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71.
The results of most studies show the beneficial effect of milking automation on production parameters of dairy cows, but its effect on fertility traits is debatable. Therefore, a study was undertaken to predict cow fertility – services per conception (SC) and calving interval (CI) – based on automatic milking system (AMS) data collected in the periparturient period subdivided into the second and first week before calving, 1–4, 5–7, 8–14, 15–21 and 22–28 days of lactation. SC and CI were predicted using daily indicators such as concentrate intake, number of milkings, cow box time, milking time, milking speed, colostrum and milk yield, composition, temperature and electrical conductivity. The study material was derived from the AMS management system and from the SYMLEK milk recording system. The analysis covered data for 16,329 milkings of 398 Polish Holstein-Friesian (PHF) cows, which were used in three AMS herds. The collected numerical data were statistically analysed by correlation analysis in parallel with decision tree technique (SAS statistical package). The present study showed that due to the low, mostly non-significant coefficients of correlation between AMS data collected between 2 weeks before and 4 weeks after calving, it is not possible to predict cow fertility based on single traits. It has been established that the decision tree method may help breeders, already during the postcalving period, to choose the level of factors associated with AMS milking, which will ensure good fertility of cows in a herd. The most favourable number of services per conception is to be expected from cows that were milked <1.6 times per day from 1 to 4 days of lactation and electrical conductivity of their colostrum did not exceed 69 mS during that time. In turn, shortest CI (366 days) will be characteristic of the cows whose average daily colostrum yield did not exceed 20.2 kg and their daily concentrate intake from 8 to 14 days of lactation was at least 5.0 kg.  相似文献   
72.
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   
73.
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   
74.
DNA polymorphisms among 6 cultivars of Fragaria × ananassa (Duch.) and 13salinity tolerant clones were evaluated using simplified – PstI based Amplified Fragment Length Polymorphism procedure(PstIAFLP). Out of 129 amplification products obtained with 10 selective primers, 116 markers were polymorphic and could be used to distinguish all analyzed materials. Coordinate and cluster analyses revealed 2 main groups of clones and divided strawberry cultivars (CUL) and tested F1 hybrids of ‘Sweet Heart’(HYB). Mean genetic similarities in groups of cultivars and selected breeding lines (SEL) were significantly higher (0.722 and0.706, respectively, p < 0.05) than in group of SH hybrids (0.485). Results suggest that PstIAFLP method is sufficient for effective identification and useful for assessing the level of genetic diversity in strawberry cultivars and breeding lines. The presented method can bean alternative multilocus marker system to widespread RAPD method. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
75.
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   
76.
Atopic dermatitis is a common allergic skin disease in dogs. The aim of this study was to examine the possibility of a correlation between biophysical skin variables: skin hydration (SH), skin pH, and erythema intensity measured in 10 different body regions and both total Canine Atopic Dermatitis Extent and Severity Index (CADESI-03) and CADESI measured in a given region (CADESI L). The study was conducted using 33 dogs with atopic dermatitis. The assessment of the biophysical variables was done in 10 body regions: the lumbar region, right axillary fossa, right inguinal region, ventral abdominal region, right lateral thorax region, internal surface of the auricle, interdigital region of right forelimb, cheek, bridge of nose, and lateral site of antebrachum. Positive correlations were found between SH and CADESI L for the following regions: the inguinal region (r = 0.73) and the interdigital region (r = 0.82), as well as between total CADESI and SH on digital region (r = 0.52). Also, positive correlations were reported for skin pH and CADESI L in the lumbar region (r = 0.57), the right lateral thorax region (r = 0.40), and the lateral antebrachum (r = 0.35). Positive correlations were found in the interdigital region between erythema intensity and the total CADESI-03 (r = 0.60) as well as the CADESI L (r = 0.7). The results obtained suggest that it may be possible to use skin hydration, pH, and erythema intensity to assess the severity of skin lesion but positive correlation was only found in < 13.3% of possible correlations and usage of these measures in dogs is limited.  相似文献   
77.
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   
78.
79.
Bark weevils are consistently associated with various fungi. They act as effective vectors for root-rot fungi, the rust pathogen and the ophiostomatoid fungi. In comparison with bark beetles, the interaction between ophiostomatoid fungi and bark weevils has been poorly studied in Europe. This study aims to clarify the ties among ophiostomatoid fungi and their weevil vectors in Pinus sylvestris. Samples associated with three bark weevils, including Pissodes castaneus, P. piniphilus and P. pini were collected from seven pine stands in Poland. Fungi were isolated from laboratory-reared and field-collected beetles, larvae and galleries of weevils. Isolates were identified based on morphology, DNA sequence comparison for two gene regions (ITS, ß-tubulin) and phylogenetic analyses. Fourteen morphological and phylogenetic ophiostomatoid species were identified among the 1,219 isolates. These 14 species included 11 novel associations between fungi and bark weevils. The most commonly encountered fungal associates of bark Pissodes species were Leptographium procerum, Ophiostoma quercus and O. minus. The spectrum of fungal associates was similar in three bark weevil species, despite some differences between species. Except for P. castaneus, all species of bark weevil were frequently associated with ophiostomatoid fungi. Pissodes castaneus does appear to be a consistent vector of L. procerum and Sporothrix inflata while O. minus, O. quercus and O. cf. rectangulosporium were often found in association with P. piniphilus and P. pini.  相似文献   
80.
Understanding individual movements in heterogeneous environments is central to predicting how landscape changes affect animal populations. An important but poorly understood phenomenon is behavioural response to habitat boundaries and the way animals cross inhospitable matrix surrounding habitat patches. Here, we analyze movement decisions, flight behaviour, and activity of the endangered scarce large blue Phengaris (Maculinea) teleius, focusing on the differences among the patterns observed in patch interior, at patch boundaries and within matrix. The probability of crossing an external patch boundary, regardless of the land use in the adjacent area, was considerably lower than crossing a ‘control line’ within patch interior. Movement distances, flight durations and net squared displacement were largest in matrix, while similarly smaller at patch boundaries and in patch interior. The distribution of angles between successive movements was clearly clustered around 0° (indicating flight in a straight line) in matrix and at patch boundaries, but not in patch interior. There were no differences in time spent on foraging, resting and ovipositing between patch interior and boundaries, but the first two activities rarely, and oviposition never, happened in matrix. Our results suggest that although P. teleius adults do not avoid using the resources located in the boundaries of habitat patches, they often return to the interior of the patches when crossing their boundaries. However, having entered the matrix the butterflies perform relatively long and straight flights. The estimated probability of emigration and net squared distance implies that the dispersal between local populations is common in this species in the studied area.  相似文献   
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