal frequency and size did not change in either species, leading to a better understanding of the mechanisms of almond acclimation to environmental stresses.  相似文献   
20.
Two structurally related organophosphorous insecticides, dichlorvos and trichlorfon, and their main metabolite dichloroacetaldehyde, were assayed for their ability to induce DNA repair, detected as unscheduled DNA synthesis in human epithelial-like cell (EUE) cultures in vitro. A dose-response relationship was found for treatment with the two pesticides, but negative results were obtained with dichloroacetaldehyde. Tests for induction of gene mutation, as ouabain resistance in Chinese hamster cells (V79), failed to show any mutagenic activity by these compounds.  相似文献   
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