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Of 17 foals born on a Thoroughbred breeding farm between March and April 1995, infection with equine herpesvirus type 1 (EHV-1) was associated with neonatal morbidity in 5 foals, 3 of which died or were euthanized. Morbidity and mortality were associated with pulmonary inflammation, and EHV-1 was identified in the lungs of the 3 foals that died. All neonatal EHV-1 infections occurred in foals of mares housed in the same pasture and barn. No other clinical manifestations of EHV-1 infection (eg, abortion, neurologic disease, or respiratory disease) occurred during this outbreak. Three foals were treated with acyclovir (1 died, 2 survived), which may have influenced the clinical outcome in the surviving foals.  相似文献   
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A. Spada    R. Mantegazza    M. Biloni    E. Caporali  F. Sala 《Plant Breeding》2004,123(2):105-111
Two molecular marker approaches [amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR)] were employed to study genomic relationship among 96 rice cultivars. These included most of the best reputed Italian accessions. AFLP produced 461 fragments, 248 (53%) of which were polymorphic, SSR produced four to 11 alleles in the 12 genomic loci investigated. Genomic similarity was estimated independently for the two molecular marker techniques. Both AFLP and SSR dendrograms agree in splitting the cultivars into two main clusters: a small one, comprising four exotic accessions, and a larger one which could be split into four subgroups. These were also analysed on the basis of historical and pedigree information. This is the first report on the application of DNA polymorphism analysis to reveal genomic relationship among cultivated Italian rice germplasm. Results will be useful for breeding programmes.  相似文献   
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The classical recessive mouse mutant, Purkinje cell degeneration (pcd), exhibits adult-onset degeneration of cerebellar Purkinje neurons, retinal photoreceptors, olfactory bulb mitral neurons, and selected thalamic neurons, and has defective spermatogenesis. Here we identify Nna1 as the gene mutated in the original pcd and two additional pcd alleles (pcd2J and pcd3J). Nna1 encodes a putative nuclear protein containing a zinc carboxypeptidase domain initially identified by its induction in spinal motor neurons during axonal regeneration. The present study suggests an unexpected molecular link between neuronal degeneration and regeneration, and its results have potential implications for neurodegenerative diseases and male infertility.  相似文献   
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Eleven gastrointestinal neoplasms from 10 aged horses and 1 pony were examined grossly, his tologically, immunohistochemically, and (in two cases) ultrastructurally. Clinical signs were associated with two neoplasms, and the other nine tumors were incidental findings at laparotomy or necropsy. The neoplasms were solitary (9/11) or multifocal (2/11), well demarcated, serosal or mural masses of stomach (1), jejunum (1), ileum (3), cecum (5), and/or colon (2). Microscopic examination revealed discrete spindle cells arranged in compact patterns with fascicles and whorls or cribriform pattern with fascicles and rare palisades, often with a myxoid interstitial matrix. Three tumors infiltrated between the muscularis interna and the muscularis externa at the myenteric plexi. All neoplasms were vimentin positive, 3/11 were S-100 positive, 2/11 were muscle actin positive, and no neoplasm was positive for glial fibrillary acid protein, desmin, factor VIII, chromogranin, or neuron-specific enolase. Of the two tumors studied ultrastructurally, one contained an admixture of smooth muscle cells and cells resembling Schwann cells, and the second was populated by homogeneous fusiform mesenchymal cells separated by homogeneous matrix. Gastrointestinal stromal tumors (GIST) have been recognized in humans, more recently in dogs and nonhuman primates, and now in equids. Most of these tumors are comprised of a loosely arranged network of spindled cells separated by myxoid matrix. GIST may be composed of myogenic, neurogenic, combined myogenic and neurogenic, and undifferentiated mesenchymal cells.  相似文献   
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The effect of some 1,3,5-triazine herbicides, on the rate of oxidative decarboxylation of tryptophan by peroxidase from corn seedlings, varied with the concentration. Atrazine was stimulatory in vivo at 10-6M but not at 108 M or lower, whereas terbutryne was inhibitory at 10-6M but not at 10-8M or below. Prometryne inhibited enzyme activity at 10-6M and stimulated it at 10-10M and at 1012M, while simazine caused stimulation at 10-6M and inhibition at 10?10M and 10?12M. Atraton reduced enzyme activity at 10?6M and 10?8M but had no effect at 10?10M and 10?12M. When peroxidase activity was assayed in acetone-dried powders from seeds, harvested from fields that had received typical atrazine applications, the quantities of tryptophan consumed were significantly less than the quantity determined in the control powder. From the results obtained, by incorporating dealkylated and 2-hydroxy metabolites of atrazine at 10?6M into the culture solutions, it seems possible that the inhibition observed may have been due to the presence of 4-amino-6-ethylamino-1, 3, 5-triazin-2-ol and/or 4, 6-diamino-1, 3, 5-triazin-2-ol residues in seeds from treated plots, even if, in previously reported experiments, analyses had not detected their presence.  相似文献   
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Objective-To determine glycohistochemical characteristics of enzootic nasal tumors (ENTs) of sheep, compare results for ENT with those of histologically normal nasal mucosa of sheep, and identify the histologic origin of ENT. Sample-ENT and nasal mucosa samples obtained from cadavers of 5 adult Lacaune sheep with ENT and 5 Lacaune sheep unaffected by ENT, respectively. Procedures-Samples of ENT and nasal mucosa were collected from cadavers of sheep and sectioned. Conventional and lectin histochemical analyses were used to identify glycoconjugates in tissue sections on the basis of their principal chemical groups and principal terminal or internal oligosaccharidic glucidic residues, respectively. Results-ENTs had papillary and tubular portions. Cells in the papillary portion of ENTs had secretion and surface glycoconjugates, which included sulfated glycosaminoglycans and neutral and sialilated glycoproteins. Cells in the tubular portion of ENTs had surface glycoconjugates, which included neutral and sialilated glycoproteins. Both portions of ENTs had C(4)-acetylated sialoderivatives that were not detected in sections of histologically normal nasal mucosa. Conclusions and Clinical Relevance-The papillary portion of ENTs in sheep may originate from respiratory glands and goblet cells. The tubular portion of ENTs in sheep may originate from olfactory glands. Presence of C(4)-acetylated sialoderivatives in cells of ENTs could confer resistance against pathogens to those cells.  相似文献   
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This study provides an updated picture of mammal invasions in Europe, based on detailed analysis of information on introductions occurring from the Neolithic to recent times. The assessment considered all information on species introductions, known extinctions and successful eradication campaigns, to reconstruct a trend of alien mammals' establishment in the region. Through a comparative analysis of the data on introduction, with the information on the impact of alien mammals on native and threatened species of Europe, the present study also provides an objective assessment of the overall impact of mammal introductions on European biodiversity, including information on impact mechanisms. The results of this assessment confirm the constant increase of mammal invasions in Europe, with no indication of a reduction of the rate of introduction. The study also confirms the severe impact of alien mammals, which directly threaten a significant number of native species, including many highly threatened species. The results could help to prioritize species for response, as required by international conventions and obligations.  相似文献   
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