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Canine Lyme borreliosis may be caused by three Borrelia burgdorferi sensu lato genospecies. The prevalence of infection by Borrelia species was determined by nested polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) with the enzyme Fsp4H I in the blood of dogs naturally infested by ticks in an endemic region of Poland. Blood samples were collected from 98 dogs of various breeds, delivered to the Veterinary Clinic in Szczecin (northwestern Poland) for various reasons. Nested PCR revealed the presence of DNA characteristic of only 1 genospecies, i.e. B. burgdorferi sensu stricto (s.s.), in all PCR-positive samples. Digestion of PCR products from a fragment of the fla gene amplified with primers FLA1 and FLA2 gave only one band pattern consistent with the pattern obtained from sequence analysis of the fla gene from a reference isolate of B. burgdorferi s.s. GeHo (X15660) from GenBank.  相似文献   
94.
The aim of our studies was to determine the relation between temperature and the respiration rate of the forest soil organic layer along an altitudinal gradient while controlling the effects of the soil characteristics. The respiration rate was measured in laboratory conditions at different temperatures, 0, 10, 20, and 30°C, in samples collected in the Polish part of the Western Carpathians at 600, 800, 1,000, and 1,200 m above sea level from four different mountains, which were later treated as replicates. The increase in the average respiration rate between two consecutive temperatures was expressed as Q 10 coefficients. Among the nutrients measured in the soil organic layer, only the total organic N concentration significantly increased with elevation. The temperature effect was significant for both the respiration rate and the Q 10 values. The calculated Q 10 values were highest for the temperature range between 10 and 20°C, and the lowest values were obtained from the highest temperature range (20–30°C). The altitude effect was significant for the respiration rate but not for the Q 10 values, indicating that the temperature sensitivity of the soil respiration did not change much along the studied altitudinal gradient.  相似文献   
95.
A comparative study of potato leaf sesquiterpenes was carried out. GC, GC-MS, and NMR analyses were used to identify and quantify the sesquiterpenes in the leaf surfaces of 10 potato (Solanum tuberosum) varieties. Two sesquiterpene alcohols and 17 sesquiterpene hydrocarbons were identified and quantitatively determined. The distribution of the sesquiterpenes was found to be variety-specific. The sesquiterpene contents of the different potato varieties were subjected to cluster and principal component analyses. The eight potato varieties of the main chemotype cluster were dominated by beta-caryophyllene (9-148 ng/cm2), germacrene D (2-46 ng/cm2), germacrene D-4-ol (0.4-31 ng/cm2), beta-sesquiphellandrene (1-34 ng/cm2), and an unknown sesquiterpene alcohol III (0.2-37 ng/cm2). Chemometric classification distinguished two varieties, Mila and Vistula, from a major cluster. The Vistula variety was distinguished from the others by its high contents of beta-caryophyllene, alpha-humulene, germacrene D, and germacrene D-4-ol and the Mila variety by beta-elemene, trans-alpha-bergamotene, (Z)-beta-farnesene, (E)-beta-farnesene, trans-beta-bergamotene, beta-sesquiphellandrene, and unknown sesquiterpene alcohols I, II, III.  相似文献   
96.
Background, Goal and Scope   The aim of this study was to check the concentration of some elements in water samples collected near Pb-Zn mining and smelting works and comparison of the obtained data with results achieved for sediment samples originated from the same reservoirs. Objective   Here, 8 water samples and 3 bottom sediments collected from water reservoirs in the vicinity of 3 big Polish Pb-Zn smelters were analysed.Methods   Water analysis was performed after filtration through a 0.45 µm filter and pH adjustment to 2. For decomposition of dried sediment samples, microwave assisted digestion with total dissolution of silicate matrix was applied. The elements studied were determined using ICP-MS and ICP-OES methods. Results and Discussion   The concentrations of most studied elements in water samples were on the 0.X µg/L level, while only the contents of Tl, As, Mn, Cd, Pb and Sb in two water reservoirs were above the limits established for drinking water. The content of studied metals in sediments was in a wide range from X mg/kg (Se and Sb) to X000 mg/kg (Pb and Zn).Conclusions  and Recommendation. The study indicates that the impact of Tl, As, Cd, Cu, Mn, Pb, Zn, Se and Sb on bottom sediments is much more extensive than on the water in ponds located in the vicinity of a post-flotation waste heap. Monitoring of surface and underground waters, if limited only to the dissolved elements, can lead to faulty conclusions about environmental pollution. The bottom sediments mainly contain easily mobilised phases, and water-sediment equilibrium could be changed easily.  相似文献   
97.
The ribbon type Lake Durowskie (Western Poland) is currently undergoing a sustainable restoration process due to water quality deterioration, manifested in water blooms, low transparency, and oxygen deficits near the bottom sediments. Three restoration methods were applied: (i) hypolimnion aeration using two wind-driven pulverizing aerators installed at the deepest places, (ii) phosphorus inactivation using small doses of iron sulfate and magnesium chloride several times a year, and (iii) biomanipulation using pike fry stocking. Research on the exchange of phosphorus in the sediment-water interphase was conducted in the years 2009–2016 to determine the multiannual changes of internal phosphorus loading from bottom sediments during the restoration process. The sustainable approach resulted in a decrease of internal phosphorus loading and a gradual increase in the sorption capacity of bottom sediments, particularly noticeable in the last 2 years. The content of phosphorus in the sediment and in the interstitial water fluctuated, showing an increase during the first years of restoration and then a gradual decrease. It was proved that the process of sustainable restoration is cheap and does not interfere strongly with the ecosystem, although it is long-lasting. It should be continued for many years, especially in the case of continuous external loading of the lake with nutrients from the catchment area, i.e., until the water quality in the main tributary improves and the lake ecosystem stabilizes.  相似文献   
98.
Bark beetles (Coleoptera: Curculionidae, Scolytinae) are commonly recognised as important agents of tree mortality in coniferous forests of the Western Carpathians. They, together with weevils, are consistently associated with ophiostomatoid fungi. Information regarding conifer beetle-associated fungi in the Western Carpathians remains incomplete and unreliable, particularly with respect to fir-infesting bark beetles. This study aims to clarify associations between fungi in the genera Graphilbum, Leptographium, Ophiostoma and Sporothrix (Ophiostomatales) and their beetle vectors in Norway spruce (Picea abies), European larch (Larix decidua) and silver fir (Abies alba). Samples associated with 20 bark beetle species and weevils were collected from nine stands in Poland and the Czech Republic. Fungi were isolated from adult beetles and galleries. Isolates were identified based on morphology, DNA sequence comparisons for four gene regions (ITS, LSU, ß-tubulin, TEF 1-α) and phylogenetic analyses. In total, 46 distinct taxa were identified, including 25 known and 21 currently unknown species. Several associations between fungi and subcortical insects were recorded for the first time. In addition, O. borealis and O. quercus were detected from A. alba for the first time. The composition of the fungal communities varied among the studied tree species and to a lesser degree among the beetle species. The spruce-infesting bark beetles were commonly associated with species of Leptographium s. l. and Ophiostoma s. str.; the larch-infesting bark beetles were often associated with Ophiostoma s. str. and Sporothrix, while the fir-infesting bark beetles were commonly associated with Ophiostoma s. str. and Graphilbum. The most commonly encountered fungal associates of the examined insects were (a) Grosmannia cucullata, G. piceiperda, Grosmannia sp. 1, Ophiostoma macroclavatum and O. piceae with the spruce-infesting bark beetles; (b) O. pseudocatenulatum and Sporothrix sp. 1 with the larch-infesting bark beetles; and (c) O. piceae, Ophiostoma sp. 2 and Graphilbum sp. 2 with the fir-infesting bark beetles. The differences in fungal associates among the bark beetle species occurring on P. abies, L. decidua and A. alba could be linked to the different habitats that these beetles occupy.  相似文献   
99.
Milt of the Leuciscus idus L. was collected from five experimental groups, and selected parameters of its quality were analysed for 36 h (group II), 60 h (group III), 84 h (group IV) and 108 h (group V), respectively, after hormonal stimulation with Ovopel (1 granule kg?1 of body weight). The control (group I) fish were not subjected to hormonal stimulation. The highest milt volume was obtained from the fish in group IV (0.70 ± 0.55 mL), where the largest volume of milt expressed per kilogram was also obtained (3.03 ± 1.94 mL kg?1). Significant differences were also found in milt volumes obtained between group I and groups III (P<0.01) and IV (P<0.05). The highest percentage of motile spermatozoa was found in the milt of group IV (59%); significant differences were found between group I and groups II (P<0.01) and III (P<0.001). The value of osmotic pressure of seminal plasma was the highest in group IV (203.19 ± 37.63 mOsm kg?1), and the lowest in group I (118.31 ± 41.13 mOsm kg?1). Parameters determining milt quality and quantity indicate that the period of 60–84 h after hormonal stimulation with Ovopel is optimal for obtaining milt from ide.  相似文献   
100.
Purpose

The aims: (1) to investigate the role of the in situ weathering of bedrock in providing substrate for soil formation; (2) to evaluate the aeolian contribution to the mountainous soils in the vicinity of thick loess cover; and (3) to determine the influence of aeolian silt on further soil development.

Materials and methods

The sampled sites were arranged along the slope toposequence, where an aeolian/silt admixture possibly occurred. Each soil catena started at the top of a hill and ended at its foot. Such an arrangement of the soil profiles ensured the tracking of loess thickness variations and detection of the depth of the residuum-derived materials. One reference soil profile, consisting of aeolian silt deposits, was made. The following soil properties were determined: pH, organic carbon content, soil texture, exchangeable acidity, exchangeable ions and geochemistry. In addition, thin sections were prepared from rock samples to confirm the type of bedrock present.

Results and discussion

The soils in the studied area were classified as Cambisols, Luvisols and Stagnosols, characterised by silt loam texture and a high content of elements indicating an aeolian silt contribution—Hf (7.4 to 14.8 ppm) and Zr (274.4 to 549.0 ppm). These values differ strongly from the residues typical of weathered quartzite, greywacke or catalasite substrates, which generally have low concentrations of Hf and Zr (0.7 to 7.0 ppm and 26.0 to 263 ppm, respectively). Based on the morphological, textural and geochemical data of the studied soils, three layers were distinguished, which show different inputs of aeolian silt: (1) an aeolian silt mantle; (2) a mixed zone in which loess was incorporated into the local material; and (3) a basal zone, free of the influence of aeolian silt. Based on the obtained results, a hypothetical pathway for soil formation in mountainous areas, influenced by aeolian silt admixing, was proposed.

Conclusions

Our study demonstrates that the soils developed in the Opawskie Mountains are characterised by an aeolian silt influence. This differentiates them from weakly developed soils, which comprise materials formed during in situ weathering only. Materials originating from bedrock weathering did not play an independent role as the parent material for the studied pedons. Aeolian silt was admixed with already existing autochthonous substrates, or completely replaced them. This influence on the soil formation resulted in the occurrence of Luvisols, Stagnosols and Cambisols. Such soils cannot be formed from the weathering of quartzites and greywackes, which contribute to a less structure-forming medium.

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