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1.
OBJECTIVES: To evaluate the effects of radiation synovectomy (RSYN) with holmium-166 ferric hydroxide macroaggregate (Ho-166 FHMA) on synovium and synovial fluid in normal metacarpo- and metatarsophalangeal joints of horses and to determine intraarticular distribution of radioactivity after Ho-166 FHMA treatment. STUDY DESIGN: Either Ho-166 FHMA or nonradioactive Ho-165 FHMA was injected into metacarpo- or metatarsophalangeal joints. ANIMALS: Six adult mixed-breed horses without any clinical evidence of metacarpo- or metatarsophalangeal joint disease. METHODS: Joints were injected with a single high dose of Ho-166 FHMA (mean, 1,000 MBq/joint) or a nonradioactive Ho-165 FHMA preparation (controls). Clinical examination, arthroscopy, synovial fluid analyses, and histologic studies were performed to detect effects of RSYN. Scintigraphy was used to localize intraarticular distribution of Ho-166 FHMA. RESULTS: Ho-166 FHMA treatment induced joint inflammation leading to regional edema, effusion, and scar tissue formation. Scintigraphy revealed the highest intensity of radioactivity in the proximal plantar joint pouch, at which the Ho-166 FHMA treatment caused multifocal necrosis. In the dorsal joint pouch, however, arthroscopic study and histologic analysis showed very little effect of RSYN. There was no regeneration of synovium evident within 2 months. Synovial fluid protein concentration was significantly (P <.01) elevated, and some residual radioactivity remained for 5 days after Ho-166 FHMA injection. CONCLUSIONS: Injection of a single high dose of Ho-166 FHMA caused multifocal necrosis of synovium and deep, soft-tissue injury in equine fetlock joints. CLINICAL RELEVANCE: Inflamed equine joints with synovial lining hyperplasia could benefit from Ho-166 FHMA-induced radiation synovectomy if excessive scar tissue formation can be avoided.  相似文献   
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Natural fruiting and sporulation of cone rusts were investigated in cones of Picea spp. and leaves of Prunus spp. in a botanical garden in northern Finland in 2007–2012. Thekopsora areolata was the most frequent cone rust in Picea abies cones, where it colonizes the host tissues and hinders normal seed development. Aecia of T. areolata were also common in cones of Picea engelmannii and occasionally in cones of P. glauca. Aecia of T. areolata sporulated in cones that were at least one year old. Chrysomyxa pirolata, another pathogenic cone rust, fruited and sporulated annually but infrequently in current‐year cones of P. abies. The spruce needle rust, Chrysomyxa ledi, fruited and sporulated commonly in current‐year cone scales of P. abies, P. omorika and P. glauca, while P. rubens, P. mariana and P. pungens appeared to be resistant during the study period. Chrysomyxa ledi did not affect seed development in infected cones. Uredinia of T. areolata frequently occurred on leaves of 41 Finnish and Russian cultivars, varieties or subspecies of Prunus padus L. ssp. badus and ssp. borealis and Pr. virginiana both in the botanical garden and in the field, while 13 exotic Prunus spp. lacked rust fruitbodies. All the Pr. padus cultivars were highly susceptible to T. areolata, thus, spreading the rust efficiently to surroundings. This is the first report of aecia of T. areolata in cones of P. engelmannii and P. glauca, and those of C. ledi in cones of P. omorika and P. glauca. Molecular identification confirmed the presence of T. areolata and C. pirolata on all hosts, and all samples of C. ledi belonged to the C. ledi‐rhododendri complex.  相似文献   
4.
Potato virus Y (PVY) is a major pathogen of potato and transmitted non-persistently by aphids. Aphis fabae is the main vector of PVY in the High Grade Seed Potato Production Area (HG area) in Finland, where the number of aphids and infection pressure with PVY are rather low, but problems with PVY occur in PVY-susceptible cultivars. The aim of the study was to test straw mulch, mineral oil, birch extract, and insecticides for control of PVY in small-scale field experiments and, additionally, at farm level in growers’ fields in the HG area of Finland. The insecticide esfenvalerate reduced the incidence of PVY in the progeny tubers by 29% in one of the 3 years, whereas other chemical treatments or birch extract had no significant effect on PVY incidence. Spraying foliage with mineral oil (Sunoco 11 E/3) reduced the incidence of PVY in 2 years by 43 to 58%, respectively. Straw mulch spread to the field at the time of plant emergence reduced PVY incidence in all 3 years by 50–70%. At farm level, straw mulch reduced the incidence of PVY in the progeny tubers by 25–47%, respectively, in both years tested; however, combining application of straw mulch and mineral oil did not further reduce incidence of PVY. Successful control of PVY in the HG area of Finland using straw mulch may be explained by transmission of PVY early in the growing season at the time of plant emergence and the relatively low number of vector aphids.  相似文献   
5.
The effects of inoculum load and watering regime on the transmission of Xanthomonas campestris pv. campestris from seed to seedlings of cauliflower were investigated. Seed, inoculated with different concentrations of bacteria, was sown in commercial module trays and subjected to four different watering regimes: high frequency overhead spray, low frequency overhead spray, high frequency capillary and low frequency capillary. Visible symptoms were recorded and leaf washings were carried out to detect the pathogen on symptomless plants. The effects of treatments on symptoms and on the proportion of contaminated but symptomless plants was similar. Initially, they were influenced only by the dose of bacteria with little difference between the watering regimes, but later the proportion of plants with symptoms was greater for plants subjected to overhead watering, due to spread and secondary infection. Generalised linear models were fitted to the data relating the proportion of symptomless contaminated plants or the proportion of plants with symptoms, p, to the mean dose of bacteria per seed, d, and the number of overhead waterings, noh. The equations were: p=1–exp(–0.014·d 0.32·noh 0.045) for symptomless contaminated/infected plants and p=1–exp(–0.0056·d 0.44·noh 0.014) for plants with symptoms. These models indicated that the one-hit probability for transmission of the pathogen (i.e. with/without visible symptoms) was 0.014 and for infection (i.e. with visible symptoms) was 0.0056.  相似文献   
6.
Fusarium is one of the most destructive fungal genera whose members cause many diseases on plants, animals, and humans. Moreover, many Fusarium species secrete mycotoxins (e.g. trichothecenes and fumonisins) that are toxic to humans and animals. Fusarium isolates from date palm trees showing disease symptoms, e.g. chlorosis, necrosis and whitening, were collected from seven regions across Saudi Arabia. After single-sporing, the fungal strains were morphologically characterized. To confirm the identity of morphologically characterized Fusarium strains, three nuclear loci, two partial genes of translation elongation factor 1 α (tef1α) and β-tubulin (tub2), and the rDNA-ITS region, were amplified and sequenced. Of the 70 Fusarium strains, 70 % were identified as F. proliferatum that were recovered from six regions across Saudi Arabia. Fusarium solani (13 %), as well as one strain each of the following species: F. brachygibbosum, F. oxysporum, and F. verticillioides were also recovered. In addition, five Fusarium-like strains were recognized as Sarocladium kiliense by DNA-based data. The preliminary in vitro pathogenicity results showed that F. proliferatum had the highest colonization abilities on date palm leaflets, followed by F. solani. Although F. oxysporum f. sp. albedinis is the most serious date palm pathogen, F. proliferatum and F. solani are becoming serious pathogens and efforts should be made to restrict and control them. In addition, the potential toxin risks of strains belonging to F. proliferatum should be evaluated.  相似文献   
7.
Water-soluble extracts from the Mentha species M. aquatica L. and M. haplocalyx Briq., the hybrids M. x dalmatica L. and M. x verticillata L., the varieties M. arvensis var. japanensis [M. arvensis L. var. piperascens Holmes ex Christ] and M. spicata L. var. crispa Benth, and M. x piperita L. "Frantsila", M. "Morocco", and M. "Native Wilmet" cultivars were screened for potential antioxidative properties. These properties included iron(III) reduction, iron(II) chelation, 1,1-diphenyl-2-picrylhydrazyl radical scavenging, and the ability to inhibit iron(III)-ascorbate-catalyzed hydroxyl radical-mediated brain phospholipid peroxidation. Total phenol content and qualitative and quantitative compositional analyses of each extract were also made. The extracts demonstrated varying degrees of efficacy in each assay, with the M. x piperita "Frantsila" extract being better than the other extracts, except for ferrous iron chelation. With the exception of iron chelation, it appeared that the level of activity identified was strongly associated with the phenolic content.  相似文献   
8.
Brauns’ lignins present in the methanol extracts of fresh birch (Betula pendula) xylem and of sawn birch board subjected to vacuum drying were characterized by 1H and 13C NMR spectroscopy (1D and 2D), IR spectroscopy, gel permeation chromatography (GPC) and colour measurements (CIELab) in order to find out whether Brauns’ lignin could contribute to the colour change of sawn timber that occurred during vacuum drying. The two Brauns’ lignin samples contained about equal amounts of syringylpropane and guaiacylpropane units linked with β-O-4 and β–β side-chain structures. Molecular weight of the Brauns’ lignin of vacuum-dried birch board (acetylated: 5,200 g mol−1) was higher than that of the Brauns’ lignin of fresh birch wood (acetylated: 4,400 g mol−1). The Brauns’ lignin of vacuum-dried wood was also clearly darker and more prominently yellow and red; between the Brauns’ lignin samples was 23.59. The differences in the molecular weights and colours suggest that the Brauns’ lignin underwent a chemical change during vacuum drying of the wood and that this change may have affected the colour of the wood.  相似文献   
9.
Susceptibility of potential alternate host plants to pine stem rusts belonging to Cronartium spp. was artificially tested in Finland during 2012–2013. Forty‐three species representing 11 plant families were inoculated in the laboratory; 34 species (11 families) were inoculated in the greenhouse with aeciospores of Cronartium flaccidum or Cribicola. Twenty‐one selected species (10 families) were also exposed to natural inoculum of C. flaccidum in the field in two severely affected Pinus sylvestris stands. After 5–8 weeks’ incubation, C. flaccidum sporulated on 17 species (nine families) in the laboratory, 17 species (eight families) in the greenhouse and seven species (five families) in the field. Cronartium ribicola sporulated on three species (three families) in the laboratory or greenhouse. All of the hemiparasitic plants that belong to Orobanchaceae were infected by C. flaccidum, and several species supported rust sporulation when exposed to natural inoculum. Susceptible species belonged to genera Veronica, Euphrasia, Castilleja, Pedicularis, Rhinanthus, Saxifraga, Loasa, Ribes, Tropaeolum, Swertia, Physalis, Nicotiana, Hyoscyamus, Paeonia, Apocynum, Impatiens, Vincetoxicum and Myrica.  相似文献   
10.
Despite the promising antioxidant action of Lamiaceae herbs in vitro, human studies on these potential sources of dietary antioxidants have remained scarce. In this work, the phenolic acids recovered in human urine after single ingestion of Origanum onites extract were analyzed. The excretion was increased 4- and 2-fold during 0-24 and 24-48 h of the follow-up, respectively. The mean increase in the excretion of phenolic compounds exceeded the ingested amount of identified phenolic acids. The result can be partly explained by rosmarinic acid, the main identified phenolic constituent in the extract, as well as flavonoids present in minor amounts, presumably being metabolized into a double amount of simple phenolic metabolites. Furthermore, unidentified phenolic constituents in the extract partly contribute to the excretory increase. The main metabolite, p-hydroxybenzoic acid, was excreted rapidly. The results show that constituents of oregano extract and, in particular, their metabolites may contribute to the dietary intake of phenolic antioxidants.  相似文献   
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