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71.
A series of derivatives of 9-aminofluoren-9-ylphosphonic acid (phosphonic analogues of morphactins) were synthesized and screened for herbicidal activity against Lepidium sativum, Cucumis sativus and Lycopersicon esculentum. Ethyl 9-(N-alkylamino)fluoren-9-yl(phenyl)phosphinates appeared to be equipotent with glyphosate and thus may be recognized as new lead compounds for further structural modifications.  相似文献   
72.
Biological activity tests were performed on alpha-galactoside preparations obtained from Lupinus angustifolius L. cv. Mirela (alkaloid-rich) and Pisum sativum L. cv. Opal seeds. The studies included the following tests: acute toxicity, cytotoxic test, delayed type hypersensitivity (DTH), plaque-forming cell number (IgM-PFC), and influence on the growth of bifidobacteria and coliform presence in rat colon. Results of these studies showed that alpha-galactosides from lupin and pea seeds were essentially nontoxic. Their acute toxicity (LD(50)) in mice was >4000 mg kg(-1) of body weight. alpha-galactoside preparations were not cytotoxic for mouse thymocytes in vitro. The in vitro test shows that oligosaccharides from lupin and pea are utilized by selected beneficial colon bacterium strains. The in vivo experiment demonstrated that alpha-galactosides from legume significantly influenced the growth of bifidobacteria in rats colon. Simultaneously, the decrease of the coliform presence was observed. The chemical composition of the tested preparations had no significant effect on their biological activity.  相似文献   
73.
The effect of eleven metal ions: Co(II), Cr(VI), Mg, Mn(II), Mo(VI), Ni(II), Pb(II), Se(IV), Ti(III), V(IV) and Zn and several combinations of them were tested for their effect on the growth of Saccharomyces cerevisiae (Mautner). The effects depended on the metal and its concentration as well as in some cases on the duration of the experiment.  相似文献   
74.
Invasive alien plants constitute a major threat to local biodiversity. Moreover, their appearance often coincides with land use change. Many endangered groups of organisms suffer from habitat loss, which is often a consequence of the invasion of alien plants. This paper examines how invasive alien goldenrods Solidago spp. affect the richness of endangered grassland bird species and numbers of breeding pairs in abandoned meadows in southern Poland. Meadows invaded by goldenrods (n = 15) had lower bird species richness and a lower number of breeding pairs than meadows in which goldenrods were absent (n = 15). Two important factors positively influencing bird species richness were meadow area and shrub density (the latter only in meadows without goldenrods). Moreover, both the index of potential food density (number of butterflies) and plant species richness were much lower in meadows invaded by goldenrods than in meadows without these plants. Urgent action aimed at preventing the invasion of alien goldenrods in abandoned meadows is needed and such measures should involve regular mowing. Our results also highlight the fact that land abandonment in Central and Eastern Europe is not necessarily as beneficial for biodiversity as it is commonly believed and it may even lead to a decrease in the populations of several bird species in the agricultural landscape.  相似文献   
75.
The effect of sixteen metal ions: Al, Cd, Co(II), Cr(III), Cr(VI), Cu(II), Fe(III), Li, Mg, Mn(II), Mo(VI), Ni(II), Pb(II), Se(IV), V(V), and Zn on the mortality and infectivity ofHeterorhabditis bacteriophora were observed over a 96 hr period. All ions except Pb(II) even at naturally unrealistic concentrations did not cause the mortality of the nematodes. A weak vitalizing effect could eventually be observed with Mn(II), Mg, Fe(III) and Ni(II) (Table 1). However, such treatment generally lowered infectivity of the nematodes with respect to wax moth caterpillars.Galleria mellonella. This effect was particularly significant with Ni(II) and Pb(II).  相似文献   
76.
In this study, different Polish cultivars of blue-berried honeysuckles (Lonicera caerulea L.), wild and bog bilberry, were analyzed for bioactive compounds. The chemical properties verified included composition of anthocyanins and other polyphenols, antioxidant activity, and profiles of antioxidants by HPLC postcolumn derivatization or TLC. The antioxidant activities of different blue-berried honeysuckle cultivars were similar to that of wild-growing bilberries (ranging from 170 to 417 μmol TE/g dm in ABTS and from 93 to 166 μmol TE/g dm in DPPH and Folin-Ciocalteu tests). The major anthocyanin in the blue-berried honeysuckle was cyanidin-3-glucoside, which constituted 84-92% of the total anthocyanins. The TLC and HPLC postcolumn antioxidant profiles indicated that anthocyanins are the major antioxidants in all berries studied. Wild berries and the cultivars of the blue-berried honeysuckles are also a similar source of such minerals as K, Mg, and Ca.  相似文献   
77.
Background, aim, and scope  Ionic liquids (ILs) are a new class of alternative solvents that make ideal non-volatile media for a variety of industrial processes such as organic synthesis and biocatalysis, as alternative electrolytes, as phases and phase modifications in separation techniques, and as alternative lubricants. Once the large-scale implementation of ILs begins, the industrial application will follow. In view of their great stability, they could slip through classical treatment systems to become persistent components of the environment, where the long-term consequences of their presence are still unknown. Sorption on soils has a critical effect on the transport, reactivity, and bioavailability of organic compounds in the environment. So far, the IL sorption mechanism was investigated solely on the basis of batch experiments, which precluded any assessment of the dynamics of the process. An understanding of the mobility of ILs in soil columns is crucial for an accurate prediction of their fate in the soil. The aim of this study therefore was to investigate in detail the mobility of selected imidazolium ILs on three soil types. Moreover, it was decided to study these processes in soils from the coastal region (Gdańsk, Poland), which usually constitute a very important geochemical compartment, participating in the transport of contaminants on their way to the sea. Materials and methods  The mobility of alkylimidazolium ILs was investigated in columns containing soils from the coastal area. In addition, the sorption processes in all the soil systems studied were described isothermally and the equilibrium sorption coefficient was evaluated. The sorption capacities were determined according to OECD guidelines. Sorption dynamics was studied with use of polypropylene columns (diameter—10 mm, height—100 mm) packed with 10 g of soil. The ionic liquid solution was then injected into the soil column and left for 24 h to equilibrate. After this, a solution of 0.01 mM CaCl2 was pumped through the column at a rate of 0.3 ml min–1. Effluents were collected from the bottom of the column and analyzed by HPLC. Results  Sorption was strongest on the Miocene silt and the alluvial agricultural soil and weakest on the podsolic soil and Warthanian glacial till. The K d value of long-chain ILs was far higher than that of the short-chain ones. Among the substances tested, hydroxylated ILs were usually more weakly sorbed. Desorption of ILs is inversely correlated with sorption intensity. The experimental results of the column tests correlate well with those from batch experiments. In the cases of weakly binding soils, ILs were detected almost immediately in the eluent. The elution profiles of long-chain ILs indicate that these compounds are very strongly sorbed onto most soils, although certain amounts were transported through the soil. ILs exhibit a certain mobility in soils: in particular, salts with short and/or hydroxylated side chains are extremely mobile. Discussion  The results indicate a stronger binding of ILs in the first sorption layer; once the first layer is saturated, there are no more active sites on the soil surface (no free charged groups); hence, there are no more strong electrostatic binding sites, and dispersive interaction becomes the dominant interaction potential. The influence of the structure of the ILs, especially the side-chain length was also confirmed: The K d value of long-chain ILs was far higher than that of the short-chain ones. The long alkyl side chain facilitates dispersive interactions with soil organic matter and intermolecular binding, and the build-up of a second layer becomes possible. Among the substances tested, hydroxylated ILs were usually more weakly sorbed. The hydroxyl group in the side chain can alter the polarity of the compound so strongly that interaction with organic matter hardly occurs; these salts then remain in the aqueous phase. The experimental results from the column tests correlate well with those from batch tests. In the weakly binding soils (with low organic matter), the only binding to the soil surface must be via electrostatic interactions, although intermolecular van der Waals (ionic liquid–ionic liquid) interactions could also be taking place. The elution profile maxima for organic rich soils are far smaller than for the other soils. In the former, hydrogen bonding, dispersive and π…π interactions play a more important part than electrostatic interactions. The rapidly “disappearing” maxima of the elution peaks may indicate that, after elution of ILs from the second layer, it is difficult to extract further sorbed ILs. In the first layer, the ILs are bound by much stronger electrostatic interactions. To break these bonds, a greater energy is required than that sufficient to extract ILs from double sorption layers. Results indicate, moreover, that hydrophobic ILs will be sorbed in the first few centimeters of the soil; migration into the soil will therefore be almost negligible. Conclusions  Sorption of ILs was the strongest in soils with the highest cation exchange capacities and a high organic content. ILs were also more strongly bound to the first sorption layer. The sorption coefficients of long-chain ILs were far higher than those of short-chain ones; usually, hydroxylated derivatives were the least strongly sorbed. Results of soil column experiments to investigate the mobility of ILs in soils correlated well with those from batch tests, and the elution profiles were also well correlated with organic matter content. The observed rapidly disappearing elution peak maxima probably indicate that, after elution of the ILs from the second layer, it is difficult to extract further sorbed compounds. Recommendations and perspectives  Obtained results gave an interesting insight into mobility of ionic liquids in soil columns. However, several questions are now opened. It is therefore necessary to undertake further studies focused on total cycle of ionic liquids in the soil environment. This should include their evapotrasporation (lysimeter test), bioaccumulation by plants as well as degradation and transformation processes (chemical, biological, and physical) typically occurring in soils. Moreover, a further risk assessment of ILs is desirable since this study has indicated that these compounds, especially those with low lipophilicities, are generally mobile in the soil matrix. It is already known that short-chain ILs are characterized by low toxicities; should they enter the environment, they will probably migrate within the soil and pose a risk of contamination of surface and ground waters. This topic is relevant to the audience. Environmental threat of short-chain ionic liquids is currently unknown. From the predictive point of view, judging on known low acute toxic effects or high polarities of these compounds seems to be not enough to confirm their “environmental friendliness”. If we are to fully understand the potential environmental effects, one should also have an insight into long-term biological consequences of these ionic liquids, including chronic toxicity tests, bioaccumulation, and biotransformation rates as well as stability against natural elimination mechanisms.  相似文献   
78.
79.
Microbial population and bioactive amine profile and levels of two lupin species (Lupinus luteus L. cv. 4492 and Lupinus angustifolius L. var. zapaton) and fenugreek (Trigonella foenum-graecum L.) seeds as affected by germination were investigated. Microbial population increased considerably mainly in the first stage of germination (2 days), then small changes in bacterial numbers were observed up to 5 days to levels between 7.8 and 8.9 log colony-forming units/g. Microorganisms belonging to the Enterobacteriaceae family were dominant for the legumes tested. Ungerminated legume seeds contained putrescine, cadaverine, histamine, tyramine, spermidine, and spermine. Bioactive amine levels found in fenugreek seeds were between 3- and 4-fold higher than those found in lupin seeds. The highest total amine levels were found in fenugreek seeds [162 mg/kg of dry weight (dw)], followed by L. angustifolius var. zapaton seeds (84 mg/kg of dw) and, finally, L. luteus cv. 4492 (46 mg/kg of dw) seeds. The concentration of individual amines showed a gradual rising trend during the germination period in all tested sprouts, reaching levels >3 times higher than those found in ungerminated seeds. After 5 days of germination, the fenugreek sprouts contained the highest amount of total bioactive amines. Tyramine was the predominant amine in both lupin varieties, whereas cadaverine was the main bioactive amine detected in fenugreek. The results of this work thus indicated that microbial population and biogenic amine levels in the studied lupin and fenugreek sprouts are not a risk for healthy consumers or for individuals with restricted activity of detoxification enzymes.  相似文献   
80.
The effect of estradiol-17β (E(2)) on the number and distribution of neurons in the caudal mesenteric ganglion (CaMG) supplying the ovary of adult pigs was investigated. Also, the numbers of ovarian dopamine-β-hydroxylase (DβH-), neuropeptide Y (NPY-), somatostatin (SOM-), galanin (GAL-) and estrogen receptor (ER)-immunoreactive perikarya as well as the density of the intraganglionic nerve fibers containing DβH and/or NPY, SOM, GAL were determined. E(2) was administered i.m. from day 4 of the first studied estrous cycle to the expected day 20 of the second studied cycle. Injections of E(2) (1) increased the E(2) level in the peripheral blood approximately 4-5 fold, (2) decreased the number of small-sized Fast Blue-positive postganglionic neurons in the CaMG, (3) decreased the number of small perikarya in the ventral, dorsal and central regions of the CaMG, (4) decreased the number of large perikarya in the dorsal and central regions, (5) decreased the number of small and large perikarya in the CaMG that were DβH(+)/NPY(+), (6) decreased the number of small DβH(+) but NPY(-) perikarya, (7) decreased the number of small perikarya coded DβH(+)/SOM(+) and DβH(+)/SOM(-), (8) decreased the number of small DβH(+)/GAL(-) perikarya, (9) decreased the number of small and large perikarya expressing ER subtypes α and β and (10) decreased the total number of nerve fibers in the CaMG containing DβH and/or NPY and DβH and/or GAL. These results show that long-term E(2) treatment of adult gilts downregulates the populations of both noradrenergic and ERs expressing ovarian neurons in the CaMG. Our findings suggest also that elevated E(2) levels that occur during pathological states may regulate gonadal function(s) by affecting ovary supplying neurons.  相似文献   
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