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41.
This study was conducted to assess the stress response of Southern chamois (Rupicapra pyrenaica) to capture and physical restraint and the effects of acepromazine (a short-acting neuroleptic) on this response. Forty free-ranging Southern chamois were captured, injected intramuscularly with acepromazine (19 animals, randomly selected) or saline (the other 21 animals), and physically restrained for 3 h. Heart rate and body temperature were monitored with telemetric devices, and blood samples were obtained at capture and every hour thereafter to determine hematologic and serum biochemical parameters. The lower heart-rate variability, temperature, erythrocyte count, hemoglobin concentration, packed cell volume (PCV), and serum creatine kinase activity in the animals treated with acepromazine indicated that this agent reduced the adverse effects of stress. According to the differences in heart rate, erythrocyte count, hemoglobin concentration, PCV, lymphocyte count, and serum concentrations of glucose, creatinine, chloride, and potassium, alpha-adrenergic stimulation by catecholamines seemed to be stronger in females, whereas the adrenal-cortex reaction seemed to be stronger in males. The differences in erythrocyte parameters, temperature, serum creatine kinase activity, and serum concentrations of potassium and chloride indicated that acepromazine's beneficial effects were greater in females.  相似文献   
42.
Journal of Plant Diseases and Protection - Pepino mosaic virus (PepMV) disease causes important losses in tomato (Solanum lycopersicum) yield around the world. In order to find new sources of...  相似文献   
43.
OBJECTIVE: To compare cross-sectional anatomic specimens with images obtained via magnetic resonance imaging (MRI) of the coelomic structures of loggerhead sea turtles (Caretta caretta). ANIMALS: 5 clinically normal live turtles and 5 dead turtles. PROCEDURES: MRI was used to produce T1- and T2- weighted images of the turtles, which were compared with gross anatomic sections of 3 of the 5 dead turtles. The other 2 dead turtles received injection with latex and were dissected to provide additional cardiovascular anatomic data. RESULTS: The general view on the 3 oriented planes provided good understanding of cross-sectional anatomic features. Likewise, major anatomic structures such as the esophagus, stomach, lungs, intestine (duodenum and colon), liver, gallbladder, spleen, kidneys, urinary bladder, heart, bronchi, and vessels could be clearly imaged. It was not possible to recognize the ureters or reproductive tract. CONCLUSIONS AND CLINICAL RELEVANCE: By providing reference information for clinical use, MRI may be valuable for detailed assessment of the internal anatomic structures of loggerhead sea turtles. Drawbacks exist in association with anesthesia and the cost and availability of MRI, but the technique does provide excellent images of most internal organs. Information concerning structures such as the pancreas, ureters, intestinal segments (jejunum and ileum), and the reproductive tract is limited because of inconsistent visualization.  相似文献   
44.
During the process of breeding programmes, several resistance genes have been introgressed into tomato (Solanum lycopersicum) cultivars from different wild tomato relatives. A number of these resistance genes have been mapped to chromosome 6. Among them, Ty-1 and Mi, which confer resistance to Tomato yellow leaf curl disease and to Meloidogyne spp., respectively, are in most cases incorporated in commercial hybrids. Several molecular markers tightly linked to Mi have been identified. This study was conducted in order to find an informative molecular marker linked to Ty-1. Six markers mapped in the same region as Ty-1 were analysed in plant material carrying different combinations of Ty-1 and Mi alleles. Three of the six markers revealed polymorphism among the assayed accessions. One allele of JB-1 marker showed association with Ty-1. Furthermore, the presence of Mi did not interfere with the results. The analysis of several accessions of wild tomato relatives with the three polymorphic markers allowed the establishment of the origin of the alleles found in cultivated plant material, showing that introgressions from S. lycopersicum, S. pimpinellifolium and S. habrochaites will not interfere with the results of this marker which tags Ty-1. Furthermore this analysis enabled the location of CT21, the RFLP marker from which JB-1 was designed.  相似文献   
45.
Narrow intraspecific variation for sugar content in pepino (Solanum muricatum Aiton) hinders the development of new pepino cultivars with improved fruit quality. However, some wild related species have high soluble solids concentration (SSC) and titratable acidity (TA). Generation means analysis was used to estimate genetic parameters for SSC, TA and ascorbic acid concentration (AAC) in two families of interspecific crosses between a S. muricatum parent (Sm-32) and one accession of each of the wild species Solanum caripense (Sc-4) and Solanum tabanoense (St-1). In both families, the additive effect [d] was the only significant parameter for SSC, the alleles of wild species contributing positively to increasing SSC values. For TA, genetic effects associated with additivity [d] and dominance [h] were detected in both families. Additionally, in Sm-32 × Sc-4 nonallelic interactions associated with dominance ([j] and [l]) were significant. For this trait, alleles from the wild species contribute additively to a high value of the character, but are recessive to those of the cultivated S. muricatum. No genetic variation was found for AAC. Broad-sense heritabilities for SSC and TA were intermediate (0.40 to 0.50). Positive significant genetic correlations (around 0.68 in both families) were found between SSC and TA. The results obtained in backcrosses of interspecific hybrids to S. muricatum, together with the estimates of genetic advance after selection, indicate that recovery of individuals with higher SSC and TA and adequate SSC/TA ratio can be achieved in a few backcrosses. In conclusion, this work indicates that wild species S. caripense and S. tabanoense are worthy sources of variation for improving pepino fruit quality. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
46.
Summary The maize populations BS13 (S2) C4 and Lancaster are compared with respect to their potential as forage maize. In light of the preliminary results, the Lancaster population was chosen for a more thorough study.The determination of NDF gave a sufficiently precise estimate of the stover digestibility within our experimental conditions. The heritability of stover and grain production was 0.59 and 0.30, respectively, whilst that of the stover NDF was 0.32.The additive genetic correlation between NDF and stover production, possibly attributable to the architecture of the plant, favours the selection of genotypes that produce more and better forage.  相似文献   
47.
Cucurbita pepo is a worldwide cultivated vegetable of American origin. Most of the widely grown commercial types are known as summer squashes and belong to the elongated forms of C. pepo ssp. pepo (Cocozelle, Vegetable marrow and Zucchini groups). These forms were developed in Europe after the arrival of the first American landraces through a process of selection and fixation that led to a loss of genetic diversity. Part of the genetic variability of the first American cultigens remains intact in diverse landraces that are still cultivated for self-consumption and sale in local markets. Using the first collection of genomic and EST-derived microsatellites that has just become available for the species, we compared the natural variation present in a collection of Spanish landraces with that of a set of commercial varieties and hybrids, representing current summer squash market offerings. A total of 194 alleles allowed us to distinguish all the genotypes, even those that were closely related. In general, Cocozelle and Vegetable marrow, groups with considerably long histories, were more variable than the Zucchini group, of more recent origin. We found significant genetic diversity among landraces. The variation present among landraces belonging to the Zucchini group was larger than that of the commercial cultivars. Cluster, principal coordinate and population structure results suggested that the variation of the Spanish landraces has not been extensively used in breeding. Commercial summer squashes can therefore benefit from this underexploited variability, especially from certain landraces that already display favourable commercial traits.  相似文献   
48.
In 2001 and 2002, an outbreak of a previously unreported disease, associated with a border disease virus (BDV), caused high mortality in the Southern chamois (Rupicapra pyrenaica) population in the Alt Pallars-Aran National Hunting Reserve in the Catalan Pyrenees (NE Spain). Between 2002 and 2006, sera and/or tissue samples taken from 116 healthy chamois shot during the hunting season, plus 42 from chamois affected by different diseases, were studied. A blocking enzyme-immunosorbent assay (ELISA) was used to study pestivirus seroprevalence in 114 healthy hunted and 31 diseased chamois, yielding positive results in 73.7 and 22.6% of the chamois, respectively. Comparative virus neutralization tests (VNT) performed on 42 seropositive samples with 6 pestivirus strains yielded statistically higher titres to BDV Spain 97, followed by BDV chamois, BDV 137/4, BDV Moredun, Bovine Diarrhoea virus-1 (BVDV-1) NADL and BVDV-2 atypical. Virological investigations for pestivirus detection were performed using an antigen ELISA test in 82 healthy and 18 diseased chamois, RT-PCR in 16 healthy and in all diseased chamois, and virus isolation in 14 diseased chamois. No viral antigen was detected in any of the healthy animals. A pestivirus, characterized as BDV by monoclonal antibodies, was detected in the 10 chamois showing clinical signs consistent with BDV infection. Sequence analysis in the 5' untranslated region (5'-UTR) revealed that they were grouped into the BDV-4 genotype. In the remaining chamois, infectious keratoconjunctivitis, pneumonia, trauma and contagious ecthyma were diagnosed. The cause of death was unknown in five chamois. The results suggest that the infection has become endemic in the population and that it could have a significant impact on chamois population dynamics.  相似文献   
49.
The purpose of this study was to evaluate the effect of two dry extruded diets on growth and nutritional composition of digestive gland (DG) and muscle of Octopus vulgaris. Both artificial diets (FMK and 3FMK) were composed of gelatin, maltodextrin, yolk, fish and krill meal. The 3FMK diet contained more fishmeal (3×) than the FMK diet. These diets were compared with a control frozen diet consisting of golden grey mullet (Liza aurata) and crab (Liocarcinus depurator). The 3FMK diet promoted higher intakes and feed efficiency than FMK diet, resulting in larger growths (296 respect to 158 g in 42 days; 0.81% vs. 0.78% body weight/day). There was significantly lower moisture, protein and ash content in digestive glands of animals fed pellets (P < 0.05). No significant differences were observed on nutritional composition of muscle among the three groups. Even though the results were still below those of the control group (increase of 1258 g), the good performance in terms of acceptance and growth showed that this extruded diet can be the starting point to develop a commercial feed for this species.  相似文献   
50.
The present work studies the growth and body composition of 18 Octopus vulgaris (6 per treatment) fed two extruded diets, namely FMS and 3FMS, based on different fish and squid meal ratios (1:1, and 3:1 respectively). The diets are compared with a control diet based on crab (Carcinus mediterraneus) and bogue (Boops boops). The growing tests were conducted on animals placed in individual 300 L rectangular fibreglass tanks in an open seawater system, containing PVC tubes as shelters, resulting in 100% survival rate. The control group exhibited the highest specific growth rates (SGR = 2.14%BW day?1), while values of around 0.69%BW day?1 were achieved by octopuses fed the extruded diets. Even though the three groups of animals showed similar digestive gland indexes, the two extruded diets promoted significant differences in the muscle composition and fatness of the digestive gland. Digestibility of dry matter was not affected by the type of extruded diet, obtaining ADC values of around 88%. The results suggest that squid and fish meal can be both used in dry pelleted extruded diets, with moderate acceptance by the octopus, even though the formulation must be optimized with the aim of improving acceptability and achieve growths in the range of natural diets.  相似文献   
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